Cervical Template to Optimize the Plate-To-Disc Distance in Instrumented Anterior Cervical Discectomies and Fusions: Instrumentation Assessment

BACKGROUND: An increased incidence of adjacent segment degeneration in the cervical spine has been associated with a plate-to-disc distance (PDD) of \u3c5 mm. OBJECTIVE: To introduce a template to size, position, and secure a cervical plate and ensure a 5-mm minimum PDD. METHODS: A prospective observational study was performed on 50 consecutive patients who had single-level anterior cervical discectomy and fusion (ACDF) using a cervical template. The cervical template was secured into the interbody spacer and assessed for length, PDD, and adequate vertebral body coverage. Holes were drilled through the template, which was then removed for cervical plate placement. Postoperative radiographs were assessed for PDD to adjacent segments, the angle from the vertical axis of the spine, and distance from midline. Neck Disability Index and visual analog scale scores for the neck and arm were obtained preoperatively and at 30-d and 90-d follow-up. RESULTS: Fifty patients underwent single-level ACDFs. The mean angle from the long axis of the spine was 2.4 (0.0-4.4) degrees; mean distance from midline was 1.3 (0.0-2.8) mm; and mean distance from the plate ends to the adjacent segments above was 5.4 (4.6-6.2) mm, and below, 5.1 (4.3-5.8) mm. CONCLUSION: A cervical template can reliably secure the midline and predetermine the size of the shortest cervical plate for adequately stabilizing the segment for arthrodesis. Use of a template standardizes the process of maximizing the PDD

Future Studies and Directions for the Optimization of Outcomes for Lumbar Spondylolisthesis

Randomized prospective studies show clear benefits for operative versus nonoperative management of symptomatic lumbar spondylolisthesis, but there is no universally accepted surgical treatment. This article presents options for surgical management of lumbar spondylolisthesis, reviews the clinical trials delineating the role and type of surgical intervention, and explores the directions of future investigations. The next decade will add further clarity to the surgical management of spondylolisthesis, not by randomized prospective trials, but by surgical registries. The power of “big data†offered by registries will likely become the vehicle best suited to amass data on current and novel therapies

Basilar Artery Thrombosis After Reduction of Cervical Spondyloptosis: A Cautionary Report - Case Report

Traumatic cervical spondyloptosis is a rare clinical entity typically associated with complete neurological deficit. The inherent mechanics of this fracture-dislocation pattern contorts the vertebral arteries in such a way that it may result in dissection or compromised flow through those vessels. Thus, intimal injury or thrombus from stasis of flow may result. Reduction of the spondyloptosis restores flow to the vertebral arteries, but it also may mobilize thrombus or propagate an intimal dissection within the previously contorted vessel. The authors review their experience in the care of a 43-year-old man who sustained C4-5 spondyloptosis while riding an all-terrain vehicle. On arrival, the patient demonstrated no motor function below C-4 but had sensation to the nipple line (American Spinal Injury Association Spinal Cord Injury Classification B). The patient\u27s cranial nerve examination was unremarkable. Computed tomography of the cervical spine demonstrated complete spondyloptosis at C4-5. The patient was immediately placed in cervical traction and taken to the operating room for open reduction of the fracture dislocation, decompression of the spinal cord, and stabilization with an interbody graft and cervical plate. Preoperative cervical traction was successful in only partial reduction of the fracture dislocation. Open reduction was achieved with exposure of the C-4 and C-5 bodies and sequential distraction. After anatomical alignment was achieved, an interbody graft was placed and a cervical plate secured. A subsequent decline in the patient\u27s level of consciousness prompted CT of the head, which showed evidence of a basilar artery thrombosis. A CT angiographic study demonstrated patency of the vertebral arteries, but a mid-basilar artery thrombosis. The patient progressed to brain death 24 hours after reduction of the fracture dislocation. The degree of contortion of the vertebral arteries in cervical spondyloptosis in the upper cervical spine may result in stasis of flow with subsequent formation of thrombus or intimal injury. After anatomical reduction, restoration of flow within the vertebral arteries may mobilize the thrombus or propagate an intimal dissection and result in subsequent embolic events. Endovascular evaluation may be warranted immediately after anatomical reduction of a high cervical spondyloptosis for evaluation of the vertebral arteries and possible thrombus dissolution or retrieval

Progressive vertebral body osteolysis after cervical disc arthroplasty.

STUDY DESIGN: Case report. OBJECTIVE: To review the management of a patient with progressive osteolysis of the vertebral body after undergoing cervical arthroplasty for management of a refractory radiculopathy. SUMMARY OF BACKGROUND DATA: Since the Food and Drug Administration\u27s (FDA) approval of cervical arthroplasty devices in 2007, many surgeons have incorporated this technology into clinical practice. As arthroplasty becomes more widespread, complications unique to this technology are inevitable. To date, only a limited number of complications have been reported in the literature suggesting the safety of this device. To the authors\u27 knowledge, this report represents the first complication of osteolysis from a keel based arthroplasty device. METHODS: A 30-year-old man underwent an uneventful C5-C6 total disc arthroplasty with initial benefit. Progressively worsening neck pain prompted repeat imaging at 9 and 15 months, which showed a progressive osteolytic process in the vicinity of the keel of the superior alloy endplate. This necessitated exploration of the surgical site, explantation of the implant and conversion of the disc arthroplasty to an arthrodesis. RESULTS: Examination of the osteolytic area did not reveal any gross abnormalities. Testing of the device by the manufacturer did not reveal any defects. A comprehensive infectious workup was negative. The osteolytic process halted after the explantation of the device. A bony arthrodesis was achieved at 6 months and the patient remains symptom free 29 months after the initial procedure and 14 months after the revision. CONCLUSION: This report illustrates an exceptional case of a progressive osteolysis with a keel based arthroplasty device. An immune mediated osteolytic process appears to be a plausible explanation for the clinical symptoms and radiographic progression seen in this case. Given the years of use of the ProDisc-C since its FDA approval in 2007, complications with this device are rare. This represents the first reported case of osteolysis from such an implant

Arthroscopic techniques in minimally invasive spine surgery: closure of the lumbar fascia: surgical technique.

BACKGROUND: The constrained working area in minimally invasive exposures of the spine may limit the capacity to effectively close the lumbar fascia, especially in patients with elevated body mass indexes. The working channel in these cases may have a diameter as narrow as 14 mm and a length up to 9 cm. Under these circumstances, the use of a conventional needle driver and a curved needle becomes suboptimal for closures of the fascia. OBJECTIVE: To demonstrate the utility of an arthroscopic suture passer for closure of the lumbar fascia in such approaches. METHODS: A flexible suture passer, typically used in arthroscopic rotator cuff repair surgery, was used through a minimally invasive portal for fascial closure after minimally invasive lumbar spine procedures. RESULTS: The use of an arthroscopic suture passer precludes the need for rotation of a curved needle in a constrained working area. Deploying a nitinol needle through an arc delivers the suture through the fascia, thereby facilitating closure. Satisfactory lumbar fascia closures were achieved in 18 patients with elevated body mass indexes. CONCLUSION: Application of existing technology in other surgical specialties may address the shortcomings of current techniques in minimally invasive approaches to the spine. The use of a flexible arthroscopic suture passer is one example in which current technology in one discipline may be applied to minimally invasive approaches. Increasing the awareness of techniques and instruments in other surgical disciplines may expand the armamentarium of the minimally invasive spine surgeon