Reherniation and failure after lumbar discectomy: a comparison of fragment excision alone versus subtotal discectomy.

STUDY DESIGN: Retrospective review of 259 lumbar discectomies.

OBJECTIVE: To compare rates of reoperation after subtotal discectomy versus established rates after fragment excision.

SUMMARY OF BACKGROUND DATA: Herniated nucleus pulposes (HNP) and annular morphology influence rates of reherniation after discectomy. Certain patterns are linked to reherniation rates exceeding 20%.

METHODS: We retrospectively reviewed 259 single-level lumbar discectomies performed between 1980 and 2005. Mean follow-up was 60.9 months. In each case, annulotomy and subtotal discectomy was performed in addition to excision of disc fragments. HNP morphology was classified according to the 4-part system of Carragee (type 1: fragment/fissure; type 2: fragment/defect; type 3: fragment/contained; type 4: no fragment/contained). Fisher exact test was used to compare our proportion of patients with reherniation and/or reoperation to Caragee's series in which only fragment excision was performed.

RESULTS: Of 259 cases, 12 (4.5%) reoperations were performed. A significant difference in failure/reoperation rate was noted in type 2 herniations. There was a significantly lower rate of failure and reoperation for type 2 HNP after subtotal discectomy (3.4%) when compared with fragment excision alone (21.2%), P<0.003.

CONCLUSIONS: Subtotal discectomy is an acceptable technique that decreases reherniation after lumbar discectomy.