Loose bodies may be responsible for blocking sensation or pain in the hip. The causative agent can be the synovial osteochondromatosis, Perthes disease, the osteochondritis dissecans and trauma (hip dislocation - Pimpkin fracture). The loose particles may be removed arthroscopically, without the need for open surgery.
Loose body in the peripheral compartment (arrow). (JC: joint capsule, AL: acetabular labrum, FH: femoral head)