Musculoskeletal infection with M tuberculosis accounts for 1–5% of cases of tuberculosis (TB) and can produce spondylitis (Pott disease), arthritis, osteomyelitis, tenosynovitis, bursitis, and pyomyositis. In developing countries, where the prevalence of TB is high, musculoskeletal TB remains an important source of morbidity and mortality, particularly among children. In the developed world, musculoskeletal TB is uncommon and largely affects adults. Immigrants from countries where TB is prevalent account for a substantial proportion of musculoskeletal TB in the United States and Europe. Musculoskeletal infection has been reported in HIV-infected persons and in patients whose TB reactivated in the setting of anti-tumor necrosis factor therapy. Tuberculosis is a reportable disease and suspected or proven cases should be reported to local public health authorities.
Spinal Tuberculosis (Pott Disease)
- Back pain.
- Radiographic evidence of spondylitis or spondylodisciitis.
- Identification of M tuberculosis in aspirates or biopsy specimens of skeletal lesions.
Tuberculosis of the spine accounts for approximately 50% of musculoskeletal TB. The thoracic and lumbar vertebrae are most often affected; the cervical spine is involved in less than 10% of cases. Organisms reach the vertebrae either by hematogenous spread (at the time of initial infection or during reactivation) or through lymphatic spread from renal, pleural, or other foci of disease. Most patients do not have active TB at sites outside the skeleton. Pulmonary TB, which is the most common form of concomitant extraskeletal disease, occurs in less than 20% cases.
Infection usually begins within the body of a vertebra and then extends to involve adjacent vertebrae and disks; however, “skipping” to noncontiguous vertebrae is not rare. Soft-tissue involvement is common, and paravertebral cold abscesses develop in about 75% of cases. Isolated involvement of the posterior elements is unusual (5% in one large series).
The most common presenting complaint is pain localized to the spine. The pain typically is not relieved by rest and may be present for months or longer before the patient seeks medical attention. In contrast to pulmonary TB, constitutional symptoms (weight loss, fever, and night sweats) occur in only 50% of cases.
Radicular pain is common. Approximately 50% of patients have lower extremity weakness at presentation; these figures are higher in case series from the developing world. Compression of either the cauda equina or the spinal cord by an inflammatory mass or abscess is the leading cause of neurologic compromise. Meningitis and meningomyelitis are less common. Severe spinal instability can lead to compression or ischemia of the cord.
Destruction of the anterior vertebral body can result in severe angular kyphosis: the gibbus deformity of Pott disease. Paravertebral cold abscesses can track from the lumbar vertebrae along the psoas muscle and present as inguinal masses or can extend from the thoracic spine ...