title: Survival analysis is a better estimate of recurrent disc herniation.
abstract: Studies on recurrent disc herniation quote rates of recurrence without regard to the times of recurrence and the influence of longer follow-up. Our objective was to assess the use of survival analysis to measure the rate of revision after lumbar microdiscectomy. We undertook a retrospective analysis of the hospital records of 993 patients who underwent lumbar microdiscectomy over a period of ten years. After calculating the overall rate of revision for the mean length of follow-up, we carried out a survival analysis using the life-table method. During the study period 49 patients had a revision microdiscectomy. This gave an overall rate of revision of 4.9% at a mean follow-up of 5.25 years. Using survival analysis, the rate of revision was 7.9% at a follow-up of ten years when the number at risk was 84. Survival analysis gives a more accurate estimation of the true rate of recurrence for patients undergoing lumbar microdiscectomy. The method allows better comparison between different interventions for disc herniation.
authors.affiliation: Department of Orthopaedic Surgery, Royal Berkshire Hospital, Reading, England, UK.
authors.forename: P
authors.initials: P
authors.lastname: Gaston
authors.forename: R W
authors.initials: RW
authors.lastname: Marshall
mesh_terms: D000328:Adult; D017586:Diskectomy / Q000379:methods; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000601:surgery*; D015993:Life Tables; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D012008:Recurrence; D012086:Reoperation; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome