Tubercular Osteomyelitis of Navicular Bone: A Rare Site for Bone Tuberculosis

Tuberculosis (TB) is a global public health problem, endemic to India. Osteoarticular TB uncommonly presents in the foot, navicular osteomyelitis is an extremely rare entity. We report a rare case of navicular osteomyelitis caused by TB in a 37-year-old man who presented to OPD with swelling and dull aching pain over the dorsum of his left foot. A radiograph of the foot showed a lytic lesion in the navicular bone. Further investigations in the form of aspiration cytology, cartridge-based nucleic acid amplification test, and acid-fast bacilli culture confirmed TB. Category-1 anti-tubercular therapy was started immediately and the patient was treated conservatively. Four drugs (HRZE) were given for 2 months and 3 drugs (HRE) for 9 months, after which the patient stopped his medications on his own. Radiographs and CEMRI at 14-month follow-up showed a healed lesion. This case illustrates an exceptional location of osteoarticular TB and shows that Navicular TB can be treated conservatively with near-complete function and recovery if diagnosed early.