Idiopathic spinal cord herniation: case report and review of the literature.

BACKGROUND: Idiopathic spinal cord herniation (ISCH) is a rare cause of progressive myelopathy frequently present in Brown-Séquard syndrome. Preoperative diagnosis can be made with magnetic resonance imaging (MRI). Many surgical techniques have been applied by various authors and are usually reversible by surgical treatment. METHODS: Case report and review of the literature. FINDINGS: A 45-year-old woman with Brown-Séquard syndrome underwent thoracic MRI, which revealed transdural spinal cord herniation at T8 vertebral body level. During surgery the spinal cord was reduced and the ventral dural defect was restorated primarily and reinforced with a thin layer of subdermal fat. The dural defect was then closed with interrupted stitches. RESULTS: Although neurologic status improved postoperatively, postsurgical MRI demonstrated swelling and abnormal T2-signal intensity in the reduced spinal cord. Review of the English language literature revealed 100 ISCH cases. CONCLUSIONS: ISCH is a rare clinical entity that should be considered in differential diagnosis of Brown-Séquard syndrome, especially among women in their fifth decade of life. Outcome for patients who initially had Brown-Séquard syndrome was significantly better than for patients who presented with spastic paralysis. Although progression of neurologic deficits can be very slow, reduction of the spinal cord and repair of the defect are crucial in stopping or reversing the deterioration.

Recurrent radiculopathy caused by epidural gas after spinal surgery: report of four cases and literature review.

STUDY DESIGN: The article presents and discusses 4 cases in which symptomatic epidural gas developed after different surgeries on the lumbar spine. OBJECTIVE: To raise spinal surgeons' awareness of this potential problem. SUMMARY OF BACKGROUND DATA: Vacuum phenomenon (gas accumulation in an intervertebral disc) is relatively common. Gas can also spontaneously enter and collect in the epidural space, but symptomatic epidural gas after spinal surgery is very rare. To date, only 5 such cases after lumbar surgery have been reported. METHODS: The primary disorders in the 4 new cases were disc extrusion at L2-L3 (Case 1), disc degeneration and herniation at L4-L5 (Case 2), stenosis of the lumbar spinal canal (Case 3), and disc herniation at L5-S1 with spinal canal stenosis (Case 4). The corresponding surgeries performed were L2-L3 microdiscectomy, L4-L5 microdiscectomy with instrumentation, right unilateral hemilaminotomy with complete instrumentation, and L5-S1 microdiscectomy. All 4 patients developed unexpected postoperative complaints of low back and radicular pain. Each was investigated with computed tomography and magnetic resonance imaging. The images revealed epidural gas collections compressing the thecal sac and/or nerve roots. RESULTS: Conservative management was effective in all but 1 case. In the latter case, computed tomography-guided needle aspiration was performed, but this did not resolve the problem. Surgery led to a favorable outcome, and follow-up lumbar computed tomography showed no epidural gas. CONCLUSION: Epidural gas after lumbar surgery is very rare but can cause unexpected postoperative back or radicular pain. Combined computed tomography and magnetic resonance imaging should be used to identify the problem and rule out other disorders. Conservative treatment should be the first-line approach but surgery is often necessary if this does not resolve the problem.

Preserving the ligamentum flavum in lumbar discectomy: a new technique that prevents scar tissue formation in the first 6 months postsurgery.

OBJECTIVE: Postoperative fibrosis is one of the most important causes of failed back surgery syndrome after lumbar disc surgery. Numerous natural and synthetic materials have been investigated as means to prevent or reduce postoperative scarring after these operations. Preservation of the ligamentum flavum for this purpose has not been studied in depth. A prospective, randomized, controlled clinical study was conducted. The aim was to present a new technique for preserving the ligamentum flavum during lumbar discectomy, and to evaluate whether this helps prevent or diminish postoperative fibrosis. METHODS: Twenty patients with unilateral L5-S1 disc herniation were randomly divided into two equal groups. Group A patients underwent classic microlumbar discectomy, and Group B patients underwent the same procedure but with preservation of the ligamentum flavum. Visual analog pain scale (VAPS) scores, Oswestry scale scores, and straight-leg raising angles were recorded preoperatively and at 6 months postoperatively. Differences between the pre-operative and postoperative findings for each group were statistically compared using the Wilcoxon test. Magnetic resonance imaging was also done at 6 months to assess the extent of postoperative fibrosis, and a "scarring grade" was recorded for each patient. The group findings for this were analyzed with Levene's test. RESULTS: Both groups' clinical parameters were significantly improved at 6 months postsurgery. In Group A, the mean pre- and postoperative VAPS scores were 9.2 and 3.2, respectively (P < 0.05); the corresponding mean Oswestry scale scores were 88 and 28.2, respectively (P < 0.05); and the corresponding mean straight-leg raising angles were 290 and 630, respectively (P < 0.05). In Group B, the mean pre- and postoperative VAPS scores were 9.2 and 2.6, respectively (P < 0.05); the corresponding mean Oswestry scores were 85.2 and 22.2, respectively (P < 0.05); and the corresponding mean straight-leg raising scores were 260 and 710, respectively (P < 0.05). The mean scarring grades in Groups A and B were 1.8 and 1.0, respectively (P < 0.05). CONCLUSION: The groups both showed satisfactory clinical outcomes and the improvements were comparable; however, the group with preserved ligamentum flavum showed significantly less local fibrosis at 6 months postoperatively. The authors speculate that this surgical technique provides a physical protective barrier that can reduce or even eliminate fibrosis-related complications after lumbar disc surgery.