A locked knee, or, Locking of the knee joint may occur when a loose fragment wedges itself between the joint surfaces. Loose fragments which may be found in the knee joint are loose cartilage fragments, cartilage fragments with attached bone (osteochondral fractures) and unstable meniscal tears.
An acutely locked knee is one of the indications for early arthroscopy after knee injury. Loose fragments must be removed and treated on their merits. A meniscal tear may be debrided or repaired, an osteochondral fragment may be replaced and fixed with countersunk screws or glue or the fragment may be removed.
One of the controversial issues is whether associated injuries such as ACL disruption are addressed at the early arthroscopy or whether the knee is left to settle down before those definitive procedures are carried out.
Cartilage defects may be managed with various techniques, depending on their size and severity.
