Failure in Adult Spinal Deformity Surgery: A Comprehensive Review of Current Rates, Mechanisms, and Prevention Strategies.

STUDY DESIGN: Literature review. OBJECTIVE: The aim of this review is to summarize recent literature on adult spinal deformity (ASD) treatment failure as well as prevention strategies for these failure modes. SUMMARY OF BACKGROUND DATA: There is substantial evidence that ASD surgery can provide significant clinical benefits to patients. The volume of ASD surgery is increasing, and significantly more complex procedures are being performed, especially in the aging population with multiple comorbidities. Although there is potential for significant improvements in pain and disability with ASD surgery, these procedures continue to be associated with major complications and even outright failure. METHODS: A systematic search of the PubMed database was performed for articles relevant to failure after ASD surgery. Institutional review board approval was not needed. RESULTS: Failure and the potential need for revision surgery generally fall into 1 of 4 well-defined phenotypes: clinical failure, radiographic failure, the need for reoperation, and lack of cost-effectiveness. Revision surgery rates remain relatively high, challenging the overall cost-effectiveness of these procedures. CONCLUSION: By consolidating the key evidence regarding failure, further research and innovation may be stimulated with the goal of significantly improving the safety and cost-effectiveness of ASD surgery.

Results of the 2015 Scoliosis Research Society Survey on Single Versus Dual Attending Surgeon Approach for Adult Spinal Deformity Surgery.

STUDY DESIGN: An electronic survey administered to Scoliosis Research Society (SRS) membership. OBJECTIVE: To characterize surgeon practices and views regarding the use of two attending surgeons for adult spinal deformity (ASD) surgery. SUMMARY OF BACKGROUND DATA: The use of two experienced attending surgeons can decrease the operative time, estimated blood loss, and perioperative complication rates. However, the current practice patterns for the use of two attending surgeons remains unknown. METHODS: An electronic, 27-question survey regarding single/dual attending surgeons was administered to the SRS membership. Determinants included: surgeon/practice demographics, assistant type/level of training, and questions regarding use of two attending surgeons. Overall reporting and comparisons between groups were made: US versus international, academic versus private practice, and experience <15 years versus >15 years. RESULTS: A total of 199 surgeons responded from 27 different countries. Overall and between the groups, the respondents significantly reported believing that two attending spine surgeons improves safety, decreases complications, and improves outcomes (P < 0.01). Approximately, 67.3% reported using a second attending ≤25% of the time (33.2% do not), and 24.1% use one ≥51% of the time (similar between groups); 51.1% that have a second attending feel it's limited by reimbursement and access concerns and 71.9% have difficulty getting the second attending reimbursed. 72.3% use a second attending for ALL of the following reasons (no difference between groups): "it's safer/reduces complications," "it decreases operative time," "it decreases blood loss," "it results in improved outcomes," "it's less work and stress for me." If reimbursement was equal/assured for a second attending, 67.5% would use one "more often" or "always." CONCLUSION: The respondents feel that having a second attending surgeon improves patient care, however most do not use one often. Reasons include reimbursement/access concerns and the majority would use one if reimbursement was equal and assured. Based on the current literature and these results, there is a need for working with third party payers to improve dual surgeon reimbursement rates in complex cases. LEVEL OF EVIDENCE: 5.

Strategic design for pediatric neurosurgery missions across the Western Hemisphere.

BACKGROUND: With growing interest in global health, surgeons have created outreach missions to improve health care disparities in less developed countries. These efforts are mainly episodic with visiting surgeons performing the operations and minimal investment in local surgeon education. To create real and durable advancement in surgical services in disciplines that require urgent patient care, such as pediatric neurosurgery, improving the surgical armamentarium of the local surgeons must be the priority. METHODS: We propose a strategic design for extending surgical education missions throughout the Western Hemisphere in order to transfer modern surgical skills to local neurosurgeons. A selection criteria and structure for targeted missions is a derivative of logistical and pedagogical lessons ascertained from previous missions by our teams in Peru and Ukraine. RESULTS: Outreach programs should be applied to hospitals in capital cities to serve as a central referral center for maximal impact with fiscal efficiency. The host country should fulfill several criteria, including demonstration of geopolitical stability in combination with lack of modern neurosurgical care and equipment. The mission strategy is outlined as three to four 1-week visits with an initial site evaluation to establish a relationship with the hospital administration and host surgeons. Each visit should be characterized by collaboration between visiting and host surgeons on increasingly complex cases, with progressive transfer of skills over time. CONCLUSION: A strategic approach for surgical outreach missions should be built on collaboration and camaraderie between visiting and local neurosurgeons, with the mutual objective of cost-effective targeted renovation of their surgical equipment and skill repertoire.

Pediatric neurosurgery outreach: sustainability appraisal of a targeted teaching model in Kiev, Ukraine.

PURPOSE: This study evaluates the efficacy of operative skill transfer in the context of targeted pediatric outreach missions completed in Kiev, Ukraine. In addition the ability to create sustainable surgical care improvement is investigated as an efficient method to improve global surgical care. METHODS: Three 1-week targeted neurosurgical missions were performed (2005-2007) to teach neuroendoscopy, which included donation of the necessary surgical equipment, so the host team can deliver newly acquired surgical skills to their citizens after the visiting mission team departs. The neuroendoscopy data for the 4 years after the final mission in 2007 was obtained. RESULTS: After performing pediatric neurosurgery missions in 2005-2007, with a focus on teaching neuroendoscopy, the host team demonstrated the sustainability of our educational efforts in the subsequent 4 years by performing cases independently for their citizens. Since the last targeted mission of 2007, neuroendoscopic procedures have continued to be performed by the trained host surgeons. In 2008, 33 cases were performed. In 2009 and 2010, 29 and 22 cases were completed, respectively. In 2011, local neurosurgeons accomplished 27 cases. To date, a total of 111 operations have been performed over the past 4 years independent of any visiting team, illustrating the sustainability of educational efforts of the missions in 2005-2007. CONCLUSIONS: Effective operative skill transfer to host neurosurgeons can be accomplished with limited international team visits using a targeted approach that minimizes expenditures on personnel and capital. With the priority being teaching of an operative technique, as opposed to perennially performing operations by a visiting mission team, sustainable surgical care was achieved and perpetuated after missions officially concluded.

Targeted neurosurgical outreach: 5-year follow-up of operative skill transfer and sustainable care in Lima, Peru.

PURPOSE: This study evaluates the efficacy of operative skill transfer in the context of targeted pediatric outreach missions. In addition, the ability to implement surgical care improvements that are sustainable is investigated. METHODS: Three 1-week targeted neurosurgical missions were performed (2004-2006) to teach neuroendoscopy, which included donation of the necessary equipment so newly acquired surgical skills could be performed by local neurosurgeons in between and after the departure of the mission team. After the targeted missions were completed, 5 years of neuroendoscopy case follow-up data were obtained. RESULTS: After performing pediatric neurosurgery missions in 2004-2006, with a focus on teaching neuroendoscopy, the host team demonstrated the sustainability of our didactic efforts in the subsequent 5 years by performing cases independently for their citizens. To date, a total of 196 operations have been performed in the past 5 years independent of any visiting team. CONCLUSIONS: Effective operative skill transfer to host neurosurgeons can be accomplished with limited international team visits utilizing a targeted approach that minimizes expenditures on personnel and capital. With the priority being teaching of an operative technique, as opposed to perennially performing operations by the mission team, sustainable surgical care was achieved after missions officially concluded.

Expandable titanium cages for thoracolumbar vertebral body replacement: initial clinical experience and review of the literature.

Reconstruction of the anterior and middle column after vertebrectomy is essential for restoring stability. Use of expandable implants is supported by an emerging body of literature. Newer expandable cages have some advantages over traditional mesh implants, structural allograft, and polyetheretherketone or carbon fiber cages. To determine the utility of an expandable titanium cage in spine reconstruction, we conducted a retrospective cohort study of patients who had undergone this reconstruction after single or multilevel thoracic and/or lumbar vertebrectomy. Here we report on our experience using expandable cages at 2 large academic medical centers. Outcome was based on both clinical and radiographic measures with cross-sectional analysis. Thirty-five patients were identified. Of these, 20 had undergone surgery for neoplasm, 8 for trauma, and 7 for infection. Mean follow-up was 31 months (range, 12 to 50 months). Early postoperative kyphosis correction, restoration of sagittal alignment at 12 months, and reduction in visual analog scale pain score were significant. There was no difference in Oswestry Disability Index or height restoration. Expandable intervertebral body strut grafts appear to be a safe and effective option in spine reconstruction after a vertebrectomy and should be considered a treatment option.

Posterior approach for thoracolumbar corpectomies with expandable cage placement and circumferential arthrodesis: a multicenter case series of 67 patients.

OBJECT: The purpose of this multicenter trial was to investigate the outcome and durability of a single-stage thoracolumbar corpectomy using expandable cages via a posterior approach. METHODS: The authors conducted a retrospective chart review of 67 consecutive patients who underwent single-stage thoracolumbar corpectomies with circumferential reconstruction for pathological, traumatic, and osteomyelitic pathologies. Circumferential reconstruction was accomplished using expandable cages along with posterior instrumentation and fusion. Correction of the sagittal deformity, the American Spinal Injury Association score, and complications were recorded. RESULTS: Single-stage thoracolumbar corpectomies resulted in an average sagittal deformity correction of 6.2° at a mean follow-period of 20.5 months. At the last follow-up, a fusion rate of 68% was observed for traumatic and osteomyelitic fractures. Approximately one-half of the patients remained neurologically stable. Improvement in neurological function occurred in 23 patients (38%), whereas 7 patients (11%) suffered from a decrease in lower-extremity motor function. The deterioration in neurological function was due to progression of metastatic disease in 5 patients. Five constructs (7%) failed-3 of which had been placed for traumatic fractures, 1 for a pathological fracture, and 1 for an osteomyelitic fracture. Other complications included epidural hematomas in 3 patients and pleural effusions in 2. CONCLUSIONS: Single-stage posterior corpectomy and circumferential reconstruction were performed at multiple centers with a consistent outcome over a wide range of pathologies. Correction of the sagittal deformity was sustained, and the neurological outcome was good in the majority of patients; however, 18% of acute traumatic fractures required revision of the construct.

Maria Auxiliadora Hospital in Lima, Peru as a model for neurosurgical outreach to international charity hospitals.

INTRODUCTION: A myriad of geopolitical and financial obstacles have kept modern neurosurgery from effectively reaching the citizens of the developing world. Targeted neurosurgical outreach by academic neurosurgeons to equip neurosurgical operating theaters and train local neurosurgeons is one method to efficiently and cost effectively improve sustainable care provided by international charity hospitals. The International Neurosurgical Children's Association (INCA) effectively improved the available neurosurgical care in the Maria Auxiliadora Hospital of Lima, Peru through the advancement of local specialist education and training. METHODS: Neurosurgical equipment and training were provided for the local neurosurgeons by a mission team from the University of California at San Diego. RESULTS: At the end of 3 years, with one intensive week trip per year, the host neurosurgeons were proficiently and independently applying microsurgical techniques to previously performed operations, and performing newly learned operations such as neuroendoscopy and minimally invasive neurosurgery. CONCLUSION: Our experiences may serve as a successful template for the execution of other small scale, sustainable neurosurgery missions worldwide.

En bloc sacrectomy and reconstruction: technique modification for pelvic fixation.

BACKGROUND: When the management of sacral tumors requires partial or complete sacrectomy, the spinopelvic apparatus must be reconstructed. This is a challenging and infrequently performed operation, and as such, many spine surgeons are unfamiliar with techniques available to carry out these procedures. CASE DESCRIPTION: A 34-year-old man presented with severe low back pain, mild left ankle dorsiflexion weakness, and left S1 paresthesias. Imaging revealed a large sacral mass extending into the L5/S1 and S1/S2 neural foramina as well as the presacral visceral and vascular structures. Needle biopsy of this mass demonstrated a low-grade chondrosarcoma. A 2-stage anterior/posterior en bloc sacrectomy with a novel modification of the Galveston L-rod pelvic ring reconstruction was carried out. Our modification takes advantage of new materials and implant technology to offer another alternative in reconstruction of the spinopelvic junction. CONCLUSION: Understanding the anatomy and biomechanics of the spinopelvic apparatus and the lumbosacral junction, as well as having a familiarity with the various techniques available for carrying out sacrectomy and pelvic ring reconstruction, will enable the spine surgeon to effectively manage sacral tumors.

Patient satisfaction and radiographic outcomes after lumbar spinal fusion without iliac crest bone graft or transverse process fusion.

Iliac crest bone graft (ICBG) remains the gold standard for promoting bony fusion of the spine. However, harvest-site infection and pain are two of the most significant drawbacks of using iliac crest autograft in spinal fusion procedures. The rationale for its continued use, despite these drawbacks, has been based on the relatively higher rate of fusion reported in the literature. Therefore, the objective of this study was to determine whether modern allograft and fusion-promoting materials combined with local bone graft results in acceptable fusion rates and patient satisfaction. We retrospectively reviewed the clinical, surgical, and radiographic records of 200 consecutive patients with symptomatic degenerative diseases of the lumbar spine who underwent non-revision fusion using local bone graft combined with recombinant human bone morphogenetic protein (rhBMP)-2 with or without allograft. Rates of radiographic fusion and patient satisfaction were analyzed at discharge, 6 months, and 12 months, and every year thereafter. Mean follow-up was 32 months. Fusion was performed across an average of 2.5 levels and the overall fusion rate was 97%. In patients undergoing posterior fixation only there was a 5% incidence of pseudarthrosis, while the incidence was only 0.5% for patients undergoing circumferential fixation. Overall patient satisfaction at discharge was good to excellent in over 90% of patients and did not significantly change at the 6 month, 12 month and 24 month follow-up. In conclusion, there is no significant difference in rates of spinal fusion using laminectomy bone autograft combined with rhBMP-2 with or without allograft, compared to historical controls using ICBG. Fusion rates may be further improved with the use of circumferential fixation. Patient satisfaction remained high and might be because the morbidity associated with harvesting ICBG was avoided, as was the additional muscle dissection required for the fusion of lateral transverse processes.

Relaxation of forces needed to distract cervical vertebrae after discectomy: a biomechanical study.

STUDY DESIGN: In vitro and in vivo biomechanical stress measurements are made of the intervertebral disc segment distraction force during anterior cervical discectomy. OBJECTIVE: The purpose of this study is to determine the short-term force relaxation of the native intervertebral disc segment and to determine the short-term force relaxation of the segment after removal of the intervertebral disc, as is commonly performed in anterior cervical discectomy with fusion and arthroplasty. SUMMARY OF BACKGROUND DATA: No published data examine the issue of intraoperative distraction force of the cervical intervertebral disc segment. This is a novel research in this area. METHODS: In vitro and in vivo studies under institutional review board approval were performed to determine the mechanical behavior of the normal and diseased cervical functional spinal unit. Seven in vitro and 11 in vivo spines were studied. Strain measurements between distracting Caspar-type pins were made before, at various points during, and after discectomy to assess how removal of the disc and other spinal components affects the force-displacement behavior of the spinal unit. RESULTS: The in vitro data show progressive reduction in force needed for distraction after discectomy and uncovertebral joint resection. Greatest reduction is noted after discectomy. The in vivo data indicate that, on average, the cervical functional spinal unit requires 20 N less force to achieve the same degree of distraction after removal of the intervertebral disc. CONCLUSIONS: A sharp reduction in the strain across the intervertebral space occurs after distraction. The removal of the cervical intervertebral disc significantly reduces the viscoelastic response of the cervical motion segment. The long-term force used to stabilize intervertebral grafts or implants is less than what is achieved at the time of distraction. The exact magnitude of the resultant force on graft or device at a given distraction force is unknown and would depend also upon fit.

Multilevel lateral extra-cavitary corpectomy and reconstruction for non-contiguous metastatic lesions to the spine: case report and literature review.

In patients with metastatic disease to their spine and compromise of neurologic function, the challenge is to accomplish decompression of the neural elements and maintain mechanical stability but limit the risk and morbidity to the patient. In this case report the lateral extracavitary approach is employed to accomplish these tasks through a single approach in a patient with multiple non-contiguous sites of dorsal as well as ventral cord compression.

Perioperative complications and clinical outcomes of multilevel circumferential lumbar spinal fusion in the elderly.

Combined anterior-posterior lumbar fusion across multiple levels is thought to be associated with increased perioperative morbidity and worse clinical outcomes when performed in elderly patients. We conducted a retrospective review of the medical, surgical, and radiological records of 73 patients who underwent multilevel anterior lumbar interbody fusion (ALIF) with posterolateral lumbar fusion with instrumentation for symptomatic lumbar degenerative disc disease. Mean follow-up was 19 months. Thirty patients were at least 65 years old and 43 patients were younger. There were no significant differences in the number of levels fused, operative time, mean length of hospital stay or perioperative complication rates in either group. Similarly, there were no statistically significant differences in the improvement in back pain or in the rates of fusion between the groups at last follow-up. Perioperative events, intermediate-term clinical outcomes, and fusion rates after multilevel 360-degree lumbar fusion in the elderly are comparable to those of younger patients.

Long-term biomechanical stability and clinical improvement after extended multilevel corpectomy and circumferential reconstruction of the cervical spine using titanium mesh cages.

STUDY DESIGN: Retrospective review of clinical case series. OBJECTIVE: We present our experience with extended (> or =3 levels) anterior cervical corpectomy (EACC) and reconstruction. SUMMARY OF BACKGROUND DATA: Multilevel cervical corpectomy has traditionally been associated with increased graft-related complications and worse clinical outcomes compared with single-level procedures. Data specifically regarding corpectomies across 3 or more levels remains limited. METHODS: Retrospective review of data on 20 patients who underwent anterior cervical corpectomies with titanium mesh cage reconstruction and supplemental posterolateral fixation across 3 or more levels of the cervical spine. Anteroposterior/lateral plain films were used to determine sagittal balance and cage subsidence. Fusion was defined as the lack of motion on flexion-extension radiographs. Patients underwent preoperative and postoperative clinical assessment using visual analog scores and Nurick grading. RESULTS: Surgery was performed for spondylotic myelopathy in 15 patients, osteomyelitis in 4, and fracture in 1. Corpectomies were performed across an average of 3.4 levels. Average follow-up was 33 months. Local autograft was used in all cases except osteomyelitis, where allograft was used instead. Sagittal balance was improved or maintained in all patients and was not related to number of corpectomy levels. An average of 30.2 degrees of kyphosis correction was achieved in 9 patients. All patients demonstrated radiographic evidence of fusion without significant cage subsidence and no cases of instrumentation failure. Improvement in pain and functional scores occurred in all cases. CONCLUSIONS: Circumferential reconstruction using titanium mesh cages after EACC can provide appropriate, biomechanically stable fixation and allows for significant correction of preexisting kyphosis. Supplemental posterior instrumentation may limit delayed cage subsidence and loss of sagittal balance after this procedure. EACC and circumferential reconstruction seems to be an effective treatment for symptomatic degenerative, traumatic, or infectious pathology involving 3 or more levels of the anterior cervical spine.

Stem cell-mediated regeneration of the intervertebral disc: cellular and molecular challenge.

Regenerative medicine and stem cells hold great promise for intervertebral disc (IVD) disease. The therapeutic implications of utilizing stem cells to repair degenerated discs and treat back pain are highly anticipated by both the clinical and scientific communities. Although the avascular environment of the IVD poses a challenge for stem cell-mediated regeneration, neuroprogenitor cells have been discovered within degenerated discs, allowing scientists to revisit the hostile environment of the IVD as a target for stem cell therapy. Issues now under investigation include the timing of cell delivery and manipulation of stem cells to make them more efficient and adaptive in the IVD niche. This review covers the mechanisms underlying disc degeneration as well as the molecular and cellular challenges involved in directing stem cells to the desired cell type for intradiscal transplantation.

Stabilization of the atlantoaxial complex via C-1 lateral mass and C-2 pedicle screw fixation in a multicenter clinical experience in 102 patients: modification of the Harms and Goel techniques.

OBJECT: Stabilization of the atlantoaxial complex has proven to be very challenging. Because of the high mobility of the C1-2 motion segment, fusion rates at this level have been substantially lower than those at the subaxial spine. The set of potential surgical interventions is limited by the anatomy of this region. In 2001 Jürgen Harms described a novel technique for individual fixation of the C-1 lateral mass and the C-2 pedicle by using polyaxial screws and rods. This method has been shown to confer excellent stability in biomechanical studies. Cadaveric and radiographic analyses have indicated that it is safe with respect to osseous and vascular anatomy. Clinical outcome studies and fusion rates have been limited to small case series thus far. The authors reviewed the multicenter experience with 102 patients undergoing C1-2 fusion via the polyaxial screw/rod technique. They also describe a modification to the Harms technique. METHODS: One hundred two patients (60 female and 42 male) with an average age of 62 years were included in this analysis. The average follow-up was 16.4 months. Indications for surgery were instability at the C1-2 level, and a chronic Type II odontoid fracture was the most frequent underlying cause. All patients had evidence of instability on flexion and extension studies. All underwent posterior C-1 lateral mass to C-2 pedicle or pars screw fixation, according to the method of Harms. Thirty-nine patients also underwent distraction and placement of an allograft spacer into the C1-2 joint, the authors' modification of the Harms technique. None of the patients had supplemental sublaminar wiring. RESULTS: All but 2 patients with at least a 12-month follow-up had radiographic evidence of fusion or lack of motion on flexion and extension films. All patients with an allograft spacer demonstrated bridging bone across the joint space on plain x-ray films and computed tomography. The C-2 root was sacrificed bilaterally in all patients. A postoperative wound infection developed in 4 patients and was treated conservatively with antibiotics and local wound care. One patient required surgical debridement of the wound. No patient suffered a neurological injury. Unfavorable anatomy precluded the use of C-2 pedicle screws in 23 patients, and thus, they underwent placement of pars screws instead. CONCLUSIONS: Fusion of C1-2 according to the Harms technique is a safe and effective treatment modality. It is suitable for a wide variety of fracture patterns, congenital abnormalities, or other causes of atlantoaxial instability. Modification of the Harms technique with distraction and placement of an allograft spacer in the joint space may restore C1-2 height and enhance radiographic detection of fusion by demonstrating a graft-bone interface on plain x-ray films, which is easier to visualize than the C1-2 joint.

Two-level total en bloc lumbar spondylectomy with dural resection for metastatic renal cell carcinoma.

Only five reports of multilevel spondylectomy for tumor have been reported in the literature, mostly in the thoracic spine. We report a successful two-level spondylectomy with en bloc dural resection in a patient with metastatic renal carcinoma to the L3 and L4 vertebrae.

Partial spondylectomy: modification for lateralized malignant spinal column tumors of the cervical or lumbosacral spine.

Total en bloc spondylectomy is a useful technique in treating primary and secondary spinal malignancies, but requires extensive instrumentation to achieve difficult fusions, and requires extensive exposure of neurovascular structures that poses additional risk of nerve root and vascular injury. More limited resections may reduce these risks, especially in the cervical or lumbosacral spine. We report a technique used in two patients with lateralized primary vertebral tumors of the cervical or lumbosacral spine where tumor removal was achieved through a partial spondylectomy. The advantages of a partial spondylectomy included: (i) avoidance of injuring contralateral neurovascular structures during exposure; and (ii) supplementation of instrumentation by additional fixation at the level of spondylectomy. Partial spondylectomy can be an alternative to total en bloc spondylectomy in properly selected patients with lateralized encapsulated malignant spinal tumors and may be performed in the cervical or lumbosacral spinal regions.

Stand-alone anterior lumbar discectomy and fusion with plate: initial experience.

BACKGROUND: The stability of the lumbar spine after ALIF with lateral plate fixation and/or posterior fixation has previously been investigated; however, stand-alone ALDF with plate has not. Previous clinical studies have demonstrated poor fusion rates with stand-alone anterior interbody fusion in the absence of posterior instrumentation. We review our initial experience with stand-alone ALDF with segmental plate fixation for degenerative disc disease of the lumbar spine and compare these results with our experience with traditional ALIF and supplemental posterior instrumentation. METHODS: Forty-nine patients treated at the University of California, San Francisco between 2002 and 2005 were included in this analysis. The study was retrospective in nature. All patients presented with discogram-positive back pain and had failed conservative treatment. Twenty-four patients underwent ALDF with plate, and 25 underwent ALIF with posterior instrumentation. Patients underwent flexion/extension imaging at 6 weeks, 3 months, 6 months, and 1 year postoperatively. All patients completed ODI and VAS questionnaires at 3 months, 6 months, and 1 year postoperatively. RESULTS: Average follow-up was 11.6 and 21.7 months in the ALDF with plate and ALIF with instrumentation groups, respectively. All patients demonstrated radiographic evidence of fusion at last follow-up. None developed instability at the fusion level, and none developed hardware failure (plate back-out, screw lucency, etc). Average subsidence at 6 months postoperatively was 2.2 and 2.5 mm, respectively. The VAS and ODI scores are presented in Tables 3 and 4. CONCLUSIONS: Preliminary results of stand-alone ALDF with plate suggest it may be safe and effective for the surgical treatment of patients with degenerative disc disease of the lumbar spine. Long-term follow-up is clearly needed. Subsidence is diminished with ALDF and plating compared with ALIF with posterior instrumentation. It is unclear at this time which subset of patients may ultimately require posterior hardware supplementation, but those with circumferential stenosis or severe facet disease are not ideal candidates for ALDF with plate. For some patients in whom lumbar arthroplasty is not indicated, or as a salvage procedure, ALDF with plate may be a satisfactory alternative and may eliminate the need for a supplemental posterior procedure.

Bioabsorbable anterior cervical plating: initial multicenter clinical and radiographic experience.

STUDY DESIGN: Prospective clinical trial. OBJECTIVE: The authors present their initial multicenter experience in the surgical management of 1-level degenerative disc disease of the cervical spine with anterior cervical discectomy and fusions (ACDF) using a bioabsorbable polymer plate. SUMMARY OF BACKGROUND DATA: The introduction of a radiolucent bioabsorbable polymer plate and screws for ACDF presents a novel opportunity to gain the some of the potential added benefit of stabilization with internal immobilization while possibly reducing some of the long-term complications and imaging artifacts associated with titanium instrumentation. We prospectively analyze 52 patients who were treated at 6 different institutions across the United States with bioabsorbable polymer plate and screws for ACDF surgery. METHODS: Patients were prospectively enrolled. A retrospective review of patients' charts and imaging was performed to determine clinical and radiographic outcome following anterior cervical spine surgery. Specifically, the authors looked at need for additional surgeries, local reaction to bioabsorbable polymer, fusion rate, and complications. Surgeries involved the C4-C5, C5-C6, C6-C7, and/or C7-T1 levels. Cadaveric bone was used in 42 patients, polyetheretherketone (PEEK) cages in 6 patients, and iliac crest autograft in 4 patients. The patients were observed for an average of 13.3 months. RESULTS: Radiographic fusion was achieved in 98.1% (51 of 52 patients) of the cases at 6 months. One patient has evidence of nonunion on flexion-extension imaging but remains asymptomatic. A different patient developed mild kyphosis after surgery and had persistence of radicular symptoms but refused further surgery. There were no clinical signs or symptoms of reaction to the bioabsorbable material. CONCLUSIONS: The rates of fusion following single-level ACDF with internal fixation using bioabsorbable polymer plate and screws in this study match those previously reported in the literature with metallic implants and are superior to noninstrumented fusions. Preliminary results suggest that this newly available technology for anterior fusion may be as effective as traditional titanium plating systems in single-level disease. The bioabsorbable material appears to be well tolerated by patients. A larger, randomized, controlled study is necessary to bring the results to statistical significance.