Single-Level In Vitro Kinematic Comparison of Novel Inline Cervical Interbody Devices With Intervertebral Screw, Anchor, or Blade

Study Design: In vitro cadaveric biomechanical study. Objective: To compare the biomechanics of integrated anchor and blade versus traditional screw fixation techniques for interbody fusion. Methods: Fifteen cadaveric cervical spines were divided into 3 equal groups (n = 5). Each spine was tested: intact, after discectomy (simulating an injury model), interbody spacer alone (S), integrated interbody spacer (iSA), and integrated spacer with lateral mass screw and rod fixation (LMS+iS). Each treatment group included integrated spacers with either screw, anchor, or blade integrated spacers. Constructs were tested in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) under pure moments (±1.5 N m). Results: Across all 3 planes, the following range of motion trend was observed: Injured > Intact > S > iSA > LMS+iS. In FE and LB, integrated anchor and blade significantly decreased motion compared with intact and injured conditions, before and after supplemental posterior fixation (P < .05). Comparing tested devices revealed biomechanical equivalence between screw, anchor, and blade fixation methods in all loading modes (P > .05). Conclusion: All integrated interbody devices reduced intact and injured motion; lateral mass screws and rods further stabilized the single motion segment. Comparing screw, anchor, or bladed integrated anterior cervical discectomy and fusion spacers revealed no significant differences.

[1]  R. Robinson,et al.  The treatment of certain cervical-spine disorders by anterior removal of the intervertebral disc and interbody fusion. , 1958, The Journal of bone and joint surgery. American volume.

[2]  W. Watters,et al.  ▪ Anterior Cervical Discectomy With and Without Fusion: Results, Complications, and Long‐term Follow‐up , 1994, Spine.

[3]  C. D. Brigham,et al.  Anterior Cervical Foraminotomy and Fusion|Surgical Technique and Results , 1995, Spine.

[4]  L. Claes,et al.  Testing criteria for spinal implants: recommendations for the standardization of in vitro stability testing of spinal implants , 1998, European Spine Journal.

[5]  M. Caterino,et al.  Asymptomatic Esophageal Perforation Caused by Late Screw Migration After Anterior Cervical Plating: Report of a Case and Review of Relevant Literature , 2002, Spine.

[6]  James R. Kenyon,et al.  Statistical Methods for the Analysis of Repeated Measurements , 2003, Technometrics.

[7]  W. Yue,et al.  Long-Term Results After Anterior Cervical Discectomy and Fusion With Allograft and Plating: A 5- to 11-Year Radiologic and Clinical Follow-up Study , 2005, Spine.

[8]  A. Patwardhan,et al.  Test protocols for evaluation of spinal implants. , 2006, The Journal of bone and joint surgery. American volume.

[9]  R A States,et al.  Precision and repeatability of the Optotrak 3020 motion measurement system , 2006, Journal of medical engineering & technology.

[10]  K. Bachus,et al.  Anterior cervical fixation: analysis of load-sharing and stability with use of static and dynamic plates. , 2006, The Journal of bone and joint surgery. American volume.

[11]  Gregory P. Lee,et al.  Anterior Cervical Discectomy and Fusion Associated Complications , 2007, Spine.

[12]  Paul S Saphier,et al.  Stress-shielding compared with load-sharing anterior cervical plate fixation: a clinical and radiographic prospective analysis of 50 patients. , 2007, Journal of neurosurgery. Spine.

[13]  K. Chin,et al.  Role of Plate Thickness as a Cause of Dysphagia After Anterior Cervical , 2007, Spine.

[14]  E. Helseth,et al.  Immediate (0–6 h), early (6–72 h) and late (>72 h) complications after anterior cervical discectomy with fusion for cervical disc degeneration; discharge six hours after operation is feasible , 2008, Acta Neurochirurgica.

[15]  R. Härtl,et al.  Anterior approaches to fusion of the cervical spine: a metaanalysis of fusion rates. , 2007, Journal of neurosurgery. Spine.

[16]  R. Sahjpaul.  Esophageal perforation from anterior cervical screw migration. , 2007, Surgical neurology.

[17]  D. Riew,et al.  Comparison of BRYAN Cervical Disc Arthroplasty With Anterior Cervical Decompression and Fusion: Clinical and Radiographic Results of a Randomized, Controlled, Clinical Trial , 2009, Spine.

[18]  M. Aebi.  Surgical treatment of upper, middle and lower cervical injuries and non-unions by anterior procedures , 2010, European Spine Journal.

[19]  N. Crawford,et al.  A New Stand-Alone Cervical Anterior Interbody Fusion Device: Biomechanical Comparison With Established Anterior Cervical Fixation Devices , 2009, Spine.

[20]  R. Delamarter,et al.  Results of the prospective, randomized, controlled multicenter Food and Drug Administration investigational device exemption study of the ProDisc-C total disc replacement versus anterior discectomy and fusion for the treatment of 1-level symptomatic cervical disc disease. , 2009, The spine journal : official journal of the North American Spine Society.

[21]  J. Tan,et al.  The difference in spine specimen dual-energy X-ray absorptiometry bone mineral density between in situ and in vitro scans. , 2010, The spine journal : official journal of the North American Spine Society.

[22]  R. Hoffmann,et al.  A New Zero-profile Implant for Stand-alone Anterior Cervical Interbody Fusion , 2011, Clinical orthopaedics and related research.

[23]  S. Khalil,et al.  A comparative biomechanical study of a novel integrated plate spacer for stabilization of cervical spine: an in vitro human cadaveric model. , 2012, Clinical biomechanics.

[24]  A. Patwardhan,et al.  Biomechanical evaluation of a low profile, anchored cervical interbody spacer device in the setting of progressive flexion-distraction injury of the cervical spine , 2012, European Spine Journal.

[25]  Zhao‐ming Zhong,et al.  Esophageal perforation related to anterior cervical spinal surgery , 2013, Journal of Clinical Neuroscience.

[26]  D. Coric,et al.  Prospective randomized study of cervical arthroplasty and anterior cervical discectomy and fusion with long-term follow-up: results in 74 patients from a single site. , 2013, Journal of neurosurgery. Spine.

[27]  G. Tomasello,et al.  Anterior cervical discectomy and fusion with ROI-C peek cage: cervical alignment and patient outcomes , 2014, European Spine Journal.

[28]  Aniruddh N. Nayak,et al.  Biomechanics of an integrated interbody device versus ACDF anterior locking plate in a single-level cervical spine fusion construct. , 2014, The spine journal : official journal of the North American Spine Society.

[29]  Huilin Yang,et al.  The application of zero-profile anchored spacer in anterior cervical discectomy and fusion , 2014, European Spine Journal.

[30]  K. Song,et al.  Current Concepts of Anterior Cervical Discectomy and Fusion: A Review of Literature , 2014, Asian spine journal.

[31]  Aniruddh N. Nayak,et al.  Biomechanical analysis of an interbody cage with three integrated cancellous lag screws in a two-level cervical spine fusion construct: an in vitro study. , 2014, The spine journal : official journal of the North American Spine Society.

[32]  V. Goel,et al.  A unique modular implant system enhances load sharing in anterior cervical interbody fusion: a finite element study , 2014, Biomedical engineering online.

[33]  Leónidas M. Quintana.  Complications in anterior cervical discectomy and fusion for cervical degenerative disc disease. , 2014, World neurosurgery.

[34]  A. Fujikawa,et al.  Stand-alone anchored cage versus cage with plating for single-level anterior cervical discectomy and fusion: a prospective, randomized, controlled study with a 2-year follow-up , 2015, European Journal of Orthopaedic Surgery & Traumatology.

[35]  M. Alimi,et al.  Anterior cervical discectomy and fusion with a zero-profile integrated plate and spacer device: a clinical and radiological study: Clinical article. , 2014, Journal of neurosurgery. Spine.

[36]  C. Hofstetter,et al.  Zero-profile Anchored Spacer Reduces Rate of Dysphagia Compared With ACDF With Anterior Plating , 2015, Journal of spinal disorders & techniques.

[37]  Yibing Li,et al.  The Efficiency of Zero-profile Implant in Anterior Cervical Discectomy Fusion: A Prospective Controlled Long-term Follow-up Study , 2015, Journal of spinal disorders & techniques.

[38]  Yueming Song,et al.  Comparison of anterior cervical discectomy and fusion with the zero-profile device versus plate and cage in treating cervical degenerative disc disease: A meta-analysis , 2016, Journal of Clinical Neuroscience.

[39]  R. Davis,et al.  The ROI-C zero-profile anchored spacer for anterior cervical discectomy and fusion: biomechanical profile and clinical outcomes , 2017, Medical devices.

[40]  Michael J. Collins,et al.  Comparison of Surgical Outcomes, Narcotics Utilization, and Costs After an Anterior Cervical Discectomy and Fusion: Stand-alone Cage Versus Anterior Plating , 2015, Clinical spine surgery.

[41]  Jonathan A. Harris,et al.  In Vitro Biomechanical and Fluoroscopic Study of a Continuously Expandable Interbody Spacer Concerning Its Role in Insertion Force and Segmental Kinematics , 2018, Asian spine journal.