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Wang H, Wang K, Zheng Y, Deng Z, Yu Z, Zhan H, Zhao Y. Kinematic patterns in performing trunk flexion tasks influenced by various mechanical optimization targets: A simulation study. Clin Biomech (Bristol, Avon) 2024; 120:106344. [PMID: 39260048 DOI: 10.1016/j.clinbiomech.2024.106344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2024] [Revised: 09/05/2024] [Accepted: 09/08/2024] [Indexed: 09/13/2024]
Abstract
BACKGROUND Low back pain is the most prevalent and disabling condition worldwide, with a high recurrence rate in the general adult population. METHODS A set of open-sourced trunk musculoskeletal models was used to investigate trunk flexion kinematics under different motor control strategies, including minimizing shearing or compressive loads at the L4/L5 or L5/S1 level. FINDINGS A control strategy that minimizes the load on the lower lumbar intervertebral disc can result in two kinematic patterns-the "restricted lumbar spine" and the "overflexed lumbar spine"-in performing the trunk flexion task. The "restricted" pattern can reduce the overall load on the lower lumbar levels, whereas the "overflexed" pattern can reduce the shearing force only at the L4/L5 level and increase the compressive and shearing forces at the L5/S1 level and the compressive force at the L4/L5 level. INTERPRETATION This study investigated the relationships between specific trunk kinematics in patients with low back pain and lumbar intervertebral loading via musculoskeletal modelling and simulation. The results provide insight into individualized treatment for patients with low back pain.
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Affiliation(s)
- Huihao Wang
- Shi's Center of Orthopedics and Traumatology (Institute of Traumatology, Shuguang Hospital), Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China.
| | - Kuan Wang
- College of Rehabilitation Sciences, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China
| | - Yuxin Zheng
- Shi's Center of Orthopedics and Traumatology (Institute of Traumatology, Shuguang Hospital), Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Zhen Deng
- Shanghai Baoshan District Hosptial of Integrated Traditional Chinese and Western Medicine, Shanghai 201999, China
| | - Zhongxiang Yu
- Shi's Center of Orthopedics and Traumatology (Institute of Traumatology, Shuguang Hospital), Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Hongsheng Zhan
- Shi's Center of Orthopedics and Traumatology (Institute of Traumatology, Shuguang Hospital), Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Yongfang Zhao
- Shi's Center of Orthopedics and Traumatology (Institute of Traumatology, Shuguang Hospital), Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
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Xu F, Lin J, Jiang S, Sun Z, Zhou S, Li Z, Wang S, Li W. In vivo segmental vertebral kinematics in patients with degenerative lumbar scoliosis. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2024; 33:571-581. [PMID: 37831181 DOI: 10.1007/s00586-023-07974-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 09/17/2023] [Accepted: 09/25/2023] [Indexed: 10/14/2023]
Abstract
PURPOSE This study aimed to find a standard of the vertebra kinematics during functional weight-bearing activities in degenerative lumbar scoliosis (DLS) patients. METHODS Fifty-four patients were involved into this study with forty-two in DLS group and twelve in the control group. The three-dimensional (3D) vertebral models from L1 to S1 of each participant were reconstructed by computed tomography (CT). Dual-orthogonal fluoroscopic imaging, along with FluoMotion and Rhinoceros software, was used to record segmental vertebral kinematics during functional weight-bearing activities. The primary and coupled motions of each vertebra were analyzed in patients with DLS. RESULTS During flexion-extension of the trunk, anteroposterior (AP) translation and craniocaudal (CC) translation at L5-S1 were higher than those at L2-3 (9.3 ± 5.1 mm vs. 6.4 ± 3.5 mm; P < 0.05). The coupled mediolateral (ML) translation at L5-S1 in patients with DLS was approximately three times greater than that in the control group. During left-right bending of the trunk, the coupled ML rotation at L5-S1 was higher in patients with DLS than that in the control group (17.7 ± 10.3° vs. 8.4 ± 4.4°; P < 0.05). The AP and CC translations at L5-S1 were higher than those at L1-2, L2-3, and L3-4. During left-right torsion of the trunk, the AP translation at L5-S1 was higher as compared to other levels. CONCLUSIONS The greatest coupled translation was observed at L5-S1 in patients with DLS. Coupled AP and ML translations at L5-S1 were higher than those in healthy participants. These data improved the understanding of DLS motion characteristics.
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Affiliation(s)
- Fei Xu
- Department of Orthopaedics, Peking University Third Hospital, No. 49 North Garden Road, Haidian District, Beijing, 100191, China
- Peking University Health Science Center, No. 38 Xueyuan Road, Haidian District, Beijing, 100191, China
- Beijing Key Laboratory of Spinal Disease Research, Beijing, China
- Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Jialiang Lin
- Department of Orthopaedics, Peking University Third Hospital, No. 49 North Garden Road, Haidian District, Beijing, 100191, China
- Beijing Key Laboratory of Spinal Disease Research, Beijing, China
- Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Shuai Jiang
- Department of Orthopaedics, Peking University Third Hospital, No. 49 North Garden Road, Haidian District, Beijing, 100191, China
- Beijing Key Laboratory of Spinal Disease Research, Beijing, China
- Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Zhuoran Sun
- Department of Orthopaedics, Peking University Third Hospital, No. 49 North Garden Road, Haidian District, Beijing, 100191, China
- Beijing Key Laboratory of Spinal Disease Research, Beijing, China
- Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Siyu Zhou
- Department of Orthopaedics, Peking University Third Hospital, No. 49 North Garden Road, Haidian District, Beijing, 100191, China
- Beijing Key Laboratory of Spinal Disease Research, Beijing, China
- Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Zhuofu Li
- Department of Orthopaedics, Peking University Third Hospital, No. 49 North Garden Road, Haidian District, Beijing, 100191, China
- Peking University Health Science Center, No. 38 Xueyuan Road, Haidian District, Beijing, 100191, China
- Beijing Key Laboratory of Spinal Disease Research, Beijing, China
- Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Shaobai Wang
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, School of Kinesiology, Shanghai University of Sport, Shanghai, 20043, China.
| | - Weishi Li
- Department of Orthopaedics, Peking University Third Hospital, No. 49 North Garden Road, Haidian District, Beijing, 100191, China.
- Beijing Key Laboratory of Spinal Disease Research, Beijing, China.
- Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China.
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McMullin P, Emmett D, Gibbons A, Clingo K, Higbee P, Sykes A, Fullwood DT, Mitchell UH, Bowden AE. Dynamic segmental kinematics of the lumbar spine during diagnostic movements. Front Bioeng Biotechnol 2023; 11:1209472. [PMID: 37840657 PMCID: PMC10568473 DOI: 10.3389/fbioe.2023.1209472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 09/15/2023] [Indexed: 10/17/2023] Open
Abstract
Background: In vivo measurements of segmental-level kinematics are a promising avenue for better understanding the relationship between pain and its underlying, multi-factorial basis. To date, the bulk of the reported segmental-level motion has been restricted to single plane motions. Methods: The present work implemented a novel marker set used with an optical motion capture system to non-invasively measure dynamic, 3D in vivo segmental kinematics of the lower spine in a laboratory setting. Lumbar spinal kinematics were measured for 28 subjects during 17 diagnostic movements. Results: Overall regional range of motion data and lumbar angular velocity measurement were consistent with previously published studies. Key findings from the work included measurement of differences in ascending versus descending segmental velocities during functional movements and observations of motion coupling paradigms in the lumbar spinal segments. Conclusion: The work contributes to the task of establishing a baseline of segmental lumbar movement patterns in an asymptomatic cohort, which serves as a necessary pre-requisite for identifying pathological and symptomatic deviations from the baseline.
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Affiliation(s)
- Paul McMullin
- Department of Mechanical Engineering, Brigham Young University, Provo, UT, United States
| | - Darian Emmett
- Department of Mechanical Engineering, Brigham Young University, Provo, UT, United States
| | - Andrew Gibbons
- Department of Mechanical Engineering, Brigham Young University, Provo, UT, United States
| | - Kelly Clingo
- Department of Mechanical Engineering, Brigham Young University, Provo, UT, United States
| | - Preston Higbee
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Andrew Sykes
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - David T. Fullwood
- Department of Mechanical Engineering, Brigham Young University, Provo, UT, United States
| | - Ulrike H. Mitchell
- Department of Exercise Sciences, Brigham Young University, Provo, UT, United States
| | - Anton E. Bowden
- Department of Mechanical Engineering, Brigham Young University, Provo, UT, United States
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Xu F, Zhou S, Li Z, Jiang S, Chen Z, Sun Z, Li W. The 6 degrees-of-freedom range of motion of the L1-S1 vertebrae in young and middle-aged asymptomatic people. Front Surg 2022; 9:1002133. [PMID: 36386544 PMCID: PMC9643460 DOI: 10.3389/fsurg.2022.1002133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 09/28/2022] [Indexed: 01/25/2023] Open
Abstract
STUDY DESIGN Controlled laboratory study. OBJECTIVE To determine the 6 degrees of freedom of lumbar vertebra in vivo during different functional activities in young and middle-aged asymptomatic subjects. METHODS A total of 26 asymptomatic subjects (M/F, 15/11; age, 20-55 years) were recruited in this study. They were divided into two groups: young group (number: 14; age: 20-30 years old) and middle-aged group (number: 12; age: 45-55 years old). The lumbar segment of each subject was scanned by computed tomography for the construction of three-dimensional (3D) models of the vertebra from L1 to S1. The lumbar spine was imaged by using a dual fluoroscopic system when the subjects performed different trunk postures. The 3D models of vertebrae were matched to two fluoroscopic images simultaneously in software. The range of motion (ROM) of vertebrae in the young and middle-aged groups was compared by using multiway analysis of variance, respectively. RESULTS During the supine to the upright posture, vertebral rotation of the L1-S1 occurred mainly around the mediolateral axis (mean: 3.9 ± 2.9°). Along the mediolateral axis, vertebral translation was significantly lower at L1-2 (7.7 ± 2.4 mm) and L2-3 (8.0 ± 3.5 mm) than at L3-4 (1.6 ± 1.2 mm), L4-5 (3.3 ± 2.6 mm), and L5-S1 (2.6 ± 1.9 mm). At the L4-5 level, the young group had a higher rotational ROM than the middle-aged group around all three axes during left-right bending. Along the anteroposterior axis, the young group had a lower translational ROM at L4-5 than the middle-aged group during left-right bending (4.6 ± 3.3 vs. 7.6 ± 4.8 mm; P < 0.05). At L5-S1, the young group had a lower translational ROM than the middle-aged group during flexion-extension, left-right bending, and left-right torsion. CONCLUSION This study explored the lumbar vertebral ROM at L1-S1 during different functional postures in both young and middle-aged volunteers. There were higher coupled translations at L3-4 and L4-5 than at the upper lumbar segments during supine to upright. The vertebral rotation decreased with age. In addition, the older subjects had a higher anteroposterior translation at the L4-5 segment and higher mediolateral translation at the L5-S1 segment than the young group. These data might provide basic data to be compared with spinal pathology.
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Affiliation(s)
- Fei Xu
- Orthopaedic Department, Peking University Third Hospital, Beijing, China,Peking University Health Science Center, Beijing, China,Beijing Key Laboratory of Spinal Disease Research, Beijing, China,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Siyu Zhou
- Orthopaedic Department, Peking University Third Hospital, Beijing, China,Beijing Key Laboratory of Spinal Disease Research, Beijing, China,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Zhuofu Li
- Orthopaedic Department, Peking University Third Hospital, Beijing, China,Peking University Health Science Center, Beijing, China,Beijing Key Laboratory of Spinal Disease Research, Beijing, China,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Shuai Jiang
- Orthopaedic Department, Peking University Third Hospital, Beijing, China,Beijing Key Laboratory of Spinal Disease Research, Beijing, China,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Ze Chen
- Orthopaedic Department, Peking University Third Hospital, Beijing, China,Peking University Health Science Center, Beijing, China,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Zhuoran Sun
- Orthopaedic Department, Peking University Third Hospital, Beijing, China,Beijing Key Laboratory of Spinal Disease Research, Beijing, China,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China
| | - Weishi Li
- Orthopaedic Department, Peking University Third Hospital, Beijing, China,Beijing Key Laboratory of Spinal Disease Research, Beijing, China,Engineering Research Center of Bone and Joint Precision Medicine, Ministry of Education, Beijing, China,Correspondence: Weishi Li
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Motion of Lumbar Endplate in Degenerative Lumbar Scoliosis Patients with Different Cobb Angle In Vivo: Reflecting the Biomechanics of the Lumbar Disc. BIOMED RESEARCH INTERNATIONAL 2022; 2022:8745683. [PMID: 36277876 PMCID: PMC9586789 DOI: 10.1155/2022/8745683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 08/29/2022] [Indexed: 11/18/2022]
Abstract
Study Design. Controlled laboratory study. Objective. To evaluate the influence of degenerative lumbar scoliosis (DLS) with different Cobb angles and degenerative discs on the range of motion (ROM) of the lumbar endplates during functional weight-bearing activities in vivo. Summary of Background. DLS data might influence spinal stability and range of motion of the spine. Altered lumbar segment motion is thought to be related to disc degeneration. However, to date, no data have been reported on the motion patterns of the lumbar endplates in patients with DLS in vivo. Methods. We recorded 42 DLS patients with the apical disc at L2-L3 and L3-L4. Patients were divided into A group with a coronal Cobb angle >20° (number: 13;
years old) and group B with a coronal Cobb angle <20° (number: 28;
years old). Patients’ discs were divided into a degenerated disc group (III-V) and a nondegenerated disc group (I-II) according to the Pfirrmann classification. Computed tomography (CT) was performed on every subject to build 3-dimensional (3D) models of the lumbar vertebrae (L1–S1), and then the vertebras were matched according to the dual fluoroscopic imaging system. The kinematics of the endplate was compared between the different Cobb angle groups and the healthy group reported in a previous study and between the degenerative disc group and nondegenerative disc group by multiway analysis of variance. Results. Coupled translation at L5-S1 was higher than other levels during the three movements. During the flexion-extension of the trunk, around the anteroposterior axis, rotation in group A was higher than that in the control group at L2-L3 and L3-L4 (
mm vs
mm,
mm;
,
). During the left-right bending of the trunk, around the mediolateral axis, rotations in groups A and B were higher than those in the control group at L5-S1 (
°,
° vs
°;
,
). During the left-right torsion, around the anteroposterior axis, rotation in group A was higher than that in group B and the control group at L2-3 (
° vs
°,
°;
,
). In patients with Cobb angle <20°, coupled translation was higher in the degenerated disc group than in the nondegenerated disc group, especially along the anteroposterior axis. Conclusion. An increase in the coupled rotation of the endplate at the scoliotic apical level in patients with DLS was related to a larger Cobb angle. Moreover, segments with degenerative discs had higher coupled translations in the anteroposterior direction than segments with nondegenerative discs in DLS patients with Cobb angle <20°. These data might provide clues regarding the etiology of DLS and the basis for operative planning.
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Bhattacharya S, Dubey DK. Impact of Variations in Water Concentration on the Nanomechanical Behavior of Type I Collagen Microfibrils in Annulus Fibrosus. J Biomech Eng 2022; 144:1120715. [PMID: 34820681 DOI: 10.1115/1.4052563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Indexed: 11/08/2022]
Abstract
Radial variation in water concentration from outer to inner lamellae is one of the characteristic features of annulus fibrosus (AF). In addition, water concentration changes are also associated with intervertebral disc (IVD) degeneration. Such changes alter the chemo-mechanical interactions among the biomolecular constituents at molecular level, affecting the load-bearing nature of IVD. This study investigates mechanistic impacts of water concentration on the collagen type I microfibrils in AF using molecular dynamics simulations. Results show, in axial tension, that increase in water concentration (WC) from 0% to 50% increases the elastic modulus from 2.7 GPa to 3.9 GPa. This is attributed to combination of shift in deformation from backbone straightening to combined backbone stretching- intermolecular sliding and subsequent strengthening of tropocollagen-water (TC-water-TC) interfaces through water bridges and intermolecular electrostatic attractions. Further increase in WC to 75% reduces the modulus to 1.8 GPa due to shift in deformation to polypeptide straightening and weakening of TC-water-TC interface due to reduced electrostatic attraction and increase in the number of water molecules in a water bridge. During axial compression, increase in WC to 50% results in increase in modulus from 0.8 GPa to 4.5 GPa. This is attributed to the combination of the development of hydrostatic pressure and strengthening of the TC-water-TC interface. Further increase in WC to 75% shifts load-bearing characteristic from collagen to water, resulting in a decrease in elastic modulus to 2.8 GPa. Such water-mediated alteration in load-bearing properties acts as foundations toward AF mechanics and provides insights toward understanding degeneration-mediated altered spinal stiffness.
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Affiliation(s)
- Shambo Bhattacharya
- Department of Mechanical Engineering, Indian Institute of Technology, Delhi, New Delhi 110016, India
| | - Devendra K Dubey
- Department of Mechanical Engineering, Indian Institute of Technology, Delhi, New Delhi 110016, India
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Funabashi M, Breen AC, De Carvalho D, Pagé I, Nougarou F, Descarreaux M, Kawchuk GN. Force Distribution Within Spinal Tissues During Posterior to Anterior Spinal Manipulative Therapy: A Secondary Analysis. Front Integr Neurosci 2022; 15:809372. [PMID: 35185486 PMCID: PMC8855051 DOI: 10.3389/fnint.2021.809372] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 12/31/2021] [Indexed: 12/20/2022] Open
Abstract
Background Previous studies observed that the intervertebral disc experiences the greatest forces during spinal manipulative therapy (SMT) and that the distribution of forces among spinal tissues changes as a function of the SMT parameters. However, contextualized SMT forces, relative to the ones applied to and experienced by the whole functional spinal unit, is needed to understand SMT’s underlying mechanisms. Aim To describe the percentage force distribution between spinal tissues relative to the applied SMT forces and total force experienced by the functional unit. Methods This secondary analysis combined data from 35 fresh porcine cadavers exposed to a simulated 300N SMT to the skin overlying the L3/L4 facet joint via servo-controlled linear motor actuator. Vertebral kinematics were tracked optically using indwelling bone pins. The functional spinal unit was then removed and mounted on a parallel robotic platform equipped with a 6-axis load cell. The kinematics of the spine during SMT were replayed by the robotic platform. By using serial dissection, peak and mean forces induced by the simulated SMT experienced by spinal structures in all three axes of motion were recorded. Forces experienced by spinal structures were analyzed descriptively and the resultant force magnitude was calculated. Results During SMT, the functional spinal unit experienced a median peak resultant force of 36.4N (IQR: 14.1N) and a mean resultant force of 25.4N (IQR: 11.9N). Peak resultant force experienced by the spinal segment corresponded to 12.1% of the total applied SMT force (300N). When the resultant force experienced by the functional spinal unit was considered to be 100%, the supra and interspinous ligaments experienced 0.3% of the peak forces and 0.5% of the mean forces. Facet joints and ligamentum flavum experienced 0.7% of the peak forces and 3% of the mean forces. Intervertebral disc and longitudinal ligaments experienced 99% of the peak and 96.5% of the mean forces. Conclusion In this animal model, a small percentage of the forces applied during a posterior-to-anterior SMT reached spinal structures in the lumbar spine. Most SMT forces (over 96%) are experienced by the intervertebral disc. This study provides a novel perspective on SMT force distribution within spinal tissues.
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Affiliation(s)
- Martha Funabashi
- Division of Research and Innovation, Canadian Memorial Chiropractic College, Toronto, ON, Canada
- Chiropractic Department, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
- *Correspondence: Martha Funabashi,
| | | | - Diana De Carvalho
- Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL, Canada
| | - Isabelle Pagé
- Chiropractic Department, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
| | - François Nougarou
- Department of Electrical and Computer Engineering, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
| | - Martin Descarreaux
- Human Kinetics Department, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada
| | - Gregory N. Kawchuk
- Department of Physical Therapy, University of Alberta, Edmonton, AB, Canada
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Li Z, Chen DJ, Liu Z, Tang B, Zhong Y, Li G, Wan Z. Motion characteristics of the lower lumbar spine in individuals with different pelvic incidence: An in vivo biomechanical study. Clin Biomech (Bristol, Avon) 2021; 88:105419. [PMID: 34303068 DOI: 10.1016/j.clinbiomech.2021.105419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 06/20/2021] [Accepted: 06/23/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND Pelvic incidence is the quantification of the pelvis anatomical shape which has significant effect on the occurrence of various lumbar degenerative diseases. The aim of this study was to measure the in vivo dynamic motion characteristics of the lower lumbar spine in people with different pelvic incidence. METHODS A total of 55 volunteers were included in the study. The participants were devided into 3 groups (A: pelvic incidence≤40°, B: 40° < pelvic incidence <60° and C: pelvic incidence ≥60°). The L3-S1 vertebrae of each subject was MRI scanned to construct 3D models. The lumbar spine was then imaged using a dual fluoroscopic imaging system as the subject performed physiological position. The 3D vertebral models and the fluoroscopic images were used to reproduce the in vivo vertebral positions along the motion path. The relative translations and rotations of each motion segment were analyzed. FINDINGS At the L5-S1 segment, the primary ranges of motion for left-right axial rotation and flexion-extension of the patients with large pelvic incidence (3.28° ± 0.79°, 7.56° ± 1.81°) were significantly larger than normal pelvic incidence (2.61° ± 1.01°, 6.57° ± 2.18°) and small pelvic incidence (2.00° ± 0.60°, 5.83° ± 1.67°). INTERPRETATION The anatomic variable pelvic incidence is associated with the ranges of motion in lower lumbar vertebrae, especially in the L4-5 and L5-S1 segments.
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Affiliation(s)
- Zhiyun Li
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi, PR China
| | - De-Jian Chen
- Department of Orthopedics, The Affiliated Nanjing Jiangbei Hospital of Nantong University, Nanjing, Jiangsu 210048, PR China
| | - Zhang Liu
- The First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi, PR China
| | - Benyu Tang
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi, PR China
| | - Yanlong Zhong
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi, PR China
| | - Guoan Li
- Bioengineering Lab, Department of Orthopaedic Surgery, Massachusetts General Hospital/Harvard Medical School, 55 Fruit St., GRJ 1215, Boston, MA 02114, USA.
| | - Zongmiao Wan
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, Nanchang 330006, Jiangxi, PR China.
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Yin J, Liu Z, Li C, Luo S, Lai Q, Wang S, Zhang B, Wan Z. Effect of facet-joint degeneration on the in vivo motion of the lower lumbar spine. J Orthop Surg Res 2020; 15:340. [PMID: 32819395 PMCID: PMC7439653 DOI: 10.1186/s13018-020-01826-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 07/29/2020] [Indexed: 11/10/2022] Open
Abstract
Objective This research studied the in vivo motion characteristics of the L3–S1 lumbar spine with facet-joint degeneration during functional activities. Methods Thirteen male and 21 female patients with facet-joint degeneration at the L3–S1 spinal region were included in the study. The L3–S1 lumbar segments of all the patients were divided into 3 groups according to the degree of facet-joints degeneration (mild, moderate, or severe). The ranges of motion (ROM) of the vertebrae were analyzed using a combination of computed tomography and dual fluoroscopic imaging techniques. During functional postures, the ROMs were compared between the 3 groups at each spinal level (L3–L4, L4–L5, and L5–S1). Results At L3–L4 level, the primary rotations between the mild and moderate groups during left-right twisting activity were significantly different. At L4–L5 level, the primary rotation of the moderate group was significantly higher than the other groups during flexion-extension. During left-right bending activities, a significant difference was observed only between the moderate and severe groups. At L5–S1 level, the rotation of the moderate group was significantly higher than the mild group during left-right bending activity. Conclusions Degeneration of the facet joint alters the ROMs of the lumbar spine. As the degree of facet-joint degeneration increased, the ROMs of the lumbar vertebra that had initially increased declined. However, when there was severe facet-joint degeneration, the ROMs of the lumbar spine declined to levels comparative to the moderate group. The relationship between the stability of the lumbar vertebra and the degree of facet-joint degeneration requires further study.
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Affiliation(s)
- Jun Yin
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, Jiangxi, 330006, PR China
| | - Zhang Liu
- Science and Technology Office, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, PR China
| | - Chao Li
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, Jiangxi, 330006, PR China
| | - Shiwei Luo
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, Jiangxi, 330006, PR China
| | - Qi Lai
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, Jiangxi, 330006, PR China
| | - Shaobai Wang
- Key Laboratory of Exercise and Health Sciences of Ministry of Education, School of Kinesiology, Shanghai University of Sport, Shanghai, China
| | - Bin Zhang
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, Jiangxi, 330006, PR China
| | - Zongmiao Wan
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, Jiangxi, 330006, PR China.
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Investigation of Alterations in the Lumbar Disc Biomechanics at the Adjacent Segments After Spinal Fusion Using a Combined In Vivo and In Silico Approach. Ann Biomed Eng 2020; 49:601-616. [PMID: 32785861 DOI: 10.1007/s10439-020-02588-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 07/31/2020] [Indexed: 12/15/2022]
Abstract
The development of adjacent segment degeneration (ASD) is a major concern after lumbar spinal fusion surgery, but the causative mechanisms remain unclear. This study used a combined in vivo and in silico method to investigate the changes of anatomical dimensions and biomechanical responses of the adjacent segment (L3-4) after spinal fusion (L4-S1) in five patients under weight-bearing upright standing conditions. The in vivo adjacent disc height changes before and after fusion were measured using a dual fluoroscopic imaging system (DFIS), and the measured in vivo intervertebral positions and orientations were used as displacement boundary conditions of the patient-specific three-dimensional (3D) finite element (FE) disc models to simulate the biomechanical responses of adjacent discs to fusion of the diseased segments. Our data (represented by medians and 95% confidence intervals) showed that a significant decrease by - 0.8 (- 1.2, - 0.4) mm (p < 0.05) in the adjacent disc heights occurred at the posterior region after fusion. The significant increases in disc tissue strains and stresses, 0.32 (0.21, 0.43) mm/mm (p < 0.05) and 1.70 (1.07, 3.60) MPa (p < 0.05), respectively, after fusion were found in the posterolateral portions of the outermost annular lamella. The intradiscal pressure of the adjacent disc was significantly increased by 0.29 (0.13, 0.47) MPa after fusion (p < 0.05). This study demonstrated that fusion could cause alterations in adjacent disc biomechanics, and the combined in vivo and in silico method could be a valuable tool for the quantitative assessment of ASD after fusion.
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Natarajan RN, Watanabe K, Hasegawa K. Posterior bone graft in lumbar spine surgery reduces the stress in the screw-rod system- A finite element study. J Mech Behav Biomed Mater 2020; 104:103628. [PMID: 31929096 DOI: 10.1016/j.jmbbm.2020.103628] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/03/2020] [Accepted: 01/07/2020] [Indexed: 10/25/2022]
Abstract
PURPOSE Analyze the biomechanical effect of postero-lateral instrumentation with and without posterior bone graft as well as effect of consolidation of the graft. Study objectives are (1) whether bone graft alone will provide enough additional strength to the weakened spine, (2) how the addition of posterior bone graft help in extending the life of the fusion construct, and (3) compare the effect of gradual consolidation of the bone-graft on the spine biomechanics. METHODS A lumbar spine finite element model was used to analyze the effects of bone-graft alone and varying grades of bone-graft consolidation with postero-lateral instrumentation on spine biomechanics. The spine stiffness and stresses in the posterior rods and screws were determined for moments applied in the three physiological directions in addition to pre-load. RESULTS Stiffness of a normal lumbar spine with a solid consolidated posterior bone graft was found to be 10 times that of an intact lumbar spine. Posterior instrumentation further increased the spine stiffness by 20 fold. A 50% solid consolidation of the graft reduced the screw-rod maximum von-Mises stress by 45% and a 65% reduction in screw-rod stress was calculated with completely fused graft. CONCLUSION A fused graft with posterior instrumentation provided a 200 fold increase in stiffness of an intact spine while producing stress shielding to the Ti rod-screw system. Considerable reduction of the maximum von-Mises stresses in the postero-lateral rod and screw fusion system (65%) will contribute to prevention of implant failure under repetitive loading highlighting the importance of consolidation of posterior bone-graft.
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Affiliation(s)
- Raghu N Natarajan
- Rush University Medical Center, Suite 204 F, Orthopedic Ambulatory Building, 1611 West Harrison, Chicago, IL, 60612, USA.
| | - Kei Watanabe
- Niigata University Medical and Dental General Hospital, Niigata, Japan
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Zhou C, Wang H, Wang C, Tsai TY, Yu Y, Ostergaard P, Li G, Cha T. Intervertebral range of motion characteristics of normal cervical spinal segments (C0-T1) during in vivo neck motions. J Biomech 2019; 98:109418. [PMID: 31653508 DOI: 10.1016/j.jbiomech.2019.109418] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Revised: 09/24/2019] [Accepted: 10/13/2019] [Indexed: 01/19/2023]
Abstract
The in vivo intervertebral range of motion (ROM) is an important predictor for spinal disorders. While the subaxial cervical spine has been extensively studied, the motion characteristics of the occipito-atlantal (C0-1) and atlanto-axial (C1-2) cervical segments were less reported due to technical difficulties in accurate imaging of these two segments. In this study, we investigated the intervertebral ROMs of the entire cervical spine (C0-T1) during in vivo functional neck motions of asymptomatic human subjects, including maximal flexion-extension, left-right lateral bending, and left-right axial torsion, using previously validated dual fluoroscopic imaging and model registration techniques. During all neck motions, C0-1, similar to C7-T1, was substantially less mobile than other segments and always contributed less than 10% of the cervical rotations. During the axial rotation of the neck, C1-2 contributed 73.2 ± 17.3% of the cervical rotation, but each of other segments contributed less than 10% of the cervical rotation. During both lateral bending and axial torsion neck motions, regardless of primary or coupled motions, the axial torsion ROM of C1-2 was significantly greater than its lateral bending ROM (p < 0.001), whereas the opposite differences were consistently observed at subaxial segments. This study reveals that there are distinct motion patterns at upper and lower cervical segments during in vivo neck motions. The reported data could be useful for the development of new diagnosis methods of cervical pathologies and new surgical techniques that aim to restore normal cervical segmental motion.
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Affiliation(s)
- Chaochao Zhou
- Orthopaedic Bioengineering Research Center, Newton-Wellesley Hospital, Harvard Medical School, Newton, MA, USA; Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Haiming Wang
- Orthopaedic Bioengineering Research Center, Newton-Wellesley Hospital, Harvard Medical School, Newton, MA, USA; Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Spinal Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Cong Wang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Tsung-Yuan Tsai
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.
| | - Yan Yu
- Orthopaedic Bioengineering Research Center, Newton-Wellesley Hospital, Harvard Medical School, Newton, MA, USA; Department of Spine Surgery, Tongji Hospital, Tongji University School of Medicine, Shanghai, China
| | - Peter Ostergaard
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Guoan Li
- Orthopaedic Bioengineering Research Center, Newton-Wellesley Hospital, Harvard Medical School, Newton, MA, USA.
| | - Thomas Cha
- Orthopaedic Bioengineering Research Center, Newton-Wellesley Hospital, Harvard Medical School, Newton, MA, USA; Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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Koo TK, Crews RL, Kwok WE. In Vivo Measurement of the Human Lumbar Spine Using Magnetic Resonance Imaging to Ultrasound Registration. J Manipulative Physiol Ther 2019; 42:343-352. [PMID: 31255312 DOI: 10.1016/j.jmpt.2019.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 03/08/2019] [Accepted: 03/30/2019] [Indexed: 11/18/2022]
Abstract
OBJECTIVE This study aimed to refine a magnetic resonance imaging (MRI)-ultrasound registration (ie, alignment) technique to make noninvasive, nonionizing, 3-dimensional measurement of the lumbar segmental motion in vivo. METHODS Five healthy participants participated in this validation study. We scanned the lumbar region of each participant 5 times using an ultrasound probe while he or she kept a prone lying posture on a plinth. Participant-specific models of L1-L5 were constructed from magnetic resonance (MR) images and aligned with the 3-dimensional ultrasound dataset of each scan using 4 variants of MRI-ultrasound registration approach (simplified intensity-based registration [1] with and [2] without including the transverse processes and their surrounding soft tissues [denoted as TP complex]; and hierarchical intensity-based registration [3] with and [4] without including the TP complex). The robustness and precision of these registration approaches were compared. RESULTS Although all registration approaches converged to a similar solution, excluding the TP complex improved the percentage of successful registration from 92% to 100%. There was no significant difference in the precision among the 4 MRI-ultrasound registration variants. For the simplified intensity-based registration without including the TP complex, average precision at each degree of freedom was 1.33° (flexion-extension), 2.48° (lateral bending), 1.32° (axial rotation), 2.15 mm (left/right), 1.08 mm (anterior-posterior), and 1.16 (superior-inferior), respectively. CONCLUSION Given that using simplified intensity-based MRI-ultrasound registration can substantially streamline the registration process and excluding the TP complex would improve the robustness of the registration, we conclude that this combination is the method of choice for in vivo human applications.
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Affiliation(s)
- Terry K Koo
- Foot Levelers Biomechanics Research Laboratory, New York Chiropractic College, Seneca, Falls, NY.
| | - Robert L Crews
- Foot Levelers Biomechanics Research Laboratory, New York Chiropractic College, Seneca, Falls, NY
| | - Wingchi E Kwok
- Department of Imaging Sciences, University of Rochester, University of Rochester Center for Advanced Brain Imaging & Neurophysiology, Rochester, NY
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Nie T, Chen DJ, Tang B, Song Q, Liu X, Zhang B, Dai M, Li G, Wan Z. In vivo dynamic motion characteristics of the lower lumbar spine: L4-5 lumbar degenerative disc diseases undergoing unilateral or bilateral pedicle screw fixation combined with TLIF. J Orthop Surg Res 2019; 14:171. [PMID: 31174560 PMCID: PMC6555927 DOI: 10.1186/s13018-019-1198-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 05/15/2019] [Indexed: 01/03/2023] Open
Abstract
Objective To evaluate the short-term in vivo dynamic motion characteristics of the lower lumbar spine (L3–S1) after unilateral pedicle screw fixation (UPSF) or bilateral pedicle screw fixation (BPSF) combined with TLIF for treatment of L4–5 lumbar degenerative disc diseases (DDD). Methods Twenty-eight patients were recruited (13 UPSF, 15 BPSF). Each patient was CT-scanned to construct 3D models of the L3–S1 vertebrae. The dual fluoroscopic imaging system (DFIS) was then used to image the lumbar spine while the patient performed seven functional activities (upright standing, maximum extension, flexion, left–right twist, and left–right bend). The in vivo vertebral positions were reproduced using the 3D vertebral models and DFIS images. The ranges of motion (ROMs) of L3–4, L4–5, and L5–S1 segments were analyzed. Results At the index L4–5 segment, the primary ROM of left–right twist of the UPSF group (2.11 ± 0.52°) was significantly larger (p = 0.000) than the BPSF group (0.73 ± 0.32°). At the proximal adjacent L3–4 segment, the primary ROMs of left–right twist, and left–right bend of the UPSF group (2.16 ± 0.73°, 2.28 ± 1.03°) were significantly less (p = 0.003, 0.023) than the BPSF group (3.17 ± 0.88, 3.12 ± 1.04°), respectively. However, at distal adjacent L5–S1 segment, no significant difference was found between the two groups during all activities. Conclusions The ROM in left–right twisting of UPSF group was significantly larger compared with BPSF group at the index level in the short term. The UPSF has less impact on the cranial adjacent level (L3–4) in left–right twisting and bending activities compared to the BPSF. The data implied that the UPSE and BPSF combined with TLIF would result in different biomechanics in the index and cranial adjacent segment biomechanics. Long-term follow-up studies are necessary to compare the clinical outcomes of the two surgeries. Electronic supplementary material The online version of this article (10.1186/s13018-019-1198-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tao Nie
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, 330006, Jiangxi, People's Republic of China
| | - De-Jian Chen
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Benyu Tang
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Quanwei Song
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Xuqiang Liu
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Bin Zhang
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Min Dai
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, 330006, Jiangxi, People's Republic of China
| | - Guoan Li
- Bioengineering Lab, Department of Orthopaedic Surgery, Massachusetts General Hospital/Harvard Medical School, 55 Fruit St., GRJ 1215, Boston, MA, 02114, USA
| | - Zongmiao Wan
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, 17 Yongwai Street, Nanchang, 330006, Jiangxi, People's Republic of China.
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Berry DB, Hernandez A, Onodera K, Ingram N, Ward SR, Gombatto SP. Lumbar spine angles and intervertebral disc characteristics with end-range positions in three planes of motion in healthy people using upright MRI. J Biomech 2019; 89:95-104. [PMID: 31047693 DOI: 10.1016/j.jbiomech.2019.04.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 04/02/2019] [Accepted: 04/12/2019] [Indexed: 12/17/2022]
Abstract
Understanding changes in lumbar spine (LS) angles and intervertebral disc (IVD) behavior in end-range positions in healthy subjects can provide a basis for developing more specific LS models and comparing people with spine pathology. The purposes of this study are to quantify 3D LS angles and changes in IVD characteristics with end-range positions in 3 planes of motion using upright MRI in healthy people, and to determine which intervertebral segments contribute most in each plane of movement. Thirteen people (average age = 24.4 years, range 18-51 years; 9 females; BMI = 22.4 ± 1.8 kg/m2) with no history of low back pain were scanned in an upright MRI in standing, sitting flexion, sitting axial rotation (left, right), prone on elbows, prone extension, and standing lateral bending (left, right). Global and local intervertebral LS angles were measured. Anterior-posterior length of the IVD and location of the nucleus pulposus was measured. For the sagittal plane, lower LS segments contribute most to change in position, and the location of the nucleus pulposus migrated from a more posterior position in sitting flexion to a more anterior position in end-range extension. For lateral bending, the upper LS contributes most to end-range positions. Small degrees of intervertebral rotation (1-2°) across all levels were observed for axial plane positions. There were no systematic changes in IVD characteristics for axial or coronal plane positions.
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Affiliation(s)
- David B Berry
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Alejandra Hernandez
- Doctor of Physical Therapy Program, School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA, USA
| | - Keenan Onodera
- Department of Orthopaedic Surgery, University of California San Diego, La Jolla, CA, USA
| | - Noah Ingram
- Doctor of Physical Therapy Program, School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA, USA
| | - Samuel R Ward
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA; Department of Orthopaedic Surgery, University of California San Diego, La Jolla, CA, USA; Department of Radiology, University of California San Diego, La Jolla, CA, USA
| | - Sara P Gombatto
- Doctor of Physical Therapy Program, School of Exercise and Nutritional Sciences, San Diego State University, San Diego, CA, USA.
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Kinematics of the Spine Under Healthy and Degenerative Conditions: A Systematic Review. Ann Biomed Eng 2019; 47:1491-1522. [DOI: 10.1007/s10439-019-02252-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 03/21/2019] [Indexed: 01/05/2023]
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Axial loading during MRI reveals deviant characteristics within posterior IVD regions between low back pain patients and controls. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2018; 27:2840-2846. [PMID: 30302541 DOI: 10.1007/s00586-018-5774-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 08/27/2018] [Accepted: 09/19/2018] [Indexed: 12/14/2022]
Abstract
PURPOSE To investigate differences in functional intervertebral disk (IVD) characteristics between low back pain (LBP) patients and controls using T2-mapping with axial loading during MRI (alMRI). METHODS In total, 120 IVDs in 24 LBP patients (mean age 39 years, range 25-69) were examined with T2-mapping without loading of the spine (uMRI) and with alMRI (DynaWell® loading device) and compared with 60 IVDs in 12 controls (mean age 38 years, range 25-63). The IVD T2-value was acquired after 20-min loading in five regions of interests (ROI), ROI1-5 from anterior to posterior. T2-values were compared between loading states and cohorts with adjustment for Pfirrmann grade. RESULTS In LBP patients, mean T2-value of the entire IVD was 64 ms for uMRI and 66 ms for alMRI (p = 0.03) and, in controls, 65 ms and 65 ms (p = 0.5). Load-induced T2-differences (alMRI-uMRI) were seen in all ROIs in both patients (0.001 > p < 0.005) and controls (0.0001 > p < 0.03). In patients, alMRI induced an increase in T2-value for ROI1-3 (23%, 18% and 5%) and a decrease for ROI4 (3%) and ROI5 (24%). More pronounced load-induced decrease was detected in ROI4 in controls (9%/p = 0.03), while a higher absolute T2-value was found for ROI5 during alMRI in patients (38 ms) compared to controls (33 ms) (p = 0.04). CONCLUSION The alMRI-induced differences in T2-value in ROI4 and ROI5 between patients and controls most probably indicate biomechanical impairment in the posterior IVD regions. Hence, alMRI combined with T2-mapping offers an objective and clinical feasible tool for biomechanical IVD characterization that may deepen the knowledge regarding how LBP is related to altered IVD matrix composition. These slides can be retrieved under Electronic Supplementary Material.
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Natarajan RN, Watanabe K, Hasegawa K. Biomechanical Analysis of a Long-Segment Fusion in a Lumbar Spine—A Finite Element Model Study. J Biomech Eng 2018; 140:2679248. [PMID: 29801167 DOI: 10.1115/1.4039989] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Indexed: 11/08/2022]
Abstract
Examine the biomechanical effect of material properties, geometric variables, and anchoring arrangements in a segmental pedicle screw with connecting rods spanning the entire lumbar spine using finite element models (FEMs). The objectives of this study are (1) to understand how different variables associated with posterior instrumentation affect the lumbar spine kinematics and stresses in instrumentation, (2) to compare the multidirectional stability of the spinal instrumentation, and (3) to determine how these variables contribute to the rigidity of the long-segment fusion in a lumbar spine. A lumbar spine FEM was used to analyze the biomechanical effects of different materials used for spinal rods (TNTZ or Ti or CoCr), varying diameters of the screws and rods (5 mm and 6 mm), and different fixation techniques (multilevel or intermittent). The results based on the range of motion and stress distribution in the rods and screws revealed that differences in properties and variations in geometry of the screw-rod moderately affect the biomechanics of the spine. Further, the spinal screw-rod system was least stable under the lateral bending mode. Stress analyzes of the screws and rods revealed that the caudal section of the posterior spinal instrumentation was more susceptible to high stresses and hence possible failure. Although CoCr screws and rods provided the greatest spinal stabilization, these constructs were susceptible to fatigue failure. The findings of the present study suggest that a posterior instrumentation system with a 5-mm screw-rod diameter made of Ti or TNTZ is advantageous over CoCr instrumentation system.
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Affiliation(s)
- Raghu N. Natarajan
- Rush University Medical Center, Suite 204 F, Orthopedic Ambulatory Building, 1611 West Harrison, Chicago, IL 60612 e-mail:
| | - Kei Watanabe
- Department of Orthopaedic Surgery, Niigata University Medical and Dental General Hospital, 1-757, Asahimachidori, Chuoku, Niigata City, Niigata 951-8510, Japan e-mail:
| | - Kazuhiro Hasegawa
- Niigata Spine Surgery Center, 2-5-22 Nishi-machi, Konan-ku, Niigata 950-0165, Japan e-mail:
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Bezci SE, Eleswarapu A, Klineberg EO, O'Connell GD. Contribution of facet joints, axial compression, and composition to human lumbar disc torsion mechanics. J Orthop Res 2018; 36:2266-2273. [PMID: 29431237 DOI: 10.1002/jor.23870] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 01/24/2018] [Indexed: 02/04/2023]
Abstract
Stresses applied to the spinal column are distributed between the intervertebral disc and facet joints. Structural and compositional changes alter stress distributions within the disc and between the disc and facet joints. These changes influence the mechanical properties of the disc joint, including its stiffness, range of motion, and energy absorption under quasi-static and dynamic loads. There have been few studies evaluating the role of facet joints in torsion. Furthermore, the relationship between biochemical composition and torsion mechanics is not well understood. Therefore, the first objective of this study was to investigate the role of facet joints in torsion mechanics of healthy and degenerated human lumbar discs under a wide range of compressive preloads. To achieve this, each disc was tested under four different compressive preloads (300-1200 N) with and without facet joints. The second objective was to develop a quantitative structure-function relationship between tissue composition and torsion mechanics. Facet joints have a significant contribution to disc torsional stiffness (∼60%) and viscoelasticity, regardless of the magnitude of axial compression. The findings from this study demonstrate that annulus fibrosus GAG content plays an important role in disc torsion mechanics. A decrease in GAG content with degeneration reduced torsion mechanics by more than an order of magnitude, while collagen content did not significantly influence disc torsion mechanics. The biochemical-mechanical and compression-torsion relationships reported in this study allow for better comparison between studies that use discs of varying levels of degeneration or testing protocols and provide important design criteria for biological repair strategies. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.
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Affiliation(s)
- Semih E Bezci
- Department of Mechanical Engineering, University of California Berkeley, Etcheverry Hall, Berkeley, California 94720
| | - Ananth Eleswarapu
- Department of Orthopaedic Surgery, University of California Davis, Medical Center, Sacramento, California 95817
| | - Eric O Klineberg
- Department of Orthopaedic Surgery, University of California Davis, Medical Center, Sacramento, California 95817
| | - Grace D O'Connell
- Department of Mechanical Engineering, University of California Berkeley, Etcheverry Hall, Berkeley, California 94720
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Sabnis AB, Chamoli U, Diwan AD. Is L5-S1 motion segment different from the rest? A radiographic kinematic assessment of 72 patients with chronic low back pain. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2017; 27:1127-1135. [PMID: 29181575 DOI: 10.1007/s00586-017-5400-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Revised: 11/17/2017] [Accepted: 11/18/2017] [Indexed: 11/24/2022]
Abstract
PURPOSE The relationship between biomechanical instability and degenerative changes in the lumbar spine in chronic low back pain (CLBP) patients remains controversial. The main objective of this retrospective radiographical study was to evaluate changes in kinematics at different lumbar levels (in particular the L5-S1 level) with progressive grades of disc degeneration and facet joint osteoarthritis in CLBP patients. METHODS Using standing neutral and dynamic flexion/extension (Fx/Ex) radiographs of the lumbar spine, in vivo segmental kinematics at L1-L2 through L5-S1 were evaluated in 72 consecutive CLBP patients. Disc degeneration was quantified using changes in signal intensity and central disc height on mid-sagittal T2-weighted magnetic resonance (MR) scans. Additionally, the presence or absence of facet joint osteoarthritis was noted on T2-weighted axial MR scans. RESULTS Disc degeneration and facet joint osteoarthritis occurred independent of each other at the L5-S1 level (p = 0.188), but an association was observed between the two at L4-L5 (p < 0.001) and L3-L4 (p < 0.05) levels. In the absence of facet joint osteoarthritis, the L5-S1 segment showed a greater range of motion (ROM) in Ex (3.3° ± 3.6°) and a smaller ROM in Fx (0.6° ± 4.2°) compared with the upper lumbar levels (p < 0.05), but the differences diminished in the presence of it. In the absence of facet joint osteoarthritis, no change in L5-S1 kinematics was observed with progressive disc degeneration, but in its presence, restabilisation of the L5-S1 segment was observed between mild and severe disc degeneration states. CONCLUSION The L5-S1 motion segment exhibited unique degenerative and kinematic characteristics compared with the upper lumbar motion segments. Disc degeneration and facet joint osteoarthritis occurred independent of each other at the L5-S1 level, but not at the other lumbar levels. Severe disc degeneration in the presence of facet joint osteoarthritis biomechanically restabilised the L5-S1 motion segment.
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Affiliation(s)
- Ashutosh B Sabnis
- Spine Service, Department of Orthopaedic Surgery, St. George & Sutherland Clinical School, University of New South Wales, Kogarah, Sydney, NSW, 2217, Australia
| | - Uphar Chamoli
- Spine Service, Department of Orthopaedic Surgery, St. George & Sutherland Clinical School, University of New South Wales, Kogarah, Sydney, NSW, 2217, Australia.
| | - Ashish D Diwan
- Spine Service, Department of Orthopaedic Surgery, St. George & Sutherland Clinical School, University of New South Wales, Kogarah, Sydney, NSW, 2217, Australia
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Breen A, Breen A. Uneven intervertebral motion sharing is related to disc degeneration and is greater in patients with chronic, non-specific low back pain: an in vivo, cross-sectional cohort comparison of intervertebral dynamics using quantitative fluoroscopy. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2017; 27:145-153. [PMID: 28555313 DOI: 10.1007/s00586-017-5155-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 04/03/2017] [Accepted: 05/24/2017] [Indexed: 12/13/2022]
Abstract
PURPOSE Evidence of intervertebral mechanical markers in chronic, non-specific low back pain (CNSLBP) is lacking. This research used dynamic fluoroscopic studies to compare intervertebral angular motion sharing inequality and variability (MSI and MSV) during continuous lumbar motion in CNSLBP patients and controls. Passive recumbent and active standing protocols were used and the relationships of these variables to age and disc degeneration were assessed. METHODS Twenty patients with CNSLBP and 20 matched controls received quantitative fluoroscopic lumbar spine examinations using a standardised protocol for data collection and image analysis. Composite disc degeneration (CDD) scores comprising the sum of Kellgren and Lawrence grades from L2-S1 were obtained. Indices of intervertebral motion sharing inequality (MSI) and variability (MSV) were derived and expressed in units of proportion of lumbar range of motion from outward and return motion sequences during lying (passive) and standing (active) lumbar bending and compared between patients and controls. Relationships between MSI, MSV, age and CDD were assessed by linear correlation. RESULTS MSI was significantly greater in the patients throughout the intervertebral motion sequences of recumbent flexion (0.29 vs. 0.22, p = 0.02) and when flexion, extension, left and right motion were combined to give a composite measure (1.40 vs. 0.92, p = 0.04). MSI correlated substantially with age (R = 0.85, p = 0.004) and CDD (R = 0.70, p = 0.03) in lying passive investigations in patients and not in controls. There were also substantial correlations between MSV and age (R = 0.77, p = 0.01) and CDD (R = 0.85, p = 0.004) in standing flexion in patients and not in controls. CONCLUSION Greater inequality and variability of motion sharing was found in patients with CNSLBP than in controls, confirming previous studies and suggesting a biomechanical marker for the disorder at intervertebral level. The relationship between disc degeneration and MSI was augmented in patients, but not in controls during passive motion and similarly for MSV during active motion, suggesting links between in vivo disc mechanics and pain generation.
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Affiliation(s)
- Alan Breen
- Faculty of Science and Technology, Bournemouth University, Poole, BH12 5BB, UK.
| | - Alexander Breen
- Institute for Musculoskeletal Research and Clinical Implementation, Anglo-European College of Chiropractic, Bournemouth, BH5 2DF, UK
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Eskandari A, Arjmand N, Shirazi-Adl A, Farahmand F. Subject-specific 2D/3D image registration and kinematics-driven musculoskeletal model of the spine. J Biomech 2017; 57:18-26. [DOI: 10.1016/j.jbiomech.2017.03.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 03/12/2017] [Accepted: 03/13/2017] [Indexed: 11/26/2022]
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Aiyangar A, Zheng L, Anderst W, Zhang X. Instantaneous centers of rotation for lumbar segmental extension in vivo. J Biomech 2017; 52:113-121. [DOI: 10.1016/j.jbiomech.2016.12.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 12/14/2016] [Accepted: 12/19/2016] [Indexed: 10/20/2022]
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Natarajan RN, Andersson GBJ. Lumbar disc degeneration is an equally important risk factor as lumbar fusion for causing adjacent segment disc disease. J Orthop Res 2017; 35:123-130. [PMID: 27152925 DOI: 10.1002/jor.23283] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 04/29/2016] [Indexed: 02/04/2023]
Abstract
Treatment of degenerative spinal disorders by fusion produces abnormal mechanical conditions at mobile segments above or below the site of spinal disorders and is clinically referred to as adjacent segments disc disease (ASDD) or transition syndrome in the case of a previous surgical treatment. The aim of the current study is to understand with the help of poro-elastic finite element models how single or two level degeneration of lower lumbar levels influences motions at adjacent levels and compare the findings to motions produced by single or two level fusions when the adjacent disk has varying degree of degeneration. Validated grade-specific finite element models including varying grades of disc degeneration at lower lumbar levels with and without fusion were developed and used to determine motions at all levels of the lumbar spine due to applied moment loads. Results showed that adjacent disc motions do depend on severity of disc degeneration, number of disc degenerated or fused, and level at which degeneration or fusion occurred. Furthermore, single level degeneration and single level fusion produced similar amount of adjacent disc motions. The pattern of increase in adjacent segment motions due to disc degeneration and increase in motions at segment adjacent to fusion was similar. Based on the current study, it can be concluded that disc degeneration should also be considered as a risk factor in addition to fusion for generating adjacent disc degeneration. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:123-130, 2017.
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Affiliation(s)
- Raghu N Natarajan
- Department of Orthopedic Surgery, Rush University Medical Center, 1611 West Harrison Street, Chicago 60612-3833, Illinois
| | - Gunnar B J Andersson
- Department of Orthopedic Surgery, Rush University Medical Center, 1611 West Harrison Street, Chicago 60612-3833, Illinois
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Mahato NK, Montuelle S, Goubeaux C, Cotton J, Williams S, Thomas J, Clark BC. Quantification of intervertebral displacement with a novel MRI-based modeling technique: Assessing measurement bias and reliability with a porcine spine model. Magn Reson Imaging 2016; 38:77-86. [PMID: 28027908 DOI: 10.1016/j.mri.2016.12.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 12/21/2016] [Accepted: 12/22/2016] [Indexed: 11/26/2022]
Abstract
The purpose of this study was to develop a novel magnetic resonance imaging (MRI)-based modeling technique for measuring intervertebral displacements. Here, we present the measurement bias and reliability of the developmental work using a porcine spine model. Porcine lumbar vertebral segments were fitted in a custom-built apparatus placed within an externally calibrated imaging volume of an open-MRI scanner. The apparatus allowed movement of the vertebrae through pre-assigned magnitudes of sagittal and coronal translation and rotation. The induced displacements were imaged with static (T1) and fast dynamic (2D HYCE S) pulse sequences. These images were imported into animation software, in which these images formed a background 'scene'. Three-dimensional models of vertebrae were created using static axial scans from the specimen and then transferred into the animation environment. In the animation environment, the user manually moved the models (rotoscoping) to perform model-to-'scene' matching to fit the models to their image silhouettes and assigned anatomical joint axes to the motion-segments. The animation protocol quantified the experimental translation and rotation displacements between the vertebral models. Accuracy of the technique was calculated as 'bias' using a linear mixed effects model, average percentage error and root mean square errors. Between-session reliability was examined by computing intra-class correlation coefficients (ICC) and the coefficient of variations (CV). For translation trials, a constant bias (β0) of 0.35 (±0.11) mm was detected for the 2D HYCE S sequence (p=0.01). The model did not demonstrate significant additional bias with each mm increase in experimental translation (β1Displacement=0.01mm; p=0.69). Using the T1 sequence for the same assessments did not significantly change the bias (p>0.05). ICC values for the T1 and 2D HYCE S pulse sequences were 0.98 and 0.97, respectively. For rotation trials, a constant bias (β0) of 0.62 (±0.12)° was detected for the 2D HYCE S sequence (p<0.01). The model also demonstrated an additional bias (β1Displacement) of 0.05° with each degree increase in the experimental rotation (p<0.01). Using T1 sequence for the same assessments did not significantly change the bias (p>0.05). ICC values for the T1 and 2D HYCE S pulse sequences were recorded 0.97 and 0.91, respectively. This novel quasi-static approach to quantifying intervertebral relationship demonstrates a reasonable degree of accuracy and reliability using the model-to-image matching technique with both static and dynamic sequences in a porcine model. Future work is required to explore multi-planar assessment of real-time spine motion and to examine the reliability of our approach in humans.
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Affiliation(s)
- Niladri K Mahato
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Biomedical Sciences, Ohio University, Athens, OH 45701, United States.
| | - Stephane Montuelle
- Department of Biomedical Sciences, Ohio University, Athens, OH 45701, United States.
| | - Craig Goubeaux
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Mechanical Engineering, Ohio University, Athens, OH 45701, United States.
| | - John Cotton
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Mechanical Engineering, Ohio University, Athens, OH 45701, United States.
| | - Susan Williams
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Biomedical Sciences, Ohio University, Athens, OH 45701, United States.
| | - James Thomas
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Biomedical Sciences, Ohio University, Athens, OH 45701, United States; School of Rehabilitation and Communication Sciences, Ohio University, Athens, OH 45701, United States.
| | - Brian C Clark
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH 45701, United States; Department of Biomedical Sciences, Ohio University, Athens, OH 45701, United States; Department of Geriatric Medicine, Ohio University, Athens, OH 45701, United States.
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Zhao KD, Ben-Abraham EI, Magnuson DJ, Camp JJ, Berglund LJ, An KN, Bronfort G, Gay RE. Effect of Off-Axis Fluoroscopy Imaging on Two-Dimensional Kinematics in the Lumbar Spine: A Dynamic In Vitro Validation Study. J Biomech Eng 2016; 138:054502. [PMID: 26974192 DOI: 10.1115/1.4032995] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Indexed: 01/07/2023]
Abstract
Spine intersegmental motion parameters and the resultant regional patterns may be useful for biomechanical classification of low back pain (LBP) as well as assessing the appropriate intervention strategy. Because of its availability and reasonable cost, two-dimensional (2D) fluoroscopy has great potential as a diagnostic and evaluative tool. However, the technique of quantifying intervertebral motion in the lumbar spine must be validated, and the sensitivity assessed. The purpose of this investigation was to (1) compare synchronous fluoroscopic and optoelectronic measures of intervertebral rotations during dynamic flexion-extension movements in vitro and (2) assess the effect of C-arm rotation to simulate off-axis patient alignment on intervertebral kinematics measures. Six cadaveric lumbar-sacrum specimens were dissected, and active marker optoelectronic sensors were rigidly attached to the bodies of L2-S1. Fluoroscopic sequences and optoelectronic kinematic data (0.15-mm linear, 0.17-0.20 deg rotational, accuracy) were obtained simultaneously. After images were obtained in a true sagittal plane, the image receptor was rotated in 5 deg increments (posterior oblique angulations) from 5 deg to 15 deg. Quantitative motion analysis (qma) software was used to determine the intersegmental rotations from the fluoroscopic images. The mean absolute rotation differences between optoelectronic values and dynamic fluoroscopic values were less than 0.5 deg for all the motion segments at each off-axis fluoroscopic rotation and were not significantly different (P > 0.05) for any of the off-axis rotations of the fluoroscope. Small misalignments of the lumbar spine relative to the fluoroscope did not introduce measurement variation in relative segmental rotations greater than that observed when the spine and fluoroscope were perpendicular to each other, suggesting that fluoroscopic measures of relative segmental rotation during flexion-extension are likely robust, even when patient alignment is not perfect.
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Tissue loading created during spinal manipulation in comparison to loading created by passive spinal movements. Sci Rep 2016; 6:38107. [PMID: 27905508 PMCID: PMC5131487 DOI: 10.1038/srep38107] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 11/03/2016] [Indexed: 11/08/2022] Open
Abstract
Spinal manipulative therapy (SMT) creates health benefits for some while for others, no benefit or even adverse events. Understanding these differential responses is important to optimize patient care and safety. Toward this, characterizing how loads created by SMT relate to those created by typical motions is fundamental. Using robotic testing, it is now possible to make these comparisons to determine if SMT generates unique loading scenarios. In 12 porcine cadavers, SMT and passive motions were applied to the L3/L4 segment and the resulting kinematics tracked. The L3/L4 segment was removed, mounted in a parallel robot and kinematics of SMT and passive movements replayed robotically. The resulting forces experienced by L3/L4 were collected. Overall, SMT created both significantly greater and smaller loads compared to passive motions, with SMT generating greater anterioposterior peak force (the direction of force application) compared to all passive motions. In some comparisons, SMT did not create significantly different loads in the intact specimen, but did so in specific spinal tissues. Despite methodological differences between studies, SMT forces and loading rates fell below published injury values. Future studies are warranted to understand if loading scenarios unique to SMT confer its differential therapeutic effects.
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Mahallati S, Rouhani H, Preuss R, Masani K, Popovic MR. Multisegment Kinematics of the Spinal Column: Soft Tissue Artifacts Assessment. J Biomech Eng 2016; 138:2521876. [DOI: 10.1115/1.4033545] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Indexed: 11/08/2022]
Abstract
A major challenge in the assessment of intersegmental spinal column angles during trunk motion is the inherent error in recording the movement of bony anatomical landmarks caused by soft tissue artifacts (STAs). This study aims to perform an uncertainty analysis and estimate the typical errors induced by STA into the intersegmental angles of a multisegment spinal column model during trunk bending in different directions by modeling the relative displacement between skin-mounted markers and actual bony landmarks during trunk bending. First, we modeled the maximum displacement of markers relative to the bony landmarks with a multivariate Gaussian distribution. In order to estimate the distribution parameters, we measured these relative displacements on five subjects at maximum trunk bending posture. Then, in order to model the error depending on trunk bending angle, we assumed that the error grows linearly as a function of the bending angle. Second, we applied our error model to the trunk motion measurement of 11 subjects to estimate the corrected trajectories of the bony landmarks and investigate the errors induced into the intersegmental angles of a multisegment spinal column model. For this purpose, the trunk was modeled as a seven-segment rigid-body system described using 23 reflective markers placed on various bony landmarks of the spinal column. Eleven seated subjects performed trunk bending in five directions and the three-dimensional (3D) intersegmental angles during trunk bending were calculated before and after error correction. While STA minimally affected the intersegmental angles in the sagittal plane (<16%), it considerably corrupted the intersegmental angles in the coronal (error ranged from 59% to 551%) and transverse (up to 161%) planes. Therefore, we recommend using the proposed error suppression technique for STA-induced error compensation as a tool to achieve more accurate spinal column kinematics measurements. Particularly, for intersegmental rotations in the coronal and transverse planes that have small range and are highly sensitive to measurement errors, the proposed technique makes the measurement more appropriate for use in clinical decision-making processes.
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Affiliation(s)
- Sara Mahallati
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9, Canada; Rehabilitation Engineering Laboratory, Lyndhurst Centre, Toronto Rehabilitation Institute—University Health Network, 520 Sutherland Drive, Toronto, ON M4G 3V9, Canada e-mail:
| | - Hossein Rouhani
- Department of Mechanical Engineering, 10-368 Donadeo Innovation Centre for Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada
| | - Richard Preuss
- School of Physical and Occupational Therapy, McGill University, 3630 Promenade Sir-William-Osler, Montreal, QC H3G 1Y5, Canada; The Constance Lethbridge Rehabilitation Centre site of the Centre de Recherche Interdisciplinaire en Réadaptation (CRIR), 7005 Boulevard de Maisonneuve Ouest, Montreal, QC H4B 1T3, Canada
| | - Kei Masani
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9, Canada; Rehabilitation Engineering Laboratory, Lyndhurst Centre, Toronto Rehabilitation Institute—University Health Network, 520 Sutherland Drive, Toronto, ON M4G 3V9, Canada
| | - Milos R. Popovic
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, 164 College Street, Toronto, ON M5S 3G9, Canada; Rehabilitation Engineering Laboratory, Lyndhurst Centre, Toronto Rehabilitation Institute—University Health Network, 520 Sutherland Drive, Toronto, ON M4G 3V9, Canada
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Mahato NK, Montuelle S, Cotton J, Williams S, Thomas J, Clark B. Development of a morphology-based modeling technique for tracking solid-body displacements: examining the reliability of a potential MRI-only approach for joint kinematics assessment. BMC Med Imaging 2016; 16:38. [PMID: 27189195 PMCID: PMC4870733 DOI: 10.1186/s12880-016-0140-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 05/03/2016] [Indexed: 11/25/2022] Open
Abstract
Background Single or biplanar video radiography and Roentgen stereophotogrammetry (RSA) techniques used for the assessment of in-vivo joint kinematics involves application of ionizing radiation, which is a limitation for clinical research involving human subjects. To overcome this limitation, our long-term goal is to develop a magnetic resonance imaging (MRI)-only, three dimensional (3-D) modeling technique that permits dynamic imaging of joint motion in humans. Here, we present our initial findings, as well as reliability data, for an MRI-only protocol and modeling technique. Methods We developed a morphology-based motion-analysis technique that uses MRI of custom-built solid-body objects to animate and quantify experimental displacements between them. The technique involved four major steps. First, the imaging volume was calibrated using a custom-built grid. Second, 3-D models were segmented from axial scans of two custom-built solid-body cubes. Third, these cubes were positioned at pre-determined relative displacements (translation and rotation) in the magnetic resonance coil and scanned with a T1 and a fast contrast-enhanced pulse sequences. The digital imaging and communications in medicine (DICOM) images were then processed for animation. The fourth step involved importing these processed images into an animation software, where they were displayed as background scenes. In the same step, 3-D models of the cubes were imported into the animation software, where the user manipulated the models to match their outlines in the scene (rotoscoping) and registered the models into an anatomical joint system. Measurements of displacements obtained from two different rotoscoping sessions were tested for reliability using coefficient of variations (CV), intraclass correlation coefficients (ICC), Bland-Altman plots, and Limits of Agreement analyses. Results Between-session reliability was high for both the T1 and the contrast-enhanced sequences. Specifically, the average CVs for translation were 4.31 % and 5.26 % for the two pulse sequences, respectively, while the ICCs were 0.99 for both. For rotation measures, the CVs were 3.19 % and 2.44 % for the two pulse sequences with the ICCs being 0.98 and 0.97, respectively. A novel biplanar imaging approach also yielded high reliability with mean CVs of 2.66 % and 3.39 % for translation in the x- and z-planes, respectively, and ICCs of 0.97 in both planes. Conclusions This work provides basic proof-of-concept for a reliable marker-less non-ionizing-radiation-based quasi-dynamic motion quantification technique that can potentially be developed into a tool for real-time joint kinematics analysis.
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Affiliation(s)
- Niladri K Mahato
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, 45701, USA. .,Department of Biomedical Sciences, Ohio University, Athens, OH, 45701, USA.
| | - Stephane Montuelle
- Department of Biomedical Sciences, Ohio University, Athens, OH, 45701, USA
| | - John Cotton
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, 45701, USA.,Department of Mechanical Engineering, Ohio University, Athens, OH, 45701, USA
| | - Susan Williams
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, 45701, USA.,Department of Biomedical Sciences, Ohio University, Athens, OH, 45701, USA
| | - James Thomas
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, 45701, USA.,School of Rehabilitation and Communication Sciences, Ohio University, Athens, OH, 45701, USA
| | - Brian Clark
- Ohio Musculoskeletal and Neurological Institute, Ohio University, Athens, OH, 45701, USA.,Department of Biomedical Sciences, Ohio University, Athens, OH, 45701, USA.,Department of Geriatric Medicine, Ohio University, Athens, OH, 45701, USA
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Shen Y, Peng D, Dai Z, Zhong W. The effect of disc degeneration on anterior shear translation in the lumbar spine: Still more problems lie ahead. J Orthop Res 2016; 34:729. [PMID: 26519947 DOI: 10.1002/jor.23094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 10/26/2015] [Indexed: 02/04/2023]
Affiliation(s)
- Yi Shen
- Department of Orthopaedic Surgery, Second Xiangya Hospital and Central South University, Changsha, Hunan, P.R. China
| | - Dan Peng
- Department of Orthopaedic Surgery, Second Xiangya Hospital and Central South University, Changsha, Hunan, P.R. China
| | - Zhihui Dai
- Department of Orthopaedic Surgery, Second Xiangya Hospital and Central South University, Changsha, Hunan, P.R. China
| | - Weiye Zhong
- Department of Orthopaedic Surgery, Second Xiangya Hospital and Central South University, Changsha, Hunan, P.R. China
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Melnyk AD, Chak JD, Cripton PA, Oxland TR, Kelly A, Dvorak MF, Wen TL. Reply: The effect of disc degeneration on anterior shear translation in the lumbar spine. J Orthop Res 2016; 34:730-1. [PMID: 26519870 DOI: 10.1002/jor.23093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 10/29/2015] [Indexed: 02/04/2023]
Affiliation(s)
- Angela D Melnyk
- Department of Mechanical Engineering, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada.,International Collaboration on Repair Discoveries, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| | - Jason D Chak
- Department of Mechanical Engineering, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada.,International Collaboration on Repair Discoveries, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| | - Peter A Cripton
- Department of Mechanical Engineering, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada.,International Collaboration on Repair Discoveries, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| | - Thomas R Oxland
- Department of Mechanical Engineering, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada.,International Collaboration on Repair Discoveries, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| | - Adrienne Kelly
- Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada.,International Collaboration on Repair Discoveries, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
| | - Marcel F Dvorak
- Department of Orthopaedics, University of British Columbia, Vancouver, British Columbia, Canada.,International Collaboration on Repair Discoveries, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada
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Shen Y, Peng D, Dai Z, Zhong W. Reoperation rate and risk factors of elective spinal surgery for degenerative spondylolisthesis: still more challenges lie ahead. Spine J 2016; 16:270-1. [PMID: 26891923 DOI: 10.1016/j.spinee.2015.11.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 11/05/2015] [Indexed: 02/03/2023]
Affiliation(s)
- Yi Shen
- Department of Orthopaedic Surgery, Second Xiangya Hospital and Central South University, 139 Middle Renmin Rd, Changsha, Hunan 410011, China
| | - Dan Peng
- Department of Orthopaedic Surgery, Second Xiangya Hospital and Central South University, 139 Middle Renmin Rd, Changsha, Hunan 410011, China
| | - Zhihui Dai
- Department of Orthopaedic Surgery, Second Xiangya Hospital and Central South University, 139 Middle Renmin Rd, Changsha, Hunan 410011, China
| | - Weiye Zhong
- Department of Orthopaedic Surgery, Second Xiangya Hospital and Central South University, 139 Middle Renmin Rd, Changsha, Hunan 410011, China
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Lee JH, Lee SH. Clinical and Radiological Characteristics of Lumbosacral Lateral Disc Herniation in Comparison With Those of Medial Disc Herniation. Medicine (Baltimore) 2016; 95:e2733. [PMID: 26886615 PMCID: PMC4998615 DOI: 10.1097/md.0000000000002733] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Lateral disc herniation (foraminal and extra foraminal) has clinical characteristics that are different from those of medial disc herniation (central and subarticular), including older age, more frequent radicular pain, and neurologic deficits. This is supposedly because lateral disc herniation mechanically irritates or compresses the exiting nerve root or dorsal root ganglion inside of a narrow canal more directly than medial disc herniation. The purpose of this study was to investigate clinical and radiological characteristics of lateral disc herniation in comparison with medial disc herniation. The 352 subjects diagnosed with localized lumbosacral disc herniation and followed up for at least 12 months after completion of treatment were included and divided into medial and lateral disc herniation groups, according to the anatomical location of the herniated disc in axial plain of magnetic resonance image. Clinical and radiological data were obtained and compared between the two groups. The lateral group included 74 (21%) patients and the medial group included 278 (79%). Mean age of the lateral group was significantly higher than that in the medial group. The lateral group showed a significantly larger proportion of patients with radiating leg pain and multiple levels of disc herniations than the medial group. No significant differences were found in terms of gender, duration of pain, pretreatment numeric rating scale, severity of disc herniation (protrusion and extrusion), and presence of weakness in leg muscles. The proportion of patients who underwent surgery was not significantly different between the 2 groups. However, the proportion of patients who accomplished successful pain reduction after treatment was significantly smaller in the lateral than in the medial group. In conclusion, patients with lateral disc herniation were older and had larger proportion of radiating leg pain than those with medial disc herniation. Lateral disc herniation was more associated with multiple disc herniations and worse clinical outcomes after treatment than medial disc herniation.
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Affiliation(s)
- Jung Hwan Lee
- From the Department of Physical Medicine and Rehabilitation (JHL) and Department of Neurosurgery, Wooridul Spine Hospital, Seoul, Korea (SHL)
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Shen Y, Peng D, Dai Z, Zhong W. Letter to the Editor: Failure of single-level percutaneous endoscopic lumbar discectomy: a challenging clinical dilemma. J Neurosurg Spine 2016; 24:869-70. [PMID: 26824589 DOI: 10.3171/2015.9.spine151142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Yi Shen
- Second Xiangya Hospital and Central South University, Hunan, China
| | - Dan Peng
- Second Xiangya Hospital and Central South University, Hunan, China
| | - Zhihui Dai
- Second Xiangya Hospital and Central South University, Hunan, China
| | - Weiye Zhong
- Second Xiangya Hospital and Central South University, Hunan, China
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35
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Apportionment of lumbar L2–S1 rotation across individual motion segments during a dynamic lifting task. J Biomech 2015; 48:3709-15. [DOI: 10.1016/j.jbiomech.2015.08.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 08/12/2015] [Accepted: 08/18/2015] [Indexed: 11/17/2022]
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Bracht MA, Nunes GS, Celestino J, Schwertner DS, França LC, de Noronha M. Inter- and Intra-observer Agreement of the Motion Palpation Test for Lumbar Vertebral Rotational Asymmetry. Physiother Can 2015; 67:169-73. [PMID: 25931669 DOI: 10.3138/ptc.2014-16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
PURPOSE To investigate inter- and intra-observer agreement in the assessment of lumbar vertebral rotational (VR) asymmetry by a motion palpation test. METHODS For this prospective and descriptive test-retest study, 51 asymptomatic participants (40 women, 11 men; mean age 23.3 [SD 5.6] years) were recruited from the community. Each participant was assessed in two sessions by the same three observers, who assessed VR by means of a palpatory test for movement asymmetry. This test is performed by applying posteroanterior pressure in an alternating manner to the left and right transverse processes of a vertebra to determine motion asymmetry in the transverse plane and thus the vertebral position. Observers classified the vertebral position as neutral, rotation to the right, and rotation to the left; they were blinded to which participant was being assessed and to any previous results. RESULTS Intra- and inter-observer agreement was verified by the kappa coefficient (κ) and the weighted kappa coefficient (κ w ). Values of κ and κ w varied from 0.07 (95% CI, -0.10 to 0.245) to 0.37 (95% CI, 0.11-0.63) for intra-observer agreement and from 0.12 (95% CI, -0.06 to 0.29) to 0.30 (95% CI, 0.08-0.52) for inter-observer agreement. CONCLUSION The motion palpation test used to assess VR asymmetry has low agreement levels; therefore, its clinical significance for measuring vertebral position is questionable.
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Affiliation(s)
- Marcelo Anderson Bracht
- Department of Physiotherapy, Center of Health and Sport Sciences, Santa Catarina State University, Florianópolis, Brazil
| | - Guilherme S Nunes
- Department of Physiotherapy, Center of Health and Sport Sciences, Santa Catarina State University, Florianópolis, Brazil
| | - Jardel Celestino
- Department of Physiotherapy, Center of Health and Sport Sciences, Santa Catarina State University, Florianópolis, Brazil
| | - Debora Soccal Schwertner
- Department of Physiotherapy, Center of Health and Sport Sciences, Santa Catarina State University, Florianópolis, Brazil
| | - Leandro Cardoso França
- Department of Physiotherapy, Center of Health and Sport Sciences, Santa Catarina State University, Florianópolis, Brazil
| | - Marcos de Noronha
- Department of Physiotherapy, Center of Health and Sport Sciences, Santa Catarina State University, Florianópolis, Brazil ; Department of Allied Health, La Trobe University, Bendigo, VIC, Australia
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Abstract
Recent biomechanics studies have revealed distinct kinematic behavior of different lumbar segments. The mechanisms behind these segment-specific biomechanical features are unknown. This study investigated the in vivo geometric characteristics of human lumbar intervertebral discs. Magnetic resonance images of the lumbar spine of 41 young Chinese individuals were acquired. Disc geometry in the sagittal plane was measured for each subject, including the dimensions of the discs, nucleus pulposus (NP), and annulus fibrosus (AF). Segmental lordosis was also measured using the Cobb method.In general, the disc length increased from upper to lower lumbar levels, except that the L4/5 and L5/S1 discs had similar lengths. The L4/5 NP had a height of 8.6±1.3 mm, which was significantly higher than all other levels (P<0.05). The L5/S1 NP had a length of 21.6±3.1 mm, which was significantly longer than all other levels (P<0.05). At L4/5, the NP occupied 64.0% of the disc length, which was significantly less than the NP of the L5/S1 segment (72.4%) (P<0.05). The anterior AF occupied 20.5% of the L4/5 disc length, which was significantly greater than that of the posterior AF (15.6%) (P<0.05). At the L5/S1 segment, the anterior and posterior AFs were similar in length (14.1% and 13.6% of the disc, respectively). The height to length (H/L) ratio of the L4/5 NP was 0.45±0.06, which was significantly greater than all other segments (P<0.05). There was no correlation between the NP H/L ratio and lordosis. Although the lengths of the lower lumbar discs were similar, the geometry of the AF and NP showed segment-dependent properties. These data may provide insight into the understanding of segment-specific biomechanics in the lower lumbar spine. The data could also provide baseline knowledge for the development of segment-specific surgical treatments of lumbar diseases.
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Affiliation(s)
- Weiye Zhong
- From the Bioengineering Laboratory (WZ, SJD, MW, SW, ZL, TDC, KBW, GL), Department of Orthopedic Surgery, Harvard Medical School/Massachusetts General Hospital, Boston, MA; Department of Spinal Surgery (WZ), Second Xiangya Hospital and Central South University, Changsha, Hunan; and Department of Orthopedics (MW), China-Japan Union Hospital of Jilin University, Jilin, P.R. China
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Ellingson AM, Nuckley DJ. Altered helical axis patterns of the lumbar spine indicate increased instability with disc degeneration. J Biomech 2014; 48:361-9. [PMID: 25481221 DOI: 10.1016/j.jbiomech.2014.11.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 10/26/2014] [Accepted: 11/06/2014] [Indexed: 12/20/2022]
Abstract
Although the causes of low back pain are poorly defined and indistinct, degeneration of the intervertebral disc is most often implicated as the origin of pain. The biochemical and mechanical changes associated with degeneration result in the discs' inability to maintain structure and function, leading to spinal instability and ultimately pain. Traditionally, a clinical exam assessing functional range-of-motion coupled with T2-weighted MRI revealing disc morphology are used to evaluate spinal health; however, these subjective measures fail to correlate well with pain or provide useful patient stratification. Therefore, improved quantification of spinal motion and objective MRI measures of disc health are necessary. An instantaneous helical axis (IHA) approach provides rich temporal three-dimensional data describing the pathway of motion, which is easily visualized. Eighteen cadaveric osteoligamentous lumbar spines (L4-5) from throughout the degenerative spectrum were tested in a pure moment fashion. IHA were calculated for flexion-extension and lateral bending. A correlational study design was used to determine the relationship between disc measurements from quantitative T2* MRI and IHA metrics. Increased instability and out-of-plane rotation with diminished disc health was observed during lateral bending, but not flexion-extension. This new analysis strategy examines the entire pathway of motion, rather than simplifying spinal kinematics to its terminal ends of motion and provides a more sensitive kinematic measurement of disc health. Ultimately, through the use of 3D dynamic fluoroscopy or similar methods, a patient's functional IHA in lateral bending may be measured and used to assess their disc health for diagnosis, progression tracking, and treatment evaluation.
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Affiliation(s)
| | - David J Nuckley
- Department of Physical Medicine and Rehabilitation, University of Minnesota. Orthopedic Biomechanics Laboratory, University of Minnesota, Minneapolis, MN, USA
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Oswestry Disability Index is a better indicator of lumbar motion than the Visual Analogue Scale. Spine J 2014; 14:1860-5. [PMID: 24216395 DOI: 10.1016/j.spinee.2013.10.027] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 08/01/2013] [Accepted: 10/23/2013] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Lumbar pathology is often associated with axial pain or neurologic complaints. It is often presumed that such pain is associated with decreased lumbar motion; however, this correlation is not well established. The utility of various outcome measures that are used in both research and clinical practice have been studied, but the connection with range of motion (ROM) has not been well documented. PURPOSE The current study was performed to assess objectively the postulated correlation of lumbar complaints (based on standardized outcome measures) with extremes of lumbar ROM and functional ROM (fROM) with activities of daily living (ADLs) as assessed with an electrogoniometer. STUDY DESIGN/SETTING This study was a clinical cohort study. PATIENT SAMPLE Subjects slated to undergo a lumbar intervention (injection, decompression, and/or fusion) were enrolled voluntarily in the study. OUTCOME MEASURES The two outcome measures used in the study were the Visual Analogue Scale (VAS) for axial extremity, lower extremity, and combined axial and lower extremity, as well as the Oswestry Disability Index (ODI). METHODS Pain and disability scores were assessed with the VAS score and ODI. A previously validated electrogoniometer was used to measure ROM (extremes of motion in three planes) and fROM (functional motion during 15 simulated activities of daily living). Pain and disability scores were analyzed for statistically significant association with the motion assessments using linear regression analyses. RESULTS Twenty-eight men and 39 women were enrolled, with an average age of 55.6 years (range, 18-79 years). The ODI and VAS were associated positively (p<.001). Combined axial and lower extremity VAS scores were associated with lateral and rotational ROM (p<.05), but not with flexion/extension or any fROM. Similar findings were noted for separately analyzed axial and lower extremity VAS scores. On the other hand, the ODI correlated inversely with ROM in all planes, and fROM in at least one plane for 10 of 15 ADLs (p<.05). CONCLUSIONS Extremes of lumbar motion and motions associated with ADLs are of increasing clinical interest. Although the ODI and VAS are associated with each other, the ODI appears to be a better predictor of these motion parameters than the VAS (axial extremity, lower extremity, or combined) and may be more useful in the clinical setting when considering functional movement parameters.
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The basis of mechanical instability in degenerative disc disease: a cadaveric study of abnormal motion versus load distribution. Spine (Phila Pa 1976) 2014; 39:1032-43. [PMID: 24583744 DOI: 10.1097/brs.0000000000000292] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN A biomechanical study in cadaveric lumbar spine. OBJECTIVE To establish the basis of mechanical stability in degenerative disc disease from the relationship between range of motion (ROM), neutral zone motion (NZ), intradiscal pressure profile, and instantaneous axis or rotation (IAR) in advancing grades of disc degeneration. SUMMARY OF BACKGROUND DATA The basis of mechanical instability in lumbar disc degeneration remains poorly understood. Controversy exists between abnormal motion and abnormal loading theories. METHODS Thirty-nine lumbar motion segments were graded for staging of disc degeneration with magnetic resonance scan. These specimens were tested for ROM and NZ in a 6 df spine simulator, with 7.5 N·m unconstrained, cyclical loading. Continuous tracking of IAR was derived from ROM data. Intradiscal pressure profiles were determined using needle-mounted pressure transducer, drawn across the disc space under constant loading. RESULTS The ROM showed insignificant change, but a trend of increase from grade I through III and a decrease with advanced degeneration. NZ increased significantly with advancing disc degeneration. Intradiscal pressure profile showed an even distribution of the load in normal discs but a depressurized nucleus and irregular spikes of excessive loading, with advancing degeneration. The IAR showed a smooth excursion in normal versus irregular jerky excursion in degenerated discs, without significant change in excursion. The center of rotation, derived from IAR, showed significantly increased vertical translation with advancing degeneration, indicating an abnormal quality of motion. CONCLUSION The study established a basis of mechanical instability in the lumbar spine with advancing disc degeneration as an abnormal quality of motion represented by variation in IAR and center of rotation, increased NZ motion without any increase in quantity of motion, and abnormal load distribution across the disc space with spikes of high load amidst depressurized nucleus. The study cannot identify clinical instability but finds an association between the abnormal motions and the abnormal load distribution in mechanical instability. LEVEL OF EVIDENCE N/A.
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Wu M, Wang S, Driscoll SJ, Cha TD, Wood KB, Li G. Dynamic motion characteristics of the lower lumbar spine: implication to lumbar pathology and surgical treatment. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2014; 23:2350-8. [PMID: 24777671 DOI: 10.1007/s00586-014-3316-9] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 04/11/2014] [Accepted: 04/13/2014] [Indexed: 11/30/2022]
Abstract
PURPOSE Many studies have reported on the segmental motion range of the lumbar spine using various in vitro and in vivo experimental designs. However, the in vivo weightbearing dynamic motion characteristics of the L4-5 and L5-S1 motion segments are still not clearly described in literature. This study investigated in vivo motion of the lumbar spine during a weight-lifting activity. METHODS Ten asymptomatic subjects (M/F: 5/5; age: 40-60 years) were recruited. The lumbar segment of each subject was MRI-scanned to construct 3D models of the L2-S1 vertebrae. The lumbar spine was then imaged using a dual fluoroscopic imaging system as the subject performed a weight-lifting activity from a lumbar flexion position (45°) to maximal extension position. The 3D vertebral models and the fluoroscopic images were used to reproduce the in vivo vertebral positions along the motion path. The relative translations and rotations of each motion segment were analyzed. RESULTS All vertebral motion segments, L2-3, L3-4, L4-5 and L5-S1, rotated similarly during the lifting motion. L4-5 showed the largest anterior-posterior (AP) translation with 2.9 ± 1.5 mm and was significantly larger than L5-S1 (p < 0.05). L5-S1 showed the largest proximal-distal (PD) translation with 2.8 ± 0.9 mm and was significantly larger than all other motion segments (p < 0.05). CONCLUSIONS The lower lumbar motion segments L4-5 and L5-S1 showed larger AP and PD translations, respectively, than the higher vertebral motion segments during the weight-lifting motion. The data provide insight into the physiological motion characteristics of the lumbar spine and potential mechanical mechanisms of lumbar disease development.
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Affiliation(s)
- Minfei Wu
- Bioengineering Laboratory, Department of Orthopaedic Surgery, Harvard Medical School/Massachusetts General Hospital, Boston, MA, USA
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MacWilliams BA, Rozumalski A, Swanson AN, Wervey RA, Dykes DC, Novacheck TF, Schwartz MH. Assessment of three-dimensional lumbar spine vertebral motion during gait with use of indwelling bone pins. J Bone Joint Surg Am 2013; 95:e1841-8. [PMID: 24306707 DOI: 10.2106/jbjs.l.01469] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND This study quantifies the three-dimensional motion of lumbar vertebrae during gait via direct in vivo measurement with the use of indwelling bone pins with retroreflective markers and motion capture. Two previous studies in which bone pins were used were limited to instrumentation of two vertebrae, and neither evaluated motions during gait. While several imaging-based studies of spinal motion have been reported, the restrictions in measurement volume that are inherent to imaging modalities are not conducive to gait applications. METHODS Eight healthy volunteers with a mean age of 25.1 years were screened to rule out pathology. Then, after local anesthesia was administered, two 1.6-mm Kirschner wires were inserted into the L1, L2, L3, L4, L5, and S1 spinous processes. The wires were clamped together, and reflective marker triads were attached to the end of each wire couple. Subjects underwent spinal computed tomography to anatomically register each vertebra to the attached triad. Subjects then walked several times in a calibrated measurement field at a self-selected speed while motion data were collected. RESULTS Less than 4° of lumbar intersegmental motion was found in all planes. Motions were highly consistent between subjects, resulting in small group standard deviations. The largest motions were in the coronal plane, and the middle lumbar segments exhibited greater motions than the segments cephalad and caudad to them. Intersegmental lumbar flexion and axial rotation motions were both extremely small at all levels. CONCLUSIONS The lumbar spine chiefly acts to contribute abduction during stance and adduction during swing to balance the relative motions between the trunk and pelvis. The lumbar spine acts in concert with the thoracic spine. While the lumbar spine chiefly contributes coronal plane motion, the thoracic spine contributes the majority of the transverse plane motion. Both contribute flexion motion in an offset phase pattern. CLINICAL RELEVANCE This is a valid model for measuring the three-dimensional motion of the spine. Normative data were obtained to better understand the effects of spine disorders on vertebral motion over the gait cycle.
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Affiliation(s)
- Bruce A MacWilliams
- Motion Analysis Laboratory, Shriners Hospitals for Children-Salt Lake City, Fairfax Road at Virginia Street, Salt Lake City, UT 84103. E-mail address:
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Motion characteristics of the lumbar spinous processes with degenerative disc disease and degenerative spondylolisthesis. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2013; 22:2702-9. [PMID: 23903997 DOI: 10.1007/s00586-013-2918-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 06/23/2013] [Accepted: 07/14/2013] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Recently, interspinous process devices have attracted much attention since they can be implanted between the lumbar spinous processes (LSP) of patients with degenerative disc disease (DDD) and degenerative spondylolisthesis (DLS) using a minimally invasive manner. However, the motion characters of the LSP in the DLS and DDD patients have not been reported. This study is aimed at investigating the kinematics of the lumbar spinous processes in patients with DLS and DDD. METHODS Ten patients with DDD at L4-S1 and ten patients with DLS at L4-L5 were studied. The positions of the vertebrae (L2-L5) at supine, standing, 45° trunk flexion, and maximal extension positions were determined using MRI-based models and dual fluoroscopic images. The shortest ISP distances were measured and compared with those of healthy subjects that have been previously reported. RESULTS The shortest distance of the interspinous processes (ISP) gradually decreased from healthy subjects to DDD and to DLS patients when measured in the supine, standing, and extension positions. During supine-standing and flexion-extension activities, the changes in the shortest ISP distances in DDD patients were 2 ± 1.2 and 4.8 ± 2.1 mm at L4-L5; in DLS patients they were 0.5 ± 0.4 and 2.8 ± 1.7 mm at L4-L5, respectively. The range of motion is increased in DDD patients but decreased in DLS patients when compared with those of the healthy subjects. No significantly different changes were detected at L2-L3 and L3-L4 levels. CONCLUSION At the involved level, the hypermobility of the LSP was seen in DDD and hypomobility of the LSP in DLS patients. The data may be instrumental for improving ISP surgeries that are aimed at reducing post-operative complications such as bony fracture and device dislocations.
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Fazey PJ, Song S, Price RI, Singer KP. Nucleus pulposus deformation in response to rotation at L1-2 and L4-5. Clin Biomech (Bristol, Avon) 2013; 28:586-9. [PMID: 23608479 DOI: 10.1016/j.clinbiomech.2013.03.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2012] [Revised: 03/25/2013] [Accepted: 03/26/2013] [Indexed: 02/07/2023]
Abstract
BACKGROUND Spinal rotation couples with lateral flexion as a composite movement. Few data report the in vivo mechanical deformation of the nucleus pulposus following sustained rotation. MRI provides a non-invasive method of examining nucleus pulposus deformation by mapping the hydration signal distribution within the intervertebral disc. METHODS T1 weighted coronal and sagittal lumbar images and T2 weighted axial images at L1-2 and L4-5 were obtained from 10 asymptomatic subjects (mean age 29, range: 24-34 years) in sustained flexed and extended positions plus combined positions of left rotation with flexion and extension. Nucleus pulposus deformation was tracked by mapping the change in hydration profiles from coronal and sagittal pixel measurements. FINDINGS An average sagittal change in position of 44° (SD 14.5°) from flexion to extension was recorded between L1 and S1 (range: 18°- 60°) resulting in a mean anterior nucleus pulposus deformation of 16% of disc hydration profile (range: 3.5%-19%) in 19/20 discs. When rotation was combined with either flexion or extension, mean coronal deformation was 4.8% (SD-5.1%; range: 0.4%-15%). Lateral nucleus pulposus deformation direction varied in rotation (44% deformed left and 56% deformed right). Intersegmental lateral flexion direction more strongly predicted nucleus pulposus deformation direction with 75% deforming contralaterally. INTERPRETATION Nucleus pulposus deformation direction in young subjects was more predictable following sagittal position change than in rotation combined with flexion or extension. Deformation magnitude was reduced in rotated positions. Intersegmental lateral flexion was a stronger predictor of nucleus pulposus deformation direction.
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Affiliation(s)
- Peter J Fazey
- The Centre for Musculoskeletal Studies, School of Surgery, The University of Western Australia, Australia.
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Miao J, Wang S, Park WM, Xia Q, Fang X, Wood K, Li G. Segmental spinal canal volume in patients with degenerative spondylolisthesis. Spine J 2013; 13:706-12. [PMID: 23541448 PMCID: PMC3679236 DOI: 10.1016/j.spinee.2013.02.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Revised: 11/08/2012] [Accepted: 02/08/2013] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Lumbar degenerative spondylolisthesis (DS), typically characterized by the forward slippage of the superior vertebra of a lumbar motion segment, is a common spinal pathological condition in elderly individuals. Significant deformation and volume changes of the spinal canal can occur because of the vertebral slippage, but few data have been reported on these anatomic variations in DS patients. Whether to restore normal anatomy, such as reduction of the slippage and restoration of disc height, is still not clear in surgery. PURPOSE This study was designed to determine the volume change of the spinal canal and detect specific anatomic factors affecting the spinal canal volume in DS patients. STUDY DESIGN/SETTING A case-control study. METHODS Nine asymptomatic volunteers (mean age 54.4) and 9 patients with L4/L5 DS (mean age 73.4) were recruited. All patients had intermittent claudication and different extent low back pain, and two patients also had leg pain. L4/L5 vertebral motion segment unit of each subject was reconstructed using three-dimensional computed tomography or magnetic resonance images in a solid modeling software. In vivo lumbar vertebral motion during functional postures (supine, standing upright, flexion, and extension) was determined using a dual fluoroscopic imaging technique. The volume of the spinal canal was measured at each functional posture. Various anatomic parameters (disc height, cross-sectional area of the canal, left-right diameter of the canal, anterior-posterior diameter of the canal, slippage, posture, intervertebral disc angle [DA], etc.) that may potentially affect the canal volume were also measured, and their correlations with the volume change of spinal canal were analyzed. This study was funded by a 2-year, $275,000 grant from the National Institutes of Health. RESULTS On average, spinal canal volume was larger at supine and flexion postures than at stand and extension postures in both the DS and the asymptomatic groups. Spinal canal volume of the DS patients were significantly lower than that of the asymptomatic subjects under all the four postures (p<.05). Correlation analysis showed that spinal canal volume was strongly affected by the posterior disc height (Pearson correlation coefficient γb=0.822) and the slippage percentage (γb=-0.593) and moderately affected by the anterior disc height (γb=0.300) and the DA (γb=-0.237). CONCLUSIONS The volume of spinal canal is affected by multiple factors. Increased spinal canal volume at supine and flexion positions may explain the clinical observations of relief of symptoms at these postures in DS patients. The data also suggest that reduction of slipped vertebral body, decrease of DA, intervertebral distraction, and decompression could all be effective to increase the canal volume of DS patients thus to relieve clinical symptoms.
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Affiliation(s)
- Jun Miao
- Bioengineering Lab, Department of Orthopaedic Surgery, Massachussets General Hospital/Harvard Medical School, Boston, MA
- Spinal Surgery Department, Tianjin Hospital, Tianjin, China
| | - Shaobai Wang
- Bioengineering Lab, Department of Orthopaedic Surgery, Massachussets General Hospital/Harvard Medical School, Boston, MA
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA
| | - Won Man Park
- Bioengineering Lab, Department of Orthopaedic Surgery, Massachussets General Hospital/Harvard Medical School, Boston, MA
- Department of Mechanical Engineering, Kyung Hee University, Yongin, Korea
| | - Qun Xia
- Spinal Surgery Department, Tianjin Hospital, Tianjin, China
| | - Xiutong Fang
- Bioengineering Lab, Department of Orthopaedic Surgery, Massachussets General Hospital/Harvard Medical School, Boston, MA
- Department of Orthopedics, Beijing Shijitan Hospital, Beijing Capital Medical University, Beijing, China
| | - Kirkham Wood
- Bioengineering Lab, Department of Orthopaedic Surgery, Massachussets General Hospital/Harvard Medical School, Boston, MA
| | - Guoan Li
- Bioengineering Lab, Department of Orthopaedic Surgery, Massachussets General Hospital/Harvard Medical School, Boston, MA
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Iatridis JC, Nicoll SB, Michalek AJ, Walter BA, Gupta MS. Role of biomechanics in intervertebral disc degeneration and regenerative therapies: what needs repairing in the disc and what are promising biomaterials for its repair? Spine J 2013; 13:243-62. [PMID: 23369494 PMCID: PMC3612376 DOI: 10.1016/j.spinee.2012.12.002] [Citation(s) in RCA: 219] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 07/26/2012] [Accepted: 12/09/2012] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Degeneration and injuries of the intervertebral disc (IVD) result in large alterations in biomechanical behaviors. Repair strategies using biomaterials can be optimized based on the biomechanical and biological requirements of the IVD. PURPOSE To review the present literature on the effects of degeneration, simulated degeneration, and injury on biomechanics of the IVD, with special attention paid to needle puncture injuries, which are a pathway for diagnostics and regenerative therapies and the promising biomaterials for disc repair with a focus on how those biomaterials may promote biomechanical repair. STUDY DESIGN A narrative review to evaluate the role of biomechanics on disc degeneration and regenerative therapies with a focus on what biomechanical properties need to be repaired and how to evaluate and accomplish such repairs using biomaterials. Model systems for the screening of such repair strategies are also briefly described. METHODS Articles were selected from two main PubMed searches using keywords: intervertebral AND biomechanics (1,823 articles) and intervertebral AND biomaterials (361 articles). Additional keywords (injury, needle puncture, nucleus pressurization, biomaterials, hydrogel, sealant, tissue engineering) were used to narrow the articles down to the topics most relevant to this review. RESULTS Degeneration and acute disc injuries have the capacity to influence nucleus pulposus (NP) pressurization and annulus fibrosus (AF) integrity, which are necessary for an effective disc function and, therefore, require repair. Needle injection injuries are of particular clinical relevance with the potential to influence disc biomechanics, cellularity, and metabolism, yet these effects are localized or small and more research is required to evaluate and reduce the potential clinical morbidity using such techniques. NP replacement strategies, such as hydrogels, are required to restore the NP pressurization or the lost volume. AF repair strategies including cross-linked hydrogels, fibrous composites, and sealants offer promise for regenerative therapies to restore AF integrity. Tissue engineered IVD structures, as a single implantable construct, may promote greater tissue integration due to the improved repair capacity of the vertebral bone. CONCLUSIONS IVD height, neutral zone characteristics, and torsional biomechanics are sensitive to specific alterations in the NP pressurization and AF integrity and must be addressed for an effective functional repair. Synthetic and natural biomaterials offer promise for NP replacement, AF repair, as an AF sealant, or whole disc replacement. Meeting mechanical and biological compatibilities are necessary for the efficacy and longevity of the repair.
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Affiliation(s)
- James C. Iatridis
- Leni and Peter W. May Department of Orthopaedics, Mount Sinai School of Medicine, New York, NY
| | - Steven B. Nicoll
- Department of Biomedical Engineering, The City College of New York, New York, NY
| | - Arthur J. Michalek
- Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, VT
| | - Benjamin A. Walter
- Leni and Peter W. May Department of Orthopaedics, Mount Sinai School of Medicine, New York, NY,Department of Biomedical Engineering, The City College of New York, New York, NY
| | - Michelle S. Gupta
- Department of Biomedical Engineering, The City College of New York, New York, NY
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Wang S, Park WM, Gadikota HR, Miao J, Kim YH, Wood KB, Li G. A combined numerical and experimental technique for estimation of the forces and moments in the lumbar intervertebral disc. Comput Methods Biomech Biomed Engin 2012; 16:1278-86. [PMID: 22551235 DOI: 10.1080/10255842.2012.668537] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Evaluation of the loads on lumbar intervertebral discs (IVD) is critically important since it is closely related to spine biomechanics, pathology and prosthesis design. Non-invasive estimation of the loads in the discs remains a challenge. In this study, we proposed a new technique to estimate in vivo loads in the IVD using a subject-specific finite element (FE) model of the disc and the kinematics of the disc endplates as input boundary conditions. The technique was validated by comparing the forces and moments in the discs calculated from the FE analyses to the in vitro experiment measurements of three corresponding lumbar discs. The results showed that the forces and moments could be estimated within an average error of 20%. Therefore, this technique can be a promising tool for non-invasive estimation of the loads in the discs and may be extended to be used on living subjects.
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Affiliation(s)
- Shaobai Wang
- a Bioengineering Laboratory, Department of Orthopaedic Surgery , Massachusetts General Hospital/Harvard Medical School , 55 Fruit St., GRJ 1215, Boston , MA 02114 , USA
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