Anterior Cervical Stabilization Research Articles

Correlation of Anterior Interbody Graft Choice With Patient-Reported Outcomes in Cervical Spine Trauma

Study Design:Ambispective observational cohort study.Objectives:Synthetic graft usage avoids morbidity associated with harvest and reduces operative time. This study aims to evaluate outcomes of anterior cervical stabilization surgery using a synthetic cage in comparison with iliac crest bone graft (ICBG) following cervical spine trauma.Methods:An ambispective review was conducted on patients from the Alfred Trauma Registry. Consecutive patients treated at a level 1 trauma center, aged 18 years and older who were treated with standalone anterior cervical stabilization following spine trauma (2011-2016) were included in the study. Primary outcome measures were patient overall satisfaction, Neck Disability Index (NDI), neck pain 10-point visual analogue scale (VAS-neck) and arm pain 10-point visual analogue scale (VAS-arm). Secondary outcome measures were radiographic evidence of fusion and rate of revision surgery. All patients had follow-up for at least 1 year.Results:Between 2011 and 2016, 114 traumatic disc levels in 104 patients were treated. ICBG was used in 32% and polyetheretherketone (PEEK) cage in 68% of the patients. Both groups had similar demographic metrics. There was no significant difference in primary outcome measures between the graft types: (1) patient satisfaction (P = .15), (2) NDI (P = .11), (3) VAS-neck (P = .13), and (4) VAS-arm (P = .20). Radiology based fusion assessment 6 months postsurgery did not show statistical significance (P = .10). The rates of revision surgery were similar.Conclusions:This study showed no significant difference in patient-reported outcome measures when comparing the usage of PEEK cage and ICBG in anterior stand alone cervical spine stabilization. Level 1 evidence studies are required to further investigate this finding.

A new multipartite plate system for anterior cervical spine surgery; finite element analysis

Background: There are numerous available plates, almost all of which are compact one-piece plates. During the placement of relatively long plates in the treatment of multi-level cervical pathologies, instrument related complications might appear. In order to overcome this potential problem, a novel ‘articulated plate system’ is designed. We aimed to delineate finite element analysis and mechanical evaluations.Material and methods: A new plate system consisting of multi partite structure for anterior cervical stabilization was designed. Segmental plates were designed for application onto the ventral surface of the vertebral body. Plates differed from 9 to13 mm in length. There are rods at one end and hooks at the other end. Terminal points consisted of either hooks or rods at one end but the other ends are blind. Finite element and mechanical tests of the construct were performed applying bending, axial loading, and distraction forces.Results: Finite element and mechanical testing results yielded the cut off values for functional failure and breakage of the system.Conclusions: The articulated system proved to be mechanically safe and it lets extension of the system on either side as needed. Ease of application needs further verification via a cadaveric study.

Hirayama Disease–Dynamic Cervical Compressive Myelopathy: An Indian Perspective

Introduction: Hirayama disease is a rare form of dynamic cervical flexion myelopathy. The incidence is more in Asian countries, like Japan, India, etc. Early diagnosis and treatment is the mainstay for the prognosis for this disease. Materials and methods: Our aim is to assess the outcome of anterior cervical stabilization in this disease. We had six patients who was diagnosed to have Hirayama disease in our center and underwent anterior cervical stabilization. Results: All six patients had fair to good outcome according to Odom’s criteria.

Ossification of the posterior longitudinal ligament: pathogenesis, management, and current surgical approaches

Ossification of the posterior longitudinal ligament (OPLL) is an important cause of cervical myelopathy that results from bony ossification of the cervical or thoracic posterior longitudinal ligament (PLL). It has been estimated that nearly 25% of patients with cervical myelopathy will have features of OPLL. Patients commonly present in their mid-40s or 50s with clinical evidence of myelopathy. On MR and CT imaging, this can be seen as areas of ossification that commonly coalesce behind the cervical vertebral bodies, leading to direct ventral compression of the cord. While MR imaging will commonly demonstrate associated changes in the soft tissue, CT scanning will better define areas of ossification. This can also provide the clinician with evidence of possible dural ossification. The surgical management of OPLL remains a challenge to spine surgeons. Surgical alternatives include anterior, posterior, or circumferential decompression and/or stabilization. Anterior cervical stabilization options include cervical corpectomy or multilevel anterior cervical corpectomy and fusion, while posterior stabilization approaches include instrumented or noninstrumented fusion or laminoplasty. Each of these approaches has distinct advantages and disadvantages. While anterior approaches may provide more direct decompression and best improve myelopathy scores, there is soft-tissue morbidity associated with the anterior approach. Posterior approaches, including laminectomy and fusion and laminoplasty, may be well tolerated in older patients. However, there often is associated axial neck pain and less improvement in myelopathy scores. In this review, the authors discuss the epidemiology, imaging findings, and clinical presentation of OPLL. The authors additionally discuss the merits of the different surgical techniques in the management of this challenging disease.

Anterior cervical stabilization using a semi-constrained cervical plate and titanium mesh cage for single level corpectomy

In this study we reviewed the treatment outcomes for 20 consecutive patients who underwent anterior 1-level cervical corpectomy and reconstruction using a titanium mesh cage and semi-constrained plating after an average follow-up of 14.8 months. Two groups, each of 10 patients, underwent surgery with 10-mm and 13-mm diameter cages, respectively. Bony fusion and the radiological outcome were evaluated using follow-up radiography and sagittal reconstructed CT scans. The radiographs revealed bony consolidation in 95% of the 20 patients during follow-up. Five cases of construct failure occurred after surgery:1 failure (10%) was encountered in the 10-mm cage group and 4 (40%) occurred in the 13-mm cage group ( P = 0.085). The failures were mainly the result of cage settling and screw-plate failure. Although the clinical outcomes and fusion rates for anterior cervical stabilization using a semi-constrained plate and titanium cage were favorable, further biomechanical evaluations and a prospective randomized study will be necessary to fully understand this dependence of implant failure on cage size.

An Assessment of Early Tracheostomy After Anterior Cervical Stabilization in Patients With Acute Cervical Spine Trauma

The optimal timing of tracheostomy after anterior cervical spine surgery remains controversial because of the potential for deep infection. The aims of this study were to compare the infection rates in patients requiring tracheostomy who underwent anterior versus posterior cervical spine surgery, and to report the timing of tracheostomy tube placement in such patients. All patients admitted to a referral Intensive Care Unit for spinal trauma from January 1998 until May 2005, who underwent surgical stabilization with instrumentation and also received a tracheostomy, were retrospectively evaluated for demographic data, severity of neurologic injury, and complications including infection to a surgical site and timing and type of tracheostomy procedure. We identified 71 patients, all who had a diagnosis of acute cervical spine injury. Thirty-two (45%) underwent anterior stabilization, 15 (21%) had posterior stabilizations, and 24 (34%) required both anterior and posterior approaches. The mean time from stabilization to tracheostomy for an anterior approach was 3.8 +/- 2.6 days. There was no significant difference in the timing of tracheostomy for different surgical approaches. Seventeen patients (25%) had a positive culture of their cervical and or tracheostomy incision site. Only one patient, however, had infection with the same organism at both the tracheostomy site and the anterior stabilization site. Suspected infection was managed with antibiotics and no further surgical intervention was required. Early tracheostomy after spinal stabilization is associated with a low risk of infection even after the anterior approach.

The Management of Bilateral Interfacetal Dislocation with Anterior Fixation in Cervical Spine : Comparison with Combined Antero-Posterior Fixation

Combined antero-posterior fixation has been a standard method for bilateral interfacetal dislocation in cervical spine. The purpose of this study is to evaluate the efficacy and complication of anterior cervical stabilization in treatment of bilateral interfacetal dislocation. A total of 65 cases of traumatic bilateral interfacetal dislocation in cervical spine who were managed in our institution, from Mar. 1997 to Feb. 2006, were included in this study. Closed reduction was tried in all cases before operation. If closed reduction was accomplished successfully, only anterior cervical fixation was performed (Group I), and attempted to place screws bicortically as possible with unicortical screws. If failed, posterior open reduction with fixation was first tried, followed by anterior cervical fixation (Group II). All patients were evaluated for neurological outcome and radiological evidence of healing. The Group I included 47 patients and the Group II, 18 patients. The improvement of Frankel grade and increase of mean cervical lordosis angles were not statistically different between two groups. Screw-plate system used did not influence the outcome. On follow up, solid bone fusion was evident and there were no cases of instability in both groups. Our study demonstrated that anterior cervical fixation on BID is safe and effective in comparison with combined antero-posterior cervical fixation.

採骨を要しない頸椎前方(除圧)固定術

採骨を要しない頸椎前方(除圧)固定術

Anterior cervical interbody fusion with rhBMP-2 and tantalum in a goat model

Background context: Tricortical autogenous iliac crest has long served as the gold standard for arthrodesis after cervical discectomy. The added morbidity resulting from bone graft harvest may be eliminated by the use of a biocompatible synthetic bone graft substitute with osteoconductive abilities, and when used with an osteoinductive agent, such as recombinant bone morphogenic protein (rhBMP)–2, it may facilitate arthrodesis similar to autograft. Purpose: To determine by radiographic and histologic analysis whether tantalum with and without rhBMP-2 can facilitate bony ingrowth and arthrodesis in an animal model. Study design/setting: Single-level anterior cervical discectomy and fusion was performed using a tantalum bone graft substitute with and without rhBMP-2 in a previously established goat model for anterior cervical fusion. Methods: Eight goats underwent single-level anterior cervical discectomy and stabilization with a porous tantalum implant. There were four goats in each experimental group. Group A underwent anterior cervical stabilization with tantalum alone, whereas in Group B rhBMP-2 was added to the tantalum implant. The goats were sacrificed at 12 weeks, and their cervical spines were removed for histologic and radiological analysis. Results: Only one of four goats in Group A had any bony ingrowth into the tantalum. Three of four goats in Group B demonstrated bony ingrowth. The average extent of bony ingrowth at the perimeter of the tantalum in Group A was 2.5% compared with 12.5% in Group B. Similarly, the volume of bony ingrowth within the tantalum was 2.5% in Group A and 10% in Group B. The difference was not statistically significant. Conclusions: The data in this pilot study suggest that tantalum may function as a synthetic osteoconductive bone graft substitute. The addition of rhBMP-2 may facilitate osteoinduction within a synthetic osteoconductive implant. The sample size in this study was too small for statistical significance. The present animal model as used in this study was inadequate for cervical arthrodesis where rigid implant fixation is desired.

Surgical outcome of single segment ventral fusion with plate osteosynthesis in therapy refractory chronic cervico-brachialgia

In anterior cervical stabilization, collapses of the grafted bone with resulting localized kyphosis and graft dislocation has been reported. It was the aim of this clinical trial to evaluate the benefit of additional plating while taking specific implant-related complications into account. The results of single level anterior cervical spinal fusion were evaluated. In 44 patients suffering from chronic cervical radicular pain with degenerative changes, arthrodesis with iliac-crest bone and plate fixation was performed. Apart from clinical parameters, the pre- and postoperative segmental kyphosis and cervical lordosis were evaluated. The total cervical alignment increased from 15.4 degrees to 18.5 degrees while the alignment of the fused segment increased from 2.6 degrees to 7.7 degrees. Postoperative decrease of correction did not occur. Bony fusion was confirmed in 95% after 12 months and 100% aller 36 months. Our results show that patients had more relief from radicular pain (80%) than from unspecific neck pain (66%). In single level anterior cervical fusion, additional plating successfully prevents dislocation of the bone graft and postoperative kyphosis. The clinical results and pseudarthrosis rate do not differ from studies without plating. Long. term follow-up studies are necessary to show the benefit of the reduced postoperative kyphosis.