Anterior Cervical Foraminotomy for Radiculopathy After Cervical Artificial Disc Replacement: Technique Description and Case Report.

BACKGROUND: Patients may occasionally have persistent or recurrent radicular symptoms after cervical artificial disc replacement (ADR) for cervical spondylotic radiculopathy. We describe our approach using anterior cervical foraminotomy (ACF) to provide symptom relief in such patients without the need to convert to a fusion or remove the ADR implant. METHODS: Our operative technique for ACF after cervical ADR begins by starting at the lateral edge of the ADR at the superior end plate of the inferior vertebral body. The ipsilateral uncovertebral joint is drilled with a combination of a high-speed burr and diamond-coated burr to minimize the risk of injury to the vertebral artery. The neuroforamen is entered after drilling through the posterior aspect of the uncinate process. The exiting cervical nerve root should be directly visualized, and a Kerrison rongeur may be used to trace along the nerve root laterally to remove any remaining uncinate osteophyte or process. We queried our internal database for patients with recurrent or new radicular pain following cervical ADR who underwent ACF. Clinical characteristics and outcomes were reported. RESULTS: Five patients with recurrent radicular symptoms after ADR were reviewed. Two ACFs were performed at C5-6, and 2 were performed at C6-7. Four patients developed ipsilateral recurrent radicular symptoms, and only 1 patient developed contralateral new radicular symptoms. Three patients reported complete resolution of their new or recurrent radicular symptoms following ACF, and 2 patients reported only partial resolution. No patients required conversion to a fusion. CONCLUSIONS: In patients with recurrent symptoms of cervical spondylotic radiculopathy following ADR, ACF with uncovertebral joint resection can be used to provide direct foraminal decompression without the need for implant removal. This approach also preserves motion at the affected level, preserves cervical spinal stability, and prevents the need for spinal fusion. CLINICAL RELEVANCE: Patients with persistent or recurrent radicular symptoms after cervical ADR may achieve resolution of symptoms through a modified ACF technique.

Prospective, randomized multicenter study of cervical arthroplasty versus anterior cervical discectomy and fusion: 5-year results with a metal-on-metal artificial disc.

OBJECTIVE Seven cervical total disc replacement (TDR) devices have received FDA approval since 2006. These devices represent a heterogeneous assortment of implants made from various biomaterials with different biomechanical properties. The majority of these devices are composed of metallic endplates with a polymer core. In this prospective, randomized multicenter study, the authors evaluate the safety and efficacy of a metal-on-metal (MoM) TDR (Kineflex|C) versus anterior cervical discectomy and fusion (ACDF) in the treatment of single-level spondylosis with radiculopathy through a long-term (5-year) follow-up. METHODS An FDA-regulated investigational device exemption (IDE) pivotal trial was conducted at 21 centers across the United States. Standard validated outcome measures including the Neck Disability Index (NDI) and visual analog scale (VAS) for assessing pain were used. Patients were randomized to undergo TDR using the Kineflex|C cervical artificial disc or anterior cervical fusion using structural allograft and an anterior plate. Patients were evaluated preoperatively and at 6 weeks and 3, 6, 12, 24, 36, 48, and 60 months after surgery. Serum ion analysis was performed on a subset of patients randomized to receive the MoM TDR. RESULTS A total of 269 patients were enrolled and randomly assigned to undergo either TDR (136 patients) or ACDF (133 patients). There were no significant differences between the TDR and ACDF groups in terms of operative time, blood loss, or length of hospital stay. In both groups, the mean NDI scores improved significantly by 6 weeks after surgery and remained significantly improved throughout the 60-month follow-up (both p < 0.01). Similarly, VAS pain scores improved significantly by 6 weeks and remained significantly improved through the 60-month follow-up (both p < 0.01). There were no significant changes in outcomes between the 24- and 60-month follow-ups in either group. Range of motion in the TDR group decreased at 3 months but was significantly greater than the preoperative mean value at the 12- and 24-month follow-ups and remained significantly improved through the 60-month period. There were no significant differences between the 2 groups in terms of reoperation/revision surgery or device-/surgery-related adverse events. The serum ion analysis revealed cobalt and chromium levels significantly lower than the levels that merit monitoring. CONCLUSIONS Cervical TDR with an MoM device is safe and efficacious at the 5-year follow-up. These results from a prospective randomized study support that Kineflex|C TDR as a viable alternative to ACDF in appropriately selected patients with cervical radiculopathy. Clinical trial registration no.: NCT00374413 (clinicaltrials.gov).

Use of Nanocrystalline Hydroxyapatite With Autologous BMA and Local Bone in the Lumbar Spine: A Retrospective CT Analysis of Posterolateral Fusion Results.

STUDY DESIGN: A retrospective, multicenter, medical record review and independent analysis of computed tomographic scans was performed in 46 patients to determine radiographic arthrodesis rates after 1-segment, 2-segment, or 3-segment instrumented posterolateral fusions (PLF) using autograft, bone marrow aspirate (BMA), and a nanocrystalline hydroxyapatite bone void filler (nHA). OBJECTIVE: To determine the radiographic arthrodesis rates after instrumented lumbar PLF using local autograft, BMA, and nHA. SUMMARY OF BACKGROUND DATA: The use of iliac crest autograft in posterolateral spine fusion carries real and significant risks. Many forms of nanocrystalline hydroxyapatite have been studied in various preclinical models, but no human studies have reviewed its efficacy as a bone graft supplement in PLF. METHODS: Posterolateral arthrodesis progression was documented approximately 12 months postoperatively using a computed tomographic scan and evaluated by an independent radiologist for the presence of bridging bone. One-year postoperative clinical outcomes were assessed using the PROLO score. RESULTS: Radiographically, 91% patients treated exhibited bilateral or unilateral posterolateral bridging bone. Ninety-four percent of the segments treated exhibited bilateral or unilateral posterolateral bridging bone, whereas 6% segments exhibited no posterolateral bridging bone on either side. A total of 93% individual sites treated exhibited posterolateral bridging bone. In 1-segment, 2-segment, and 3-segment arthrodesis, 88%, 93%, and 100%, respectively, of individual sites exhibited radiographic bridging bone. One-year postoperative PROLO scores for 77% patients were excellent or good. There were no complications related to the posterolateral graft mass and no symptomatic nonunions. CONCLUSIONS: The arthrodesis rates after instrumented lumbar fusion using local autograft mixed with BMA and the nHA is equivalent to the rates reported for iliac crest autograft in these indications, including stringent indications, such as 3-segment procedures. By approximately 12 months postoperatively, there was no significant difference in the rates of bridging bone between the 1-segment, 2-segment, and 3-segment procedures.

Evaluation of Decompression and Interlaminar Stabilization Compared with Decompression and Fusion for the Treatment of Lumbar Spinal Stenosis: 5-year Follow-up of a Prospective, Randomized, Controlled Trial.

INTRODUCTION: If nonoperative treatment for lumbar stenosis fails, surgery may be considered. This traditionally includes decompression often combined with fusion. Desire for less extensive surgery led to developing new techniques and implants, including an interlaminar device designed with the goal of providing segmental stability without fusion, following decompression. The purpose of this study was to investigate 5-year outcomes associated with an interlaminar device. METHODS: This prospective, randomized, controlled trial was conducted at 21 centers. Patients with moderate to severe lumbar stenosis at one or two contiguous levels and up to Grade I spondylolisthesis were randomized (2:1 ratio) to decompression and interlaminar stabilization (D+ILS; n=215) using the coflex(®) Interlaminar Stabilization(®) device (Paradigm Spine, LLC) or decompression and fusion with pedicle screws (D+PS; n=107). Clinical evaluations were made preoperatively and at 6 weeks and 3, 6, 12, 18, 24, 36, 48, and 60 months postoperatively. Overall Food and Drug Administration success criteria required that a patient meet 4 criteria: 1) >15 point improvement in Oswestry Disability Index (ODI) score; 2) no reoperation, revision, removal, or supplemental fixation; 3) no major device-related complication; and 4) no epidural steroid injection after surgery. RESULTS: At 5 years, 50.3% of D+ILS vs. 44% of D+PS patients (p>0.35) met the composite success criteria. Reoperation/revision rates were similar in the two groups (16.3% vs. 17.8%; p >0.90). Both groups had statistically significant improvement through 60 months in ODI scores with 80.6% of D+ILS patients and 73.2% of D+PS patients demonstrating >15 point improvement (p>0.30). VAS, SF-12, and ZCQ scores followed a similar pattern of maintained significant improvement throughout follow-up. On the SF-12 and ZCQ, D+ILS group scores were statistically significantly better during early follow-up compared to D+PS. In the D+ILS group, foraminal height, disc space height, and range of motion at the index level were maintained through 5 years. CONCLUSION: Both treatment groups achieved and maintained statistically significant improvements on multiple outcome assessments throughout 5-year follow-up. On some clinical measures, there were statistically significant differences during early follow-up favoring D+ILS. At no point were there significant differences favoring D+PS. Results of this 5-year follow-up study demonstrate that decompression and interlaminar stabilization with coflex is a viable alternative to traditional decompression and fusion in the treatment of patients with moderate to severe stenosis at one or two lumbar levels. LEVEL OF EVIDENCE AND ETHICAL STATEMENTS: This is a Level I study. Institutional approval was received at each of the sites participating in the trial. Each patient gave informed consent to participate in the trial.

Stand-alone interspinous spacer versus decompressive laminectomy for treatment of lumbar spinal stenosis.

OBJECTIVE: To compare the two-year clinical outcomes of a prospective, randomized controlled trial of an FDA-approved interspinous spacer with the compilation of published findings from 19 studies of decompressive laminectomy for the treatment of lumbar spinal stenosis. METHODS: Back and leg pain, Oswestry disability index (ODI), and Zurich Claudication Questionnaire (ZCQ) values were compared between spacer- and laminectomy-treated patients preoperatively and at 12 and 24 months. RESULTS: Percentage improvements between baseline and 24 months uniformly favored patients treated with the spacer for back pain (65% vs. 52%), leg pain (70% vs. 62%), ODI (51% vs. 47%) and ZCQ symptom severity (37% vs. 29%) and physical function (36% vs. 32%). CONCLUSION: Both treatments provide effective and durable symptom relief of claudicant symptoms. This stand-alone interspinous spacer offers the patient a minimally invasive option with less surgical risk.

Therapeutic sustainability and durability of coflex interlaminar stabilization after decompression for lumbar spinal stenosis: a four year assessment.

BACKGROUND: Approved treatment modalities for the surgical management of lumbar spinal stenosis encompass a variety of direct and indirect methods of decompression, though all have varying degrees of limitations and morbidity which potentially limit the efficacy and durability of the treatment. The coflex(®) interlaminar stabilization implant (Paradigm Spine, New York, NY), examined under a United States Food and Drug Administration (US FDA) Investigational Device Exemption (IDE) clinical trial, is shown to have durable outcomes when compared to posterolateral fusion in the setting of post-decompression stabilization for stenotic patients. Other clinical and radiographic parameters, more indicative of durability, were also evaluated. The data collected from these parameters were used to expand the FDA composite clinical success (CCS) endpoint; thus, creating a more stringent Therapeutic Sustainability Endpoint (TSE). The TSE allows more precise calculation of the durability of interlaminar stabilization (ILS) when compared to the fusion control group. METHODS: A retrospective analysis of data generated from a prospective, randomized, level-1 trial that was conducted at 21 US sites was carried out. Three hundred forty-four per-protocol subjects were enrolled and randomized to ILS or fusion after decompression for lumbar stenosis with up to grade 1 degenerative spondylolisthesis. Clinical, safety, and radiographic data were collected and analyzed in both groups. Four-year outcomes were assessed, and the TSE was calculated for both cohorts. The clinical and radiographic factors thought to be associated with therapeutic sustainability were added to the CCS endpoints which were used for premarket approval (PMA). RESULTS: Success rate, comprised of no second intervention and an ODI improvement of ≥ 15 points, was 57.6% of ILS and 46.7% of fusion patients (p = 0.095). Adding lack of fusion in the ILS cohort and successful fusion in the fusion cohort showed a CCS of 42.7% and 33.3%, respectively. Finally, adding adjacent level success to both cohorts and maintenance of foraminal height in the coflex cohort showed a CCS of 36.6% and 25.6%, respectively. With additional follow-up to five years in the U.S. PMA study, these trends are expected to continue to show the superior therapeutic sustainability of ILS compared to posterolateral fusion after decompression for spinal stenosis. CONCLUSION: There are clear differences in both therapeutic sustainability and intended clinical effect of ILS compared to posterolateral fusion with pedicle screw fixation after decompression for spinal stenosis. There are CCS differences between coflex and fusion cohorts noted at four years post-op similar to the trends revealed in the two year data used for PMA approval. When therapeutic sustainability outcomes are added to the CCS, ILS is proven to be a sustainable treatment for stabilization of the vertebral motion segment after decompression for lumbar spinal stenosis.

Facet-sparing decompression with a minimally invasive flexible microblade shaver: a prospective operative analysis.

STUDY DESIGN: This is a detailed description of a facet-sparing decompression technique and a prospective observational study of 59 subjects. OBJECTIVE: To describe a facet-sparing decompression technique, quantify operative parameters, adverse events, and anatomic changes following decompression with a flexible microblade shaving system. SUMMARY OF BACKGROUND DATA: Decompression in patients with lumbar spinal stenosis is a common surgical procedure. However, obtaining a thorough decompression while leaving enough tissue to avoid destabilization can be challenging. Decompression with a flexible, through-the-foramen system may mitigate some of these challenges. MATERIALS AND METHODS: Fifty-nine subjects diagnosed with lumbar spinal stenosis were recruited into this study. Subjects underwent decompression with a flexible, microblade decompression system at a total of 88 levels between L2 and S1. Subject demographics, details of the procedure, and operation, including adverse events were collected. Preoperative and postoperative computed tomography scans and plain radiographs were obtained from a subset of 12 subjects and quantitatively assessed for bone removal and preservation of stabilizing structures. RESULTS: Fifty-nine subjects had 88 levels treated, 51% single-level and 49% 2-level with L4-L5 being the most commonly decompressed level. Operative time, blood loss, and length of stay were similar to or less than that seen in the historical control. The system was successfully used for decompression in 95.8% of the attempted foramina. Three operative complications were reported, all dural tears (5.1%). These dural tears occurred before introduction of the flexible decompression system. Computed tomography scans from 12 subjects demonstrate access to the lateral recess and foramen with removal of <6% of the superior facet cross-sectional area. CONCLUSIONS: The flexible microblade shaving system provided thorough decompression with few intraoperative complications. Operative variables were favorable compared to the literature and radiographic decompression was achieved to a great extent while allowing for the preservation of the facet joints and midline structures.

Advances in the management of spinal cord and spinal column injuries.

Spinal cord injury (SCI) is a significant public problem, with recent data suggesting that over 1 million people in the U.S.A. alone are affected by paralysis resulting from SCI. Recent advances in prehospital care have improved survival as well as reduced incidence and severity of SCI following spine trauma. Furthermore, increased understanding of the secondary mechanisms of injury following SCI has provided improvements in critical care and acute management in patients suffering from SCI, thus limiting morbidity following injury. In addition, improved technology and biomechanical understanding of the mechanisms of spine trauma have allowed further advances in available techniques for spinal decompression and stabilization. In this chapter we review the most recent data and salient literature regarding SCI and address current controversies, including the use of pharmacological adjuncts in the setting of acute SCI. We will also attempt to provide a reader with basic understanding of the classifications of SCI and spinal column injury. Finally, we review advances in spinal column stabilization including improvements in instrumented fusion and minimally invasive surgery.

Facet-sparing lumbar decompression with a minimally invasive flexible MicroBlade Shaver® versus traditional decompression: quantitative radiographic assessment.

BACKGROUND: Laminectomy/laminotomy and foraminotomy are well established surgical techniques for treatment of symptomatic lumbar spinal stenosis. However, these procedures have significant limitations, including limited access to lateral and foraminal compression and postoperative instability. The purpose of this cadaver study was to compare bone, ligament, and soft tissue morphology following lumbar decompression using a minimally invasive MicroBlade Shaver® instrument versus hemilaminotomy with foraminotomy (HL). METHODS: The iO-Flex® system utilizes a flexible over-the-wire MicroBlade Shaver instrument designed for facet-sparing, minimally invasive "inside-out" decompression of the lumbar spine. Unilateral decompression was performed at 36 levels in nine human cadaver specimens, six with age-appropriate degenerative changes and three with radiographically confirmed multilevel stenosis. The iO-Flex system was utilized on alternating sides from L2/3 to L5/S1, and HL was performed on the opposite side at each level by the same investigator. Spinal canal, facet joint, lateral recess, and foraminal morphology were assessed using computed tomography. RESULTS: Similar increases in soft tissue canal area and decreases in ligamentum flavum area were noted in nondiseased specimens, although HL required removal of 83% more laminar area (P < 0.01) and 95% more bone resection, including the pars interarticularis and facet joints (P < 0.001), compared with the iO-Flex system. Similar increases in lateral recess diameter were noted in nondiseased specimens using each procedure. In stenotic specimens, the increase in lateral recess diameter was significantly (P = 0.02) greater following use of the iO-Flex system (43%) versus HL (7%). The iO-Flex system resulted in greater facet joint preservation in nondiseased and stenotic specimens. In stenotic specimens, the iO-Flex system resulted in a significantly greater increase in foraminal width compared with HL (24% versus 4%, P = 0.01), with facet joint preservation. CONCLUSION: The iO-Flex system resulted in significantly better decompression of the lateral recess and foraminal areas compared with HL, while preserving posterior spinal elements, including the facet joint.

Minimally invasive approaches to the cervical spine.

Minimally invasive approaches and operative techniques are becoming increasingly popular for the treatment of cervical spine disorders. Minimally invasive spine surgery attempts to decrease iatrogenic muscle injury, decrease pain, and speed postoperative recovery with the use of smaller incisions and specialized instruments. This article explains in detail minimally invasive approaches to the posterior spine, the techniques for posterior cervical foraminotomy and arthrodesis via lateral mass screw placement, and anterior cervical foraminotomy. Complications are also discussed. Additionally, illustrated cases are presented detailing the use of minimally invasive surgical techniques.

Cervical total disc replacement using a novel compressible prosthesis: Results from a prospective Food and Drug Administration-regulated feasibility study with 24-month follow-up.

BACKGROUND: Anterior cervical fusion, an established procedure to treat cervical radiculopathy, sacrifices the natural function of the disc, while placing increased stresses on adjacent spinal levels. In contrast, the cervical total disc replacement (cTDR) maintains motion and decreases adjacent-level stresses. The purpose of this study was to investigate the safety and effectiveness of a next-generation cTDR device in patients with symptomatic cervical radiculopathy. METHODS: This is a multicenter Food and Drug Administration-regulated feasibility study to evaluate safety and effectiveness of the M6-C Artificial Cervical Disc for the treatment of patients with symptomatic cervical radiculopathy at 1 or 2 levels from C3 to C7. Neck Disability Index (NDI), visual analog scales (VAS) assessing neck and arm pain, Short Form 36 Health Survey (SF-36), safety, and radiographic outcomes were assessed preoperatively, at 6 weeks and 3, 6, 12, and 24 months postoperatively. RESULTS: Thirty patients were enrolled at 3 clinical sites. Patients were implanted at either 1 or 2 levels. Mean NDI improved from 67.8 to 20.8 (P < .0001) at 24 months. Significant improvement was also observed through 24-month follow-up in neck and arm pain VAS (P < .0001) and in physical (P < .005) and mental component scores of the SF-36 at 3, 6, and 12 months (P < .008). There were no serious adverse events related to the device or procedure as adjudicated by an independent clinical events committee. Radiographically, disc space height increased more than 50% with a correlative increase in the postoperative disc angle. Range of motion decreased slightly from baseline during early follow-up but increased slightly and were maintained throughout the follow-up period. CONCLUSIONS: The M6-C cervical artificial disc represents a new generation of cTDR design. Results of this study found the M6-C device to produce positive clinical and radiographic outcomes similar to other cTDRs, warranting further investigation.

Prospective, randomized, multicenter study of cervical arthroplasty: 269 patients from the Kineflex|C artificial disc investigational device exemption study with a minimum 2-year follow-up: clinical article.

OBJECT: Cervical total disc replacement (CTDR) represents a relatively novel procedure intended to address some of the shortcomings associated with anterior cervical discectomy and fusion (ACDF) by preserving motion at the treated level. This prospective, randomized, multicenter study evaluates the safety and efficacy of a new metal-on-metal CTDR implant (Kineflex|C) by comparing it with ACDF in the treatment of single-level spondylosis with radiculopathy. METHODS: The study was a prospective, randomized US FDA Investigational Device Exemption (IDE) pivotal trial conducted at 21 centers across the US. The primary clinical outcome measures included the Neck Disability Index (NDI), visual analog scale (VAS) scores, and a composite measure of clinical success. Patients were randomized to CTDR using the Kineflex|C (SpinalMotion, Inc.) cervical artificial disc or ACDF using structural allograft and an anterior plate. RESULTS: A total of 269 patients were enrolled and randomly assigned to either CTDR (136 patients) or to ACDF (133 patients). There were no significant differences between the CTDR and ACDF groups when comparing operative time, blood loss, length of hospital stay, or the reoperation rate at the index level. The overall success rate was significantly greater in the CTDR group (85%) compared with the ACDF group (71%) (p = 0.05). In both groups, the mean NDI scores improved significantly by 6 weeks after surgery and remained significantly improved throughout the 24-month follow-up (p < 0.0001). Similarly, the VAS pain scores improved significantly by 6 weeks and remained significantly improved through the 24-month follow-up (p < 0.0001). The range of motion (ROM) in the CTDR group decreased at 3 months but was significantly greater than the preoperative mean at 12- and 24-month follow-up. The ROM in the ACDF group was significantly reduced by 3 months and remained so throughout the follow-up. Adjacent-level degeneration was also evaluated in both groups from preoperatively to 2-year follow-up and was classified as none, mild, moderate, or severe. Preoperatively, there were no significant differences between groups when evaluating the different levels of adjacent-level degeneration. At the 2-year follow-up, there were significantly more patients in the ACDF group with severe adjacent-level radiographic changes (p < 0.0001). However, there were no significant differences between groups in adjacent-level reoperation rate (7.6% for the Kineflex|C group and 6.1% for the ACDF group). CONCLUSIONS: Cervical total disc replacement allows for neural decompression and clinical results comparable to ACDF. Kineflex|C was associated with a significantly greater overall success rate than fusion while maintaining motion at the index level. Furthermore, there were significantly fewer Kineflex|C patients showing severe adjacent-level radiographic changes at the 2-year follow-up. These results from a prospective, randomized study support that Kineflex|C CTDR is a viable alternative to ACDF in select patients with cervical radiculopathy.

Technical advances in minimally invasive surgery: direct decompression for lumbar spinal stenosis.

STUDY DESIGN: Literature review, technique overview, prospective and retrospective data analysis. OBJECTIVE: To review current minimally invasive surgery (MIS) methods of decompression for lumbar spinal stenosis and present a decompression technique using a flexible microblade shaver system. SUMMARY OF BACKGROUND DATA: Several MIS decompression techniques for stenosis have been developed to minimize damage to soft tissues and reduce the amount of posterior element resection. Decompression using linearly configured instruments may not be able to adequately address stenosis in the neural foramen. A flexible microblade shaver system is able to traverse the foramen, removing bone and ligament, using a ventral to dorsal approach, rather than medial to lateral. This enables it to effectively decompress the lateral recess and neural foramen while sparing posterior structures. METHODS: Brief literature review of current MIS decompression techniques is presented. MIS decompression using a flexible microblade shaver system is described with 1 year outcomes from a small pilot study and a retrospective chart review at 2 centers. RESULTS: A small postmarket pilot study (n = 9) with 1 year results showed positive patient outcomes using Visual Analog Scale (decrease by 73%), Oswestry Disability Index(50% improvement), Zurich Claudication Questionnaire physical function and symptom severity (improved by 72% and 31%, respectively), and Short-Form 36 (SF-36) Physical Component Score (36% improvement). Sixty-seven patients from a retrospective chart review at 2 centers had an average of 2 levels per patient decompressed using a flexible microblade shaver system. No patient has returned for additional surgery and there have been no cases of neurologic impairment. CONCLUSION: Current decompression techniques may result in inadequate decompression of the neural foramen or excessive resection of the facet joint. MIS decompression using a flexible microblade shaver system represents a way to perform an effective, facet-preserving decompression for patients with lumbar spinal stenosis.

Appropriate selection of patients with lumbar spinal stenosis for interspinous process decompression with the X STOP device.

With the aging of the population, the number of patients suffering from progressive lumbar spinal stenosis with symptomatic neurogenic intermittent claudication is projected to increase. Unfortunately, these patients are limited to a choice between nonsurgical conservative care and more invasive decompressive surgical procedures such as laminectomy with or without fusion. The X STOP interspinous process decompression system is a commercially available device that provides a minimally invasive alternative treatment, an intermediate option within the continuum of care for these patients. The X STOP is appropriate for patients with moderately severe functional impairment whose symptoms are exacerbated in extension and relieved in flexion. Implanted between the spinous processes without disrupting the normal anatomical structures, the X STOP limits narrowing of the spinal canal and neural foramina by reducing extension at the symptomatic level(s). In this report the author details the approved indications for use of the X STOP and discusses several illustrative cases.

Adverse swelling associated with use of rh-BMP-2 in anterior cervical discectomy and fusion: a case study.

BACKGROUND CONTEXT: The use of recombinant bone morphogenetic protein-2 (rh-BMP-2) is effective in augmenting lumbar spinal fusions. A safe, effective dosage of rh-BMP-2 in the cervical spine has yet to be determined. Use of rh-BMP-2 is currently being evaluated and is only indicated for use in the cervical spine on Investigational Device Exempt cases. PURPOSE: To present a potentially serious adverse event that may occur when using rh-BMP-2 in cervical spine surgery. STUDY DESIGN: An emergent sequence of events including physical examination, radiographic studies, intubation, and surgical exploration were performed upon arrival to the emergency department. METHODS: We report a case of a 54-year-old male patient presenting with neck swelling and difficulty swallowing 5 days after anterior cervical discectomy and fusion (ACDF) using rh-BMP-2. RESULTS: The patient was found to have massive neck swelling including the pharyngeal tissue. The patient was admitted to the intensive care unit where parenteral steroids were administered for 24 hours during monitored intubation. The patient was extubated on the second hospital day and discharged home on the fourth hospital day after swelling subsided. CONCLUSIONS: Caution should be exercised with rh-BMP-2 use in ACDF surgery as the correct dose and technique for application is not yet determined. Respiratory distress and dysphagia may result secondary to rh-BMP-2 induced anterior neck swelling.

Nerve reconstruction in lumbosacral plexopathy. Case report and review of the literature.

Neurological injury to the lumbosacral plexus associated with pelvic and sacral fractures has traditionally been treated conservatively, despite significant and often debilitating functional deficits of the lower extremities. The authors report a case of reconstruction of the lumbosacral plexus, including nerve grafting to restore lower-extremity function caused by severe trauma to the pelvis. A 16-year-old boy sustained pelvic and sacral fractures in a motor vehicle accident. After stabilization of his orthopedic injuries, he suffered from paresis of his right gluteal and hamstring muscles and had no motor or sensory function below his knee. Two months later, he underwent reconstruction of his lumbosacral plexus performed using a nerve graft from his L-5 and S-1 nerve roots proximal to the inferior gluteal nerve and distal to a branch to the hamstring muscles. After another 2 months, his recovering saphenous nerve was transferred to the sensory component of the posterior tibial nerve by using cabled sural nerve grafts to restore sensation to the sole of his foot. After 2.5 years, he experienced reinnervation of his gluteal and hamstring muscles and could perceive vibration on the sole of his foot. With the assistance of a foot-drop splint, the patient ambulates well and is able to ski. Operative details and the relevant literature are reviewed.

Techniques for aspirating bone marrow for use in spinal surgery.

OBJECTIVE: The osteogenicity of bone marrow has been well documented in the literature. The use of bone marrow as a source of osteoprogenitor cells for spinal fusion surgery is increasing. Improper aspiration technique can lead to dilution of bone marrow and a subsequent reduction in osteoprogenitor cells. Therefore, correct aspiration technique is imperative to the successful use of bone marrow with various grafting combinations. METHODS: The authors describe techniques for aspirating bone marrow from the anterior and posterior iliac crest, as well as vertebral body aspiration. The use of selective cell retention to increase the number of osteoprogenitor cells populating a graft is also described. RESULTS: Complications from bone marrow aspiration can occur, but the incidence is rare. CONCLUSION: Clinical studies currently under way will answer the question of bone marrow efficacy in spinal fusion surgery.

The changing role for neurosurgeons and the treatment of spinal deformity.

Spinal deformity has classically and historically been studied by those in the discipline of orthopedic surgery. This may be attributable to the orthopedic interventionalists' experience with osseous fixation for long-bone and other skeletal fractures. Neurosurgeons have maintained a long-standing interest in complex cervical spinal disorders, and their interest in the larger field of complex spinal deformity has been expanding. An understanding of spinal deformity disorders, biomechanics, bone biology, and metallurgy is necessary before clinical, teaching, and research activities can be undertaken within neurosurgery. The authors describe basic and advanced concepts of spinal deformity management with cases to illustrate teaching points.

Clinical outcomes and complications associated with pedicle screw fixation-augmented lumbar interbody fusion.

OBJECT: The authors conducted a prospective study to evaluate the clinical and radiological outcomes and complications associated with uni- and bilateral transforaminal lumbar interbody fusion (TLIF) performed using carbon fiber Brantigan I/F Cages and pedicle screw fixation. METHODS: Forty-two consecutive patients who had undergone uni- or bilateral TLIF between February 1999 and July 2000 were prospectively evaluated. Clinical outcome was graded using a modified Prolo Scale, the McGill Pain Index Scale, a follow-up questionnaire, and charts. An independent radiologist assessed radiological outcomes. All patients were followed for at least 1 year. Based on Prolo Scale scores, an excellent or good 1-year outcome was achieved in 73% of patients; 90% of patients responded that they would undergo the procedure again. At 1 year, radiographic fusion was demonstrated in 74% and was statistically related to clinical outcome (p < 0.05). There were no deaths or major hardware failures. Complications requiring repeated surgery included one case of cerebrospinal fluid (CSF) leakage and one case in which the hemovac drain was retained. There were four cases involving minor wound infections, eight involving CSF leaks, and none requiring repeated surgery. On routine follow-up radiography one pedicle screw was found to be broken; the patient remained asymptomatic and fusion occurred. CONCLUSIONS: Unilateral and bilateral TLIF involving placement of carbon fiber cages and pedicle screw fixation are effective treatment options in patients with indications for lumbar arthrodesis. The procedures result in acceptable rates of fusion and clinical success, and a minimal incidence of morbidity when performed by an experienced surgeon.