What would you do? Case challenges in knee surgery.

These knee arthroplasty cases were presented to a panel of surgeon and they represent classic clinical problems: (1) indications for unicompartmental arthroplasty; (2) total knee arthroplasty after a high tibial osteotomy complicated by infection and extensor mechanism rupture; (3) neuropathic arthropathy; (4) posttraumatic osteoarthritis with extraarticular deformity; (5) degenerative arthritis in the young patient; (6) osteoarthritis with a valgus deformity, fixed flexion contracture, degenerative scoliosis, and leg length discrepancy.