1
|
Meng B, Zhao X, Wang XL, Wang J, Xu C, Lei W. Does the novel artificial cervical joint complex resolve the conflict between stability and mobility after anterior cervical surgery? a finite element study. Front Bioeng Biotechnol 2024; 12:1400614. [PMID: 38887613 PMCID: PMC11180832 DOI: 10.3389/fbioe.2024.1400614] [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: 03/13/2024] [Accepted: 05/10/2024] [Indexed: 06/20/2024] Open
Abstract
Background and objective Our group has developed a novel artificial cervical joint complex (ACJC) as a motion preservation instrument for cervical corpectomy procedures. Through finite element analysis (FEA), this study aims to assess this prosthesis's mobility and stability in the context of physiological reconstruction of the cervical spine. Materials and methods A finite element (FE)model of the subaxial cervical spine (C3-C7) was established and validated. ACJC arthroplasty, anterior cervical corpectomy and fusion (ACCF), and two-level cervical disc arthroplasty (CDA) were performed at C4-C6. Range of motion (ROM), intervertebral disc pressure (IDP), facet joint stress (FJS), and maximum von Mises stress on the prosthesis and vertebrae during loading were compared. Results Compared to the intact model, the ROM in all three surgical groups demonstrated a decline, with the ACCF group exhibiting the most significant mobility loss, and the highest compensatory motion in adjacent segments. ACJC and artificial cervical disc prosthesis (ACDP) well-preserved cervical mobility. In the ACCF model, IDP and FJS in adjacent segments increased notably, whereas the index segments experienced the most significant FJS elevation in the CDA model. The ROM, IDP, and FJS in both index and adjacent segments of the ACJC model were intermediate between the other two. Stress distribution of ACCF instruments and ACJC prosthesis during the loading process was more dispersed, resulting in less impact on the adjacent vertebrae than in the CDA model. Conclusion The biomechanical properties of the novel ACJC were comparable to the ACCF in constructing postoperative stability and equally preserved physiological mobility of the cervical spine as CDA without much impact on adjacent segments and facet joints. Thus, the novel ACJC effectively balanced postoperative stability with cervical motion preservation.
Collapse
Affiliation(s)
- Bing Meng
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Xi’an, Shaanxi Province, China
| | - Xiong Zhao
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Xi’an, Shaanxi Province, China
| | - Xin-Li Wang
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Xi’an, Shaanxi Province, China
| | - Jian Wang
- Department of Orthopedics, Affiliated Hospital of NCO School of Army Medical University, Shijiazhuang, Hebei Province, China
| | - Chao Xu
- Department of Knee Joint Surgery, Honghui Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, China
- Department of Health Statistics, Faculty of Preventive Medicine, the Air Force Military Medical University, Xi’an, Shaanxi, China
| | - Wei Lei
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Xi’an, Shaanxi Province, China
| |
Collapse
|
2
|
Wing-Yuk Chan R, Chiang YH, Yang YA, Chen YY, Tsou YS. One-Year Follow-Up Study on Assessing the Range of Segmental Motion and Clinical Outcomes Following Cervical Disc Arthroplasty for Treatment of Severe Cervical Disc Degeneration. World Neurosurg 2024; 183:e276-e281. [PMID: 38128758 DOI: 10.1016/j.wneu.2023.12.079] [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: 11/13/2023] [Revised: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 12/23/2023]
Abstract
BACKGROUND Though previous studies have documented various clinical outcomes after cervical arthroplasty for degenerative cervical disc disease, none of them reported the impact of cervical arthroplasty on severe cervical disc degeneration (CDD). METHODS This retrospective cohort study included severe 40 CDD (C3-C7) patients who underwent single-level cervical arthroplasty using ProDisc-C between January 2017 and December 2019. After surgical intervention, the range of motion (ROM) was determined, whereas clinical outcomes were measured in terms of the Visual Analogue Scale (VAS) and Neck Disability Index (NDI) to evaluate neck pain and disability, respectively. RESULTS Compared to the mean preoperative ROM (6.57 ± 4.85°), the cervical dynamic ROM was increased 3 months after cervical arthroplasty, and the increment was maintained for at least 1 year. The increased ROM is attributed to the extension and not flexion components. The mean preoperative ROM of 6.57 ± 4.85° significantly increased to 11.67 ± 4.98° (P = 0.0005), 10.05 ± 5.18° (P = 0.0426) and 10.46 ± 4.73° (P = 0.0247) after 3 months, 6 months and 1 year, respectively. The extension ROM also revealed a similar trend. VAS for neck and arm decreased from 7.4 and 6.6 to 1.4 and 1.2, respectively. Consistently, the preoperative mean Neck Disability Index (NDI) score of 27.6 decreased to 14.6. We recorded a case of device subsidence, but without extrusion. CONCLUSIONS Cervical arthroplasty can improve clinical outcomes and restore ROM in severe CDD patients.
Collapse
Affiliation(s)
- Ryan Wing-Yuk Chan
- Department of Neurosurgery, Taipei Medical University Hospital, Taipei, Taiwan; Taipei Neuroscience Institute, Taipei Medical University, Taipei, Taiwan; Ph.D. Program in Medical Neuroscience, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Yung-Hsiao Chiang
- Department of Neurosurgery, Taipei Medical University Hospital, Taipei, Taiwan; Taipei Neuroscience Institute, Taipei Medical University, Taipei, Taiwan; Department of Surgery, School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yi-An Yang
- Department of Nursing, Taipei Medical University Hospital, Taipei, Taiwan
| | - Yi-Yu Chen
- Department of Neurosurgery, Taipei Medical University Hospital, Taipei, Taiwan; Taipei Neuroscience Institute, Taipei Medical University, Taipei, Taiwan; Department of Nursing, Taipei Medical University Hospital, Taipei, Taiwan
| | - Yi-Syue Tsou
- Department of Neurosurgery, Taipei Medical University Hospital, Taipei, Taiwan; Taipei Neuroscience Institute, Taipei Medical University, Taipei, Taiwan; Ph.D. Program in Medical Neuroscience, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan.
| |
Collapse
|
3
|
Khalid SI, Mirpuri P, Thomson K, Elsamadicy A, Massaad E, Deysher D, Khilwani H, Adogwa O, Shin JH, Mehta AI. Outcomes Following 2-Level Cervical Interventions with Cage-and-Plate, Zero-Profile, or Arthroplasty Constructs. World Neurosurg 2023; 180:e607-e617. [PMID: 37797683 DOI: 10.1016/j.wneu.2023.09.117] [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: 07/09/2023] [Revised: 09/26/2023] [Accepted: 09/27/2023] [Indexed: 10/07/2023]
Abstract
BACKGROUND Though cage-and-plate constructs are widely used for disk height restoration in surgery for cervical disc disease, concerns over range of motion limitations and adjacent disc space violations have fueled the development of artificial disc and zero-profile constructs. This study investigated the outcomes of patients undergoing two-level cervical interventions via arthroplasty, cage-and-plate, or zero-profile constructs. METHODS Patients undergoing two-level anterior cervical procedures between 2010 and 2020 were identified using an all-payer claims database. Logistic regression models were utilized to develop criteria for a 1:1:1-exact match procedure. The primary outcome was the need for additional surgery within 30 months, and the secondary outcomes included medical and surgical complications observed within 30 days of index intervention. P values < 0.05 were considered statistically significant. RESULTS 133,831 patients were identified as undergoing two-level anterior cervical interventions. Seven thousand three hundred seventy-one records were analyzed through a 1:1:1 match. Patients who received zero-profile versus cage-and-plate constructs had significantly decreased odds of requiring additional surgery within 30 months (Odds Ratio [OR] 0.64; 95% Confidence Interval [CI] 0.51-0.81). However, postoperative medical complications were increased among patients who received zero-profile constructs compared to cage-and-plate (OR 1.59; 95%CI 1.07-2.37). Patients who underwent arthroplasty also had decreased odds for additional surgery versus cage-and-plate (OR 0.75; 95%CI 0.60-0.93). There was no significant difference between arthroplasty and cage-and-plate constructs in developing postoperative surgical or medical complications. CONCLUSIONS Among patients undergoing two-level interventions, cage-and-plate constructs were associated with increased odds of additional surgery within 30 months following index procedures when compared to zero-profile constructs or arthroplasty.
Collapse
Affiliation(s)
- Syed I Khalid
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois, USA.
| | - Pranav Mirpuri
- Chicago Medical School, Rosalind Franklin School of Medicine and Science, North Chicago, Illinois, USA
| | - Kyle Thomson
- Chicago Medical School, Rosalind Franklin School of Medicine and Science, North Chicago, Illinois, USA
| | - Aladine Elsamadicy
- Department of Neurosurgery, Yale School of Medicine, New Haven, Connecticut, USA
| | - Elie Massaad
- Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Daniel Deysher
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Harsh Khilwani
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Owoicho Adogwa
- Department of Neurosurgery, University of Cincinnati School of Medicine, Cincinnati, Ohio, USA
| | - John H Shin
- Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Ankit I Mehta
- Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois, USA
| |
Collapse
|
4
|
Khalaf K, Nikkhoo M. Comparative biomechanical analyses of lower cervical spine post anterior fusion versus intervertebral disc arthroplasty: A geometrically patient-specific poroelastic finite element investigation. J Orthop Translat 2022; 36:33-43. [PMID: 35891924 PMCID: PMC9293956 DOI: 10.1016/j.jot.2022.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 05/04/2022] [Accepted: 05/16/2022] [Indexed: 10/31/2022] Open
Abstract
Background/Objective The optimal surgical technique for the treatment of cervical degenerative disc disease (CDDD) towards decreasing the risk of adjacent segment disease (ASD) remains elusive. This study aimed to comparatively investigate the biomechanics of the lower cervical spine following fusion (ACDF) and artificial disc arthroplasty (Bryan® and Prestige LP®) using a validated geometrically patient-specific poroelastic finite element modeling (FEM) approach. Methods Ten subject-specific pre-operative models were developed and validated based on a FEM approach. Poroelastic models were then constructed using post-operation images for three different treatment scenarios: ACDF; Prestige LP® and Bryan® artificial discs at the C5-C6 level. The biomechanical responses at both surgical and adjacent spinal levels were studied subject to static and cyclic loading. Results Postoperatively, greater range of motion (ROM), higher annulus fibrosus stress and strain values, and increased disc height and fluid loss at the adjacent levels were detected post ACDF, as compared with pre-op as well as artificial disc arthroplasty. The facet joint forces were larger for the Prestige LP® disc, particularly during extension. The lowest values in disc height and fluid exchange were observed in the Bryan® artificial disc arthroplasty models. Conclusion Biomechanical analyses revealed that ACDF poses the highest potential risk for adjacent disc degeneration. The artificial discs investigated here (Prestige LP® and Bryan®) not only preserved motion at the instrumented level, but also sustained the pre-op ROM and decreased the intradiscal pressure (IDP) and facet joint forces (FJFs) at adjacent levels, particularly during flexion/extension. The Bryan® artificial disc demonstrated the most efficacy in maintaining the natural poroelastic characteristics of adjacent discs. The translational potential of this article This study provided a technique for clinicians to use quantitative data towards subject-specific evaluation to comparatively evaluate the impact of ACDF and disc arthroplasty using two types of artificial discs on the biomechanics of the cervical spine. It confirms differences in the poroelastic characteristics of adjacent discs for different fixation techniques, and reveals the advantage of artificial discs with a flexible core for decreasing the risk of ASD.
Collapse
Affiliation(s)
- Kinda Khalaf
- Department of Biomedical Engineering, Khalifa University of Science and Technology, And Health Engineering Innovation Center, Abu Dhabi, United Arab Emirates
| | - Mohammad Nikkhoo
- Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
| |
Collapse
|
5
|
Lu X, Zou F, Lu F, Ma X, Xia X, Jiang J. How to reconstruct the lordosis of cervical spine in patients with Hirayama disease? A finite element analysis of biomechanical changes focusing on adjacent segments after anterior cervical discectomy and fusion. J Orthop Surg Res 2022; 17:101. [PMID: 35172873 PMCID: PMC8848958 DOI: 10.1186/s13018-022-02984-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 02/02/2022] [Indexed: 02/08/2023] Open
Abstract
Purpose To compare the biomechanical changes of adjacent segments between patients with Hirayama disease and non-pathological people after anterior cervical discectomy and fusion (ACDF) operation, and to explore the optimal degree of local lordosis reconstruction during surgery. Methods A young male volunteer was recruited to establish a three-dimensional finite element model of the lower cervical spine based on the CT data. By adjusting the bony structures and simulating the operation process, the models of non-pathological individuals before and after ACDF, patients with Hirayama disease before and after ACDF, and different local lordosis angles were established. Then, the postoperative range of motion (RoM) and stress of the adjacent segments under flexion, extension, left bending, right bending, left rotation and right rotation were recorded and compared. Results The RoM and stress of all segments of lower cervical spine in patients with Hirayama disease are higher than those in non-pathological individual, and this trend still exists after ACDF surgery. When the local lordosis angle is under physiological conditions, the RoM and stress of the adjacent segments are minimum. Conclusion Compared with non-pathological people, Hirayama disease patients have differences in cervical biomechanics, which may lead to cervical hypermobility and overload. After ACDF, the possibility of adjacent segments degeneration is greater than that of non-pathological people. When the operation maintains the physiological local lordosis angle, it can slow down the degeneration.
Collapse
Affiliation(s)
- Xiao Lu
- Department of Orthopedics, Huashan Hospital, Fudan University, No. 12, Middle Wulumuqi Road, Jing'an District, Shanghai, 200040, China
| | - Fei Zou
- Department of Orthopedics, Huashan Hospital, Fudan University, No. 12, Middle Wulumuqi Road, Jing'an District, Shanghai, 200040, China
| | - Feizhou Lu
- Department of Orthopedics, Huashan Hospital, Fudan University, No. 12, Middle Wulumuqi Road, Jing'an District, Shanghai, 200040, China
| | - Xiaosheng Ma
- Department of Orthopedics, Huashan Hospital, Fudan University, No. 12, Middle Wulumuqi Road, Jing'an District, Shanghai, 200040, China
| | - Xinlei Xia
- Department of Orthopedics, Huashan Hospital, Fudan University, No. 12, Middle Wulumuqi Road, Jing'an District, Shanghai, 200040, China
| | - Jianyuan Jiang
- Department of Orthopedics, Huashan Hospital, Fudan University, No. 12, Middle Wulumuqi Road, Jing'an District, Shanghai, 200040, China.
| |
Collapse
|
6
|
Mumtaz M, Zafarparandeh I, Erbulut DU. Investigation into Cervical Spine Biomechanics Following Single, Multilevel and Hybrid Disc Replacement Surgery with Dynamic Cervical Implant and Fusion: A Finite Element Study. Bioengineering (Basel) 2022; 9:bioengineering9010016. [PMID: 35049725 PMCID: PMC8773264 DOI: 10.3390/bioengineering9010016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 12/23/2021] [Accepted: 12/29/2021] [Indexed: 11/30/2022] Open
Abstract
Cervical fusion has been a standard procedure for treating abnormalities associated with the cervical spine. However, the reliability of anterior cervical discectomy and fusion (ACDF) has become arguable due to its adverse effects on the biomechanics of adjacent segments. One of the drawbacks associated with ACDF is adjacent segment degeneration (ASD), which has served as the base for the development of dynamic stabilization systems (DSS) and total disc replacement (TDR) devices for cervical spine. However, the hybrid surgical technique has also gained popularity recently, but its effect on the biomechanics of cervical spine is not well researched. Thus, the objective of this FE study was to draw a comparison among single-level, bi-level, and hybrid surgery with dynamic cervical implants (DCIs) with traditional fusion. Reductions in the range of motion (ROM) for all the implanted models were observed for all the motions except extension, compared to for the intact model. The maximum increase in the ROM of 42% was observed at segments C5–C6 in the hybrid DCI model. The maximum increase in the adjacent segment’s ROM of 8.7% was observed in the multilevel fusion model. The maximum von Mises stress in the implant was highest for the multilevel DCI model. Our study also showed that the shape of the DCI permitted flexion/extension relatively more compared to lateral bending and axial rotation.
Collapse
Affiliation(s)
- Muzammil Mumtaz
- Engineering Center for Orthopaedic Research Excellence (ECORE), Departments of Bioengineering and Orthopaedic Surgery, Colleges of Engineering and Medicine, The University of Toledo, Toledo, OH 43606, USA;
| | - Iman Zafarparandeh
- Department of Biomedical Engineering, Medipol University, Istanbul 34810, Turkey;
| | - Deniz Ufuk Erbulut
- Herston Biofabrication Institute, Metro North Hospital and Health Service, Brisbane, QLD 4029, Australia
- Correspondence:
| |
Collapse
|
7
|
Wo J, Lv Z, Wang J, Shen K, Zhu H, Liu Y, Huang Y, Sun G, Li Z. Biomechanical Analysis of Cervical Artificial Disc Replacement Using Cervical Subtotal Discectomy Prosthesis. Front Bioeng Biotechnol 2021; 9:680769. [PMID: 34336799 PMCID: PMC8317600 DOI: 10.3389/fbioe.2021.680769] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 06/11/2021] [Indexed: 01/22/2023] Open
Abstract
Background: Anterior cervical discectomy and fusion (ACDF) sacrifices segmental mobility, which can lead to the acceleration of adjacent segment degeneration. The challenge has promoted cervical artificial disc replacement (CADR) as a substitute for ACDF. However, CADR has revealed a series of new issues that are not found in ACDF, such as hypermobility, subsidence, and wear phenomenon. This study designed a cervical subtotal discectomy prosthesis (CSDP) consisting of a cervical disc prosthesis structure (CDP structure), cervical vertebra fixation structure (CVF structure), link structure, and locking screw, aiming to facilitate motion control and reduce subsidence. The aim of this study was to assess the biomechanics of the CSDP using finite element (FE) analysis, friction-wear test, and non-human primates implantation study. Study Design: For the FE analysis, based on an intact FE C2-C7 spinal model, a CSDP was implanted at C5-C6 to establish the CSDP FE model and compare it with the Prestige LP prosthesis (Medtronic Sofamor Danek, Minneapolis, MN, United States). The range of motion (ROM), bone-implant interface stress, and facet joint force were calculated under flexion extension, lateral bending, and axial rotation. In addition, CSDP was elevated 1 mm to mimic an improper implantation technique to analyze the biomechanics of CSDP errors in the FE model. Moreover, the friction-wear test was conducted in vitro to research CSDP durability and observe surface wear morphology and total wear volume. Finally, the CSDP was implanted into non-human primates, and its properties were evaluated and verified by radiology. Results: In the FE analysis, the ROM of the CSDP FE model was close to that of the intact FE model in the operative and adjacent segments. In the operative segment, the CSDP error FE model increased ROM in flexion extension, lateral bending, and axial rotation. The maximum stress in the CSDP FE model was similar to that of the intact FE model and was located in the peripheral cortical bone region. The facet joint force changes were minimal in extension, lateral bending, and axial rotation loads in CSDP. In the friction-wear test, after the 150-W movement simulation, both the CVF-link-junction and the CDP-link-junction had slight wear. In the CSDP non-human primate implantation study, no subsidence, dislocation, or loosening was observed. Conclusion: In the FE analysis, the biomechanical parameters of the CSDP FE model were relatively close to those of the intact FE model when compared with the Prestige LP FE model. In terms of CSDP error FE models, we demonstrated that the implantation position influences CSDP performance, such as ROM, bone-implant interface stress, and facet joint force. In addition, we performed a friction-wear test on the CSDP to prove its durability. Finally, CSDP studies with non-human primates have shown that the CSDP is effective.
Collapse
Affiliation(s)
- Jin Wo
- Department of Orthopedics, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Zhenjing Lv
- Department of Spine Orthopedics, Guangdong Hospital of Integrated Traditional Chinese and Western Medicine, Foshan, China
| | - Jing Wang
- Department of Neurosurgery, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Kui Shen
- Department of Orthopedics, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Haoran Zhu
- Department of Orthopedics, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Yang Liu
- Department of Orthopedics, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Yuen Huang
- Department of Rehabilitation, First Affiliated Hospital, Jinan University, Guangzhou, China
| | - Guodong Sun
- Department of Orthopedics, First Affiliated Hospital, Jinan University, Guangzhou, China.,Department of Orthopedics, Fifth Affiliated Hospital, Heyuan Shenhe People's Hospital, Jinan University, Heyuan, China
| | - Zhizhong Li
- Department of Orthopedics, First Affiliated Hospital, Jinan University, Guangzhou, China.,Department of Orthopedics, Fifth Affiliated Hospital, Heyuan Shenhe People's Hospital, Jinan University, Heyuan, China.,Department of Orthopedics, Heyuan People's Hospital, Heyuan Affiliated Hospital of Jinan University, Heyuan, China
| |
Collapse
|
8
|
Yoganandan N, Purushothaman Y, Choi H, Baisden J, Rajasekaran D, Banerjee A, Jebaseelan D, Kurpad S. Biomechanical Study of Cervical Disc Arthroplasty Devices Using Finite Element Modeling. JOURNAL OF ENGINEERING AND SCIENCE IN MEDICAL DIAGNOSTICS AND THERAPY 2021; 4:021004. [PMID: 35832636 PMCID: PMC8597568 DOI: 10.1115/1.4049907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 01/11/2021] [Indexed: 06/15/2023]
Abstract
Many artificial discs for have been introduced to overcome the disadvantages of conventional anterior discectomy and fusion. The purpose of this study was to evaluate the performance of different U.S. Food and Drug Administration (FDA)-approved cervical disc arthroplasty (CDA) on the range of motion (ROM), intradiscal pressure, and facet force variables under physiological loading. A validated three-dimensional finite element model of the human intact cervical spine (C2-T1) was used. The intact spine was modified to simulate CDAs at C5-C6. Hybrid loading with a follower load of 75 N and moments under flexion, extension, and lateral bending of 2 N·m each were applied to intact and CDA spines. From this work, it was found that at the index level, all CDAs except the Bryan disc increased ROM, and at the adjacent levels, motion decreased in all modes. The largest increase occurred under the lateral bending mode. The Bryan disc had compensatory motion increases at the adjacent levels. Intradiscal pressure reduced at the adjacent levels with Mobi-C and Secure-C. Facet force increased at the index level in all CDAs, with the highest force with the Mobi-C. The force generally decreased at the adjacent levels, except for the Bryan disc and Prestige LP in lateral bending. This study demonstrates the influence of different CDA designs on the anterior and posterior loading patterns at the index and adjacent levels with head supported mass type loadings. The study validates key clinical observations: CDA procedure is contraindicated in cases of facet arthroplasty and may be protective against adjacent segment degeneration.
Collapse
Affiliation(s)
- Narayan Yoganandan
- Center for NeuroTrauma Research, Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI 53226; VA Medical Center, Medical College of Wisconsin, Milwaukee, WI 53226; Department of Neurosurgery, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226
| | - Yuvaraj Purushothaman
- Center for NeuroTrauma Research, Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Hoon Choi
- Center for NeuroTrauma Research, Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Jamie Baisden
- Center for NeuroTrauma Research, Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Deepak Rajasekaran
- Center for NeuroTrauma Research, Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Anjishnu Banerjee
- Division of Biostatistics, Medical College of Wisconsin, Milwaukee, WI 53226
| | - Davidson Jebaseelan
- School of Mechanical Engineering, Vellore Institute of Technology, Chennai Campus, Chennai 600036, India
| | - Shekar Kurpad
- Center for NeuroTrauma Research, Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI 53226; VA Medical Center, Medical College of Wisconsin, Milwaukee, WI 53226
| |
Collapse
|
9
|
Hui N, Phan K, Lee MY, Kerferd J, Singh T, Mobbs RJ. The Changes in Cervical Biomechanics After CTDR and Its Association With Heterotopic Ossification: A Systematic Review and Meta-analysis. Global Spine J 2021; 11:565-574. [PMID: 32677512 PMCID: PMC8119929 DOI: 10.1177/2192568220922949] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
STUDY DESIGN A systematic review and meta-analysis. OBJECTIVES Cervical total disc replacement (CTDR) can preserve range of motion (ROM) of the operated spinal segment in cadaver studies. Evidence is less clear in clinical trials. The present study aims to investigate the differences in cervical biomechanics before and after CTDR and its association with heterotopic ossification (HO) development. METHOD Articles that reported the rate of HO and ≥1 difference in cervical biomechanics were included in quantitative analyses. We pooled the mean difference (MD) of cervical biomechanics before and after CTDR. Subgroup analyses and metaregression analyses were conducted to identify potential contributors to heterogeneity. RESULTS Of the 599 studies screened, 35 studies were included in the final analysis. In comparison with preoperative values, ROM of the spinal segment inferior (MD: 0.38; 95% CI: 0.02 to 0.74) and superior (MD: 0.43; 95% CI: 0.12 to 0.75) to the surgical spinal segment, functional spinal unit (FSU) angle (MD: 2.23; 95% CI: 1.11 to 3.35), and C2/C7 Cobb angle (MD: 3.49; 95% CI: 1.73 to 5.25) significantly increased after CTDR. In contrast, FSU and cervical ROM at baseline were no different from follow-up. On multivariable meta-regression analyses, HO and ROM-limiting HO were not associated with changes in cervical biomechanics. Single-level CTDR and duration of follow-up were associated with changes in cervical biomechanics. CONCLUSION Our study reported the pooled mean of biomechanics at baseline and final follow-up and their differences. The changes in biomechanics were not associated with the rates of HO and ROM-limiting HO.
Collapse
Affiliation(s)
- Nicholas Hui
- NeuroSpine Surgery Research Group, Sydney, Australia,7800University of New South
Wales, Sydney, Australia
| | - Kevin Phan
- NeuroSpine Surgery Research Group, Sydney, Australia,7800University of New South
Wales, Sydney, Australia
| | - Mei-Yi Lee
- NeuroSpine Surgery Research Group, Sydney, Australia,85120Hong Kong Polytechnic
University, Hong Kong
| | - Jack Kerferd
- NeuroSpine Surgery Research Group, Sydney, Australia,7800University of New South
Wales, Sydney, Australia
| | - Telvinderjit Singh
- NeuroSpine Surgery Research Group, Sydney, Australia,7800University of New South
Wales, Sydney, Australia
| | - Ralph J. Mobbs
- NeuroSpine Surgery Research Group, Sydney, Australia,7800University of New South
Wales, Sydney, Australia,NeuroSpineClinic, Sydney, Australia,Ralph J. Mobbs, NeuroSpineClinic, Suite 7,
Level 7, Prince of Wales Private Hospital, Randwick, New South Wales 2031,
Australia.
| |
Collapse
|
10
|
Houten JK, Kinon MD, Weinstein GR. 4-Point C2 Fixation for Occipitocervical Fusion: Technical Case Report. World Neurosurg 2021; 148:38-43. [PMID: 33422720 DOI: 10.1016/j.wneu.2020.12.159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/28/2020] [Accepted: 12/29/2020] [Indexed: 12/27/2022]
Abstract
BACKGROUND Occipitocervical fusion is an important surgical procedure to treat instability of the upper cervical and craniocervical junction. Fixation to the dense cortical bone of the occiput, contemporaneously typically accomplished with a plate and screws, is known to be strong and durable, but there are many competing methods used to secure an adequate number of fixation points of sufficient strength at the cervical end. Extension of hardware to the midcervical region to acquire additional fixation points, however, results in loss of subaxial motion segments and additional potential morbidity. The C2 vertebra is unique in that its morphology and dimensions permit fixation with longer screws than are typically possible to place in the midcervical lateral masses. Translaminar and pars screw techniques, both commonly used to achieve C2 fixation, are not mutually exclusive, as their respective trajectories are considerably different and engage different portions of the bony anatomy. METHODS We describe a novel, 4-point C2 fixation technique for OC fusion that may avoid the need to extend fusion to the subaxial spine. RESULTS This technical note illustrates how 4-point C2 fixation can be employed in occiptocervical fusion. CONCLUSIONS 4-point fixation of C2 combining translaminar and pars screw placement is technically feasible and may be a suitable strategy to spare subaxial motion segments in OC fusion procedures. Futher investigation may establish its applicability to additional surgical procedures.
Collapse
Affiliation(s)
- John K Houten
- Department of Surgery, Maimonides Medical Center, Brooklyn, New York, USA; Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, New York, USA.
| | - Merritt D Kinon
- Department of Neurological Surgery, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, USA
| | - Gila R Weinstein
- Department of Surgery, Maimonides Medical Center, Brooklyn, New York, USA
| |
Collapse
|
11
|
Unal TC, Aktoklu M, Gel MS, Dolen D, Dolas I. Spontaneous fusion several years after undiagnosed cervical distractive flexion injury: a report of 3 cases. Br J Neurosurg 2020:1-3. [PMID: 32436447 DOI: 10.1080/02688697.2020.1767283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
We report three cases of spontaneously fused distractive flexion injury (DFI) in the cervical spine detected several years after the trauma. This is the first report in the literature that describes such late presentation of healed DFI. Although injuries are considered highly unstable requiring fusion surgery, all three healed spontaneously without intervention or immobilization. Despite significant misalignment, stability was confirmed with flexion-extension radiographs. All the three patients had no neurologic deficits. The possibility of healed old DFI should be kept in mind for patients who present with neck pain and a history of high-energy trauma.
Collapse
Affiliation(s)
- Tugrul Cem Unal
- Department of Neurosurgery, Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Mehmet Aktoklu
- Department of Neurosurgery, Tunceli State Hospital, Tunceli, Turkey
| | - Mehmet Selim Gel
- Department of Neurosurgery, Kanuni Training and Research Hospital, Trabzon, Turkey
| | - Duygu Dolen
- Department of Neurosurgery, Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Ilyas Dolas
- Department of Neurosurgery, Faculty of Medicine, Istanbul University, Istanbul, Turkey
| |
Collapse
|
12
|
Hui N, Phan K, Cheng HMK, Lin YH, Mobbs RJ. Complications of cervical total disc replacement and their associations with heterotopic ossification: a systematic review and meta-analysis. 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 2020; 29:2688-2700. [DOI: 10.1007/s00586-020-06400-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 03/14/2020] [Accepted: 03/27/2020] [Indexed: 12/23/2022]
|
13
|
Hui N, Phan K, Kerferd J, Lee M, Mobbs RJ. Comparison of M6-C and Mobi-C cervical total disc replacement for cervical degenerative disc disease in adults. JOURNAL OF SPINE SURGERY 2019; 5:393-403. [PMID: 32042989 DOI: 10.21037/jss.2019.09.27] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Background Cervical total disc replacement (CTDR) is complicated by adjacent segment degeneration (ASD). Since non-physiological spine kinematics after CTDR was postulated to cause ASD, M6-C prosthesis has been developed to better replicate the natural kinematics of the intervertebral disc. This retrospective cohort study aims to compare the short-term outcomes between patients receiving either the M6-C or Mobi-C prostheses. Methods Patients who had refractory radiculopathy and/or myelopathy secondary to cervical degenerative disc disease and underwent CTDR between March 2004 and April 2017 were included. All CTDRs were performed by a single surgeon at a single institution. Self-reported clinical outcomes and radiological parameters were evaluated at baseline and final follow-up between March 2004 and April 2018. Results Sixty-two patients with greater than 1-year follow-up or who developed HO within 12 months of surgery, were included in the study. The mean radiological follow-up was 29.0 months (3-84 months), which includes 7 patients with less than 12 months follow-up who also developed HO. The changes in clinical and radiological measures were comparable between M6-C and Mobi-C prostheses. Thirty-seven out of 52 spinal segments (71.2%) and 10 out of 16 spinal segments (62.5%) developed HO in M6-C and Mobi-C group respectively. There was no significant difference in the rate of HO between the two groups. Conclusions No short-term differences were found in clinical or radiological outcomes between patients who received either the M6-C or Mobi-C prosthesis. Further randomized trials with a long-term follow-up period are warranted to determine the safety and efficacy of M6-C prosthesis.
Collapse
Affiliation(s)
- Nicholas Hui
- NeuroSpine Surgery Research Group (NSURG), The University of New South Wales, Sydney, NSW, Australia
| | - Kevin Phan
- NeuroSpine Surgery Research Group (NSURG), The University of New South Wales, Sydney, NSW, Australia
| | - Jack Kerferd
- NeuroSpine Surgery Research Group (NSURG), The University of New South Wales, Sydney, NSW, Australia
| | - Meiyi Lee
- NeuroSpine Surgery Research Group (NSURG), The University of New South Wales, Sydney, NSW, Australia
| | - Ralph J Mobbs
- NeuroSpine Surgery Research Group (NSURG), The University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
14
|
Choi H, Purushothaman Y, Baisden J, Yoganandan N. Unique biomechanical signatures of Bryan, Prodisc C, and Prestige LP cervical disc replacements: a finite element modelling study. 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 2019; 29:2631-2639. [DOI: 10.1007/s00586-019-06113-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 07/26/2019] [Accepted: 08/12/2019] [Indexed: 12/13/2022]
|
15
|
Li Y, Shen H, Khan KZ, Fang S, Liao Z, Liu W. Comparison of Multilevel Cervical Disc Replacement and Multilevel Anterior Discectomy and Fusion: A Systematic Review of Biomechanical and Clinical Evidence. World Neurosurg 2018; 116:94-104. [PMID: 29753897 DOI: 10.1016/j.wneu.2018.05.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 04/30/2018] [Accepted: 05/02/2018] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The aim of this study was to comprehensively compare the clinical and biomechanical efficiency of anterior cervical discectomy and fusion (ACDF) with anterior cervical disc replacement (ACDR) for treatment of multilevel cervical disc disease using a meta-analysis and systematical review. METHODS A literature search was performed using PubMed, MEDLINE, EMBASE, and the Cochrane Library for articles published between January 1960 and December 2017. Both clinical and biomechanical parameters were analyzed. Statistical tests were conducted by Revman 5.3. Nineteen studies including 10 clinical studies and 9 biomechanical studies were filtered out. RESULTS The pooled results for clinical efficiency showed that no significant difference was observed in blood loss (P = 0.09; mean difference [MD], 7.38; confidence interval [CI], -1.16 to 15.91), hospital stay (P = 0.33; MD, -0.25; CI, -0.76 to 0.26), Japanese Orthopaedic Association scores (P = 0.63; MD, -0.11; CI, -0.57 to 0.34), visual analog scale (P = 0.08; MD, -0.50; CI, -1.06 to 0.05), and Neck Disability Index (P = 0.33; MD, -0.55; CI, -1.65 to 0.56) between the 2 groups. Compared with ACDF, ACDR did show increased surgical time (P = 0.03; MD, 31.42; CI, 2.71-60.14). On the other hand, ACDR showed increased index range of motion (ROM) (P < 0.00001; MD, 13.83; CI, 9.28-18.39), lower rates of adjacent segment disease (ASD) (P = 0.001; odds ratio [OR], 0.27; CI, 0.13-0.59), complications (P = 0.006; OR, 0.62; CI, 0.45-0.87), and rate of subsequent surgery (P < 0.00001; OR, 0.25; CI, 0.14-0.44). As for biomechanical performance, ACDR maintained index ROM and avoided compensation in adjacent ROM and tissue pressure. CONCLUSIONS Multilevel ACDR may be an effective and safe alternative to ACDF in terms of clinical and biomechanical performance. However, further multicenter and prospective studies should be conducted to obtain a stronger and more reliable conclusion.
Collapse
Affiliation(s)
- Yang Li
- State Key Laboratory of Tribology, Tsinghua University, Beijing, China and Department of Mechanical Engineering, Tsinghua University, Beijing, China
| | - Hangkai Shen
- State Key Laboratory of Tribology, Tsinghua University, Beijing, China and Department of Mechanical Engineering, Tsinghua University, Beijing, China
| | - Kamran Z Khan
- Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Shushu Fang
- School of Pharmacy, Peking University, Beijing, China
| | - Zhenhua Liao
- Biomechanics and Biotechnology Laboratory, Research Institute of Tsinghua University in Shenzhen, Shenzhen, People's Republic of China
| | - Weiqiang Liu
- Department of Mechanical Engineering, Tsinghua University, Beijing, People's Republic of China and Biomechanics and Biotechnology Laboratory, Research Institute of Tsinghua University in Shenzhen, Shenzhen, People's Republic of China.
| |
Collapse
|
16
|
Wang LN, Hu BW, Wang L, Song YM, Yang X, Liu LM, Liu H. Clinical and radiographic outcome of dynamic cervical implant (DCI) arthroplasty for degenerative cervical disc disease: a minimal five-year follow-up. BMC Musculoskelet Disord 2018; 19:101. [PMID: 29615017 PMCID: PMC5883531 DOI: 10.1186/s12891-018-2017-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 03/22/2018] [Indexed: 02/05/2023] Open
Abstract
Background To evaluate the mid- to long-term clinical and radiographic outcomes of anterior cervical discectomy and dynamic cervical implant (DCI) arthroplasty for degenerative cervical disc disease. Methods From April 2010 to October 2010, 38 patients with single- or double-level cervical disc herniation underwent anterior cervical discectomy and DCI arthroplasty. The clinical results and radiographic outcomes of these 38 patients (42 levels) were retrospectively evaluated. The clinical results included the visual analogue scale, Japanese Orthopaedic Association score, Neck Disability Index score, 36-item short form health survey questionnaire, and incidences of complications and neurological deterioration. Radiographic results including cervical alignment, intervertebral height, cervical range of motion (ROM), ROM of the functional spinal unit, adjacent intervertebral ROM, migration, subsidence, and heterotopic ossification (HO) were assessed on plain radiography, three-dimensional computed tomography, and magnetic resonance imaging. Results The mean follow-up period was 72.3 months (range 68–78 months). During follow-up, all patients showed significant improvements in the visual analogue scale score, Japanese Orthopaedic Association score, Neck Disability Index score, 36-item short form health survey physical component summary score and mental component summary score. The ROM of the functional spinal unit was partly reduced. The DCI migrated forward in 10 of 42 (23.8%) cases, and HO was detected in 24 of the 42 (57.1%) DCI segments. Subsidence was observed in 14 of 42 (33.3%) DCI segments. Two patients experienced symptom recurrence, and were treated conservatively. Conclusions The clinical efficacy of DCI arthroplasty was maintained during mid- to long-term follow-up. HO formation is a common phenomenon, leading to a substantial decrease in ROM at the index level and recurrence of neurological symptoms. The incidence of implant subsidence and migration is relatively high, leaving a potential risk of symptoms at the index level and adjacent segment degeneration. We consider that the first choice for patients with degenerative cervical disc disease should still be total disc replacement or anterior cervical discectomy and fusion, rather than DCI arthroplasty.
Collapse
Affiliation(s)
- Lin-Nan Wang
- Department of Orthopedics, West China Hospital, Sichuan University, 37 Guoxue Rd, Chengdu, 610041, China
| | - Bo-Wen Hu
- Department of Orthopedics, West China Hospital, Sichuan University, 37 Guoxue Rd, Chengdu, 610041, China
| | - Lei Wang
- Department of Orthopedics, West China Hospital, Sichuan University, 37 Guoxue Rd, Chengdu, 610041, China.
| | - Yue-Ming Song
- Department of Orthopedics, West China Hospital, Sichuan University, 37 Guoxue Rd, Chengdu, 610041, China.
| | - Xi Yang
- Department of Orthopedics, West China Hospital, Sichuan University, 37 Guoxue Rd, Chengdu, 610041, China
| | - Li-Min Liu
- Department of Orthopedics, West China Hospital, Sichuan University, 37 Guoxue Rd, Chengdu, 610041, China
| | - Hao Liu
- Department of Orthopedics, West China Hospital, Sichuan University, 37 Guoxue Rd, Chengdu, 610041, China
| |
Collapse
|
17
|
Zhuang Y, Cai G, Fu C, Zhang W, Zhao W, Wang R, Wang C, Shi S, Chen C. Novel combination of paraspinal keyhole surgery with a tubular retractor system leads to significant improvements in lumbar intraspinal extramedullary schwannomas. Oncol Lett 2017; 14:7873-7879. [PMID: 29344232 PMCID: PMC5755262 DOI: 10.3892/ol.2017.7203] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 06/02/2017] [Indexed: 12/27/2022] Open
Abstract
The aim of the present study was to investigate the efficacy of combining paraspinal keyhole surgery with a tubular retractor system for the microsurgical removal of lumbar intraspinal extramedullary schwannomas. A retrospective analysis was conducted of 56 patients with lumbar intraspinal extramedullary schwannomas who were treated using the microsurgical paraspinal keyhole approach with a tubular retractor system. The mean ± standard deviation was calculated for the following parameters: Surgery time (96.21±14.64 min), hemorrhagic volume (28.54±9.72 ml), bed rest (2.55±0.5 days) and hospital stay (5.68±0.72 days). Two patients presented with cerebrospinal fluid leakage and one patient exhibited a nerve root injury. At a 6-month follow-up visit, postoperative Japanese Orthopedic Association (JOA) and visual analog scale (VAS) scores were evaluated. The mean ± standard deviation JOA scores were 12.00±2.07 for preoperative, 14.73±2.05 for 1 week postoperative, 20.07±2.32 for 3 months postoperative and 21.75±2.18 for 6 months postoperative. The improvement rate was 16.07, 47.48 and 59.77%, respectively. The mean ± standard deviation VAS scores were 6.64±1.31 for preoperative, 3.82±1.51 for 1 week postoperative, 2.11±1.17 for 3 months postoperative and 1.50±1.51 for 6 months postoperative. The JOA and VAS scores improved significantly (P<0.05). Magnetic resonance imaging and computed tomography were performed preoperatively, immediately following surgery and at the 6-month postoperative visit to confirm the efficacy of the resections and evaluate spinal stability. No residual tumors were identified at follow-up. No alterations in the stability of the spine were observed postoperatively. The combination of the microsurgical paraspinal keyhole approach with the tubular retractor system was successful in treating lumbar intraspinal extramedullary schwannomas. The surgical approach was associated with decreased hemorrhages, decreased duration of hospital stay, faster recovery and improved postoperative maintenance of spinal stability.
Collapse
Affiliation(s)
- Yuandong Zhuang
- Department of Neurosurgery, Union Hospital of Fujian Medical University, Fujian Institute of Neurosurgery, Fuzhou, Fujian 350001, P.R. China
| | - Gangfeng Cai
- Department of Neurosurgery, Union Hospital of Fujian Medical University, Fujian Institute of Neurosurgery, Fuzhou, Fujian 350001, P.R. China
| | - Chaofeng Fu
- Department of Neurosurgery, Union Hospital of Fujian Medical University, Fujian Institute of Neurosurgery, Fuzhou, Fujian 350001, P.R. China
| | - Weiqiang Zhang
- Department of Neurosurgery, Union Hospital of Fujian Medical University, Fujian Institute of Neurosurgery, Fuzhou, Fujian 350001, P.R. China
| | - Wei Zhao
- Department of Neurosurgery, Union Hospital of Fujian Medical University, Fujian Institute of Neurosurgery, Fuzhou, Fujian 350001, P.R. China
| | - Rui Wang
- Department of Neurosurgery, Union Hospital of Fujian Medical University, Fujian Institute of Neurosurgery, Fuzhou, Fujian 350001, P.R. China
| | - Chunhua Wang
- Department of Neurosurgery, Union Hospital of Fujian Medical University, Fujian Institute of Neurosurgery, Fuzhou, Fujian 350001, P.R. China
| | - Songsheng Shi
- Department of Neurosurgery, Union Hospital of Fujian Medical University, Fujian Institute of Neurosurgery, Fuzhou, Fujian 350001, P.R. China
| | - Chunmei Chen
- Department of Neurosurgery, Union Hospital of Fujian Medical University, Fujian Institute of Neurosurgery, Fuzhou, Fujian 350001, P.R. China
| |
Collapse
|
18
|
Biomechanical Analysis of Two-level Cervical Disc Replacement With a Stand-alone U-shaped Disc Implant. Spine (Phila Pa 1976) 2017; 42:E1173-E1181. [PMID: 28198781 DOI: 10.1097/brs.0000000000002128] [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] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Biomechanical study using a three-dimensional nonlinear finite element model. OBJECTIVE To analyze biomechanical changes with three prostheses based on two-level arthroplasty and to verify the biomechanical efficiency of dynamic cervical implants (DCIs) with a stand-alone U-shaped structure. SUMMARY OF BACKGROUND DATA Few studies have compared biomechanical behavior of various prostheses as they relate with clinical results after two-level total disc replacement. METHODS Three arthroplasty devices Mobi-C, porous coated motion (PCM), and DCI were inserted at the C4-C6 disc space and analyzed. Displacement loading was applied to the center of the endplate at the C3 level to simulate flexion and extension motions. RESULTS The motion distributions in extension with DCI and in flexion with DCI and Mobi-C were relatively close to that in the intact model. Mobi-C and PCM obviously increased the combined extension range of motion at the index levels, but both resulted in about 45% decrease in extension moment. DCI showed a trend in strain energy similar to that of healthy discs. PCM exhibited a facet joint stress distribution almost similar to that of the intact model. DCI did not generate significant overloading at cartilage between the index levels, whereas the maximum facet joint stress increased with Mobi-C was about 39%. The maximum stress on a ultrahigh molecular-weight-polyethylene core was above the yield stress (42.43 MPa for Mobi-C and 30.94 MPa for PCM). CONCLUSION Each prosthesis shows its biomechanical advantages and disadvantages. However, DCI has the capacity to preserve motion and store energy under external loading, similar to the behavior of normal discs. Compared with Mobi-C, both DCI and PCM showed a lower stress at cartilage between index levels, which may avoid facet joint degeneration to some extent. Such a well-controlled arthroplasty device with a stand-alone structure may be a potential candidate and needs to be investigated in future studies. LEVEL OF EVIDENCE 5.
Collapse
|
19
|
Li Y, Zhang Z, Liao Z, Mo Z, Liu W. Finite Element Analysis of Influence of Axial Position of Center of Rotation of a Cervical Total Disc Replacement on Biomechanical Parameters: Simulated 2-Level Replacement Based on a Validated Model. World Neurosurg 2017; 106:932-938. [DOI: 10.1016/j.wneu.2017.07.079] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 07/13/2017] [Accepted: 07/14/2017] [Indexed: 11/26/2022]
|
20
|
Cervical Disk Replacement With Discover Versus Fusion in a Single-Level Cervical Disk Disease: A Prospective Single-Center Randomized Trial With a Minimum 2-Year Follow-up. Clin Spine Surg 2017; 30:E515-E522. [PMID: 28525471 DOI: 10.1097/bsd.0000000000000170] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
STUDY DESIGN Prospective randomized study. OBJECTIVE To compare the clinical outcome after Discover arthroplasty versus anterior cervical discectomy and fusion (ACDF) in patients treated for symptomatic single-level cervical disk disease. SUMMARY OF BACKGROUND DATA ACDF is still the gold standard for surgical treatment of cervical spine degenerative disk disease. However, results of many studies suggest that it may cause degenerative changes at levels immediately above and below the fusion, known as adjacent segment degenerative disease. Cervical arthroplasty has recently been introduced as an alternative to standard procedure of ACDF. It showed decreased surgical morbidity, decreased complications from postoperative immobilization, and an earlier return to previous level of function. MATERIALS AND METHODS A total of 105 consecutive patients with single-level cervical disk disease, producing radiculopathy and/or myelopathy were randomly divided into groups to undergo ACDF or Discover arthroplasty. All patients were evaluated with preoperative and postoperative serial radiographic studies and clinically, using Neck Disability Index, Visual Analog Scale and neurological status at 3, 6, 12, and 24 months. RESULTS The results of our study indicate that cervical arthroplasty using Discover Artificial Cervical Disc provides favorable clinical and radiologic outcomes in a follow-up period of 24 months. There has been significant improvement in clinical parameters, Visual Analog Scale and Neck Disability Index, at 3, 6, 12, and 24 months in arthroplasty group comparing to control group. CONCLUSION The Discover artificial cervical disc replacement offers favorable outcome compared with ACDF for a single-level cervical disk disease at short-term and long-term follow-up.
Collapse
|
21
|
Cervical facet force analysis after disc replacement versus fusion. Clin Biomech (Bristol, Avon) 2017; 44:52-58. [PMID: 28340364 DOI: 10.1016/j.clinbiomech.2017.03.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 01/31/2017] [Accepted: 03/16/2017] [Indexed: 02/07/2023]
Abstract
BACKGROUND Cervical total disc replacement was developed to preserve motion and reduce adjacent-level degeneration relative to fusion, yet concerns remain that total disc replacement will lead to altered facet joint loading and long-term facet joint arthrosis. This study is intended to evaluate changes in facet contact force, pressure and surface area at the treated and superior adjacent levels before and after discectomy, disc replacement, and fusion. METHODS Ten fresh-frozen human cadaveric cervical spines were potted from C2 to C7 with pressure sensors placed into the facet joints of C3-C4 and C4-C5 via slits in the facet capsules. Moments were applied to the specimens to produce axial rotation, lateral bending and extension. Facet contact force and pressure were measured at both levels for intact, discectomy at C4-C5, disc replacement with ProDisc-C (Synthes Spine, West Chester, Pennsylvania, USA) at C4-C5, and anterior discectomy and fusion with Cervical Spine Locking Plate (Synthes Spine, West Chester, Pennsylvania, USA) at C4-C5. Facet contact area was calculated from the force and pressure measurements. An analysis of variance was used to determine significant differences with P-values <0.05 indicating significance. FINDINGS Facet contact force was elevated at the treated level under extension following both discectomy and disc replacement, while facet contact pressure and area were relatively unchanged. Facet contact force and area were decreased at the treated level following fusion for all three loading conditions. INTERPRETATION Total disc replacement preserved facet contact force for all scenarios except extension at the treated level, highlighting the importance of the anterior disco-ligamentous complex. This could promote treated-level facet joint disease.
Collapse
|
22
|
卢 腾, 张 廷, 董 军, 臧 全, 杨 宝, 王 栋, 李 浩, 贺 西. [Impact of anterior cervical fusion surgeries on adjacent segments: a finite element analysis]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2017; 37:49-55. [PMID: 28109098 PMCID: PMC6765756 DOI: 10.3969/j.issn.1673-4254.2017.01.09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Indexed: 06/06/2023]
Abstract
OBJECTIVE To investigate the changes in the range of motion (ROM) and stress of the intervertebral disc and facet joint of the adjacent segments following anterior cervical corpectomy and fusion (ACCF) and anterior cervical discectomy and fusion (ACDF) using finite element analysis. METHODS A three-dimensional finite element model of the lower cervical vertebrae was constructed and validated by comparing the ROM of the finite element model against the published data. After the validation of successful modeling, finite element models of ACDF and ACCF were constructed. The ROM and the stress of the intervertebral disc and facet joint of the adjacent segments were compared between the intact lower cervical vertebrae and the cervical vertebrae after ACDF and ACCF. RESULTS The ROM of the finite element model was consistent with the published data. The total ROM and the ROM of the fusion segments with ACDF and ACCF were significantly decreased compared with the intact cervical vertebrae. In the adjacent segments following ACDF and ACCF, the ROM the adjacent segments and the stress peak of the intervertebral disc and facet joint all increased obviously compared with those of intact cervical vertebrae. CONCLUSION After fusion surgeries, the total ROM of the cervical vertebrae decreases and the ROM of the adjacent segment increases. The stress peak of the intervertebral disc and facet joint of the adjacent segments also increases to significantly alter the physiological characteristics of the intact cervical vertebrae.
Collapse
Affiliation(s)
- 腾 卢
- />西安交通大学第二附属医院脊柱外科,西安 陕西 710004Department of Spine Surgery, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
| | - 廷 张
- />西安交通大学第二附属医院脊柱外科,西安 陕西 710004Department of Spine Surgery, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
| | - 军 董
- />西安交通大学第二附属医院脊柱外科,西安 陕西 710004Department of Spine Surgery, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
| | - 全金 臧
- />西安交通大学第二附属医院脊柱外科,西安 陕西 710004Department of Spine Surgery, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
| | - 宝辉 杨
- />西安交通大学第二附属医院脊柱外科,西安 陕西 710004Department of Spine Surgery, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
| | - 栋 王
- />西安交通大学第二附属医院脊柱外科,西安 陕西 710004Department of Spine Surgery, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
| | - 浩鹏 李
- />西安交通大学第二附属医院脊柱外科,西安 陕西 710004Department of Spine Surgery, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
| | - 西京 贺
- />西安交通大学第二附属医院脊柱外科,西安 陕西 710004Department of Spine Surgery, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710004, China
| |
Collapse
|
23
|
Feasibility and Biomechanics of Multilevel Arthroplasty and Combined Cervical Arthrodesis and Arthroplasty. Clin Spine Surg 2016; 29:E522-E531. [PMID: 23698102 DOI: 10.1097/bsd.0b013e31829920f0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
STUDY DESIGN A new experimental protocol was applied utilizing a simplified postural control model. Multiple constructs were tested nondestructively by interconnecting segmental rods to screws. OBJECTIVE To investigate how posture and distribution of segmental angles under physiological loads are affected by combined cervical arthroplasty and fusion. SUMMARY OF BACKGROUND DATA Previous studies of biomechanics of multilevel arthroplasty have focused on range of motion and intradiscal pressure. No previous study has investigated postural changes and segmental angle distribution. METHODS In 7 human cadaveric C3-T1 specimens, C4-C5, C5-C6, and C6-C7 disks were replaced with ProDisc-C (Synthes). Combinations of fusion (f) adjacent to arthroplasty (A) were simulated at C4-C5, C5-C6, and C6-C7, respectively: fAA, AfA, AAf, ffA, fAf, Aff, fff. C3-C4 and C7-T1 remained intact. A compressive belt apparatus simulated normal muscle cocontraction and gravitational preload; C3-C4, C4-C5, C5-C6, C6-C7, and C7-T1 motions were tracked independently. Parameters studied were segmental postural compensation, neutral buckling, and shift in sagittal plane instantaneous axis of rotation (IAR). RESULTS With one or more levels unfused, the arthroplasty levels preferentially moved toward upright posture before the intact levels. Neutral buckling was greatest for 3-level arthroplasty, less for 2-level arthroplasty, and least for 1-level arthroplasty. Among the three 1-level arthroplasty groups (ffA, fAf, Aff), arthroplasty at the caudalmost level resulted in significantly greater buckling than with arthroplasty rostralmost or at mid-segment (P<0.04, analysis of variance/Holm-Sidak). Although IAR location was related to buckling, this correlation did not reach significance (P=0.112). CONCLUSIONS Arthroplasty levels provide the "path of least resistance," through which the initial motion is more likely to occur. The tendency for specimens to buckle under vertical compression became greater with more arthroplasty levels. Buckling appeared more severe with arthroplasty more caudal. Buckling only moderately correlated to shifts in IAR, meaning slight malpositioning of the devices would not necessarily cause buckling.
Collapse
|
24
|
Klessinger S. Interventional pain therapy in cervical post-surgery syndrome. World J Anesthesiol 2016; 5:38-43. [DOI: 10.5313/wja.v5.i2.38] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 05/31/2016] [Accepted: 07/13/2016] [Indexed: 02/07/2023] Open
Abstract
Fifteen percent to forty percent of patients present with persistent disabling neck pain or radicular pain after cervical spine surgery. Persistent pain after cervical surgery is called cervical post-surgery syndrome (CPSS). This review investigates the literature about interventional pain therapy for these patients. Because different interventions with different anatomical targets exist, it is important to find the possible pain source. There has to be a distinction between radicular symptoms (radicular pain or radiculopathy) or axial pain (neck pain) and between persistent pain and a new onset of pain after surgery. In the case of radicular symptoms, inadequate decompression or nerve root adherence because of perineural scarring are possible pain causes. Multiple structures in the cervical spine are able to cause neck pain. Hereby, the type of surgery and also the number of segments treated is relevant. After fusion surgery, the so-called adjacent level syndrome is a possible pain source. After arthroplasty, the load of the facet joints in the index segment increases and can cause pain. Further, degenerative alterations progress. In general, two fundamentally different therapeutic approaches for interventional pain therapy for the cervical spine exist: Treatment of facet joint pain with radiofrequency denervation or facet nerve blocks, and epidural injections either via a transforaminal or via an interlaminar approach. The literature about interventions in CPSS is limited to single studies with a small number of patients. However, some evidence exists for these procedures. Interventional pain therapies are eligible as a target-specific therapy option. However, the risk of theses procedures (especially transforaminal epidural injections) must be weighed against the benefit.
Collapse
|
25
|
Welke B, Schwarze M, Hurschler C, Book T, Magdu S, Daentzer D. In vitro investigation of a new dynamic cervical implant: comparison to spinal fusion and total disc replacement. 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 2015; 25:2247-54. [PMID: 26684468 DOI: 10.1007/s00586-015-4361-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 12/07/2015] [Accepted: 12/07/2015] [Indexed: 12/28/2022]
Abstract
PURPOSE AND METHODS For the treatment of degenerative disc diseases of the cervical spine, anterior cervical discectomy and fusion (ACDF) still represents the standard procedure. However, long term clinical studies have shown a higher incidence of pathologies in the adjacent segments. As an alternative to spinal fusion, cervical total disc replacement (cTDR) or dynamically implants were increasingly used. This in vitro study analyzed the kinematics and intradiscal pressures in seven multi-segmental human cervical spine using hybrid multidirectional test method. The aim of our study was to compare the intact condition with a single-level dynamic stabilization with DCI(®), with cTDR (activC(®)) and with simulated ACDF (CeSPACE(®) cage and CASPAR plate). RESULTS No significant changes in the kinematics and pressures were observed in all segments after arthroplasty. The DCI(®) significantly decreased the motion of the treated segment in flexion/extension and lateral bending with some remaining residual mobility. Thereby the motion of the upper segment was increased significantly in flexion/extension. No significant changes of the intradiscal pressures were observed. With simulated fusion the motion of the indexed level was significantly decreased in flexion/extension and axial rotation with the greatest changes in the adjacent levels and the highest pressures. CONCLUSION Based on our biomechanical study the DCI(®) can pose an alternative to fusion, which has a lesser effect on adjacent levels. This might reduce the risk of long-term degeneration in those levels. In particular, the facet joint arthritis and kyphotic deformity, as a contraindication to the arthroplasty, could be a clinical application of the dynamic implant.
Collapse
Affiliation(s)
- Bastian Welke
- Laboratory for Biomechanics and Biomaterials, Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany.
| | - Michael Schwarze
- Laboratory for Biomechanics and Biomaterials, Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany
| | - Christof Hurschler
- Laboratory for Biomechanics and Biomaterials, Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany
| | - Thorsten Book
- Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany
| | - Stephan Magdu
- Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany
| | - Dorothea Daentzer
- Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany
| |
Collapse
|
26
|
Biomechanical Analysis of Cervical Disc Replacement and Fusion Using Single Level, Two Level, and Hybrid Constructs. Spine (Phila Pa 1976) 2015; 40:1578-85. [PMID: 26165217 DOI: 10.1097/brs.0000000000001044] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [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 comparing arthroplasty with fusion using human cadaveric C2-T1 spines. OBJECTIVE To compare the kinematics of the cervical spine after arthroplasty and fusion using single level, 2 level and hybrid constructs. SUMMARY OF BACKGROUND DATA Previous studies have shown that spinal levels adjacent to a fusion experience increased motion and higher stress which may lead to adjacent segment disc degeneration. Cervical arthroplasty achieves similar decompression but preserves the motion at the operated level, potentially decreasing the occurrence of adjacent segment disc degeneration. METHODS 11 specimens (C2-T1) were divided into 2 groups (BRYAN and PRESTIGE LP). The specimens were tested in the following order; intact, single level total disc replacement (TDR) at C5-C6, 2-level TDR at C5-C6-C7, fusion at C5-C6 and TDR at C6-C7 (Hybrid construct), and lastly a 2-level fusion. The intact specimens were tested up to a moment of 2.0 Nm. After each surgical intervention, the specimens were loaded until the primary motion (C2-T1) matched the motion of the respective intact state (hybrid control). RESULTS An arthroplasty preserved motion at the implanted level and maintained normal motion at the nonoperative levels. Arthrodesis resulted in a significant decrease in motion at the fused level and an increase in motion at the unfused levels. In the hybrid construct, the TDR adjacent to fusion preserved motion at the arthroplasty level, thereby reducing the demand on the other levels. CONCLUSION Cervical disc arthroplasty with both the BRYAN and PRESTIGE LP discs not only preserved the motion at the operated level, but also maintained the normal motion at the adjacent levels. Under simulated physiologic loading, the motion patterns of the spine with the BRYAN or PRESTIGE LP disc were very similar and were closer than fusion to the intact motion pattern. An adjacent segment disc replacement is biomechanically favorable to a fusion in the presence of a pre-existing fusion.
Collapse
|
27
|
Lazennec JY, Aaron A, Ricart O, Rakover JP. The innovative viscoelastic CP ESP cervical disk prosthesis with six degrees of freedom: biomechanical concepts, development program and preliminary clinical experience. EUROPEAN JOURNAL OF ORTHOPAEDIC SURGERY AND TRAUMATOLOGY 2015; 26:9-19. [PMID: 26341803 PMCID: PMC4705139 DOI: 10.1007/s00590-015-1695-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 08/21/2015] [Indexed: 12/20/2022]
Abstract
The viscoelastic cervical disk prosthesis ESP is an innovative one-piece deformable but cohesive interbody spacer. It is an evolution of the LP ESP lumbar disk implanted since 2006. CP ESP provides six full degrees of freedom about the three axes including shock absorbtion. The prosthesis geometry allows limited rotation and translation with resistance to motion (elastic return property) aimed at avoiding overload of the posterior facets. The rotation center can vary freely during motion. The concept of the ESP prosthesis is fundamentally different from that of the devices currently used in the cervical spine. The originality of the concept of the ESP® prosthesis led to innovative and intense testing to validate the adhesion of the viscoelastic component of the disk on the titanium endplates and to assess the mechanical properties of the PCU cushion. The preliminary clinical and radiological results with 2-year follow-up are encouraging for pain, function and kinematic behavior (range of motion and evolution of the mean centers of rotation). In this series, we did not observe device-related specific complications, misalignment, instability or ossifications. Additional studies and longer patient follow-up are needed to assess long-term reliability of this innovative implant.
Collapse
|
28
|
Radiographic Variables That May Predict Clinical Outcomes in Cervical Disk Replacement Surgery. ACTA ACUST UNITED AC 2015; 28:106-13. [DOI: 10.1097/bsd.0b013e31826a0c84] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
29
|
Daentzer D, Welke B, Hurschler C, Husmann N, Jansen C, Flamme CH, Richter BI. In vitro-analysis of kinematics and intradiscal pressures in cervical arthroplasty versus fusion--A biomechanical study in a sheep model with two semi-constrained prosthesis. Biomed Eng Online 2015; 14:27. [PMID: 25889378 PMCID: PMC4403750 DOI: 10.1186/s12938-015-0018-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 02/27/2015] [Indexed: 11/10/2022] Open
Abstract
Background As an alternative technique to arthrodesis of the cervical spine, total disc replacement (TDR) has increasingly been used with the aim of restoration of the physiological function of the treated and adjacent motions segments. The purpose of this experimental study was to analyze the kinematics of the target level as well as of the adjacent segments, and to measure the pressures in the proximal and distal disc after arthrodesis as well as after arthroplasty with two different semi-constrained types of prosthesis. Methods Twelve cadaveric ovine cervical spines underwent polysegmental (C2-5) multidirectional flexibility testing with a sensor-guided industrial serial robot. Additionally, pressures were recorded in the proximal and distal disc. The following three conditions were tested: (1) intact specimen, (2) single-level arthrodesis C3/4, (3) single-level TDR C3/4 using the Discover® in the first six specimens and the activ® C in the other six cadavers. Statistical analysis was performed for the total range of motion (ROM), the intervertebral ROM (iROM) and the intradiscal pressures (IDP) to compare both the three different conditions as well as the two disc prosthesis among each other. Results The relative iROM in the target level was always lowered after fusion in the three directions of motion. In almost all cases, the relative iROM of the adjacent segments was almost always higher compared to the physiologic condition. After arthroplasty, we found increased relative iROM in the treated level in comparison to intact state in almost all cases, with relative iROM in the adjacent segments observed to be lower in almost all situations. The IDP in both adjacent discs always increased in flexion and extension after arthrodesis. In all but five cases, the IDP in each of the adjacent level was decreased below the values of the intact specimens after TDR. Overall, in none of the analyzed parameters were statistically significantly differences between both types of prostheses investigated. Conclusion The results of this biomechanical study indicate that single-level implantation of semi-constrained TDR lead to a certain hypermobility in the treated segments with lowering the ROM in the adjacent levels in almost all situations.
Collapse
Affiliation(s)
- Dorothea Daentzer
- Orthopedic Department, Hannover Medical School, Diakoniekrankenhaus Annastift gGmbH, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany.
| | - Bastian Welke
- Laboratory for Biomechanics and Biomaterials, Department of Orthopedics, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany.
| | - Christof Hurschler
- Laboratory for Biomechanics and Biomaterials, Department of Orthopedics, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany.
| | - Nathalie Husmann
- Department of Radiology, Asklepios Clinic Nord, Standort Heidberg, Tangstedter Landstr. 400, 22417, Hamburg, Germany.
| | - Christina Jansen
- Department of Spine Surgery, Klinikum Bad Bramstedt GmbH, Oskar-Alexander-Str. 26, 24576, Bad Bramstedt, Germany.
| | - Christian Heinrich Flamme
- Clinic for Orthopedics and Traumatology, Asklepios Clinic Hamburg, Eißendorfer Pferdeweg 52, 21075, Hamburg, Germany.
| | - Berna Ida Richter
- Laboratory for Biomechanics and Biomaterials, Department of Orthopedics, Hannover Medical School, Anna-von-Borries-Str. 1-7, 30625, Hannover, Germany. .,Aesculap AG, Am Aesculap-Platz, 78532, Tuttlingen, Germany.
| |
Collapse
|
30
|
Matgé G, Berthold C, Gunness VRN, Hana A, Hertel F. Stabilization with the Dynamic Cervical Implant: a novel treatment approach following cervical discectomy and decompression. J Neurosurg Spine 2015; 22:237-45. [PMID: 25555050 DOI: 10.3171/2014.10.spine131089] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Although cervical total disc replacement (TDR) has shown equivalence or superiority to anterior cervical discectomy and fusion (ACDF), potential problems include nonphysiological motion (hypermobility), accelerated degeneration of the facet joints, particulate wear, and compromise of the mechanical integrity of the endplate during device fixation. Dynamic cervical stabilization is a novel motion-preserving concept that facilitates controlled, limited flexion and extension, but prevents axial rotation and lateral bending, thereby reducing motion across the facet joints. Shock absorption of the Dynamic Cervical Implant (DCI) device is intended to protect adjacent levels from accelerated degeneration. METHODS The authors conducted a prospective evaluation of 53 consecutive patients who underwent DCI stabilization for the treatment of 1-level (n = 42), 2-level (n = 9), and 3-level (n = 2) cervical disc disease with radiculopathy or myelopathy. Forty-seven patients (89%) completed all clinical and radiographic outcomes at a minimum of 24 months. Clinical outcomes consisted of Neck Disability Index (NDI) and visual analog scale (VAS) scores, neurological function at baseline and at latest follow-up, as well as patient satisfaction. Flexion-extension radiography was evaluated for device motion, implant migration, subsidence, and heterotopic ossification. Cervical sagittal alignment (Cobb angle), functional spinal unit (FSU) angle, and range of motion (ROM) at index and adjacent levels were evaluated with WEB 1000 software. RESULTS The NDI score, VAS neck and arm pain scores, and neurological deficits were significantly reduced at each postoperative time point compared with baseline (p < 0.0001). At 24 months postoperatively, 91% of patients were very satisfied and 9% somewhat satisfied, while 89% would definitely and 11% would probably elect to have the same surgery again. In 47 patients with 58 operated levels, the radiographic assessment showed good motion (5°-12°) of the device in 57%, reduced motion (2°-5°) in 34.5%, and little motion (0-2°) in 8.5%. The Cobb and FSU angles improved, showing a clear tendency for lordosis with the DCI. Motion greater than 2° of the treated segment could be preserved in 91.5%, while 8.5% had a near segmental fusion. Mean ROM at index levels demonstrated satisfying motion preservation with DCI. Mean ROM at upper and lower adjacent levels showed maintenance of adjacent-level kinematics. Heterotopic ossification, including 20% minor and 15% major, had no direct impact on clinical results. There were 2 endplate subsidences detected with an increased segmental lordosis. One asymptomatic anterior device migration required reoperation. Three patients underwent a secondary surgery in another segment during follow-up, twice for a new disc herniation and once for an adjacent degeneration. There was no posterior migration and no device breakage. CONCLUSIONS Preliminary results indicate that the DCI implanted using a proper surgical technique is safe and facilitates excellent clinical outcomes, maintains index-and adjacent-level ROM in the majority of cases, improves sagittal alignment, and may be suitable for patients with facet arthrosis who would otherwise not be candidates for cervical TDR. Shock absorption together with maintained motion in the DCI may protect adjacent levels from early degeneration in longer follow-up.
Collapse
Affiliation(s)
- Guy Matgé
- National Neurosurgical Department, Centre Hospitalier de Luxembourg, Luxembourg City, Luxembourg
| | | | | | | | | |
Collapse
|
31
|
Park J, Shin JJ, Lim J. Biomechanical Analysis of Disc Pressure and Facet Contact Force After Simulated Two-Level Cervical Surgeries (Fusion and Arthroplasty) and Hybrid Surgery. World Neurosurg 2014; 82:1388-93. [DOI: 10.1016/j.wneu.2014.06.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2013] [Accepted: 06/09/2014] [Indexed: 10/25/2022]
|
32
|
Zhu R, Yang H, Wang Z, Wang G, Shen M, Yuan Q. Comparisons of three anterior cervical surgeries in treating cervical spondylotic myelopathy. BMC Musculoskelet Disord 2014; 15:233. [PMID: 25012927 PMCID: PMC4110372 DOI: 10.1186/1471-2474-15-233] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Accepted: 07/03/2014] [Indexed: 12/29/2022] Open
Abstract
Background Anterior cervical discectomy and fusion (ACDF) was one of the preferred treatments for degenerative cervical spondylosis. However, the motion of adjacent segment was significantly increased after operation. So cervical disc arthroplasty have been suggested to keep the motion of adjacent segment. A new implant named dynamic cervical implant (DCI) has been developed to keep the motion of adjacent segment. Methods We retrospectively reviewed 91 patients treated for single level cervical spondylotic myelopathy with anterior cervical discectomy and fusion (ACDF), dynamic cervical implant (DCI) and cervical total disc replacement (CTDR) between sep 2009 and Mar 2011 in our hospital. They were divided into three groups by surgical methods: ACDF group (group A, 34 cases), DCI group (group B, 25 cases), CTDR group (group C, 32 cases). Operation time, intraoperative blood loss, preoperative and postoperative JOA score and JOA recovery rate were compared among the three groups. Pre-and postoperative hyperextension and hyperflexion radiograms were observed to measure range of motion (ROM) of C2–7, operative and adjacent levels. Results There was no statistical difference in operative time, intraoperative blood loss, and JOA recovery rate (P > 0.05) among three groups. But the differences of their postoperative JOA scores and preoperative JOA scores were of statistical significance (P < 0.05). Compared the pre-and postoperative ROM of C2–7, operative, upper and lower levels of each group respectively, the difference between preoperative ROM and postoperative ROM of group A were of statistically significant (P < 0.05), while was no statistically significant of group C (P > 0.05). There was no statistically significant difference between preoperative ROM and postoperative ROM of upper and lower levels in group B (P > 0.05), but had statistically significance of C2–7 and operative levels (P < 0.05). Conclusions Three operations are effective therapies for single level cervical spondylotic myelopathy. But each group has respective advantages and disadvantages.
Collapse
Affiliation(s)
- RuoFu Zhu
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University, 188 Shizi Street, Suzhou, China.
| | | | | | | | | | | |
Collapse
|
33
|
LIN CHIENYU, CHUANG SHIHYOUENG, CHIANG CHANGJUNG, TSUANG YANGHWEI, CHEN WENGPIN. FINITE ELEMENT ANALYSIS OF CERVICAL SPINE WITH DIFFERENT CONSTRAINED TYPES OF TOTAL DISC REPLACEMENT. J MECH MED BIOL 2014. [DOI: 10.1142/s0219519414500389] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Various designs of cervical total disc replacement (CTDR) have been introduced and employed in an attempt to avoid disadvantages of the fusion surgery. The purposes of this study were to evaluate the effects of the range of motion (ROM), the instantaneous center of rotation (ICR) and the facet joint force (FJF) with different constrained types of CTDR devices. A three-dimensional finite element (FE) model of intact cervical spine (C3-7) was made from CT scans of a normal person and validated. Postoperative FE models simulating CTDR implantation at the C5-6 disc space were made for CTDR-I (constrained design) and CTDR-II (nonconstrained design), respectively. Hybrid protocol (intact: 1 Nm) with a compressive follower load of 73.6 N was applied at the superior endplate of the C3 vertebral body. The inferior endplate of C7 vertebral body was constrained in all directions. At the index level, CTDR-I showed a higher increase in segmental motion and FJF than CTDR-II in extension, lateral bending and axial rotation. The CTDR-II with an elastomer-type core reproduced a near physiological ICR of the intact model in extension and axial rotation. Abnormal kinetic and kinematic changes related to the CTDR may induce surgical level problems and cause long-term failure of spinal surgery.
Collapse
Affiliation(s)
- CHIEN-YU LIN
- Department of Mechanical Engineering, National Taipei University of Technology, Taipei, Taiwan
| | - SHIH-YOUENG CHUANG
- Department of Orthopaedic Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - CHANG-JUNG CHIANG
- Department of Orthopaedics, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan
| | - YANG-HWEI TSUANG
- Department of Orthopaedics, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan
| | - WENG-PIN CHEN
- Department of Mechanical Engineering, National Taipei University of Technology, Taipei, Taiwan
| |
Collapse
|
34
|
Biomechanical evaluation of a metal-on-metal cervical intervertebral disc prosthesis. Spine J 2013; 13:1640-9. [PMID: 24094992 DOI: 10.1016/j.spinee.2013.06.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Revised: 12/17/2012] [Accepted: 06/01/2013] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT In vitro nondestructive flexibility testing of the CerviCore total disc replacement (TDR) was performed. It was hypothesized that TDR would not significantly alter biomechanics relative to intact, whereas rigid fixation would cause significant changes. PURPOSE To assess the ability of a cervical metal-on-metal saddle-shaped TDR to replicate normal biomechanics in vitro. STUDY DESIGN Human cadaveric flexibility experiment. METHODS Nine human cadaveric C3-T1 specimens were tested intact, after TDR and after anterior plating. Flexion, extension, lateral bending, and axial rotation were induced by pure moments; flexion-extension was then repeated using a simplified muscle force model with 70-N follower load. Optical markers measured three-dimensional intervertebral motion, and eight points of laminar surface strain were recorded near the left and right C5-C6 facet joints. Biomechanical parameters studied included range of motion (ROM), lax zone (LZ), angular coupling pattern, sagittal instantaneous axis of rotation (IAR), and facet loads normal to the facet joint plane. Mean values of parameters were compared statistically using repeated measures analysis of variance and Holm-Sidak tests. RESULTS Total disc replacement caused significant reduction in ROM during extension (p=.004) and significant reduction in LZ during lateral bending (p=.01). However, plating significantly reduced both ROM and LZ during flexion, extension, and lateral bending (p<.006). Sagittal IAR shifted relative to intact by 3.6 mm after TDR (p>.05) and 6.5 mm after plating (p>.05). Coupled axial rotation/degree lateral bending was 99% of intact after TDR but 76% of intact after plating (p=.15). Coupled lateral bending/degree axial rotation was 95% of intact after TDR but 85% of intact after plating (p=.43). Neither construct altered facet loads from intact. CONCLUSIONS With regard to ROM, LZ, IAR, and coupling, deviations from intact biomechanics were less substantial after TDR than after plating. Facet load alterations were minimal with either construct. Our results show that this particular TDR permits ROM and maintains some measures of kinematics in a cadaver model.
Collapse
|
35
|
Mo ZJ, Zhao YB, Wang LZ, Sun Y, Zhang M, Fan YB. Biomechanical effects of cervical arthroplasty with U-shaped disc implant on segmental range of motion and loading of surrounding soft tissue. 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; 23:613-21. [PMID: 24154828 DOI: 10.1007/s00586-013-3070-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Revised: 09/09/2013] [Accepted: 10/09/2013] [Indexed: 12/12/2022]
Abstract
PURPOSE Various design concepts have been adopted in cervical disc prostheses, including sliding articulation and standalone configuration. This study aimed to evaluate the biomechanical effects of the standalone U-shaped configuration on the cervical spine. METHODS Based on an intact finite element model of C3-C7, a standalone U-shaped implant (DCI) was installed at C5-C6 and compared with a sliding articulation design (Prodisc-C) and an anterior fusion system. The range of motion (ROM), adjacent intradiscal pressure (IDP) and capsular ligament strain were calculated under different spinal motions. RESULTS Compared to the intact configuration, the ROM at C5-C6 was reduced by 90% after fusion, but increased by 70% in the Prodisc-C model, while the maximum percentage change in the DCI model was 30% decrease. At the adjacent segments, up to 32% increase in ROM happened after fusion, while up to 34% decrease occurred in Prodisc-C model and 17% decrease in DCI model. The IDP increased by 11.6% after fusion, but decreased by 5.6 and 6.3% in the DCI and Prodisc-C model, respectively. The capsular ligament strain increased by 147% in Prodisc-C and by 13% in the DCI model. The DCI implant exhibited a high stress distribution. CONCLUSIONS Spinal fusion resulted in compensatory increase of ROM at the adjacent sites, thereby elevating the IDP. Prodisc-C resulted in hyper-mobility at the operative site that led to an increase of ligament force and strain. The U-shaped implant could maintain the spinal kinematics and impose minimum influence on the adjacent soft tissues, despite the standalone configuration encountering the disadvantages of high stress distribution.
Collapse
Affiliation(s)
- Zhong Jun Mo
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, Beijing Key Laboratory for Optimal Design and Evaluation Technology of Implantable & Interventional Medical Devices, International Joint Research Center of Aerospace Biotechnology and Medical Engineering of Ministry of Science and Technology, School of Biological Science and Medical Engineering, Beihang University, XueYuan Road No.37, HaiDian District, Beijing, 100191, People's Republic of China
| | | | | | | | | | | |
Collapse
|
36
|
Davis RJ, Kim KD, Hisey MS, Hoffman GA, Bae HW, Gaede SE, Rashbaum RF, Nunley PD, Peterson DL, Stokes JK. Cervical total disc replacement with the Mobi-C cervical artificial disc compared with anterior discectomy and fusion for treatment of 2-level symptomatic degenerative disc disease: a prospective, randomized, controlled multicenter clinical trial: clinical article. J Neurosurg Spine 2013; 19:532-45. [PMID: 24010901 DOI: 10.3171/2013.6.spine12527] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECT Cervical total disc replacement (TDR) is intended to treat neurological symptoms and neck pain associated with degeneration of intervertebral discs in the cervical spine. Anterior cervical discectomy and fusion (ACDF) has been the standard treatment for these indications since the procedure was first developed in the 1950s. While TDR has been shown to be a safe and effective alternative to ACDF for treatment of patients with degenerative disc disease (DDD) at a single level of the cervical spine, few studies have focused on the safety and efficacy of TDR for treatment of 2 levels of the cervical spine. The primary objective of this study was to rigorously compare the Mobi-C cervical artificial disc to ACDF for treatment of cervical DDD at 2 contiguous levels of the cervical spine. METHODS This study was a prospective, randomized, US FDA investigational device exemption pivotal trial of the Mobi-C cervical artificial disc conducted at 24 centers in the US. The primary clinical outcome was a composite measure of study success at 24 months. The comparative control treatment was ACDF using allograft bone and an anterior plate. A total of 330 patients were enrolled, randomized, and received study surgery. All patients were diagnosed with intractable symptomatic cervical DDD at 2 contiguous levels of the cervical spine between C-3 and C-7. Patients were randomized in a 2:1 ratio (TDR patients to ACDF patients). RESULTS A total of 225 patients received the Mobi-C TDR device and 105 patients received ACDF. At 24 months only 3.0% of patients were lost to follow-up. On average, patients in both groups showed significant improvements in Neck Disability Index (NDI) score, visual analog scale (VAS) neck pain score, and VAS arm pain score from preoperative baseline to each time point. However, the TDR patients experienced significantly greater improvement than ACDF patients in NDI score at all time points and significantly greater improvement in VAS neck pain score at 6 weeks, and at 3, 6, and 12 months postoperatively. On average, patients in the TDR group also maintained preoperative segmental range of motion at both treated segments immediately postoperatively and throughout the study period of 24 months. The reoperation rate was significantly higher in the ACDF group at 11.4% compared with 3.1% for the TDR group. Furthermore, at 24 months TDR demonstrated statistical superiority over ACDF based on overall study success rates. CONCLUSIONS The results of this study represent the first available Level I clinical evidence in support of cervical arthroplasty at 2 contiguous levels of the cervical spine using the Mobi-C cervical artificial disc. These results continue to support the use of cervical arthroplasty in general, but specifically demonstrate the advantages of 2-level arthroplasty over 2-level ACDF. Clinical trial registration no.: NCT00389597 (ClinicalTrials.gov).
Collapse
|
37
|
Li J, Liang L, Ye XF, Qi M, Chen HJ, Yuan W. Cervical arthroplasty with Discover prosthesis: clinical outcomes and analysis of factors that may influence postoperative range of motion. 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; 22:2303-9. [PMID: 23877109 DOI: 10.1007/s00586-013-2897-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2012] [Revised: 05/05/2013] [Accepted: 07/07/2013] [Indexed: 12/22/2022]
Abstract
PURPOSE The aim of this current study was to analyze the clinical outcomes after Discover cervical disc replacement and its effects on maintaining cervical lordosis and range of motion (ROM). The possible factors influencing postoperative ROM were analyzed. METHOD 27 men and 28 women with a mean age of 46.4 ± 8.7 years were prospectively followed up for 2 years. Clinical outcomes were assessed using Japanese Orthopedic Association (JOA), Neck Disability Index (NDI), visual analog scale (VAS) and Odom's criteria. Radiographic information including segment and overall alignment, functional spinal unit (FSU) and overall ROM, and disc heights were prospectively collected during the follow-up. The correlations between the postoperative FSU ROM at last follow-up and influencing factors were analyzed. RESULTS Mean NDI, JOA and VAS scores showed statistical improvements at last follow-up. Anterior migration of the prosthesis was detected in six cases. Heterotopic ossification was observed in ten patients. Mean FSU angle, endplate angle of the treated level and mean overall cervical alignment were all improved significantly at last follow-up (P < 0.001). However, mean FSU ROM of the treated segment significantly decreased postoperatively (P = 0.008), while mean overall ROM showed no significant differences. A significant correlation was found between preoperative FSU ROM and postoperative FSU ROM by the Pearson correlation coefficient (r = 0.325, P = 0.034). Multiple linear regression analysis confirmed that preoperative FSU ROM contributed independently to a model with a coefficient of determination of 0.37 (P = 0.034). CONCLUSIONS In the 2 years follow-up, the Discover cervical disc arthroplasty has provided satisfactory clinical outcomes. It was able to substantially restore segment and overall cervical alignment while partially maintaining segment and overall cervical ROM. Additionally, we found that postoperative FSU ROM positively correlated with preoperative FSU ROM.
Collapse
Affiliation(s)
- Jun Li
- Department of Orthopaedic Surgery, Changzheng Hospital of the Second Military Medical University, Shanghai, 200003, China
| | | | | | | | | | | |
Collapse
|
38
|
Chen Y, Wang X, Lu X, Yang H, Chen D. Cervical disk arthroplasty versus ACDF for preoperative reducible kyphosis. Orthopedics 2013; 36:e958-65. [PMID: 23823056 DOI: 10.3928/01477447-20130624-29] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Cervical total disk arthroplasty has proven to be an effective and safe alternative for anterior cervical diskectomy and fusion (ACDF) for the treatment of cervical disk degenerative disease. However, whether and when cervical disk arthroplasty is indicated for preoperative cervical spine kyphosis is unclear. In the authors' clinical experiences, preoperative kyphosis can generally be divided into reducible and irreducible forms according to the results of dynamic flexion-extension lateral radiographs. Reducible kyphosis is mostly related to local disk prolapse, clinical symptoms, and musculature weakness, but irreducible kyphosis is always associated with significant cervical degeneration or congenital bone malformation. In this study, 32 patients with preoperative reducible kyphosis were randomized in a 1:1 ratio to either single-level total cervical arthroplasty with the Discover cervical disk prosthesis (DePuy Spine, Raynham, Massachusetts) (arthroplasty group) or single-level ACDF with a polyetheretherketone cage and plate (ACDF group). No significant differences existed in clinical and radiological results at 2-year follow-up between the arthroplasty and ACDF groups. The global and functional spinal unit angles of the arthroplasty group were significantly lower than those of the ACDF group 6 months postoperatively, which was consistent with the result of the comparison in Neck Disability Index score. However, the sagittal alignment of the overall cervical spine and the treated segment and the Neck Disability Index score significantly improved after 6 months in the arthroplasty group but not in the ACDF group. Therefore, preoperative reducible kyphosis is not a contraindication for cervical total disk arthroplasty. However, neck strength-building exercises should be emphasized for the postoperative rehabilitation after cervical total disk arthroplasty.
Collapse
Affiliation(s)
- Yu Chen
- Department of Spine Surgery, Orthopedics Research Institute of the Chinese People’s Liberation Army, Changzheng Hospital, Second Military Medical University, Shanghai, China.
| | | | | | | | | |
Collapse
|
39
|
Vorsic M, Bunc G. ProDisc-C versus fusion with Cervios chronOS prosthesis in cervical degenerative disc disease: Is there a difference at 12 months? EVIDENCE-BASED SPINE-CARE JOURNAL 2013; 1:51-6. [PMID: 23544025 PMCID: PMC3609006 DOI: 10.1055/s-0028-1100894] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Study design: Prospective cohort study. Objective: The aim of the study was to compare clinical results and to determine differences in outcomes between anterior cervical discectomy and fusion (ACDF) and disc arthroplasty in patients treated for symptomatic cervical degenerative disc disease. Methods: Forty patients with cervical degenerative disc disease were treated with ProDisc-C disc arthroplasty and 40 patients with fusion using an intervetebral spacer with integrated fixation (Cervios chronoOS) implants without additional anterior fixation. Fifty disc prostheses were placed in the first group and 52 intervertebral spacers were implanted in the second group. Clinical outcomes were assessed before and 12 months following the procedure using the neck disability index (NDI) and visual analog scale (VAS) for neck and arm pain, with 15% improvement in NDI and 20% in VAS defined as a clinically significant. Results: Eighty patients with cervical degenerative disc disease with a mean age of 49.7 years were included in the study with a minimum follow-up of 12 months. The groups were similar at baseline both clinically and statistically (P > .05) except for age and VAS for arm pain. Both groups had a statistically significant improvement in NDI and VAS for neck and arm pain (P < .05) and the arthroplasty group had a better improvement according to NDI (74.3% of patients in the arthroplasty group achieved ≥15% improvement in NDI versus 65.7% of patients in ACDF group). Conclusions: Both ProDisc C and Cervios chronoOS prostheses resulted in significant pain reduction and functional outcome for the patients with slightly better results in the group treated with disc arthroplasty 12 months after the surgery.
Collapse
Affiliation(s)
- Matjaz Vorsic
- University Hospital Maribor, Department of Neurosurgery; Maribor, Slovenia
| | | |
Collapse
|
40
|
Abstract
Symptomatic adjacent-level disease after cervical fusion has led to the development and testing of several disc-replacement prostheses. Randomized controlled trials of cervical disc replacement (CDR) compared with anterior cervical discectomy and fusion (ACDF) have demonstrated at least equivalent clinical results for CDR with similar or lower complication rates. Biomechanical, kinematic, and radiographic studies of CDR reveal that the surgical level and adjacent vertebral level motion and center of rotation more closely mimic the native state. Lower intradiscal pressures adjacent to CDR may help decrease the incidence of adjacent spinal-level disease, but long-term follow-up is necessary to evaluate this theory.
Collapse
Affiliation(s)
- Garrick W Cason
- Department of Orthopaedic Surgery, William Beaumont Hospital, Royal Oak, Michigan, USA.
| | | |
Collapse
|
41
|
Chen Y, He Z, Yang H, Wang X, Chen D. Clinical and radiological results of total disc replacement in the cervical spine with preoperative reducible kyphosis. INTERNATIONAL ORTHOPAEDICS 2012; 37:463-8. [PMID: 23271693 DOI: 10.1007/s00264-012-1754-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 12/09/2012] [Indexed: 05/27/2023]
Abstract
PURPOSE To investigate the clinical and radiological results of total disc replacement (TDR) in the cervical spine with preoperative reducible kyphosis, and discuss when TDR is indicated for the patients with preoperative kyphosis. METHODS Fifty-two patients who underwent single-level cervical TDR from June 2008 to May 2010 were included in this study. TDR was indicated for patients with preoperative lordosis or reducible kyphosis, and the patients were divided into a lordotic group (preoperative global angle of ≥0°) and kyphotic group (preoperative global angle of <0°). Clinical results were evaluated using the Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS) score and Neck Disablity Index (NDI). For radiological evaluation, the global and functional spinal unit (FSU) angles and the global and FSU range of motion were measured preoperatively and postoperatively. RESULTS The mean NDI in the kyphotic group was significantly higher than that in the lordotic group preoperatively and at six months postoperatively, but the groups showed no significant differences in JOA score, VAS score and NDI at the two year follow-up. The mean global and FSU angles in the kyphotic group were significantly lower than those in the lordotic group preoperatively and at six months postoperatively, but they gradually improved postoperatively. The differences lost significance at the two year follow-up. CONCLUSIONS Postoperative cervical kyphosis had adverse effects on the NDI after TDR. Artificial discs, symptom relief, and neck functional exercises may contribute to correction of preoperative reducible kyphosis at different stages after cervical TDR. Preoperative reducible kyphosis should not be an independent contraindication for cervical TDR.
Collapse
Affiliation(s)
- Yu Chen
- Orthopedic Research Institute of the Chinese People's Liberation Army, Department of Orthopedic Surgery, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | | | | | | | | |
Collapse
|
42
|
Crawford NR, Baek S, Sawa AGU, Safavi-Abbasi S, Sonntag VKH, Duggal N. Biomechanics of a fixed-center of rotation cervical intervertebral disc prosthesis. Int J Spine Surg 2012; 6:34-42. [PMID: 25694869 PMCID: PMC4300875 DOI: 10.1016/j.ijsp.2011.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Past in vitro experiments studying artificial discs have focused on range of motion. It is also important to understand how artificial discs affect other biomechanical parameters, especially alterations to kinematics. The purpose of this in vitro investigation was to quantify how disc replacement with a ball-and-socket disc arthroplasty device (ProDisc-C; Synthes, West Chester, Pennsylvania) alters biomechanics of the spine relative to the normal condition (positive control) and simulated fusion (negative control). METHODS Specimens were tested in multiple planes by use of pure moments under load control and again in displacement control during flexion-extension with a constant 70-N compressive follower load. Optical markers measured 3-dimensional vertebral motion, and a strain gauge array measured C4-5 facet loads. RESULTS Range of motion and lax zone after disc replacement were not significantly different from normal values except during lateral bending, whereas plating significantly reduced motion in all loading modes (P < .002). Plating but not disc replacement shifted the location of the axis of rotation anteriorly relative to the intact condition (P < 0.01). Coupled axial rotation per degree of lateral bending was 25% ± 48% greater than normal after artificial disc replacement (P = .05) but 37% ± 38% less than normal after plating (P = .002). Coupled lateral bending per degree of axial rotation was 37% ± 21% less than normal after disc replacement (P < .001) and 41% ± 36% less than normal after plating (P = .001). Facet loads did not change significantly relative to normal after anterior plating or arthroplasty, except that facet loads were decreased during flexion in both conditions (P < .03). CONCLUSIONS In all parameters studied, deviations from normal biomechanics were less substantial after artificial disc placement than after anterior plating.
Collapse
Affiliation(s)
- Neil R Crawford
- Spinal Biomechanics Laboratory, Barrow Neurological Institute, Phoenix, AZ
| | - Seungwon Baek
- Spinal Biomechanics Laboratory, Barrow Neurological Institute, Phoenix, AZ
| | - Anna G U Sawa
- Spinal Biomechanics Laboratory, Barrow Neurological Institute, Phoenix, AZ
| | - Sam Safavi-Abbasi
- Department of Neurosurgery, College of Medicine, University of Oklahoma, Oklahoma City, OK
| | - Volker K H Sonntag
- Spinal Biomechanics Laboratory, Barrow Neurological Institute, Phoenix, AZ
| | - Neil Duggal
- Department of Neurological Surgery, London Health Sciences Centre, London, Ontario, Canada
| |
Collapse
|
43
|
|
44
|
Bauman JA, Jaumard NV, Guarino BB, Weisshaar CL, Lipschutz DE, Welch WC, Winkelstein BA. Facet joint contact pressure is not significantly affected by ProDisc cervical disc arthroplasty in sagittal bending: a single-level cadaveric study. Spine J 2012; 12:949-59. [PMID: 22975463 DOI: 10.1016/j.spinee.2012.08.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 06/07/2012] [Accepted: 08/07/2012] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT Total disc arthroplasty is a motion-preserving spinal procedure that has been investigated for its impact on spinal motions and adjacent-level degeneration. However, the effects of disc arthroplasty on facet joint biomechanics remain undefined despite the critical role of these posterior elements on guiding and limiting spinal motion. PURPOSE The goal was to measure the pressure in the facet joint in cadaveric human cervical spines subjected to sagittal bending before and after implantation of the ProDisc-C (Synthes Spine Company, L.P, West Chester, PA, USA). STUDY DESIGN A biomechanical study was performed using cadaveric human cervical spines during sagittal bending in the intact and implanted conditions. METHODS Seven C2-T1 osteoligamentous cadaveric cervical spines were instrumented with a transducer to measure the C5-C6 facet pressure profiles during physiological sagittal bending, before and after implantation of a ProDisc-C at that level. Rotations of the index segment and global cervical spine were also quantified. RESULTS The mean C5-C6 range of motion significantly increased (p=.009) from 9.6°±5.1° in the intact condition to 16.2°±3.6° after implantation. However, despite such changes in rotation, there was no significant difference in the facet contact pressure during extension between the intact (64±30 kPa) and implanted (44±55 kPa) conditions. Similarly, there was no difference in facet pressure developed during flexion. CONCLUSIONS Although implantation of a ProDisc-C arthroplasty device at the C5-C6 level increases angular rotations, it does not significantly alter the local facet pressure at the index level in flexion or extension. Using a technique that preserves the capsular ligament, this study provides the first direct measurement of cervical facet pressure in a disc arthroplasty condition.
Collapse
Affiliation(s)
- Joel A Bauman
- Department of Neurosurgery, 3 Silverstein Hospital of the University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA
| | | | | | | | | | | | | |
Collapse
|
45
|
Goel VK, Faizan A, Palepu V, Bhattacharya S. Parameters that effect spine biomechanics following cervical disc replacement. 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 2012; 21 Suppl 5:S688-99. [PMID: 21598118 PMCID: PMC3377804 DOI: 10.1007/s00586-011-1816-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Revised: 04/11/2011] [Accepted: 04/13/2011] [Indexed: 10/18/2022]
Abstract
Total disc replacement (TDR) is expected to provide a more physiologic alternative to fusion. However, long-term clinical data proving the efficacy of the implants is lacking. Limited clinical data suggest somewhat of a disagreement between the in vitro biomechanical studies and in vivo assessments. This conceptual paper presents the potential biomechanical challenges affecting the TDR that should be addressed with a hope to improve the clinical outcomes and our understanding of the devices. Appropriate literature and our own research findings comparing the biomechanics of different disc designs are presented to highlight the need for additional investigations. The biomechanical effects of various surgical procedures are analyzed, reiterating the importance of parameters like preserving uncinate processes, disc placement and its orientation within the cervical spine. Moreover, the need for a 360° dynamic system for disc recipients who may experience whiplash injuries is explored. Probabilistic studies as performed already in the lumbar spine may explore high risk combinations of different parameters and explain the differences between "standard" biomechanical investigations and clinical studies. Development of a patient specific optimized finite element model that takes muscle forces into consideration may help resolve the discrepancies between biomechanics of TDR and the clinical studies. Factors affecting long-term performance such as bone remodeling, subsidence, and wear are elaborated. In vivo assessment of segmental spine motion has been, and continues to be, a challenge. In general, clinical studies while reporting the data have placed lesser emphasis on kinematics following intervertebral disc replacements. Evaluation of in vivo kinematics following TDR to analyze the quality and quantity of motion using stereoradiogrammetric technique may be needed.
Collapse
Affiliation(s)
- Vijay K Goel
- Departments of Bioengineering and Orthopaedic Surgery, 5046 NI, MS 303, Colleges of Engineering and Medicine, Engineering Center for Orthopaedic Research Excellence, University of Toledo, Toledo, OH 43606, USA.
| | | | | | | |
Collapse
|
46
|
Factors affecting reoperations after anterior cervical discectomy and fusion within and outside of a Federal Drug Administration investigational device exemption cervical disc replacement trial. Spine J 2012; 12:372-8. [PMID: 22425784 DOI: 10.1016/j.spinee.2012.02.005] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Accepted: 02/07/2012] [Indexed: 02/03/2023]
Abstract
BACKGROUND CONTEXT The excellent clinical results of five US Federal Drug Administration (FDA) trials approved for cervical total disc replacement (TDR) (Prestige [Medtronic Sofamor Danek, Memphis, TN, USA], Bryan [Medtronic Sofamor Danek], ProDisc-C [Synthes, West Chester, PA, USA], Kineflex|C [SpinalMotion, Mountain View, CA, USA], and Mobi-C [LDR Spine, Austin, TX, USA]) have recently been published. In these prospective randomized studies, superiority or equivalency of TDR was claimed, citing an 8.7% (23/265), 9.5% (21/221), 8.5% (9/106), 12.2% (14/115), and 6.2% (5/81) (mean = 9.02%) rate of additional related cervical surgical procedures within 2 years in control anterior cervical discectomy and fusion (ACDF) patients, respectively, compared with 1.8% (5/276), 5.8% (14/242), 1.9% (2/103), 11% (15/136), and 1.2% (2/164) (mean = 4.34%) in patients receiving the cervical TDR. The rate of reoperation within 2 years after ACDF seems unusually high. PURPOSE To assess the rate of and specific indications for early reoperation after ACDF in a cohort of patients receiving the ACDF as part of their customary care. These results are contrasted with similar patients receiving ACDF as the control arm of five FDA investigational device exemption (IDE) studies. STUDY DESIGN Multisurgeon retrospective clinical series from a single institution. PATIENT SAMPLE One hundred seventy-six patients with spondylotic radiculopathy or myelopathy underwent ACDF by three surgeons between 2001 and 2005 as part of their clinical practices. All patients had at least 2 years of follow-up with final follow-up within 6 months of completion of this study. OUTCOME MEASURES Cervical reoperation rates at 2-year follow-up and at 3.5-year follow-up. METHODS Review of medical records and telephone conversations were completed to determine the number of patients who had undergone a revision cervical procedure. RESULTS At final follow-up, complete data were available for 159 ACDF patients. Of the 48 patients who underwent single-level ACDF and met criteria for inclusion in the IDE studies, one patient (2.1%) required additional surgery (adjacent-segment degeneration) within 2 years, the duration of follow-up of the five published IDE studies. Of the 159 patients who received single or multilevel ACDF at a mean follow-up of 3.5 years, 12 patients (7.6%) had undergone revision cervical surgery, with three patients (1.9%) undergoing same-level revisions (posterior fusion) and nine patients (5.7%) undergoing adjacent anterior level fusions. Patients who underwent revision same-level surgery typically had the intervention within the first year (mean, 11 months), whereas those requiring adjacent-level fusions typically had surgery later (mean, 29 months). CONCLUSIONS The present study identifies a 2.1% rate of repeat surgery within 2 years of a single-level ACDF performed during routine clinical practice, which is lower than that reported in the control arm of the Prestige, ProDisc-C, Bryan, Kineflex|C, and Mobi-C FDA trials (mean=9%). Even with longer follow-up including multilevel cases, our reoperation rate (7.6%) compared favorably with the IDE rates. This discrepancy may reflect different thresholds for reoperation in the control arm of a device IDE study compared with routine clinical practice. Additionally, patients enrolled in the single-level-only IDE trial may have received multilevel procedures outside of the study. This factor could result in a higher rate of subsequent surgeries at adjacent levels not addressed at the index procedure. These data suggest that we need to better understand factors driving treatment and, in particular, decisions to reoperate both in and outside of a device trial.
Collapse
|
47
|
Tu TH, Wu JC, Fay LY, Ko CC, Huang WC, Cheng H. Vertebral body split fracture after a single-level cervical total disc replacement. J Neurosurg Spine 2012; 16:231-5. [DOI: 10.3171/2011.11.spine11210] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Cervical total disc replacement (TDR) is a viable option for the surgical treatment of degenerative disc disease. This 67-year-old nonsmoking male patient underwent single-level ProDisc-C cervical TDR at C5–6 without any intraoperative problem. His radicular pain improved and he had no neck pain immediately after the operation. However, on postoperative Day 3, a radiograph demonstrated a vertical split fracture of the C-5 vertebra. This fracture was managed conservatively, and 2 years postoperatively a follow-up CT scan demonstrated stable device position and fusion of the fracture. Although the linear fracture caused no neurological symptoms or device migration, the authors advocate prudence in selection and installation of keel-design prostheses, even in a single-level cervical TDR scenario.
Collapse
Affiliation(s)
- Tsung-Hsi Tu
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital; and
- 2School of Medicine and
| | - Jau-Ching Wu
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital; and
- 2School of Medicine and
- 3Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan
| | - Li-Yu Fay
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital; and
- 2School of Medicine and
| | - Chin-Chu Ko
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital; and
- 2School of Medicine and
| | - Wen-Cheng Huang
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital; and
- 2School of Medicine and
| | - Henrich Cheng
- 1Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital; and
- 2School of Medicine and
- 3Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan
| |
Collapse
|
48
|
Siemionow KB, Neckrysh S. Anterior approach for complex cervical spondylotic myelopathy. Orthop Clin North Am 2012; 43:41-52, viii. [PMID: 22082628 DOI: 10.1016/j.ocl.2011.09.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Cervical spondylotic myelopathy (CSM) is a slowly progressive disease resulting from age-related degenerative changes in the spine that can lead to spinal cord dysfunction and significant functional disability. The degenerative changes and abnormal motion lead to vertebral body subluxation, osteophyte formation, ligamentum flavum hypertrophy, and spinal canal narrowing. Repetitive movement during normal cervical motion may result in microtrauma to the spinal cord. Disease extent and location dictate the choice of surgical approach. Anterior spinal decompression and instrumented fusion is successful in preventing CSM progression and has been shown to result in functional improvement in most patients.
Collapse
Affiliation(s)
- Krzysztof B Siemionow
- Department of Orthopaedic Surgery, University of Illinois, 835 South Wolcott Avenue, Room E-270, Chicago, IL 60612, USA.
| | | |
Collapse
|
49
|
Segmental contribution toward total cervical range of motion: a comparison of cervical disc arthroplasty and fusion. Spine (Phila Pa 1976) 2011; 36:E1593-9. [PMID: 21508886 DOI: 10.1097/brs.0b013e31821cfd47] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN Prospective radiographic evaluation of patients that underwent cervical total disc replacement (TDR-C) or anterior cervical discectomy and fusion (ACDF) for one-level cervical disc disease. OBJECTIVE To evaluate the following: (1) total cervical range of motion (ROM) from C2 to C7, and (2) the relative contribution to total cervical ROM from the operative level and each adjacent level after one-level TDR-C or ACDF. SUMMARY OF BACKGROUND DATA The development of symptomatic adjacent segment disease after ACDF has served as the impetus for the development of motion-preserving alternatives, most notably cervical disc arthroplasty. While previous reports have evaluated device-level and total cervical motion, no study has comprehensively quantified the relative contribution made from each of the adjacent levels to total cervical ROM in TDR-C and ACDF. METHODS Radiographic review of 187 randomized patients from a multicenter, prospective, randomized trial comparing TDR-C with ACDF for one-level cervical disc disease. There were 93 TDR-C and 94 ACDF patients included. ROM measurements were performed independently using quantitative motion analysis, a custom digitized image stabilization software program, to evaluate total cervical ROM and relative contribution to total ROM from each level from C2 to C7 preoperatively and at 24 months. RESULTS The most common operative level was C5/C6 (57%) followed by C6/C7 (34%). At 2 years, the TDR-C group underwent a statistically greater improvement in total cervical ROM (+5.9°) compared with ACDF (-0.8°, P = 0.001). In TDR-C, the relative contributions to total cervical ROM from the operative level and each caudal and cranial adjacent level were statistically equivalent from baseline to 24 months. In contrast, ACDF patients had significantly reduced contribution to total cervical ROM from the operative level (by 15%, P < 0.001), and significantly elevated contribution from the caudal adjacent level (by 5.9%, P < 0.001), first cranial adjacent level (by 3.3%, P < 0.001), second cranial adjacent level (by 5.3%, P < 0.001), and third cranial adjacent level (by 3.0%, P < 0.001). CONCLUSION Compensation for the loss of motion at the operative level in ACDF is seen throughout the unfused cervical spine. Cervical disc arthroplasty, however, increases total cervical ROM compared with ACDF and maintains a physiologic distribution of ROM throughout the cervical spine at 2 years, potentially lowering the risk for adjacent segment breakdown.
Collapse
|
50
|
Uschold TD, Fusco D, Germain R, Tumialan LM, Chang SW. Cervical and lumbar spinal arthroplasty: clinical review. AJNR Am J Neuroradiol 2011; 33:1631-41. [PMID: 22033716 DOI: 10.3174/ajnr.a2758] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In contrast to cervical and lumbar fusion procedures, the principal aim of disk arthroplasty is to recapitulate the normal kinematics and biomechanics of the spinal segment affected. Following decompression of the neural elements, disk arthroplasty allows restoration of disk height and maintenance of spinal alignment. Based on clinical observations and biomechanical testing, the anticipated advantage of arthroplasty over standard arthrodesis techniques has been a proposed reduction in the development of symptomatic ALD. In this review of cervical and lumbar disk arthroplasty, we highlight the clinical results and experience with standard fusion techniques, incidence of ALD in the population of patients with surgical fusion, and indications for arthroplasty, as well as the biomechanical and clinical outcomes following arthroplasty. In addition, we introduce the devices currently available and provide a critical appraisal of the clinical evidence regarding arthroplasty procedures.
Collapse
Affiliation(s)
- T D Uschold
- Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona 85013, USA.
| | | | | | | | | |
Collapse
|