Various hip bone shapes, in addition to FAI, may be associated with bone impingement and pain. Although, not common, Ischio-Femoral Impingement can occur when the lesser trochanter of the femur is too close to the ischium of the pelvis, and crushes the normal muscle and tendon which lies between these two bones. This may lead to pain with walking and sometimes also a painful clunking. The condition is sometimes seen in Race Walkers due to the abnormal pelvic movements they develop to increase speed.
It may be possible to treat this condition with training to improve muscle strength and and hip mechanics.
If this is not successful, then the space between the bones can be increased to relieve the impingement. One such method is arthroscopic resection of the lesser trochanter.
Subspine impingement may occur when a prominent area of the pelvis immediately above the hip joint, the Anterior Inferior Iliac Spine (ASIS) impinges against the femoral neck during hip flexion. This condition may be caused by childhood injury, or may be developmental. The prominent area of bone can be removed arsthroscopically.