In contrast to important functions of the proximal tibiofibular joint (PTFJ), there appear a few clinical and radiological studies concerning the PTFJ pathologies. Although almost all of the joints have been investigated in detail by MRI, review of the literature reveals none on the pathologies of PTFJ. Thirty-eight knees of 32 patients with lateral knee pain were evaluated clinically and radiologically. All had tenderness over the PTFJ and lateral hamstring tightness. MRI examination revealed effusion of the PTFJ in 22 knees and partial ruptures of anterior or posterior tibiofibular ligament, lateral collateral ligament or biceps femoris tendon in 25 knees. All patients were treated by manipulative physiotherapy of the PTFJ and strengthening and stretching exercises of the surrounding structures. All patients were followed-up 12-36 months (mean 28 months) after the treatment protocol, and complete relief of the symptoms was recorded in 28 of the 38 knees. Although spontaneous pain was not present in five patients, there was tenderness over the PTFJ by palpation. No change in the symptoms was recorded in five patients. These results suggest that PTFJ pathologies should be kept in mind in the evaluation of lateral knee pain and MRI examination provides useful information. (C) 2003 Elsevier B.V. All rights reserved.