Tuberculosis of navicular bone: An exceptional localization of osteoarticular tuberculosis

Osteoarticular tuberculosis (OAT) is defined by the set of pathological manifestations secondary to the attacks of osteoarticular structures of the locomotor system by the Bacillus of Koch (BK). We report a case of tuberculosis of the navicular bone, which is a rare location of OAT, on a female patient who consulted for chronic pain (mixed appearance) evolving for more than 7 years and for whom we realized a radiological assessment based on standard radiography and magnetic resonance imaging and a biological assessment. The foot is rarely involved, accounting for about 10% of cases of osteoarticular tuberculosis. The diagnosis is often made at a late stage because osteoarticular tuberculosis is paucibacillary, and it is difficult to isolate or culture Koch's bacillus. Clinical manifestations are aspecific; pain and joint swelling are the 2 usual signs. Pain may be mechanical, inflammatory, or mixed. The standard radiography allows first to orient the diagnosis by the demonstration of a lytic process; a biological inflammatory syndrome and the magnetic resonance imaging allow to give more arguments in favor, then the biopsy comes to confirm the diagnosis. Tuberculosis of the navicular bone is a rare localization of OAT; its diagnosis is the same as well as the treatment.