[Short-term effectiveness of interlaminar lumbar instrumented fusion through a small incision for lumbar spinal stenosis].

OBJECTIVE: To evaluate the short-term effectiveness of local laminectomy and interlaminar lumbar instrumented fusion (ILIF) through a small incision for lumbar spinal stenosis. METHODS: Between November 2009 and January 2011, 16 patients with lumbar spinal stenosis were treated by local laminectomy and ILIF through a small incision. There were 7 males and 9 females with an average age of 52.8 years (range, 49-67 years). Sixteen patients had lumbar degenerative stenosis with an average disease duration of 4 years and 7 months (range, 2 years-9 years and 4 months). Four cases complicated by lateral recessus stenosis, 3 by lumbar disc herniation. Involved segments included L3,4 in 2 cases, L4,5 in 4 cases, L5, S1 in 4 cases, L3,4 and L4,5 (double segments) in 2 cases, L4,5 and L5, S1 (double segments) in 4 cases. The effectiveness was evaluated with the pre- and post-operative Visual Analogue Scale (VAS) scores, Oswestry Disability Index (ODI). The cross-sectional areas of spinal canal were measured by CT scanning and were compared between pre- and post-operation. RESULTS: The average operative time was 47 minutes (range, 35-80 minutes); the average blood loss was 145 mL (range, 120-350 mL); and the average hospitalization days were 7.8 days (range, 4-15 days). Cerebrospinal fluid leakage occurred in 1 case, and healing of incisions by first intention was achieved in the others. The patients were followed up 12-22 months (mean, 14.8 months). CT scanning showed interspinous fusion in 14 cases and possible fusion in 2 cases after operation, with an average fusion time of 4.6 months (range, 3-10 months). The postoperative VAS score, ODI, and cross-sectional area were significantly improved when compared with preoperative values (P < 0.05). CONCLUSION: The ILIF can promote fusion between spinous processes, provide spine stabilization, and protect the spinal cord. The procedure has small incision, simple method of fixation and fusion.