Comparison of BRYAN cervical disc arthroplasty with anterior cervical decompression and fusion: clinical and radiographic results of a randomized, controlled, clinical trial.

STUDY DESIGN: A prospective, randomized, multicenter study of surgical treatment of cervical disc disease. OBJECTIVE: To assess the safety and efficacy of cervical disc arthroplasty using a new arthroplasty device at 24-months follow-up. SUMMARY OF BACKGROUND DATA: Cervical disc arthroplasty preserves motion in the cervical spine. It is an alternative to fusion after neurologic decompression, whereas anterior decompression and fusion provides a rigorous comparative benchmark of success. METHODS: We conducted a randomized controlled multicenter clinical trial enrolling patients with cervical disc disease. Ultimately 242 received the investigational device (Bryan Cervical Disc), and 221 patients underwent a single-level anterior cervical discectomy and decompression and fusion as a control group. Patients completed clinical and radiographic follow-up examinations at regular intervals for 2 years after surgery. RESULTS: Analysis of 12- and 24-month postoperative data showed improvement in all clinical outcome measures for both groups; however, 24 months after surgery, the investigational group patients treated with the artificial disc had a statistically greater improvement in the primary outcome variables: Neck disability index score (P = 0.025) and overall success (P = 0.010). With regard to implant- or implant/surgical-procedure-associated serious adverse events, the investigational group had a rate of 1.7% and the control group, 3.2%. There was no statistical difference between the 2 groups with regard to the rate of secondary surgical procedures performed subsequent to the index procedure. Patients who received the artificial cervical disc returned to work nearly 2 weeks earlier than the fusion patients (P = 0.015). CONCLUSION: Two-year follow-up results indicate that cervical disc arthroplasty is a viable alternative to anterior cervical discectomy and fusion in patients with persistently symptomatic, single-level cervical disc disease.

Quality of life of lumbar stenosis-treated patients in whom the X STOP interspinous device was implanted.

OBJECT: This study was conducted to compare the quality of life (QOL) in patients with neurogenic intermittent claudication (NIC) secondary to lumbar spinal stenosis (LSS). Using the 36-Item Short Form (SF-36) questionnaire, the authors compared the results obtained in patients treated with the X STOP Interspinous Process Decompression (IPD) System with those obtained in patients who underwent nonoperative therapies. METHODS: Patients with LSS were enrolled in a prospective 2-year multicenter study and randomized either to the X STOP or nonoperative group. The SF-36 survey was used to assess the QOL before treatment and at 6 weeks, 6 months, 1 year, and 2 years posttreatment. An analysis of variance was used to compare individual pre- and posttreatment mean SF-36 domain scores between the two groups and within each treatment group. At all posttreatment time points, the authors observed the following: (1) mean domain scores in X STOP-treated patients were significantly greater than those in patients treated nonoperatively, with the exception of the mean General Health (GH), Role Emotional, and Mental Component Summary scores at 2 years; and (2) mean posttreatment domain scores documented in X STOP-treated patients were significantly greater than mean pretreatment scores, with the exception of mean GH scores at 6, 12, and 24 months. CONCLUSIONS: The results of this study demonstrate that the X STOP device is significantly more effective than nonoperative therapy in improving the QOL in patients with LSS. The results are comparable with those reported in other studies involving traditional decompressive techniques for LSS and suggest that the X STOP implant can provide an effective treatment compared with nonoperative and conventional surgical therapies.

A multicenter, prospective, randomized trial evaluating the X STOP interspinous process decompression system for the treatment of neurogenic intermittent claudication: two-year follow-up results.

STUDY DESIGN: A randomized, controlled, prospective multicenter trial comparing the outcomes of neurogenic intermittent claudication (NIC) patients treated with the interspinous process decompression system (X STOP) with patients treated nonoperatively. OBJECTIVE: To determine the safety and efficacy of the X STOP interspinous implant. SUMMARY OF BACKGROUND DATA: Patients suffering from NIC secondary to lumbar spinal stenosis have been limited to a choice between nonoperative therapies and decompressive surgical procedures, with or without fusion. The X STOP was developed to provide an alternative therapeutic treatment. METHODS.: 191 patients were treated, 100 in the X STOP group and 91 in the control group. The primary outcomes measure was the Zurich Claudication Questionnaire, a patient-completed, validated instrument for NIC. RESULTS: At every follow-up visit, X STOP patients had significantly better outcomes in each domain of the Zurich Claudication Questionnaire. At 2 years, the X STOP patients improved by 45.4% over the mean baseline Symptom Severity score compared with 7.4% in the control group; the mean improvement in the Physical Function domain was 44.3% in the X STOP group and -0.4% in the control group. In the X STOP group, 73.1% patients were satisfied with their treatment compared with 35.9% of control patients. CONCLUSIONS: The X STOP provides a conservative yet effective treatment for patients suffering from lumbar spinal stenosis. In the continuum of treatment options, the X STOP offers an attractive alternative to both conservative care and decompressive surgery.

Anterior cervical fusion: a comparison of cage, dowel and dowel-plate constructs.

BACKGROUND CONTEXT: Threaded lumbar cages have been used as a safe and effective surgical fusion method for a decade. Smaller versions have now been developed for the cervical spine to obviate the need for allograft use or iliac autograft harvest and to provide initial stability before fusion. PURPOSE: To compare anterior cervical interbody fusion with the BAK/C Cervical Interbody Fusion System, cage (Centerpulse Spine-Tech Inc., Minneapolis, MN), conventional anterior cervical discectomy and fusion (ACDF) and plate constructs (anterior cervical locking plates). STUDY DESIGN/SETTING: Radiological and clinical outcomes of patients who underwent cervical fusion with the BAK/C (filled with local autograft reamings) are compared with ACDF and plate fusion constructs (anterior cervical locking plates). One surgeon performed 88 fusions: BAK/C (n=30), ACDF (n=32), plate (n=26). There were 43 one-level and 45 two-level fusions from C3-C4 to C7-T1. PATIENT SAMPLE: The patients represented a wide range of diagnoses as indications for cervical fusion. Patients (n=88) were 40 men (45%) and 48 women (55%) with a mean age of 51 years (range, 30 to 70 years). Thirty-five percent of patients were smokers, and 26% had known workers' or other compensation issues. OUTCOME MEASURES: Hospital records were examined for data from operative reports and discharge summaries. An independent spine radiologist performed a radiological review of cervical flexion and extension films, noting fusion status, graft position and cage subsidence. Short Form (SF)-36 inventories for physical/mental functioning and visual analog scales (VAS) for pain were administered. METHODS: A retrospective clinical and radiological review was performed. Hospital and clinic chart data, flexion-extension X-rays and self-assessments (SF-36, VAS) were evaluated. Follow-up at X-ray was 2.4 years (range, 1.0 to 5.5 years). RESULTS: Iliac crest harvesting was least likely for BAK/C patients (2 of 30; 6.7%) compared with ACDF (30 of 32; 93.8%) and plate patients (13 of 26; 50.0%; p<.0001). Plate surgeries took longest (3.5 hours), followed by ACDF (2.3 hours) and BAK/C (2.2 hours; p<.0001). Blood loss was greatest for plate procedures (289 cc), followed by BAK/C (142 cc) and ACDF (121 cc; p<.01). No BAK/C patient stayed in the hospital more than 1 day; ACDF, 1 to 2 days; plate, 1 to 5 days (p<.02). BAK/C patients were most likely to have a successful fusion: BAK/C, 29 of 30, 97%; ACDF, 26 of 31, 84% (one X-ray fusion status indeterminate); plate, 22 of 26, 85% (p<.0585). No BAK/C patient experienced prolonged donor-site pain (0%) compared with ACDF (25.0%) and plate (23.0%) patients. SF-36 and VAS scores, influenced by compensation, were comparable for all groups. Revisions were as follows: ACDF, 4 of 32, 13%; plate, 2 of 26, 8%); BAK/C, 1 of 30, 3%). CONCLUSIONS: In this study, the BAK/C cage group had the lowest graft requirements/risks, generally required fewer hospital resources, achieved similar patient outcomes and fused at a higher rate than ACDF and plate groups.