Osteoarthritis is the most common form of arthritis, and femoroacetabular impingement (FAI) may damage the hip and contribute to arthritis, particularly in younger patients. The hip is a ball-andsocket joint with the ball located on the femur, or thighbone. At the end of the femur that connects to the hip, the femur narrows to form a neck of bone adjacent to the ball. FAI occurs due to an altered or suboptimal shape of the femoral neck. This leads to repetitive contact between the femoral neck and the tissue around the rim of the joint socket. The resulting physical stress can damage tissues, leading to degeneration of the socket rim and tearing of the cartilage that makes up the socket. Open surgical rocedures to correct FAI have been developed, but these procedures are highly invasive.