Long-term results of microsurgical treatment of lumbar spinal stenosis by unilateral laminotomy for bilateral decompression.

OBJECTIVE: Laminectomy and bilateral laminotomy are the standard procedures for decompression of lumbar spinal stenosis (LSS). With the aim of less invasiveness and better preservation of spinal stability, the technique of unilateral laminotomy for bilateral decompression (ULBD) was developed. However, limited follow-up data exist to determine the efficiency and outcome of ULBD. Therefore, the authors present their 10-year experience with ULBD and postoperative long-term results.

METHODS: One hundred thirty-three consecutive patients (73 men and 60 women; mean age, 63 yr) meeting clinical and radiographic criteria for LSS who underwent first-time ULBD between 1994 and 1999 entered the study. The study parameters were set to ensure a follow-up period of at least 4 years. All patients were available for short-term follow-up re-evaluation within 3 months, and 102 (77%) of the 133 patients were available for long-term examination after a mean duration of 5.6 years. The scale of Finneson and Cooper was used for evaluation of the clinical results.

RESULTS: One hundred thirty patients (97.7%) improved immediately after surgery. Ninety-four (92.2%) of the 102 patients available for long-term follow-up examination remained improved, and 85.3% had an excellent-to-fair operative result. The incidence of complications was 9.8%. Resurgery for complication was necessary in three patients, for restenosis in seven patients, and for spinal instability in two patients, accounting for a reoperation rate of 11.8%.

CONCLUSION: ULBD allows achievement of good and long-lasting operative results in patients with LSS. Postoperative deterioration, recurrences, and spinal instability are infrequent. For the authors, ULBD is the preferred technique to treat symptomatic LSS.