Lumbar disc herniations: the predictive value of the Health Attribution Test (HAT) and the Minnesota Multiphasic Personality Inventory (MMPI).

Ninety-one patients who were treated for lumbar disc herniation with chymopapain chemonucleolysis were evaluated preoperatively by means of the Health Attribution Test (HAT) and the Minnesota Multiphasic Personality Inventory (MMPI). There were 54 good, 10 fair, and 27 poor results after chemo-nucleolysis. Nineteen patients subsequently underwent lumbar laminectomy and discectomy and the ultimate outcome for the entire series including these laminectomy patients was 66 good, 10 fair, and 15 poor results. The fair/poor chemonucleolysis outcome patients scored significantly lower than did the good outcome patients on the HAT Powerful Others and significantly higher on the Chance scale. Patients with fair or poor outcomes after chemonucleolysis only scored significantly higher on the Hypochondriasis, Hysteria, Psychopathic Deviate, Paranoia, and Hypomania scales in preoperative MMPI testing. Good versus fair/poor ultimate outcome patients differed significantly on preoperative MMPI Hypochondriasis, Hysteria, Psychopathic Deviate, Paranoia, Psychasthenia, Schizophrenia, Hypomania, and Social Introversion scales. These groups also differed significantly on preoperative HAT Internal and Chance scales. Further analyses found the MMPI to be a slightly better predictor of chemonucleolysis outcome and much better predictor of ultimate outcome than the HAT.