Fifty-six adults (average age, 38 years) with active tuberculosis of the lumbar and lumbosacral spine were treated conservatively with triple chemotherapy for 12 to 18 months. The minimum followup was 3 years. Three methods of assessments of the chronologic changes of sagittal spinal deformity were used on lateral radiographs of the lumbar spine obtained with the patient standing: deformity, kyphos angles, and total lumbar lordosis. The lumbosacral joint angle was measured for tuberculosis of the lumbosacral joint. The disease healed in all patients with a minimum increase of kyphosis, although in 23 patients there was minimal new involvement of the adjacent vertebral bodies within 6 months of treatment. The pattern of the involved vertebral body collapse in tuberculosis of the lumbar and lumbosacral joints was vertical (telescoping), along a longitudinal axis that minimized the progression of kyphosis. The outcome was judged on the basis of residual kyphosis (British Medical Research Council criteria) and found to be favorable in 96.4% (54 patients). Triple chemotherapy for lumbar and lumbosacral tuberculosis is effective in curing the disease and in minimizing the residual kyphosis through early diagnosis and immediate initiation of chemotherapy. The pattern of vertebral body collapse is the telescoping type, which is the determining factor in minimizing residual spinal deformity.