1
|
Bisson DG, Sheng K, Kocabas S, Ocay DD, Ferland CE, Saran N, Ouellet JA, Haglund L. Axial rotation and pain are associated with facet joint osteoarthritis in Adolescent Idiopathic Scoliosis. Osteoarthritis Cartilage 2023:S1063-4584(23)00729-X. [PMID: 36948383 DOI: 10.1016/j.joca.2023.03.007] [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: 10/06/2022] [Revised: 03/06/2023] [Accepted: 03/12/2023] [Indexed: 03/24/2023]
Abstract
OBJECTIVE Facet joints are crucial for spinal stability and develop premature osteoarthritis in patients with adolescent idiopathic scoliosis (AIS). Here, we evaluated the association between facet joint cartilage and subchondral bone homeostasis, perceived back pain and 3-dimensional spinal deformity to understand better the role of facet joint degeneration in AIS progression and pain. METHOD Cartilage and bone osteoarthritic states of AIS facet joint surgical samples were characterized using histological OARSI scoring, visual morphological grading and μCT analysis, respectively. Back pain was self-reported using a numerical rating scale and expressed relative to the location on the patient's back. The scoliotic curves from our patient cohort were digitally reconstructed using biplanar radiographs and the eOS system (EOS imaging). The deformity was then reduced to 3 intervertebral angles (coronal, sagittal and axial) for each pair of bilateral facet joints. Statistical associations between the intervertebral angles, osteoarthritis parameters and pain intensity were performed using the Spearman method and Friedman test. RESULTS Facet joint cartilage degeneration was associated with decreased subchondral bone volume and quality. Most importantly, asymmetrical, and overall degeneration of facet joints was strongly correlated to intervertebral axial rotation. Additionally, kyphotic intervertebral segments in the sagittal plane were good predictors of increased facet joint degeneration and back pain. CONCLUSION Facet joint degeneration is associated with axial deformity, kyphotic intervertebral angle and back pain intensity in AIS. These results suggest that facet joints are important features to consider for rotational instability in AIS spines and related disease progression and perceived back pain.
Collapse
Affiliation(s)
- Daniel G Bisson
- Orthopaedic Research Laboratory, Shriners Hospital for Children, Montreal, Canada; Department of Experimental Surgery, McGill University, Montreal, Canada
| | - Kai Sheng
- Orthopaedic Research Laboratory, Shriners Hospital for Children, Montreal, Canada; Department of Experimental Surgery, McGill University, Montreal, Canada
| | - Semsi Kocabas
- Orthopaedic Research Laboratory, Shriners Hospital for Children, Montreal, Canada; Department of Experimental Surgery, McGill University, Montreal, Canada
| | - Don Daniel Ocay
- Department of Experimental Surgery, McGill University, Montreal, Canada
| | - Catherine E Ferland
- Department of Clinical Research, Shriner's Hospital for Children, Montreal, Canada; Department of Anesthesia, McGill University, Montreal, Canada
| | - Neil Saran
- Orthopaedic Research Laboratory, Shriners Hospital for Children, Montreal, Canada; Department of Experimental Surgery, McGill University, Montreal, Canada
| | - Jean A Ouellet
- Orthopaedic Research Laboratory, Shriners Hospital for Children, Montreal, Canada; Department of Experimental Surgery, McGill University, Montreal, Canada
| | - Lisbet Haglund
- Orthopaedic Research Laboratory, Shriners Hospital for Children, Montreal, Canada; Department of Experimental Surgery, McGill University, Montreal, Canada.
| |
Collapse
|
2
|
Davis CM, Grant CA, Izatt MT, Askin GN, Labrom RD, Adam CJ, Pearcy MJ, Little JP. Characterization of progressive changes in pedicle morphometry and neurovascular anatomy during growth in adolescent idiopathic scoliosis versus adolescents without scoliosis. Spine Deform 2020; 8:1193-1204. [PMID: 32557264 DOI: 10.1007/s43390-020-00160-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 06/08/2020] [Indexed: 11/30/2022]
Abstract
STUDY DESIGN Prospective cohort study. OBJECTIVES Investigate the progressive changes in pedicle morphometry and the spatial relationship between the pedicles and neurovascular structures in patients with AIS during growth. Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional spine deformity. AIS pedicles are known to be asymmetrical when compared to adolescents without scoliosis. Defining the anatomical changes occurring progressively in scoliosis as it increases with time and growth is essential for understanding the pathophysiology of scoliosis and for treatment planning. MRI is the ideal method to study the growing spine without ionising radiation. METHODS 24 females with AIS (mean 12.6 years, right sided main thoracic curves) and 20 non-scoliotic females (mean 11.5 years) were selected from an ongoing database. Participants underwent two 3D MRI scans (3 T scanner, T1, 0.5 mm isotropic voxels) approximately 1 year apart (AIS: mean 1.3 ± 0.05 years, control: mean 1.0 ± 0.1 years). The pedicle width, chord length, pedicle height, transverse pedicle angle, sagittal pedicle angle, distance from vertebrae to aorta and distance from pedicle to dural sac were measured from T5 to T12. Inter- and intra-observer variability was assessed. RESULTS From scans 1-2 in the AIS group, the dural sac became closer to the left pedicle (p < 0.05, T6, T8-T10 and T12) while the distance from the vertebrae to the aorta increased (p < 0.05, T6-T10). No significant changes in these measurements were observed in the non-scoliotic group. Between scans, the AIS chord length and transverse pedicle angle increased on the left side around the apex (p < 0.05) creating asymmetries not seen in the non-scoliotic cohort. The mean pedicle height increased symmetrically in the non-scoliosis cohort (p < 0.05) and asymmetrically in the AIS group with the right side growing faster than the left at T6-T7 (p < 0.05). CONCLUSION Asymmetrical growth patterns occur in the vertebral posterior elements of AIS patients compared to the symmetrical growth patterns found in the non-scoliotic participants. LEVEL OF EVIDENCE Level II prospective comparative study.
Collapse
Affiliation(s)
- Colin M Davis
- Biomechanics and Spine Research Group, Institute of Health and Biomedical Innovation at Centre for Children's Health Research, Queensland University of Technology and Mater Health Services, Level 5, 62 Graham Street, South Brisbane, QLD, 4101, Australia.,Queensland Children's Hospital, Brisbane, Australia
| | - Caroline A Grant
- Biomechanics and Spine Research Group, Institute of Health and Biomedical Innovation at Centre for Children's Health Research, Queensland University of Technology and Mater Health Services, Level 5, 62 Graham Street, South Brisbane, QLD, 4101, Australia
| | - Maree T Izatt
- Biomechanics and Spine Research Group, Institute of Health and Biomedical Innovation at Centre for Children's Health Research, Queensland University of Technology and Mater Health Services, Level 5, 62 Graham Street, South Brisbane, QLD, 4101, Australia
| | - Geoffrey N Askin
- Biomechanics and Spine Research Group, Institute of Health and Biomedical Innovation at Centre for Children's Health Research, Queensland University of Technology and Mater Health Services, Level 5, 62 Graham Street, South Brisbane, QLD, 4101, Australia.,Queensland Children's Hospital, Brisbane, Australia
| | - Robert D Labrom
- Biomechanics and Spine Research Group, Institute of Health and Biomedical Innovation at Centre for Children's Health Research, Queensland University of Technology and Mater Health Services, Level 5, 62 Graham Street, South Brisbane, QLD, 4101, Australia.,Queensland Children's Hospital, Brisbane, Australia
| | - Clayton J Adam
- Biomechanics and Spine Research Group, Institute of Health and Biomedical Innovation at Centre for Children's Health Research, Queensland University of Technology and Mater Health Services, Level 5, 62 Graham Street, South Brisbane, QLD, 4101, Australia
| | - Mark J Pearcy
- Biomechanics and Spine Research Group, Institute of Health and Biomedical Innovation at Centre for Children's Health Research, Queensland University of Technology and Mater Health Services, Level 5, 62 Graham Street, South Brisbane, QLD, 4101, Australia
| | - J Paige Little
- Biomechanics and Spine Research Group, Institute of Health and Biomedical Innovation at Centre for Children's Health Research, Queensland University of Technology and Mater Health Services, Level 5, 62 Graham Street, South Brisbane, QLD, 4101, Australia.
| |
Collapse
|
3
|
Zhang L, Wang H. Computed tomographic morphometric analysis of lateral inclination C1 pedicle screw for atlantoaxial instability patients with a narrow C1 posterior arch. Kaohsiung J Med Sci 2018; 34:700-704. [DOI: 10.1016/j.kjms.2018.08.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 05/06/2018] [Accepted: 08/07/2018] [Indexed: 11/16/2022] Open
|
4
|
Huang J, Zhang P, Jian X, Jiang H. The Prevalence and Distribution of Vertebral Pedicles in Adolescent Idiopathic Scoliosis in Chinese people: A Computed Tomography-Based Study of 2958 Vertebral Pedicles. World Neurosurg 2018; 119:e560-e567. [PMID: 30077019 DOI: 10.1016/j.wneu.2018.07.211] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 07/23/2018] [Accepted: 07/24/2018] [Indexed: 10/28/2022]
Abstract
OBJECTIVE To explore the prevalence and distribution of abnormal vertebral pedicles in adolescent idiopathic scoliosis (AIS) in Chinese people. METHODS We retrospectively reviewed AIS patients at a single institution between 2011 and 2017. Transverse pedicle widths from T1 to L5 were measured carefully using computed tomography, including cancellous and cortical channels. Pedicle morphology was classified as: type A, a cancellous channel larger than 4 mm; type B, a cancellous channel measuring 2-4 mm; type C, a cancellous channel smaller than 2 mm with an entirely cortical channel of 2 mm or greater; or type D, a cortical channel smaller than 2 mm. Types B, C, and D were defined as abnormal. Prevalence and distribution of abnormal pedicles were assessed. RESULTS Eighty-seven patients with AIS, with a total of 2958 vertebral pedicles, were carefully measured and classified. The total prevalence of abnormal vertebral pedicles was as high as 65%, with type B comprising 40%, type C comprising 23%, and type D comprising 2%. Pedicles were located between T2 and T10 in 84% of type C and 91% of type D cases. Female sex, proximal thoracic location, major curve greater than 70 degrees, and concave pedicle may be risk factors for type C and D pedicles. CONCLUSIONS There is a significantly high prevalence of abnormal pedicles in AIS in Chinese people, with a total prevalence of 65%. Female sex, proximal thoracic location, major curve greater than 70 degrees, and concave pedicle may be risk factors for type C and D pedicles.
Collapse
Affiliation(s)
- Jie Huang
- Department of Orthopedics, the Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Peng Zhang
- Second Department of Surgery, Jinyintan Hospital of Wuhan, Wuhan, China
| | - Xiaofei Jian
- Department of Orthopedics, the Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Honghui Jiang
- Department of Orthopedics, the Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| |
Collapse
|
5
|
Morphometric Analysis of Vertebral Growth Using Magnetic Resonance Imaging in the Normal Skeletally Immature Spine. Spine (Phila Pa 1976) 2018; 43:133-140. [PMID: 20508552 DOI: 10.1097/brs.0b013e3181c80ec5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Morphometic analysis of the thoracic and lumbar pedicle, vertebral body, and spinal canal in the normal infantile and juvenile patients using magnetic resonance imaging (MRI). OBJECTIVE To 3-dimensionally characterize the growth of the vertebral column in vivo and define the accurate dynamic growth rate of the normal immature spine. SUMMARY OF BACKGROUND DATA There is a relationship between growth of the spine and the development of spinal deformity. Currently available information regarding vertebral column growth is remarkably limited and poorly defined. The detailed morphologic research is needed to obtain accurate data with regard to growth of the vertebra, including coronal, sagittal, and axial growth information for normal states. METHODS A total of 34 pediatric patients with a normal straight spine who had MRI from thoracic vertebra 1 to lumbar vertebra 5 were assigned to 3 groups: infantile group (n = 11), 0 to 3 years of age; juvenile-young group (n = 16), 4 to 7 years of age; and juvenile-old group (n = 7), 8 to 10 years of age. True transverse and midsagittal MRI images were used for pedicle (width and length), vertebral body (height, depth and width), and spinal canal area measurements. RESULTS The mean increase of the pedicle width and length was 0.7 mm (16%) and 3.2 mm (18%) from the infantile to the juvenile-young, and was 0.9 mm (15%) and 2.2 mm (11%) through the juvenile-old group. The mean increase of the vertebra body width, depth, and height were 3.6 mm (15%), 4.5 mm (27%), and 3.1 mm (27%), respectively, from the infantile to the juvenile-young, and were 2.9 mm (10%), 1.9 mm (9%) and 2.1 mm (15%), respectively, through the juvenile-old group. The mean increase of the spinal canal area was 41 mm (19%) from the infantile to the juvenile-young and was only 1.8 mm (0.7%) through the juvenile-old group. CONCLUSION The current study established the growth of the pedicle, spinal canal, and vertebral body in vivo in a sample of normal pediatric subjects. The vertebral growth rate in the infantile and the juvenile-young period was significantly greater than that in the juvenile-old period. Spinal canal growth is associated with the growth of the pedicle width and has little growth after the juvenile-young period. Pedicle screw fixation would be unlikely to influence the size of the spinal canal after the early juvenile period, but may disturb the pedicle growth in length.
Collapse
|
6
|
Gao B, Gao W, Chen C, Wang Q, Lin S, Xu C, Huang D, Su P. What is the Difference in Morphologic Features of the Thoracic Pedicle Between Patients With Adolescent Idiopathic Scoliosis and Healthy Subjects? A CT-based Case-control Study. Clin Orthop Relat Res 2017; 475:2765-2774. [PMID: 28766159 PMCID: PMC5638737 DOI: 10.1007/s11999-017-5448-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 07/11/2017] [Indexed: 01/31/2023]
Abstract
BACKGROUND Describing the morphologic features of the thoracic pedicle in patients with adolescent idiopathic scoliosis is necessary for placement of pedicle screws. Previous studies showed inadequate reliability owing to small sample size and heterogeneity of the patients surveyed. QUESTIONS/PURPOSES To use CT scans (1) to describe the morphologic features of 2718 thoracic pedicles from 60 female patients with Lenke Type 1 adolescent idiopathic scoliosis and 60 age-, sex-, and height-matched controls; and (2) to classify the pedicles in three types based on pedicle width and analyze the distribution of each type. METHODS A total of 2718 pedicles from 60 female patients with Lenke Type 1 adolescent idiopathic scoliosis and 60 matched female controls were analyzed via CT. All patients surveyed were diagnosed with adolescent idiopathic scoliosis, Lenke Type 1, at the First Affiliated Hospital of Sun Yat-sen University, and all underwent pedicle screw fixation between January 2008 and December 2013 with preoperative radiographs and CT images on file. We routinely obtained CT scans before these procedures; all patients who underwent surgery during that period had CT scans, and all were available for analysis here. Control subjects had CT scans for other clinical indications and had no abnormal findings of the spine. The control subjects were chosen to match patients in terms of age (15 ± 2.6 years versus 15 ± 2.6 years) and sex. Height of the two groups also was matched (154 ± 9 cm versus 155 ± 10 cm; mean difference, -1.06 cm; 95% CI, -1.24 to -0.81 cm; p < 0.001). Pedicle width and length were measured from T1 to T12. The thoracic spine was classified in four regions: apical vertebra in the structural curve (AV-SC), nonapical vertebra in the structural curve (NAV-SC), apical vertebra in the nonstructural curve (AV-NSC), and nonapical vertebra in the nonstructural curve (NAV-NSC). Pedicles were classified in three types: pedicle width less than 2 mm as Type I, 2 mm to 4 mm as Type II, and greater than 4 mm as Type III. Types I and II were defined as dysplastic pedicles. Paired t test, independent samples t test, one-way ANOVA, followed by Bonferroni's post hoc test and chi-square or Fisher's exact tests were used for statistical comparisons between patients and controls, as appropriate. RESULTS No difference was found between pedicle width on the convex side (PWv) and in controls (PWn), but pedicle width on the concave side (PWc) (4.99 ± 1.87 mm) was found to be narrower than PWv (6 ± 1.66 mm) and PWn (6 ± 1.45 mm). The variation degree of pedicle width (VDPW) was greatest in the AV-SC region (34% ± 37%), in comparison to AV-NSC (20% ± 25%) (mean difference, 14%; 95% CI, 1.15%-27%; p = 0.025), NAV-SC (17% ± 30%) (mean difference, 17%; 95% CI, 7%-27%; p < 0.001), and NAV-NSC (11% ± 24%) (mean difference, 24%; 95% CI, 13%-34%; p < 0.001). Dysplastic pedicles appeared more in patients with adolescent idiopathic scoliosis (22%; 293 of 1322) compared with controls (13%; 178 of 1396) (odds ratio [OR] = 0.51; 95% CI, 0.42-0.63; p < 0.001). In patients with adolescent idiopathic scoliosis, they commonly occurred on the concave side 34% (228 of 661) and on the AV-SC region (32%; 43 of 136). CONCLUSIONS Pedicle width on the concave side was narrower than pedicle width on the convex side and pedicle width in healthy control subjects. The apical vertebra in the structural curve was the most variegated region of the curve with the highest prevalence of dysplastic pedicles. CLINICAL RELEVANCE Our study can help surgeons perform preoperative assessments in females with adolescent idiopathic scoliosis, and with preoperative and intraoperative management for difficult pedicle screw placement. In particular, our results suggest that surgeons should exercise increased vigilance when selecting pedicle screw dimensions, especially in the concave aspect of the mid-thoracic curve, to avoid cortical breeches. Future studies should evaluate other Lenke types of adolescent idiopathic scoliosis, and males with adolescent idiopathic scoliosis.
Collapse
Affiliation(s)
- Bo Gao
- Department of Orthopaedics, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, China
| | - Wenjie Gao
- Department of Orthopaedics, The First Affiliated Hospital of Sun Yat-sen University, #58 Zhongshan Road II, Guangzhou, 510080 Guangdong China ,Department of Spine Surgery, Xi’an Honghui Hospital, Xi’an Jiaotong University, Xi’an, China
| | - Chong Chen
- Department of Orthopaedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Qinghua Wang
- Department of Orthopaedics, The First Affiliated Hospital of Sun Yat-sen University, #58 Zhongshan Road II, Guangzhou, 510080 Guangdong China
| | - Shaochun Lin
- Department of Radiology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Caixia Xu
- Research Centre for Translational Medicine, First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Dongsheng Huang
- Department of Orthopaedics, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, China
| | - Peiqiang Su
- Department of Orthopaedics, The First Affiliated Hospital of Sun Yat-sen University, #58 Zhongshan Road II, Guangzhou, 510080 Guangdong China ,Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080 China
| |
Collapse
|
7
|
The Azygos Vein Is at Potential Risk of Injury From Malpositioning of Left Thoracic Pedicle Screw in Thoracic Adolescent Idiopathic Scoliosis Patients. Spine (Phila Pa 1976) 2017; 42:E920-E925. [PMID: 28742737 DOI: 10.1097/brs.0000000000002000] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN A computed tomography study. OBJECTIVE To evaluate the changed position of azygos vein in patients with thoracic adolescent idiopathic scoliosis (AIS) and to analyze the potential risk of injury of azygos vein from thoracic pedicle screw placement in these patients. SUMMARY OF BACKGROUND DATA It has been widely recognized that the anatomic positions of structures adjacent to the vertebrae may change in patients with AIS. To date, no study had evaluated such change of azygos vein in patients with AIS. METHODS Twenty-five patients with thoracic AIS and 17 age-matched normal teenagers were included in the present study. Axial computed tomography images from T7 to T10 level were obtained to evaluate azygos vein-vertebral angle (defined as 0° when the azygos vein was located directly laterally to the left and 180° when directly laterally to the right). The percentage of azygos vein located in the direction of left screw passage was calculated to analyze the potential risk of injury from left pedicle screw placement. RESULTS The azygos vein-vertebral angles were significantly smaller in patients with AIS when compared with normal teenagers from T7 to T10 level (P < 0.001). The percentage of azygos vein at high risk of injury from left pedicle screw placement was 80% (20/25) at T7 level, 84% (21/25) at T8 level, 76% (19/25) at T9 level, and 72% (18/25) at T10 level in patients with AIS. No azygos vein was found to be at risk of injury from right pedicle screw placement in patients with AIS. The azygos vein was safe from pedicle screw placement on both sides in normal teenagers. CONCLUSION The changed relative anatomic position of azygos vein in patients with thoracic AIS places the azygos vein at high potential risk of injury from excessively long left pedicle screw placement. Spine surgeons should choose appropriate screw length to avoid anterior cortex perforation. LEVEL OF EVIDENCE 3.
Collapse
|
8
|
Brink RC, Schlösser TPC, Colo D, Vincken KL, van Stralen M, Hui SCN, Chu WCW, Cheng JCY, Castelein RM. Asymmetry of the Vertebral Body and Pedicles in the True Transverse Plane in Adolescent Idiopathic Scoliosis: A CT-Based Study. Spine Deform 2017; 5:37-45. [PMID: 28038692 DOI: 10.1016/j.jspd.2016.08.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 08/10/2016] [Indexed: 11/25/2022]
Abstract
STUDY DESIGN Cross-sectional. OBJECTIVES To quantify the asymmetry of the vertebral bodies and pedicles in the true transverse plane in adolescent idiopathic scoliosis (AIS) and to compare this with normal anatomy. SUMMARY OF BACKGROUND DATA There is an ongoing debate about the existence and magnitude of the vertebral body and pedicle asymmetry in AIS and whether this is an expression of a primary growth disturbance, or secondary to asymmetrical loading. METHODS Vertebral body asymmetry, defined as left-right overlap of the vertebral endplates (ie, 100%: perfect symmetry, 0%: complete asymmetry) was evaluated in the true transverse plane on CT scans of 77 AIS patients and 32 non-scoliotic controls. Additionally, the pedicle width, length, and angle and the length of the ideal screw trajectory were calculated. RESULTS Scoliotic vertebrae were on average more asymmetric than controls (thoracic: AIS 96.0% vs. controls 96.4%; p = .005, lumbar: 95.8% vs. 97.2%; p < .001) and more pronounced around the thoracic apex (95.8%) than at the end vertebrae (96.3%; p = .031). In the thoracic apex; the concave pedicle was thinner (4.5 vs. 5.4 mm; p < .001) and longer (20.9 vs. 17.9 mm; p < .001), the length of the ideal screw trajectory was longer (43.0 vs. 37.3 mm; p < .001), and the transverse pedicle angle was greater (12.3° vs. 5.7°; p < .001) than the convex one. The axial rotation showed no clear correlation with the asymmetry. CONCLUSIONS Even in non-scoliotic controls is a degree of vertebral body and pedicle asymmetry, but scoliotic vertebrae showed slightly more asymmetry, mostly around the thoracic apex. In contrast to the existing literature, there is no major asymmetry in the true transverse plane in AIS and no uniform relation between the axial rotation and vertebral asymmetry could be observed in these moderate to severe patients, suggesting that asymmetrical vertebral growth does not initiate rotation, but rather follows it as a secondary phenomenon. LEVEL OF EVIDENCE Level 4.
Collapse
Affiliation(s)
- Rob C Brink
- Department of Orthopaedic Surgery, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Tom P C Schlösser
- Department of Orthopaedic Surgery, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Dino Colo
- Department of Orthopaedic Surgery, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Koen L Vincken
- Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Marijn van Stralen
- Imaging Division, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Steve C N Hui
- Department of Imaging & Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Winnie C W Chu
- Department of Imaging & Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Jack C Y Cheng
- Department of Orthopaedics and Traumatology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - René M Castelein
- Department of Orthopaedic Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.
| |
Collapse
|
9
|
Jiang J, Qian BP, Zhu ZZ, Wang B, Yu Y, Qiu Y. Different potential risk of injury from thoracic pedicle screw insertion between left and right main-stem bronchus in Lenke 1 type adolescent idiopathic 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 2016; 25:1794-9. [DOI: 10.1007/s00586-016-4378-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 01/07/2016] [Accepted: 01/07/2016] [Indexed: 10/22/2022]
|
10
|
Peters JR, Chandrasekaran C, Robinson LF, Servaes SE, Campbell RM, Balasubramanian S. Age- and gender-related changes in pediatric thoracic vertebral morphology. Spine J 2015; 15:1000-20. [PMID: 25681580 DOI: 10.1016/j.spinee.2015.01.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 12/08/2014] [Accepted: 01/10/2015] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Although it is well known that the growth of thoracic spine changes significantly with age, gender, and vertebral level in the skeletally normal pediatric population, there have been very few studies attempting to comprehensively quantify such variations. Biomechanical and computational models of the growing thoracic spine have provided insight into safety and efficacy of surgical and noninvasive treatments for spinal deformity. However, many of these models only consider growth of the vertebral body and pedicles and assume a consistent growth rate for these structures across thoracic levels. PURPOSE To enhance the understanding of age-, gender-, and level-related growth dynamics of the pediatric thoracic spine by comprehensively quantifying the thoracic vertebral morphology for subjects between 1 and 19 years. STUDY DESIGN A retrospective computed tomography (CT) image analysis study. METHODS Retrospectively obtained chest CT scans from 100 skeletally normal pediatric subjects (45 males and 55 females between the ages 1 and 19 years) were digitally reconstructed using medical imaging software. Surface point clouds of thoracic vertebrae were extracted and 26 vertebral geometry parameters were measured using 25 semiautomatically identified surface landmarks and anatomical slices from each thoracic vertebra (T1-T12). Data were assessed for normality, symmetry, and age-, gender-, and level-related differences in geometric measures and growth. Linear regression was performed to estimate of the rates of variation with age for each measurement. RESULTS Asymmetries (bilateral, superior-inferior, and anteroposterior) were observed in vertebral body heights, end plate widths and depths, and interfacet widths. Within genders, significant interlevel differences were observed for all geometric measures, and significant differences in the rates of growth were found across thoracic levels for most parameters. Significant differences were observed between genders for pedicle, spinous process, and facet measurements. Growth rates of the pedicles and vertebral bodies were also found to vary significantly between genders. CONCLUSIONS The rates of growth for most thoracic vertebral structures varied between genders and across vertebral levels. These growth rates followed trends similar to those of their associated vertebral dimensions and this indicates that, across levels and between genders, larger vertebral structures grow at faster rates, whereas smaller structures grow at a slower rate. Such level- and gender-specific information could be used to inform clinical decisions about spinal deformity treatment and adapted for use in biomechanical and computational modeling of thoracic growth and growth modulation.
Collapse
Affiliation(s)
- James R Peters
- School of Biomedical Engineering, Science and Health Systems, Drexel University, 3141 Chestnut St, Bossone 718, Philadelphia, PA 19104, USA
| | - Charanya Chandrasekaran
- School of Biomedical Engineering, Science and Health Systems, Drexel University, 3141 Chestnut St, Bossone 718, Philadelphia, PA 19104, USA
| | - Lucy F Robinson
- Department of Epidemiology and Biostatistics, School of Public Health, Drexel University, Nesbitt Hall, 3215 Market St. Philadelphia, PA 19104, USA
| | - Sabah E Servaes
- Department of Radiology, The Children's Hospital of Philadelphia, 34th St and Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Robert M Campbell
- Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, 34th St and Civic Center Boulevard, Philadelphia, PA 19104, USA
| | - Sriram Balasubramanian
- School of Biomedical Engineering, Science and Health Systems, Drexel University, 3141 Chestnut St, Bossone 718, Philadelphia, PA 19104, USA.
| |
Collapse
|
11
|
Influence of implant rod curvature on sagittal correction of scoliosis deformity. Spine J 2014; 14:1432-9. [PMID: 24275616 DOI: 10.1016/j.spinee.2013.08.042] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 06/27/2013] [Accepted: 08/23/2013] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Deformation of in vivo-implanted rods could alter the scoliosis sagittal correction. To our knowledge, no previous authors have investigated the influence of implanted-rod deformation on the sagittal deformity correction during scoliosis surgery. PURPOSE To analyze the changes of the implant rod's angle of curvature during surgery and establish its influence on sagittal correction of scoliosis deformity. STUDY DESIGN A retrospective analysis of the preoperative and postoperative implant rod geometry and angle of curvature was conducted. PATIENT SAMPLE Twenty adolescent idiopathic scoliosis patients underwent surgery. Average age at the time of operation was 14 years. OUTCOME MEASURES The preoperative and postoperative implant rod angle of curvature expressed in degrees was obtained for each patient. METHODS Two implant rods were attached to the concave and convex side of the spinal deformity. The preoperative implant rod geometry was measured before surgical implantation. The postoperative implant rod geometry after surgery was measured by computed tomography. The implant rod angle of curvature at the sagittal plane was obtained from the implant rod geometry. The angle of curvature between the implant rod extreme ends was measured before implantation and after surgery. The sagittal curvature between the corresponding spinal levels of healthy adolescents obtained by previous studies was compared with the implant rod angle of curvature to evaluate the sagittal curve correction. The difference between the postoperative implant rod angle of curvature and normal spine sagittal curvature of the corresponding instrumented level was used to evaluate over or under correction of the sagittal deformity. RESULTS The implant rods at the concave side of deformity of all patients were significantly deformed after surgery. The average degree of rod deformation Δθ at the concave and convex sides was 15.8° and 1.6°, respectively. The average preoperative and postoperative implant rod angle of curvature at the concave side was 33.6° and 17.8°, respectively. The average preoperative and postoperative implant rod angle of curvature at the convex side was 25.5° and 23.9°, respectively. A significant relationship was found between the degree of rod deformation and preoperative implant rod angle of curvature (r=0.60, p<.005). The implant rods at the convex side of all patients did not have significant deformation. The results indicate that the postoperative sagittal outcome could be predicted from the initial rod shape. CONCLUSIONS Changes in implant rod angle of curvature may lead to over- or undercorrection of the sagittal curve. Rod deformation at the concave side suggests that corrective forces acting on that side are greater than the convex side.
Collapse
|
12
|
Sarwahi V, Sugarman EP, Wollowick AL, Amaral TD, Lo Y, Thornhill B. Prevalence, Distribution, and Surgical Relevance of Abnormal Pedicles in Spines with Adolescent Idiopathic Scoliosis vs. No Deformity: A CT-Based Study. J Bone Joint Surg Am 2014; 96:e92. [PMID: 24897749 DOI: 10.2106/jbjs.m.01058] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND A thorough understanding of pedicle morphology is necessary for pedicle screw placement. Previous studies classifying pedicle morphology, to our knowledge, have neither discussed the range of abnormal morphology nor correlated patient or curve characteristics with abnormal morphology to identify at-risk pedicles. METHODS With the use of computed tomography (CT) images, we analyzed a total of 6116 pedicles from ninety-five patients without spinal deformity (forty-two females and fifty-three males) and ninety-one patients with adolescent idiopathic scoliosis (AIS) (sixty-eight females and twenty-three males). Pedicle morphology was classified as: Type A, a cancellous channel of >4 mm; Type B, a cancellous channel of 2 to 4 mm; Type C, a cortical channel of ≥2 mm; or Type D, a cortical or cancellous channel of <2 mm. Types B, C, and D were defined as abnormal. Patient demographic data and pedicle distribution were assessed for prevalence and likelihood of abnormal pedicle morphology. Postoperative CT images from fifty-nine patients with AIS were used to assess screw placement. RESULTS There was a significantly higher rate of abnormal pedicles in patients with AIS (p = 0.001). More abnormal pedicles were located in the thoracic spine compared with the lumbar spine both in patients without deformity (13.3% versus 2.0%) and patients with AIS (31.9% versus 2.4%). Significantly more abnormal pedicles were located on the concavity (p < 0.001), within the periapical region (p = 0.02), and on the apex of the curve (p = 0.03). Three times as many pedicle screws were misplaced in abnormal pedicles compared with normal pedicles (21% versus 7%). CONCLUSIONS Our study found a significantly higher prevalence of abnormal pedicles in the patients with AIS. Of the abnormal pedicles in these patients, most were in the thoracic spine, on the concave side, and in the periapical and apical regions. CLINICAL RELEVANCE Knowledge of abnormal pedicles may enable surgeons to anticipate and plan for difficult screw placement and further decrease risk to the patient.
Collapse
Affiliation(s)
- Vishal Sarwahi
- Department of Orthopaedic Surgery, Montefiore Medical Center, The Albert Einstein College of Medicine, 3400 Bainbridge Avenue, 6th Floor, Bronx, NY 10467. E-mail address for V. Sarwahi: . E-mail address for E.P. Sugarman: . E-mail address for A.L. Wollowick: . E-mail address for T.D. Amaral:
| | - Etan P Sugarman
- Department of Orthopaedic Surgery, Montefiore Medical Center, The Albert Einstein College of Medicine, 3400 Bainbridge Avenue, 6th Floor, Bronx, NY 10467. E-mail address for V. Sarwahi: . E-mail address for E.P. Sugarman: . E-mail address for A.L. Wollowick: . E-mail address for T.D. Amaral:
| | - Adam L Wollowick
- Department of Orthopaedic Surgery, Montefiore Medical Center, The Albert Einstein College of Medicine, 3400 Bainbridge Avenue, 6th Floor, Bronx, NY 10467. E-mail address for V. Sarwahi: . E-mail address for E.P. Sugarman: . E-mail address for A.L. Wollowick: . E-mail address for T.D. Amaral:
| | - Terry D Amaral
- Department of Orthopaedic Surgery, Montefiore Medical Center, The Albert Einstein College of Medicine, 3400 Bainbridge Avenue, 6th Floor, Bronx, NY 10467. E-mail address for V. Sarwahi: . E-mail address for E.P. Sugarman: . E-mail address for A.L. Wollowick: . E-mail address for T.D. Amaral:
| | - Yungtai Lo
- Department of Epidemiology and Population Health, The Albert Einstein College of Medicine, Jack and Pearl Resnick Campus, 1300 Morris Park Avenue, Block, Room 341, Bronx, NY 10461. E-mail address:
| | - Beverly Thornhill
- Department of Radiology, Montefiore Medical Center, The Albert Einstein College of Medicine, 111 East 210th Street, Bronx, NY 10467. E-mail address:
| |
Collapse
|
13
|
Hong JY, Suh SW, Easwar TR, Hong SJ, Yoon YC, Kang HJ. Clinical anatomy of vertebrae in scoliosis: global analysis in four different diseases by multiplanar reconstructive computed tomography. Spine J 2013; 13:1510-20. [PMID: 23992938 DOI: 10.1016/j.spinee.2013.06.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 03/30/2013] [Accepted: 06/14/2013] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Few accurate analyses of clinically useful vertebral anatomy have been conducted, and most have focused on thoracic idiopathic scoliosis. PURPOSE To evaluate the different anatomic characteristics in scoliosis by disease type and level. STUDY DESIGN Observational cohort study. PATIENT SAMPLE Forty-eight patients with scoliosis were included in this study. OUTCOME MEASURES Subjects underwent computed tomography (CT) of the whole spine. METHODS Forty-eight patients with scoliosis were included in this study: 15 adolescent idiopathic, 11 cerebral palsy (CP), 10 muscular dystrophy (MD), and 12 congenital (CG) scoliosis patients with similar demographics. Subjects underwent CT of the whole spine, preoperatively. Eight anatomic parameters were measured in multiplanar reconstructive CT images, and statistical analysis was performed to investigate differences. RESULTS In general, values in the anatomic parameters were similar for the four diseases. Each parameter showed the unique change pattern according to the spinal level regardless of curvature shape, direction, or magnitude. In particular, chord length (CL) in MD and CG scoliosis was lower than in adolescent idiopathic scoliosis (AIS) and CP, and pedicle rib unit length was lower in CG scoliosis than in the other diseases (p<.05). Comparisons of convex and concave anatomies in AIS showed that inner pedicle width (PWI) and outer pedicle width (PWO) were wider for convex side, CL, pedicle width, and transverse pedicle angle were greater for concave side (p<.05), and differences were more significant at apices. However, in CP, PWI and PWO were similar between convex and concaves sides (p>.05). Although PWI and PWO were wider for convex sides and CL and pedicle length were greater for concave sides in MD (p<.05), differences were less significant at apices. Particularly, CG scoliosis showed severely deformed anatomy, with differences of seven parameters at apical vertebrae (p<.05). CONCLUSION Clinical anatomies of vertebrae in scoliosis were found to differ significantly at different levels and in terms of convexity and disease type.
Collapse
Affiliation(s)
- Jae-Young Hong
- Department of Orthopedics, Korea University Ansan Hospital, Gojan Dong, Danwon Gu, Ansan 425-707, Republic of Korea.
| | | | | | | | | | | |
Collapse
|
14
|
Kubota K, Doi T, Murata M, Kobayakawa K, Matsumoto Y, Harimaya K, Shiba K, Hashizume M, Iwamoto Y, Okada S. Disturbance of rib cage development causes progressive thoracic scoliosis: the creation of a nonsurgical structural scoliosis model in mice. J Bone Joint Surg Am 2013; 95:e130. [PMID: 24048561 DOI: 10.2106/jbjs.l.01381] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND The pathomechanism underlying idiopathic scoliosis remains unclear, and, to our knowledge, a consistent and relevant animal model has not been established previously. The goal of this study was to examine whether a disturbance of rib cage development is a causative factor for scoliosis and to establish a nonsurgical mouse model of progressive scoliosis. METHODS To examine the relationship between rib cage development and the pathogenesis of progressive scoliosis, a plastic restraint limiting anteroposterior rib cage development was placed on the chest of four-week-old mice. All mice were evaluated with whole-spine radiographs, and the severity of scoliosis was consecutively measured. The rib cage rotation angle and the anteroposterior chest dimension were measured with use of micro-computed tomography scanning. To examine whether the imbalanced load transmission through the ribs to the vertebral body was involved in our model, we performed a rib-neck osteotomy in a subgroup of the mice. RESULTS The thoracic restraint did not provoke spinal curvature immediately after it was applied, but nine of ten mice that wore the restraint but did not have rib osteotomy gradually developed progressive scoliosis. Radiographs and computed tomography images showed a right thoracic curvature, vertebral rotation, and narrow chest in the mice that had worn the restraint for eleven weeks but did not have rib osteotomy even after the restraint was removed. The anteroposterior chest dimension was significantly correlated with both the curve magnitude and the rib cage rotation angle. The progression of spinal deformity was observed only during the adolescent growth spurt, and it plateaued thereafter. The left-side rib osteotomy led to the development of progressive left-thoracic curvature, whereas the bilateral rib osteotomy did not cause scoliosis, even with restraint wear. CONCLUSIONS We established a nonsurgical experimental model of progressive scoliosis and also demonstrated that a rib cage deformity with an imbalanced load to the vertebral body resulted in progressive structural scoliosis.
Collapse
Affiliation(s)
- Kensuke Kubota
- Departments of Orthopaedic Surgery (K. Kubota, K. Kobayakawa, Y.M., K.H., Y.I.) and Advanced Medical Initiatives (M.M., M.H., S.O.), Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582. E-mail address fro K. Kubota: . E-mail address for M. Murata: . E-mail address for K. Kobyakawa: . E-mail address for Y. Matsumoto: . E-mail address for K. Harimaya: . E-mail address for M. Hashizume: . E-mail address for Y. Iwamoto:
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Different proximal thoracic curve patterns have different relative positions of esophagus to spine in adolescent idiopathic scoliosis: a computed tomography study. Spine (Phila Pa 1976) 2012; 37:193-9. [PMID: 21681132 DOI: 10.1097/brs.0b013e3182285fb9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN A computed tomography (CT) study. OBJECTIVE To evaluate the changed relative positions of esophagus in proximal thoracic (PT) curves of adolescent idiopathic scoliosis (AIS) patients and analyze the potential risks of esophageal injuries from thoracic pedicle screw (TPS) insertion. SUMMARY OF BACKGROUND DATA Translation and rotation of the vertebrae could lead to altered relative positions of surrounding vital structures in AIS patients. The changed positions of aorta and spinal cord in main thoracic (MT) curve have been comprehensively investigated; however, no studies have analyzed the relative position of esophagus in PT curve. METHODS Twenty patients with complete proximal thoracic (CPT group) curve, 22 patients with fractional proximal thoracic (FPT group) curve, and 14 normal patients with a straight spine (normal group) were included. Axial CT images from T2 to T5 at the midvertebral body level were obtained to evaluate esophagus-vertebral angle (EVA, defined as 0° when the esophagus was located directly lateral to the left, 90° when strictly anterior, and 180° when directly lateral to the right). The percentages of esophagus in the direction of screw passage were calculated to analyze potential risks of esophageal injuries during TPS insertion. RESULTS EVA in the FPT group was significantly smaller than that in the normal group (P < 0.05), whereas EVA in the CPT group was significantly greater than that in the normal group (P < 0.05) at each level. The esophagus was located approximately anterior to the vertebral body in the normal group but shifted anterolaterally to the right in the CPT group and anterolaterally to the left in the FPT group. The esophagus was at a high risk of injury with right anterior penetrated TPS in the CPT group and was at a high risk of injury with left anterior penetrated TPS in the FPT group. CONCLUSION Different anatomic patterns of PT curves could cause different altered positions of esophagus relative to spine and result in different potential risks of esophageal injuries during TPS insertion. Spine surgeons should choose appropriate pedicle screw length to avoid anterior cortical perforation in the PT region of AIS patients.
Collapse
|
16
|
Chu WCW, Rasalkar DD, Cheng JCY. Asynchronous neuro-osseous growth in adolescent idiopathic scoliosis--MRI-based research. Pediatr Radiol 2011; 41:1100-11. [PMID: 20689947 DOI: 10.1007/s00247-010-1778-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Revised: 05/26/2010] [Accepted: 05/31/2010] [Indexed: 11/26/2022]
Abstract
Adolescent idiopathic scoliosis (AIS) is a common worldwide problem and has been treated for many decades; however, there still remain uncertain areas about this disorder. Its involvement and impact on different parts of the human body remain underestimated due to lack of technology in imaging for objective assessment in the past. The advances in imaging technique and image analysis technology have provided a novel approach for the understanding of the phenotypic presentation of neuro-osseous changes in AIS patients as compared with normal controls. This review is the summary of morphological assessment of the skeletal and nervous systems in girls with AIS based on MRI. Girls with AIS are found to have morphological differences in multiple areas including the vertebral column, spinal cord, skull and brain when compared with age- and sex-matched normal controls. Taken together, the abnormalities in the skeletal system and nervous system of AIS are likely to be inter-related and reflect a systemic process of asynchronous neuro-osseous growth. The current knowledge about the anatomical changes in AIS has important implications with respect to the understanding of fundamental pathomechanical processes involved in the evolution of the scoliotic deformity.
Collapse
Affiliation(s)
- Winnie C W Chu
- Department of Diagnostic Radiology & Organ Imaging, The Chinese University of Hong Kong, Hong Kong, SAR, China.
| | | | | |
Collapse
|
17
|
Abstract
BACKGROUND Unilateral pedicle screw epiphysiodesis of the neurocentral synchondrosis (NCS) can produce asymmetric growth of the synchondrosis to create scoliosis in an immature animal model. QUESTIONS/PURPOSES We asked whether a preexisting experimentally created scoliosis could be limited and corrected by modulating the growth of the faster-growing NCS by a similar method. METHODS Nine 1-month-old pigs were assigned to each of three groups: (1) a sham group in which three animals received a sham operation but without a pedicle screw fixation; (2) an experimental group with double right pedicle screws placed across the NCS from T7 to T14 (scoliosis-untreated); and (3) an experimental group treated in the same way except a second set of double pedicle screws was placed in the left pedicles 6 weeks after the screws were placed on the right (scoliosis-treated). All animals were euthanized at 17 weeks, and radiographs and axial CT images of the spine were obtained. RESULTS A scoliotic curve was not seen in any of the animals in the sham group, in three of three in the scoliosis-untreated group with an average of 34°, and in three of three in the scoliosis-treated group with an average of 20°. In comparison to the scoliosis-untreated group, the second set of pedicle screws produced a 41% correction of the scoliosis. CONCLUSIONS We found the pedicle screw inhibited the overgrowth of the NCS to prevent further curve progression and obtained some correction of the deformity. The NCS screw epiphysiodesis can create and reverse scoliosis in an immature pig model.
Collapse
|
18
|
Adam CJ, Askin GN. Lateral bone density variations in the scoliotic spine. Bone 2009; 45:799-807. [PMID: 19563925 DOI: 10.1016/j.bone.2009.06.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Revised: 05/17/2009] [Accepted: 06/22/2009] [Indexed: 11/26/2022]
Abstract
Adolescent Idiopathic Scoliosis (AIS) is the most common deformity of the spine, affecting 2-4% of the population. Previous studies have shown that the vertebrae in scoliotic spines undergo abnormal shape changes, however there has been little exploration of how scoliosis affects bone density distribution within the vertebrae. In this study, existing CT scans of 53 female idiopathic scoliosis patients with right-sided main thoracic curves were used to measure the lateral (right to left) bone density profile at mid-height through each vertebral body. Five key bone density profile measures were identified from each normalized bone density distribution, and multiple regression analysis was performed to explore the relationship between bone density distribution and patient demographics (age, height, weight, body mass index (BMI), skeletal maturity, time since Menarche, vertebral level, and scoliosis curve severity). Results showed a marked convex/concave asymmetry in bone density for vertebral levels at or near the apex of the scoliotic curve. At the apical vertebra, mean bone density at the left side (concave) cortical shell was 23.5% higher than for the right (convex) cortical shell, and cancellous bone density along the central 60% of the lateral path from convex to concave increased by 13.8%. The centre of mass of the bone density profile at the thoracic curve apex was located 53.8% of the distance along the lateral path, indicating a shift of nearly 4% toward the concavity of the deformity. These lateral bone density gradients tapered off when moving away from the apical vertebra. Multi-linear regressions showed that the right cortical shell peak bone density is significantly correlated with skeletal maturity, with each Risser increment corresponding to an increase in mineral equivalent bone density of 4-5%. There were also statistically significant relationships between patient height, weight and BMI, and the gradient of cancellous bone density along the central 60% of the lateral path. Bone density gradient is positively correlated with weight, and negatively correlated with height and BMI, such that at the apical vertebra, a unit decrease in BMI corresponds to an almost 100% increase in bone density gradient.
Collapse
Affiliation(s)
- Clayton J Adam
- Paediatric Spine Research Group, Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia.
| | | |
Collapse
|
19
|
Zhang H, Sucato DJ. Unilateral pedicle screw epiphysiodesis of the neurocentral synchondrosis. Production of idiopathic-like scoliosis in an immature animal model. J Bone Joint Surg Am 2008; 90:2460-9. [PMID: 18978416 DOI: 10.2106/jbjs.g.01493] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND The neurocentral synchondrosis plays a role in the growth of the spine. The goal of this study was to determine whether asymmetric epiphysiodesis of this synchondrosis creates a scoliotic deformity in a growing-animal model and to correlate curve magnitude with the degree of closure of the synchondrosis. METHODS Two-month-old pigs were assigned to three groups. In the control group, two animals received a sham operation without pedicle screw fixation; in the single-screw group, three animals were treated with a single right transpedicular screw placed across the neurocentral synchondrosis from T7 to T14; and in the double-screw group, three animals were treated in the same way as the previous group except that two screws were placed in each pedicle. The animals were killed at six months, and radiographs and axial computed tomography images of the spine were obtained. Histomorphometric analyses were performed to grade the synchondrosis at each level. RESULTS A scoliotic curve was seen in none of the animals in the control group, in one of the three in the single-screw group, and in all three in the double-screw group (30 degrees, 42 degrees, and 42 degrees). Vertebral rotation in the axial plane occurred toward the screw side and was significantly greater in the double-screw group (mean, 15.2 degrees) than in the single-screw (mean, 6.1 degrees) and control (0 degrees) groups (p < 0.001). There was no difference in morphology between the left and right pedicles in the control group. The left pedicle was 9% longer than the right (screw-treated) pedicle in the single-screw group, and it was 22% longer than the right pedicle in the double-screw group. Closure of the neurocentral synchondrosis was greatest in the double-screw group (>75% closure) compared with the single-screw group (<50% closure) (p < 0.0001) and the control group (no closure) (p < 0.0001), and closure correlated with the magnitude of the coronal curve (p = 0.001). CONCLUSIONS Unilateral transpedicular screw fixation that traverses the neurocentral synchondrosis in a growing-pig model can produce asymmetric growth of the synchondrosis to create scoliosis with the convexity on the side of the screw fixation. Double pedicle screws provided a greater epiphysiodesis effect on the neurocentral synchondrosis, which correlated with a greater degree of scoliosis.
Collapse
Affiliation(s)
- Hong Zhang
- Texas Scottish Rite Hospital for Children, 2222 Welborn Street, Dallas, TX 75219, USA.
| | | |
Collapse
|
20
|
Abstract
Adolescent idiopathic scoliosis (AIS) affects 1-3% of children in the at-risk population of those aged 10-16 years. The aetiopathogensis of this disorder remains unknown, with misinformation about its natural history. Non-surgical treatments are aimed to reduce the number of operations by preventing curve progression. Although bracing and physiotherapy are common treatments in much of the world, their effectiveness has never been rigorously assessed. Technological advances have much improved the ability of surgeons to safely correct the deformity while maintaining sagittal and coronal balance. However, we do not have long-term results of these changing surgical treatments. Much has yet to be learned about the general health, quality of life, and self-image of both treated and untreated patients with AIS.
Collapse
Affiliation(s)
- Stuart L Weinstein
- Department of Orthopaedic Surgery and Rehabilitation, University of Iowa, Iowa City, Iowa, IA 52242, USA.
| | | | | | | | | |
Collapse
|
21
|
Pain and disability correlated with disc degeneration via magnetic resonance imaging in scoliosis patients. 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 2007; 17:240-9. [PMID: 17973128 DOI: 10.1007/s00586-007-0530-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2007] [Revised: 07/28/2007] [Accepted: 10/13/2007] [Indexed: 10/22/2022]
Abstract
Prior imaging studies of scoliosis patients attempted to demonstrate a relationship between plain radiographic curve patterns and curve progression and pain, or used magnetic resonance imaging (MRI) to focus on spinal cord abnormalities. Pain in scoliosis patients may differ from nondeformity patients, yet may still be discogenic. The purpose of this study was to assess the possible relationship of degenerative disc findings on MRI to scoliosis patients' pain. This prospective study enrolled scoliosis and control patients, all of whom had assessment for back pain (visual analog scale) and disability (Oswestry Index) and spinal MRI to identify prevalence and distribution of degenerative disc findings. Specifically, we assessed 60 consecutive pediatric and adult idiopathic scoliosis patients who had progressed to surgical treatment, 60 age- and gender-matched asymptomatic controls, and 172 nondeformity symptomatic degenerative disc disease patients who had progressed to surgical treatment. All subjects had independent analysis of their preoperative MRI for disc degeneration, disc herniation, Schmorl's nodes, and inflammatory end plate changes. Imaging findings of the scoliosis patients were compared to those from asymptomatic and symptomatic control groups. Our results found that both pediatric and adult scoliosis patients had significantly more pain and disability than did asymptomatic controls (P < 0.001). The adult idiopathic scoliosis patients had pain and disability similar to those of surgical degenerative disc disease control groups. Disc degeneration and herniation (contained) were not related to pain. However, in the pediatric scoliosis patients, those with Schmorl's nodes often had greater pain than those without (P = 0.01). Adults with painful scoliosis, typically occurring at the apex of the scoliosis or at the lumbosacral junction, had a significantly higher frequency of inflammatory end plate changes on MRI than did controls (P < 0.001). Prior studies have demonstrated a correlation of inflammatory end plate changes to lumbar discogenic pain. In conclusions, scoliosis patients who have progressed to surgical intervention, pediatric patients have varying degrees of pain, and those with Schmorl's nodes may be at greater risk for pain. Adult scoliosis patients have multifactorial pain of which one component may be related to degeneration of the lower lumbar discs similar to that in nondeformity patients. Additionally, adult scoliosis patients may have MRI findings consistent with discogenic pain at the apex of their curvature, most commonly at the proximal lumbar levels.
Collapse
|