OUTCOME AFTER REPEAT LUMBAR MICRODISCECTOMY

One of the standard treatments for herniation of lumbosacral disc mate rial has become the microdiscectomy. Although multiple studies have as sessed the outcome of microdiscectomy, only a few studies have evaluat ed the outcome of those patients who have undergone a second microdisc ectomy at the same location as the original one. The purpose of this s tudy was to review 55 patients who, over a 4-year period, underwent a second microdiscectomy at the same location as their original operatio n and to evaluate those factors associated with improved outcomes. The results showed the overall outcome to include 86% with complete or pa rtial relief of all pain symptoms; 88% with complete or partial relief of sciatica; 85% with complete or partial relief of back pain; 100% r eturning to work in an average of 7 weeks; and 89% were glad they had the second operation. Those factors without predictive value included age, sex, weight, height, level of operation, side of operation, surge on at the first or second operation (e.g. consultant or junior staff), length of the first operation ( less than or equal to 60 min or > 60 min) and duration of symptoms before the first operation. The key feat ures centred on preoperative job status, the interval between recurren ce of symptoms and the second operation, and the duration of the secon d operation ( less than or equal to 90 min). Those with the most favou rable outcomes fell into a bimodal distribution of the time between op erations ( < 6 or > 24 months) suggesting that earlier evaluation and repeat microdiscectomy upon return of symptoms may prevent development of the long-term effects of nerve root injury and also limit the prog ressive negative psychosocial aspects of chronic pain syndromes.