Case: Three weeks after transphyseal anterior cruciate ligament reconstruction with a hamstring autograft, a fourteen-year-old boy presented with fevers, joint effusion, and elevated inflammatory markers. Cultures from an operative debridement grew Mycobacterium fortuitum, for which he received six months of antibiotics. Continued drainage prompted magnetic resonance imaging, which revealed osteomyelitis of the tibial tunnel.
Conclusion: This case report describes a postoperative infection with an atypical organism that had a protracted course despite early diagnosis. Complete resolution was achieved following tibial tunnel debridement with a high-speed burr and bone-grafting with an antibiotic-laden allograft.