LUMBAR IPSILATERAL REVISION DISCECTOMY: CORRELATION BETWEEN INTRA-OPERATIVE FINDINGS AND OUTCOMES. A RETROSPECTIVE ANALYSIS OF 201 LUMBAR IPSILATERAL REVISION DISCECTOMIES (LIRD)

Abstract

Aim: The aim is to correlate intra-operative findings such as epidural fibrosis (EF), size and type of disc fragment, lateral recess stenosis and dural tear with postoperative residual radiculopathy (RR) and residual low back pain (RLBP).

Material and Methods: 246 revision discectomies performed between January 1994 and June 2004 were considered, of which adequate records were available for 215 (201 ipsilateral and 14 contralateral). Of 201 LIRDs, 85 were at L5S1, 101 at L45, 10 at L5S1+L45, 3 at L34 and 2 at L23 level. Patients who had had fusion or instrumentation in addition to LIRD were excluded. For 201 LIRDs average follow-up was 18.5 months (range −1 to 96 months) and 100 LIRDs had a minimum of 12 months’ follow-up.

Results: Of the 179 first-time LIRDs, 65 (36.3%) had significant RR, 73 (40.8%) significant RLBP, 3 (1.7%) cauda equina syndrome, 2 (1.1%) infective discitis, and 1 (0.6%) foot-drop. Of the 21 second-time LIRDs, 15 (71.4%) had significant RR, 17 (81%) significant RLBP, 2 (9.5%) infective discitis and 1 (4.8%) cauda equina syndrome. EF was classified as abundant, moderate and scant. Incidence of RR and RLBP was proportional to amount of EF and size of hypertrophic scarred ‘disc’ bulge, but it correlated poorly with size of ‘soft’ disc prolapse. Lateral recess decompression in addition to LIRD did not significantly alter the incidence of RR and RLBP.

25 (12.4%) patients who had dural tear had worse results.

Conclusions: Large proportion of LIRDs result in significant residual symptoms. Second-time LIRDs have higher complication rates and even poorer outcomes.