Minimally Invasive Microscopic Decompression with Tubular Retractor System in Lumbar Spinal Stenosis: Results Comparing with Open Microscopic Decompression / 대한척추외과학회지

PURPOSE: To compare the two methods of decompression using a microscope with a tubular retractor system and open microscopic decompression in lumbar spinal stenosis. MATERIALS AND METHODS: The records of patients that had undergone decompression from May 2000 to April 2005 were reviewed. The average follow-up period was 29 months (4~60 months). The duration of hospital stay, estimated blood loss, relief of pain, and operating time were reviewed retrospectively. Analysis was conducted by telephone interview and chart review (McNab's criteria). Pre- and post-operative Visual Analogue Scale (VAS) scores and JOA scores were also evaluated. RESULTS: Of the total 53 patients, open microscopic decompression was performed on 27 patients, and 26 patients received surgery using microscopic decompression with tubular retractors. There were no patients who had serious complications such as infection or nerve root injury in either of the groups. The average estimated blood loss was 205 cc for the open microscopic decompression group versus 120 cc in the minimally invasive microscopic decompression (MIMD) group (p=0.019). The mean operating time was 2.5 hours in the open microscopic decompression group and 2.2 hours in the MIMD group (p=0.048). As shown by the clinical results, good or excellent results were shown by the McNab's criteria after operation, 85.1% for the open microscopic decompression group and 94.7% for the MIMD group, respectively. The JOA score improved after surgery, with average scores of 14.5 to 24.5 in the open microscopic decompression group, and 15.9 to 25.6 in the MIMD group. The VAS score was reduced after surgery, with an average score of 8.0 to 3.7 in the open microscopic decompression group, and 8.3 to 2.6 in the MIMD group. CONCLUSION: In terms of blood loss, the MIMD group showed significantly better results than the open microscopic decompression group. The clinical results showed no statistically significant difference between the two groups.

Open Kyphoplasty Combined with Microscopic Decompression for the Osteoporotic Burst Fracture

OBJECTIVE: The purpose of this retrospective clinical study was to describe a treatment for osteoporotic burst fracture in the setting of severe fractures involving fragmentation of the posterior wall and neural compromise with symptoms of cord compression. METHODS: Indication for microscopic decompression and open kyphoplasty were intractable pain at the level of a known osteoporotic burst fractures involving neural compression or posterior wall fragmentation. A total of 18 patients (mean age, 74.6 years) with osteoporotic thoracolumbar burst fractures (3 males, 15 females) were included in this study. In all cases, microscopic decompressive laminectomy was followed by open kyphoplasty. Clinical outcome using VAS score and modified MacNab's grade was assessed on last clinical follow up (mean 6.7 months). Radiological analysis of sagittal alignment was assessed preoperatively, immediately postoperatively, and at final follow up. RESULTS: One level augmentation and 1.8 level microscopic decompression were performed. Mean blood loss was less than 100 ml and there were no major complications. The mean pain score before operation and at final follow up was 7.2 and 1.9, respectively. Fourteen of 18 patients were graded as excellent and good according to the modified MacNab's criteria. Overall, 6.0 degrees of sagittal correction was obtained at final follow-up. CONCLUSION: The combined thoracolumbar microscopic decompression and open kyphoplasty for severe osteoporotic fractures involving fragmentation of posterior wall and neural compromise provide direct visualization of neural elements, allowing safe cement augmentation of burst fractures. Decompressive surgery is possible and risk of epidural cement leakage is controlled intraoperatively.

Selective Microscopic Decompression for Multi-level Lumbar Spinal Stenosis: More than 5 Years Follow Up / 대한척추외과학회지

STUDY DESIGN: A rectrospective study of microscopic lumbar decompressions was performed elderly patients suffering from multiple level of lumbar stenosis. OBJECTIVES: The Purpose of this study were to assess the outcome of this procedure performed only microscopic decompression on multiple lesions in 5 years follow up and to identify the clinical features of the elderly patients with multiple stenosis. SUMMARY OF BACKGROUND DATA: There was a common to perform fusion and instrumentation in spinal stenosis surgery, because of extensive decompression and instability. However the introduction of microscope in spine operation can minimize lesions and the incidence of spinal fusion. MATERIALS AND METHODS: Twenty-one patients were identified as having had a microscopic decompression without arthrodesis, for degenerative lumbar spinal stenosis over 60 years. The follow up period was more than 5 years. The clinical results was evaluated by Low-Back Outcome scale. RESULTS: Ten cases were above good results in two levels involved 14 cases, 4 cases above good results in three levels involved 6 cases, one case above good results in four levels. In the cases of affected duration, 4 of 5 cases in less than 1 year, 8 of 12 cases in 1 to 5 years, 3 of 4 cases in more than 5 years were above good results by the criteria. We had calculated the average score (54.8) and concluded that the long-term outcome of decompressive surgery in the elderly is good. CONCLUSION: Selective microscopic decompression is one of the effective method for the elderly patients or patients with osteoporosis in addition to multiple stenotic lesions. And preoprative root block is also useful for selective microscopic decompression.

Clinical Analysis of Less Extensive Microsurgical Decompression for Lumbar Spinal Stenosis

The cases of twenty-eight patients with spinal stenosis treated by microscopic decompressive surgery from January 1991 to September 1995, were analysed in an attempt to define is clinical feature, and to evaluate the results of our modified operation technique of preventing postoperative spinal instability. The main age group of the patients were in the fifties and sixties. On plain X-ray, most lumbar spine of the patients showed degenerative change. Pain in lower back and legs were the most common symptom, and intermittent neurogenic claudication was presented in three quarters of the patients. Radiologically, the diagnosis was confirmed by either myelography, CT, and MRI or by their combination. The major etiologic factors were thickening of ligamentum flavum, hypertrophy of laminae or facet joints and associated herniated nucleus pulposus. Since a significant rate of postdecompressive instability had been reported by other authors, therefore we have decided to performed less extensive decompressive total laminectomy procedure. The outcome of our decompressive laminectomy was favorable. In patients with no preoperative instability, newly developed instability following the less extensive decompressive total laminectomy was none.