A prospective investigation into the orthopaedic and psychologic predictors of outcome of first lumbar surgery following industrial injury.

One hundred sixteen patients randomly selected by officers (authors excluded) of the Workers' Compensation Board of Ontario were studied over a 3-year period. The selection criteria used were no previous back surgery and first back operation now scheduled. The purpose was to establish a battery of clinical and psychologic tests to be used in arriving at a prognosis for preoperative patients. The tests included orthopaedic examination, 10-minute Hendler questionnaire, nonorganic component assessment, psychologic interview, Minnesota Multiphasic Personality Inventory, pain drawing, locus of control, McGill Pain Questionnaire. The most striking of the many computer results obtained was an 82% prognosis success rate. The five predictor variables that most significantly predicted outcome were English proficiency, the nonorganic signs test, back pain versus leg pain, hypochondriasis scale of the MMPI, and the pain drawing.