TUBERCULOUS LESIONS OF THE LUMBOSACRAL REGION - A 15-YEAR FOLLOW-UP OF PATIENTS TREATED BY AMBULANT CHEMOTHERAPY

Study Design. A 15-year clinical follow-up of tuberculous lesions of t he lumbosacral region. Objectives. To verify the hypothesis that the l umbar lordosis and the specific biomechanics of the lumbosacral region influence and alter the healing pattern and progress of the disease w hen compared with their effects in other regions of the spine. Summary of Background Data. An estimated 2 million or more patients have acti ve spinal tuberculosis, and the global incidence of the disease is inc reasing. The involvement of the lower lumbar region and the lumbosacra l junction is relatively rare, with few reports in English literature. Methods. Of a total of 304 patients forming a part of a controlled cl inical trial comparing two forms of therapy in spinal tuberculosis, 53 patients had involvement of L3 and below. The following data were stu died in these patients: age at start of treatment, number of vertebra involved, vertebral body loss, progress of the angle of kyphosis, and anterior and posterior growth of the involved segment during a period of 15 years. Student's t test for independent samples was used for sta tistical analysis. Results. The fourth lumbar vertebra was the most co mmon vertebral segment involved, and the lumbosacral junction was affe cted in 12 patients. The average pretreatment kyphosis was 6.4 degrees and increased to 10.2 degrees at the end of 15 years. The average kyp hotic angle per vertebral body loss was 4.9 degrees, far less than in the dorsolumbar region in which kyphotic angles of 27-30 degrees have been reported. Children younger than 10 years old differed in clinical appearance and progress compared with those older than 17 years. They not only showed more extensive involvement but also had more deformit y with the same vertebral loss, Twelve patients less than 10 years old had an average involvement of 3.1 vertebral bodies and an average ver tebral loss of 2.2 bodies, In comparison, the average number of verteb rae involved was 1.9 (P < 0.01) and the vertebral body loss was only 0 .87 (P < 0.01) in patients older than 17 years. Also, the average kyph osis was 6.4 degrees compared with only 4.2 degrees (P < 0.01) in adul ts. In patients older than 17 years, there was no change after 2 years , by which time the collapse was complete. Four of 12 patients less th an 10 years old, showed progressive kyphosis caused by continued growt h of posterior parts of the body (i.e. sequestrated hemivertebrae). Co nclusions. In tuberculosis of the lumbosacral region, the development of kyphosis is minimal in patients older than 17 years, when growth ha s already stopped, and deformity is expressed more as foreshortening o f the trunk. Children younger than 10 years old have more severe invol vement with increased tendency toward greater kyphosis. They are also prone to progressive deformity through the years when the anterior gro wth plates are destroyed. Surgery is indicated in this group to preven t greater deformity.