Microdecompressive laminatomy with a 5-year follow-up period for severe lumbar spinal stenosis.

STUDY DESIGN: The 2 groups of patients with severe lumbar spinal stenosis were prospectively compared as a case control study. OBJECTIVES: This prospective case control study sought to evaluate bilateral microdecompressive laminatomy (MDL) for treatment of severe lumbar spinal stenosis. SUMMARY OF BACKGROUND DATA: Total laminectomy is a general consensus on the therapy of severe spinal stenosis. The authors tried to investigate a new minimal invasive approach. METHODS: Patients were randomly divided into 2 groups. In first group, 34 patients underwent total laminectomy (TL) for severe lumbar spinal stenosis. In the second group, 37 patients with the same diagnosis underwent bilateral MDL. The groups were compared for disability, walking distance, degree of postoperative back and leg pain, perioperative complications, and postoperative instability. Radiographic analyses were performed at regular intervals to demonstrate satisfactory decompression. RESULTS: Mean follow-up was 5 years. Postoperative computerized tomography and magnetic resonance imaging demonstrated adequate decompressions in both groups. The walking distance, pain control, and disability scores were slightly higher among patients in the MDL group, although these results did not achieve statistical significance. Perioperative complications and postoperative instability were significantly higher in the TL group (P<0.05). CONCLUSIONS: Compared with classic approaches, bilateral MDL provides adequate and safe decompression in lumbar spinal stenosis. It significantly reduces clinical symptoms and disability. However, TL shows higher perioperative complications and postoperative instability. To the best of our knowledge, this is the first study to define a bilateral MDL approach to treat the stenotic lumbar spine without a herniated disc.

Mitomycin protection of peridural fibrosis in lumbar disc surgery.

OBJECT: In this prospective, randomized clinical study the authors sought to evaluate the effects of locally applied mitomycin C on peridural fibrosis during lumbar microdiscectomy. METHODS: Patients undergoing lumbar disc surgery were randomly divided into 2 groups. Thirty patients had 1 mg/ml mitomycin C applied at the site of discectomy for 5 minutes, and 30 age- and sex-matched patients underwent lumbar microdiscectomy without mitomycin C application as the control group. The groups were compared for degree of postoperative neurological function, radicular/back pain, and degree of peridural fibrosis on MR imaging 6 months after the operation. RESULTS: The median follow-up was 18 months. No serious drug adverse effects and no clinically significant laboratory adverse effects were reported in patients in the mitomycin C group. Patients in both groups showed similar clinical recoveries postoperatively. On postoperative evaluation of the MR images, pain scores, and neurological function, patients given mitomycin C have shown no reduction of peridural fibrosis either clinically or radiographically. CONCLUSIONS: Mitomycin C is easy to use and safe in patients undergoing lumbar microdiscectomy. However, no benefit was observed either clinically or radiographically in this study.

Lumbar facet joint angle and its importance on joint violation in lumbar microdiscectomy.

OBJECTIVE: We investigated facet joint angle at the level of the nucleus pulposus in herniated disks and documented the importance of this angle in preserving articulation and surgical view in patients undergoing lumbar microdiscectomy. METHODS: In this prospective study using pre- and postoperative magnetic resonance imaging scans, two blinded radiologists measured and inspected the facet joint angles in 168 patients. Patients were treated with single-level, unilateral, lumbar microdiscectomy. Postoperatively, patients were divided into two groups according to whether or not any portion of the facet joint had been violated during surgery. Using the magnetic resonance imaging scans, the angles of the facet joints were measured and then correlated with whether or not the facet joint was preserved. RESULTS: The follow-up period for this study was 6 months. Postoperative radicular and back pain during the follow-up period and the need for opioids in the early postsurgery period (48 h) were higher in the nonpreserved group, but these differences were not statistically significant (P > 0.05). If the facet joint angle at the disc was lower than 35 degrees in the horizontal plane, articulation cannot be preserved. However, if this angle is greater than 35 degrees, articulation may be preserved and the surgical view is satisfactory for lumbar microdiscectomy. CONCLUSION: The angle of the lumbar facet joint is important to protect articulation during lumbar microdiscectomy, and violating the facet joint may affect early postoperative pain. A facet angle of less than 35 degrees does not allow for a safe surgical corridor in which to use instruments, nor does it provide a satisfactory view for the surgeon.