Proximal Tibiofibular Joint Arthritis Co-existing With a Medial Meniscal Tear: A Case Report.

Proximal tibiofibular joint (PTFJ) arthritis is rare and, thus, not regularly considered as a source of knee pain. In this report, we present the case of a patient with posterior knee pain attributed to a medial meniscal tear rather than to a co-existing PTFJ arthritis, which was not appreciated. Based on the initial diagnosis, the patient underwent knee arthroscopy that did not alleviate his symptoms. The presence of established tibiofibular joint arthritis was diagnosed on subsequent clinical and MRI reassessment. An intra-articular corticosteroid injection settled the patient's symptoms. The aim of this report is to raise awareness about tibiofibular joint arthritis as a possible cause of posterior or lateral knee pain.