VARIANT OF HOFFA DISEASE: A CASE REPORT This report presents the case of an 18-year-old female student with a low BMI, who was otherwise healthy. She presented with chronic anterior right knee pain persisting for 1 year. The pain began spontaneously and gradually increased in severity, especially during long distance walking and standing for more than 15 minutes. The symptoms did not subside with medication and physiotherapy. All biochemical and radiological investigations to rule out other related possible aetiologies were unremarkable. The patient eventually underwent an arthroscopic knee surgery, during which the intraoperative findings revealed the Hoffa fat pad over the anteromedial knee joint. This was debrided and after surgery, she was symptom free and had resumed her normal activities.

Locked knee is an orthopaedic condition requiring urgent treatment. Although the condition can be diagnosed via history, physical examination and imaging studies, the cause of the mechanical obstruction may only be apparent during arthroscopic examination of the knee joint. It is known that imaging plays a role in evaluating the integrity of intra-articular structures, however in some atypical cases, imaging cannot identify the definitive cause of locked knee. Here we report on two cases of locked knee, due to uncommon conditions which were unobservable via normal imaging studies.