38 year old guy fired his 45 mm into his knee while cleaning the gun. No exit wound.

There is a comminuted fracture of the distal femur with multiple bullet fragments, including the largest at the intercondylar notch. There is gas/air in the knee joint, forming air-fluid levels on lateral view. There are additional foci of gas in the surrounding soft tissues.

Patient underwent arthrotomy for foreign body removal and fixation of the supracondylar/intercondylar femoral fracture.