Two-level Procedures Research Articles

Clinical, Radiological, and Safety Results of the Carbon Composite Cage (OSTAPEK) in Anterior Cervical Diskectomy and Fusion (ACDF): Retrospective Analysis of 54 Cases

Introduction Anterior cervical microdiskectomy and fusion with an intervertebral cage is a widely accepted procedure for the treatment of herniated cervical disc. Traditional titanium or simple plastic implant materials can limit implant performance below optimal needs: in some indications, legacy materials can be too stiff, in others not strong enough. Spinal implants constructs should not be so stiff that over time the implant works against bone's natural renewal. The Osta-Pek composite biomaterial satisfies the needs of cervical arthrodesis with motion preservation and because of the intrinsic radiolucency permits a simple and reliable radiological follow-up. Materials and Methods We operated on 54 patients (24 males and 30 females) with a mean age of 56.7 years (ranging from 26 to 65 years) at our institution. The mean follow-up was 6 months. We evaluated patients with to end points: clinical outcome (according to Odom criteria) and radiological “fusion” (fusion rate and motility). Results A total 75 cage in Osta-Pek were implanted in 32 single-level and 22 two-level procedures (one patient in two-level group had an Osta-Pek cage at one level and a Mobi-C prosthesis). Six months after surgery, there was radiographic evidence of fusion in 92% (69/75) of implants. According to Odom criteria, all patients experienced good to excellent functional recovery with preservation of cervical motility. There was any space disc collapse/pseudoarthrosis phenomenon. We experienced complications related to anterior cervical microdiskectomy in 6/54 (11%) of patients including 4 cases of transitory vocal cord paresis, 1 case of Bernard-Horner syndrome, 1 case of subfascial hematoma, and 2 cases of crashed cage during arthrodesis (evacuated in the first 24 hours). Conclusion The clinical and radiological results suggest that the carbon composite Osta-Pek frame cages are safe and effective alternative to autologous bone graft and other type of cages after anterior cervical discectomy for treatment of degenerative cervical disease Disclosure of Interest None declared References Han KW, Kim JS, Kim KH, Cho YW, Lee IC, Bae SD. Anterior cervical interbody fusion with the carbon composite Osta-Pek frame cage in degenerative cervical diseases. J Korean Neurosurg Soc 2005;37(6):422–426 Jagannathan J, Shaffrey CI, Oskouian RJ, et al. Radiographic and clinical outcomes following single-level anterior cervical discectomy and allograft fusion without plate placement or cervical collar. J Neurosurg Spine 2008;8(5):420–428 Jacobs W, Willems PC, Kruyt M, et al. Systematic review of anterior interbody fusion techniques for single- and double-level cervical degenerative disc disease. Spine 2011;36(14):E950–E960

Comparative cost effectiveness of Coflex® interlaminar stabilization versus instrumented posterolateral lumbar fusion for the treatment of lumbar spinal stenosis and spondylolisthesis

IntroductionSymptomatic chronic low back and leg pain resulting from lumbar spinal stenosis is expensive to treat and manage. A randomized, controlled, multicenter US Food and Drug Administration Investigational Device Exemption clinical trial assessed treatment-related patient outcomes comparing the Coflex® Interlaminar Stabilization Device, an interlaminar stabilization implant inserted following decompressive surgical laminotomy in the lumbar spine, to instrumented posterolateral fusion among patients with moderate to severe spinal stenosis. This study uses patient-reported outcomes and clinical events from the trial along with costs and expected resource utilization to determine cost effectiveness.MethodsA decision-analytic model compared outcomes over 5 years. Clinical input parameters were derived from the trial. Oswestry Disability Index scores were converted to utilities. Treatment patterns over 5 years were estimated based on claims analyses and expert opinion. A third-party payer perspective was used; costs (in $US 2013) and outcomes were discounted at 3% annually. Sensitivity analyses examined the influence of key parameters. Analyses were conducted using Medicare payment rates and typical commercial reimbursements.ResultsFive-year costs were lower for patients implanted with Coflex compared to those undergoing fusion. Average Medicare payments over 5 years were estimated at $15,182 for Coflex compared to $26,863 for the fusion control, a difference of $11,681. Mean quality-adjusted life years were higher for Coflex patients compared to controls (3.02 vs 2.97). Results indicate that patients implanted with the Coflex device derive more utility, on average, than those treated with fusion, but at substantially lower costs. The cost advantage was greater when evaluating commercial insurance payments. Subgroup analyses found that the cost advantage for Coflex relative to fusion was even larger for two-level procedures compared to one-level procedures.ConclusionThe Coflex Interlaminar Stabilization Device was found to be cost effective compared to instrumented posterolateral fusion for treatment of lumbar spinal stenosis. It provided higher utility at substantially lower cost.

A comparison of perioperative charges and outcome between open and mini-open approaches for anterior lumbar discectomy and fusion

The objectives of this study were to examine charge data and long-term outcomes of two approaches for anterior lumbar interbody fusion: a mini-open lateral approach (extreme lateral interbody fusion, XLIF) and an open anterior approach (anterior lumbar interbody fusion, ALIF) through retrospective chart review. A total of 202 patients underwent surgery: 87 with ALIF (Open) and 115 with XLIF (Mini-open) procedures, all with transpedicular fixation. Complications occurred in 16.7% of Open, and 8.2% of Mini-open, procedures (p = 0.041). The mean charges ($US) for one-level Mini-open and Open procedures were $91,995 and $102,146, and for two-level procedures were $124,540 and $144,183, respectively. All differences were statistically significant (p < 0.05). This represents a 10% cost-savings, based on charges, for one-level and 13.6% for two-level Mini-open compared to Open procedures. Functional outcomes improved significantly at two years for both cohorts, although the difference between groups was not statistically significant. In conclusion, the Mini-open approach, compared to the Open, resulted in clinical as well as cost benefits with similar long-term outcomes.

Utility of Computerized Isocentric Fluoroscopy for Minimally Invasive Spinal Surgical Techniques

The purpose of this study was to prospectively evaluate the clinical utility and accuracy of intraoperative three-dimensional fluoroscopy as an adjunct for the placement of a complex spinal instrumentation. The Siemens Iso-C three-dimensional fluoroscopy unit in the combination with the Stealth Treon computer volumetric navigational system was used. A total of 279 spinal instrumentation screws or transpedicular cannulations were performed in 69 patients. Accuracy, operative time, and amount of fluoroscopy utilization time were assessed for transforaminal lumbar interbody fusion (TLIF) and kyphoplasty cases. Only 4 percutaneous transpedicular lumbar screws out of 265 total (1.5%) were malpositioned. Average operative time for TLIF cases was 185 minutes (range 114-311 minutes) for one-level and 292.6 minutes (range 173-390 minutes) for two-level procedures. Biplanar fluoroscopy utilization time was 93 seconds (range 27-280 seconds) for one-level procedures and 216 seconds (range 80-388 seconds) for two-level procedures. Average surgery duration for kyphoplasty was 60 minutes (range 36-79 minutes) for one-level procedures and 68.5 minutes (range 65-75 minutes) for two-level cases. Biplanar fluoroscopy utilization time was 41.3 seconds per case (range 25-62 seconds). Use of intraoperative three-dimensional fluoroscopy for image guidance in minimally invasive complex spinal instrumentation procedures is feasible and safe. This technique provides excellent visualization of three-dimensional relationships. This potentially results in improved accuracy of screw positioning and the ability to detect misplaced screws prior to wound closure. This technique also potentially results in a significant reduction in radiation exposure for both the patient and the staff.

Clinical and Radiological Outcomes With the Charité™ Artificial Disc

This is the first report of clinical and radiologic outcomes for the CHARITE artificial disc with a minimum follow-up of 10 years. A total of 107 patients indicated for total lumbar disc replacement were implanted with the CHARITE prosthesis. Of these 107, 100 were followed for a minimum of 10 years (range 10-13.4 years). A total of 147 prostheses were implanted with 54 one-level and 45 two-level procedures and 1 three-level procedure. The prostheses were placed through a standard anterior retroperitoneal approach. Clinically, 62% had an excellent outcome, 28% had a good outcome, and 10% had a poor outcome. Of the 95 eligible to return to work, 88 (91.5%) either returned to the same job as prior to surgery or a different job. These included 63.2% (12) of those working in heavy labor employment returning to the same job. Mean flexion/extension motion was 10.3 degrees for all levels (12.0 degrees at L3-L4, 9.6 degrees at L4-L5, 9.2 degrees at L5-S1). Mean lateral motion was 5.4 degrees . In the sagittal plane, 9 (6.1%) were anterior of geometric center, 50 (34.0%) were centered, and 88 (59.9%) were posterior of center. In the frontal plane, 110 (75%) were centered, and 37 (25%) were noted to be lateral to center. Slight subsidence was observed in two patients, but they did not require further surgery. No subluxation of the prostheses and no cases of spontaneous arthrodesis were identified. There was one case of disc height loss of 1 mm. Five patients required a secondary posterior arthrodesis. A good or excellent clinical outcome rate of 90% and a return to work rate of 91.5% compare favorably with results described in the literature for fusion for the treatment of lumbar degenerative disc disease. With a minimum follow-up of 10 years, the CHARITE artificial disc demonstrated excellent flexion/extension and lateral range of motion with no significant complications.

Early results after ProDisc-C cervical disc replacement

Cervical anterior decompression and total-disc replacement is currently being investigated as an alternative treatment in patients with symptomatic intervertebral cervical spondylosis with and without radiculopathy. The authors prospectively investigated the safety and efficacy of using the ProDisc-C disc for cervical arthroplasty in the treatment of symptomatic cervical spondylosis. Sixteen patients in whom a diagnosis of symptomatic cervical spondylosis had been established were prospectively treated with complete anterior cervical discectomy and ProDisc-C cervical disc arthroplasty. Overall 12 single- and four two-level procedures were performed (20 prostheses). Patients underwent pre- and multiple postoperative assessments (3 and 6 weeks and 3, 6, and 12 months). The median age of all patients was 50 years (range 32-60 years). Levels of surgery included seven C5-6, six C6-7, and three C4-5. Neck and arm pain as well as disability scores were significantly improved by 3 months and remained significantly improved at 1 year. No additional fusion surgeries were necessary at the affected or unaffected levels. Radiography revealed an affected disc motion from 4 to 12 degrees. No surgery- or device-related complications were documented. Analysis of preliminary results involving ProDisc-C arthroplasty indicates significant improvement in pain and functional outcome scores. No spontaneous fusions at the level of surgery or at adjacent levels were noted. Long-term follow-up studies will be necessary before more definitive treatment recommendations can be formulated.

Packing of Intervertebral Spaces with Oxidized Regenerated Cellulose to Prevent the Recurrence of Lumbar Disc Herniation

Abstract OBJECTIVE To investigate the impact of packing of intervertebral spaces with oxidized regenerated cellulose (ORC) on the incidence of recurrence of lumbar disc herniation (LDH). METHODS We retrospectively reviewed 158 consecutive patients who underwent surgery for a newly diagnosed LDH and had a minimum of 18 months of follow-up. Single-level (151 patients) and two-level (7 patients) procedures accounted for 165 microdiscectomies. After microsurgical removal of disc herniation and curettage, the interspaces were tightly packed with ORC. RESULTS The average hospital stay was 1.47 days, without any relevant and permanent complications. In particular, complications related to intervertebral ORC packing were never observed. At a median follow-up of 29 months (range, 18–51 mo), the pain decreased or disappeared in almost all patients and the patient satisfaction rate was very high. A recurrence of LDH was observed in two patients (1.34%), both of whom needed a second operation. Three patients (2.01%) experienced a disc herniation involving another intervertebral space. CONCLUSION Our preliminary results suggest that the packing of intervertebral spaces with ORC at the end of microdiscectomy is a safe technique that may reduce the incidence of recurrent LDHs, although the true impact of this technique on long-term follow-up is still unclear. At the moment, it seems reasonable to assume that this technique should be used only under the auspices of large clinical investigations with prospective and randomized protocols.

Packing of Intervertebral Spaces with Oxidized Regenerated Cellulose to Prevent the Recurrence of Lumbar Disc Herniation

To investigate the impact of packing of intervertebral spaces with oxidized regenerated cellulose (ORC) on the incidence of recurrence of lumbar disc herniation (LDH). We retrospectively reviewed 158 consecutive patients who underwent surgery for a newly diagnosed LDH and had a minimum of 18 months of follow-up. Single-level (151 patients) and two-level (7 patients) procedures accounted for 165 microdiscectomies. After microsurgical removal of disc herniation and curettage, the interspaces were tightly packed with ORC. The average hospital stay was 1.47 days, without any relevant and permanent complications. In particular, complications related to intervertebral ORC packing were never observed. At a median follow-up of 29 months (range, 18-51 mo), the pain decreased or disappeared in almost all patients and the patient satisfaction rate was very high. A recurrence of LDH was observed in two patients (1.34%), both of whom needed a second operation. Three patients (2.01%) experienced a disc herniation involving another intervertebral space. Our preliminary results suggest that the packing of intervertebral spaces with ORC at the end of microdiscectomy is a safe technique that may reduce the incidence of recurrent LDHs, although the true impact of this technique on long-term follow-up is still unclear. At the moment, it seems reasonable to assume that this technique should be used only under the auspices of large clinical investigations with prospective and randomized protocols.

One- and two-level anterior cervical discectomy and fusion: the effect of plate fixation

The success of arthrodesis for anterior cervical fusion depends on several factors, including the number of surgical levels. Internal fixation putatively improves the arthrodesis rate and outcome. To provide medium-term follow-up data on the surgical success and patient outcome of one- and two-level anterior cervical discectomies and fusions and to determine the effect that plate fixation has on results. A prospective study of 40 patients who underwent modified Smith-Robinson anterior cervical discectomy and fusion at one or two operative levels. Forty patients. Odom criteria, Nurick grading system, radiographs. Forty patients, with an average age of 44 years (range, 27 to 82), were followed for an average of 51 months (range, 24 to 85). All had an anterior discectomy, burring of the end plates and placement of an autogenous tricortical iliac crest graft at one (20 patients) or two levels (20 patients). Twenty-three were stabilized with the Cervical Spine Locking Plate (Synthes Spine, Paoli, PA), 4 single level, 19 two level. All patients had follow-up office visits with examinations and radiographs. Radiographic union, postoperative pain relief and neurologic recovery were evaluated. Successful arthrodesis of single-level procedures occurred in 11 of 16 unplated and 2 of 4 plated fusions. Primary bony union in the two-level group was achieved in 15 of 19 plated patients and did not occur in the single unplated procedure. Clinically, there were 12 excellent, 5 good, 3 satisfactory and 0 poor outcomes among the single-level procedures. Among the dual-level procedures, there were 10 excellent, 5 good, 3 satisfactory and 2 poor results. Nine of 16 who developed adjacent-level degeneration had pain. Five of the 9 also had nonunions. Of the 40, 3 had fibrous union at final follow-up, and 10 had revision surgery. The Cervical Spine Locking Plate improved the outcome of two-level procedures to that of uninstrumented one-level fusions. Adjacent-level degeneration is associated with persistent pain, especially if there is also a nonunion. Primary bony union is paralleled by a better clinical outcome.

Anterior cervical fusion with carbon fiber cage containing coralline hydroxyapatite: preliminary observations in 45 consecutive cases of soft-disc herniation.

The purposes of bone substitutes for anterior cervical fusion (ACF) are immediate biomechanical support and osteointegration of the graft. The authors report their preliminary results in performing ACF in which carbon fiber cages (CFCs) containing coralline hydroxyapatite (HA) are used as bone substitute. During a 24-month period, anterior microsurgical discectomy was performed in 45 consecutive patients for soft-disc cervical herniation. In all cases ACF was performed using a CFC containing a core of granulated coralline HA. Fifty-seven CFCs were implanted in 33 single-level and 12 two-level procedures. The mean operative time was 83 minutes for one-level and 97 minutes for two-level procedures. The mean hospital stay was 1.51 days, and there were no permanent complications. At a mean follow up of 22.3 months, the pain had decreased or disappeared in all patients, and the patients' satisfaction rate was very high. Good results were also obtained in patients who smoked cigarettes. Patients underwent radiographic evaluation at Day 1, and 1, 3, 6, and 12 months postoperatively. Implant-related complications were not observed and revision surgeries were not performed. Twelve-month cervical x-ray films demonstrated complete fusion in all cases, without evidence of breakage, collapse, pseudarthrosis, subsidence, angular deformity, or protrusion. Signs of pathological absorption and necrosis were not found in contiguous vertebral bodies, and inflammatory reactions were never seen around cages. These preliminary results suggest that implants composed of CFC containing granulated coralline HA are promising bone substitutes to be used in ACF, with a good rate of incorporation and no significant complications.

Anterior Cervical Plating Enhances Arthrodesis after Discectomy and Fusion with Cortical Allograft

OBJECTIVE Anterior plate fixation has gained widespread acceptance for the treatment of cervical spondylosis, theoretically enhancing the rate of arthrodesis. There are few studies comparing fusion rates after anterior cervical discectomy and fusion (ACDF) with and without a plate. The purpose of this study was to evaluate the efficacy of anterior cervical plating for fusion enhancement after one- and two-level ACDF with cortical allograft. METHODS A retrospective review was performed with 251 patients who underwent one- or two-level ACDF with cortical allograft and plate stabilization between 1993 and 1999. An independent surgeon reviewer determined fusion status and complications. A successful fusion was defined by the absence of lucency around the graft, evidence of bridging bone between the endplate and the graft, and the absence of movement on dynamic imaging scans. Follow-up data, ranging from 9 months to 3.6 years, were available for 233 patients. A control group of 289 patients who underwent ACDF without plating was described in a previously published report by the senior author (RWH). Therefore, a total of 540 patients were evaluated for determination of the efficacy of anterior cervical plating with cortical allograft bone. Statistical significance was determined by χ2 test. RESULTS The fusion rates for one- and two-level ACDF with anterior fixation were 96 and 91%, respectively, compared with 90 and 72% for one- and two-level ACDF without anterior fixation. The observed increases in fusion rates for both one- and two-level procedures proved to be statistically significant (P < 0.05). There were no recorded infectious, neurological, or graft-related complications among the cohort treated with anterior cervical plating. Compared with the results for the cohort treated without anterior cervical plates, there was a statistically significant decrease in the graft-related complication rate with the application of plates (P < 0.001). Two patients who received plates were noted to have adjacent-segment degenerative changes that required surgical intervention. No hardware fractures were noted; however, one patient was noted to have a single displaced screw, without clinical consequences. CONCLUSION The use of anterior cervical plating after one- and two-level ACDF with allograft cortical bone significantly enhanced arthrodesis. The improved fusion rate and negligible complication rate associated with anterior cervical plating are compelling factors justifying its use in the treatment of cervical spondylosis.

The Use of Freeze-Dried Allograft Bone for Anterior Cervical Fusions

A consecutive series of 87 patients undergoing Smith-Robinson anterior cervical fusion were analyzed. Either freeze-dried tricortical iliac crest bone or tricortical autograft bone was used. Surgical technique was otherwise identical. Radiography showed delayed union at 3 months in 13% of patients with autograft and in 37% of patients with freeze-dried allograft. At 1 year, radiography showed nonunion in 8% of patients with autograft and in 22% of patients with allograft. One-level procedures had a delayed union rate of 7% for autograft and 21% for allograft. Nonunion in one-level procedures was 5% for both autograft and allograft. For two-level procedures, the nonunion rate was 17% for autograft and 63% for allograft. Graft collapse was more commonly seen with freeze-dried allograft (30%) than with autograft (5%). Relief of neck and arm pain, however, was similar in both groups.