A controlled trial of anterior spinal fusion and débridement in the surgical management of tuberculosis of the spine in patients on standard chemotherapy: a study in Hong Kong

Abstract

One hundred and fifty Hong Kong patients with a diagnosis of tuberculosis of the thoracic or lumbar spine were allocated at random to operation by radical resection of the spinal lesion and insertion of autologous bone grafts (Rad. series) or by simple débridement of the spinal focus (Deb. series). All the patients were treated with isoniazid plus PAS for 18 months and daily streptomycin for the first 3 months. The main analysis of this report concerns 64 Rad. and 66 Deb. patients with less than 3 vertebral bodies destroyed. The clinical and radiographic condition of the two series on admission was similar. In 60 of the Rad. and 63 of the Deb. patients the allocated operation was successfully completed; in the remaining 4 Rad. and 3 Deb. it had to be repeated or a different operation performed. All the Rad, patients and only 4 Deb. patients were treated in plaster beds, the mean period of recumbency in bed being 73.2 and 11.2 days respectively. Twenty per cent of the Rad. patients and 12 per cent of the Deb. patients had a clinically evident abscess and/or sinus initially; all had resolved by 18 months. Of 22 Rad. and 20 Deb. patients with a radiographically evident mediastinal abscess initially and who at no time had a sinus or clinically evident abscess, the shadow had disappeared in 19 and 9 respectively by 12 months, in 19 and 17 respectively by 24 months and was still present in 3 and 1 respectively at 36 months. The mean total vertebral loss on admission was 0.7 in each of the series; at 36 months there was a mean gain of 0.2 of a vertebra in the Rad. series and a mean further loss of 02 of a vertebra in the Deb. series (P< 0∼001). The mean angulation of the spine at the start of treatment was 23.0o for the Rad. and 16.40for the Deb. patients. The mean increase over the 3 years was 0.90 for the Rad. and 4.50 for the Deb. patients (P = 0.1). Radiographic evidence of bony fusion of the affected vertebral bodies had occurred in 31 per cent of 55 Rad. and 3 per cent of 58 Deb. patients at 6 months (P = 0.0001), in 89 and 53 per cent respectively at 18 months (P< 0.0001)and in 93 and 69 per cent respectively at 36 months (P = 0.003). At 18 months 89 per cent of the Rad. and 79 per cent of the Deb. patients had a favourable response to the originally allocated treatment. The corresponding percentages at 3 years were 87 and 86per cent. However, if the response was classified irrespective of any additional chemotherapy or additional operation received, the proportions with a favourable response increased to 97 and 95 per cent respectively. Biopsy specimens from spinal lesions were obtained at operation in 149 patients. In 127 (85 per cent) the specimens were histologically tuberculous andlor yielded positive cultures for tubercle bacilli. The organisms were resistant to one or more of the three standard drugs in 24 of 108 strains but the influence on the results was minor.