We report the case of an 11-year-old child who presented with knee pain and moderate limp associated with knee flexum, without trauma history. Radiographic investigations including a magnetic resonance imaging showed a large cyst that seemed to have developed anteriorly from the anterior cruciate ligament, causing the loss of terminal extension, mimicking a cyclops syndrome-like of the knee. Knee arthroscopy with debridement of the cyst was performed, and the patient quickly recovered his range of motion. Histological analysis confirmed a synovial cyst in accordance with arthroscopic and radiological findings.
This case is interesting because of the rare occurrence of ganglion cysts in children.