Atypical extraspinal musculoskeletal tuberculosis in immunocompetent patients, a review. Part I: atypical osteoarticular tuberculosis and tuberculous osteomyelitis.

With the resurgence of pulmonary tuberculosis and musculoskeletal tuberculosis in North America and Europe over the last 20 years, the typical pattern of extraspinal musculoskeletal tuberculosis has been changing; presentation of the disease often mimics that of neoplasia. However, certain radiographic features may offer some clues to the more benign nature of the process and its inflammatory and infectious nature. Although the diagnosis of extraspinal musculoskeletal tuberculosis depends largely on clinical context, it is the radiologist's role to guide the imaging workup to initiate the specific treatment as early as possible. As in classic extraspinal tuberculosis, delayed diagnosis may lead to deformity of the involved joint and permanent disability. This review considers atypical osteoarticular tuberculosis and tuberculous osteomyelitis. We discuss examples of these atypical presentations. All patients were permanent residents in Europe and North America, and all were immunocompetent.