A controlled trial of six-month and nine-month regimens of chemotherapy in patients undergoing radical surgery for tuberculosis of the spine in Hong Kong. Tenth report of the Medical Research Council Working Party on Tuberculosis of the Spine.

Sixty patients in Hong Kong with a diagnosis of tuberculosis of the thoracic, thoraco-lumbar or lumbar spine were allocated at random to either a 6-month (6M) or a 9-month (9M) regimen of daily isoniazid plus rifampicin, supplemented in all patients by streptomycin twice a week for the first 6 months. All patients had the modified 'Hong Kong' operation of radical resection of the lesion and insertion of autologous bone grafts. After exclusions, the main analyses of this report concern observations for 3 years on 51 patients (25 6M, 26 9M). The clinical and radiographic condition of the two series on admission was broadly similar. At 18 months, 19 of the 25 6M and 22 of the 26 9M patients had a favourable status, achieved on the allocated regimen that is, they had no clinical evidence of active disease, in particular no sinus or clinically evident abscess and no central nervous system lesions; they were capable of full physical activity and radiographically the lesion was quiescent. At 3 years, 24 patients in each series had a favourable status. Of the remaining three patients, one (9M) was clinically favourable but his spinal lesion was reported not yet quiescent at radiographic assessment. The other two patients (one in each series) had a favourable status in every respect except that they had required modifications of the allocated regimen; both had had a sinus at the site of the operation scar requiring surgical excision, with additional chemotherapy in one (9M). These modifications apart, all 25 6M and 25 of the 26 9M patients had a favourable status at three years. A sinus or clinically evident abscess was present on admission in seven patients (5 6M, 2 9M) and had resolved by 3 months in all seven, although one patient (6M) developed a sinus at the operation site subsequently. A further four patients (1 6M, 3 9M) developed an abscess or sinus for the first time after the start of treatment, but all resolved within 6 months. Two patients (one 6M, one 9M) had a mild paraparesis and one (9M) a cauda equina lesion on admission; all had resolved by 9 months. Radiographic evidence of bony fusion of the affected vertebral bodies had occurred in 36% of 25 6M and 42% of 26 9M patients at 6 months, in 44% and 77% respectively at 9 months (P = 0.03), 68% and 88% respectively at 18 months and 100% in both series at 36 months.(ABSTRACT TRUNCATED AT 400 WORDS)