Predictors of outcome in back surgery candidates

This study employed a prospective design to examine the value of three demographic, three orthopaedic, and four psychometric variables as predictors of orthopaedic and rehabilitation outcome in 116 Workers' Compensation patients seriously considered for first lumbar surgery, separately for the 74 who eventually did undergo surgery, and the 42 who did not. The two groups differed only with respect to the number of Nonorganic Physical Signs, but a complex pattern of predictive relationships emerged, in which orthopaedic outcome was generally easier to predict than rehabilitation outcome. Among the demographic factors, level of English proficiency was the best predictor and correlated positively with orthopaedic outcome in both surgery and non-surgery cases and with rehabilitation outcome in non-surgery patients. The Nonorganic Physical Signs test emerged as the predictor of choice and correlated with orthopaedic outcome in both groups and with rehabilitation outcome in the non-surgery group. Scale 1 of the MMPI correlated with orthopaedic outcome in both groups and Scale 3 with both orthopaedic and rehabilitation outcome, but only in the non-surgery patients.