Prognostic Factors Associated with Revision Operation of Spine

Lee, Kyu Yeol; Sohn, Sung Keun; Lee, Dae Hee

Abstract

STUDY DESIGN: Patients who had had revision operation were classified according to their outcome.
OBJECTIVES
Review a consecutive series of patients who had had a revision operation on the lumbar spine and determine which factors contributed to a successful outcome. SUMMARY OF LITERATURE REVIEW: The long-term rates of failure after primary operations of spine have been reported to be as high as 30 percents.
MATERIALS AND METHODS
Twenty three patients who had had a revision operation on the lumbar spine between September 1995 and February 1997, were analyzed which patients had been followed for a mininum of two years and were available to exclude a questionable malingering. All twenty three patients had had decompression and instrumented fusion. These patients were followed for an average of thrity-seven months(range, twenty-four to forty-five months). There were seventeen men and six women. The patients had had one or more previous operative procedures and an average of thirty-seven months(range, three months to 18 years) had been elapsed since the most previous operation. The average age at the time of revision was 44 years(range, 28 to 65 years). The operative results were classified according to three primary criteria 1) return to ordinary activity, 2) analgesics use, 3) subjective satisfaction of patient. The outcome was considered to be success if the patient had met the all these three criteria. With use of a chi-square analysis(level of significance, P<0.05), several factors were evaluated to be determined which were related to a successful outcome.
RESULTS
Statistical analysis revealed that the factors associated with a successful outcome were a younger age (P<0.02), fewer spinal levels operated on previously (P<0.05), a pain-free interval after index operation (P<0.01). We could detect no significant relationship between the outcome and gender, the number of previous procedures, the presence of preoperative neurological sign and intervals between the index operation and the revision.
CONCLUSION
These results suggest that the prognostic factors are useful to evaluate the successful outcome of the revision operationof spine.