This study evaluates the degree of objectively quantified physical deconditioning of spinal surgery patients. The object is to evaluate the data in terms of the pain and disability claimed by 35 male and 11 female patients three months after spinal surgery. Among the males, two subgroups (i.e., disc excision or spinal fusion) were evaluated. All patients reported subjective indices of pain/disability and completed quantified tests of lumbar motion, sagittal trunk strength, lifting capacity, and bicycle ergometry. In general, true lumbar motion was markedly restricted to 50%-60% and trunk strength means were below 50% of gender-specific normative values. There were similar deficits for lifting capacity. Those who had spinal fusions tended to perform poorly, with a relatively high incidence of pain/disability. There were no differences found between the male group and subgroups who were gainfully employed or had a brief period of disability prior to surgery or had low subjective pain/disability. These results indicate that a patient's subjective pain/disability were not a reliable measure of functional capacity by three months postoperatively. Regardless of working status, pain level, or brevity of disability, there was a significant loss of performance ability and risk of persistent dysfunction after surgical treatment.