Of 112 patients who were subjects of the Medical Research Council's prospective study, 105 (94%) were involved in a longitudinal study follow-up for a mean of 15.3 years postoperatively. Seventy-one patients had radical resection of the tuberculous lesion and bone grafting, and the remaining 34 were treated with debridement surgery at a mean age of 36.7 and 35.3 years, respectively. All these patients were aged 18 years or older at the time of surgery. The kyphosis and deformity angles were measured on lateral spinal radiographs using an electronic digitizer. The results can be summarized as follows: (1) Neurologic recovery in both radical and debridement surgical groups were equally good and no patient had pain two years after surgery. There was no incidence of reactivation or recurrence of tuberculosis in either surgical group. (2) At the six-month postoperative evaluation, patients who had radical surgery showed marginal correction in deformity, whereas those who were treated with debridement showed deterioration in both kyphosis and deformity angles. There was a statistically significant difference between the two surgical groups for the mean changes in kyphosis and deformity angles at the six-month postoperative evaluation compared with their preoperative evaluation. (3) The mean difference for kyphosis and deformity angles at final follow-up evaluation from the patients' six-month postoperative measurements were not statistically significantly different between the two surgical groups. (4) Forty percent of patients showed an improvement in deformity angle by 5 degrees or more after radical surgery at the six-months postoperative evaluation, whereas 53% of patients showed deterioration after debridement surgery. (5) All patients with tuberculosis of the lumbar spine treated with radical surgery had normal lordosis in the lumbar spine at final follow-up evaluation, compared with only 63% of patients after debridement surgery. Correction achieved after surgery at the six-month evaluation was practically maintained up to final follow-up evaluation. Radical resection and bone grafting provided better correction of deformity than did debridement surgery.