Chronic anterior knee pain following a direct injury to the front of the knee is common. The persistent symptoms can be troublesome. There is a paucity of documentation regarding its definition, natural history and prognosis. We have reviewed 46 (92%) of a consecutive series of 50 patients with chronic traumatic anterior knee pain, in which other significant acute knee pathology was excluded. After a mean follow-up of 4 years and 8 months only 4% of patients were pain free, 68% had moderate or severe pain and 28% mild pain. Twenty percent felt they were improving, 59% were static and 17% were deteriorating. The commonest clinical findings were patello-femoral crepitus (96%), local tenderness (72%) and difficulty in squatting or kneeling (72%). Few patients improve beyond 2 years and continued improvement is unlikely. In patients referred for specialist advice this is a clinical syndrome characterised by persistent debilitating symptoms resistant to treatment.