Abstract
Intra-osseous ganglia occurs in the subchondral bone adjacent to joint and involves the upper and lower end of tibia, the upper end of femur, carpal bones and acetabulum most frequently. Although the ganglion's pathogenesis is still uncertain, intramedullary vascular disturbance due to mechanical stress and repeated minor stress is considered as an important cause. We experienced a rare case of intra-osseous ganglia that arised in patella.
A 64-year-old female struck her left knee 10 years ago and had gonalgia after walking. A radiolucent lesion existed in her left patella. This lesion was diagnosed as intra-osseous ganglia at the operation and histological finding. Ganglion was localized in bone and there was no connection with the knee joint and the surrounding soft tissue. Avascular necrosis of bone was found near intra-osseous ganglia histologically. This finding suggests that a localized vascular disturbance is a cause of intra-osseous ganglia.
