[Treatment of knee joint arthritis in the middle-aged patient].

Degenerative arthritis of the knee joint is a common problem of the middle-aged patient. Primary arthritis has to be distinguished from secondary disease caused by malalignment, instability or trauma. The key symptom is pain at the jointline on weight-bearing. Diagnosis is established from history, clinical and radiological examination. Treatment options are chosen depending on the severity of symptoms and the demands of the patient. They range from modification of sports- and recreational activities, nonoperative therapy to operative options such as resecting arthroscopic procedures, repair of damaged articular cartilage, osteotomy and unicompartmental knee arthroplasty. However, the patient has to be made aware that a cure for this disease remains to be found.