Isolated tuberculosis of posterior elements of spine - Magnetic resonance Imaging findings in 33 patients

Study Design. Study of magnetic resonance imaging (MRI) of tuberculosis of spine to determine the incidence and features of isolated tuberculous involvement of the posterior spinal elements. Objective. To describe the MRI findings in patients with isolated tuberculous involvement of the posterior spinal elements. Summary of Background Data. Spinal tuberculosis is more common in the eastern countries than in the western world. Recently, there has been a renewed interest in tuberculosis in the west because of its re-emergence, especially in immunocompromised patients (e.g., HIV). The classic radiologic picture of "two vertebral disease with the destruction of the intervertebral disc" is easily recognized and readily treated, but its atypical forms are often misdiagnosed and mistreated. Method. A total of 33 patients 13-53 years of age (16 men, 17 women; mean age 28.30 years) with proven tuberculosis of posterior element of the spine were retrospectively evaluated. The clinical and imaging data were studied in all 33 patients. Results. Involvement occurred from C2 to L5 vertebral levels. Most commonly, involvement was seen in the thoracic vertebrae (16 patients, 48.5%) followed by lumbar vertebrae (13 cases, 39.4%) and cervical vertebrae (4 patients, 12.1%). The laminae were most commonly involved (24 patients, 72.7%; 8 bilateral, 16 unilateral) followed by pedicles (20 patients, 60.6%; 6 bilateral, 14 unilateral), articular processes (19 patients, 57.6%; 5 bilateral, 14 unilateral), spinous processes (19 patients, 57.5%), and transverse processes (12 cases, 36.4%; 5 bilateral, 7 unilateral). Bone destruction and marrow changes were seen in all patients. Involvement of the entire posterior arch was seen in eight patients. A total of 23 patients revealed extraspinal soft tissue collections. Intraspinal extradural granulation tissue/abscess was seen in 11 patients. Spinal cord was either displaced or compressed in 15 patients, and abnormal high signal intensity intrinsic cord changes were seen in eight patients. Conclusion. In tuberculosis of the posterior element of the spine, MRI is extremely useful in evaluating the extent of involvement and response to therapy of isolated tuberculosis of posterior elements. Involvement of posterior elements due to tuberculosis is not so uncommon.