Cystic changes in the acetabulum means that you have evidence of degenerative arthritis in the area where your hip connects to your femur. The acetabulum is the socket or cup-shaped part of the hip joint. Cysts can occur in bone just beneath the layer of cartilage that attaches to the bone. This is what is commonly referred to as a subchondral (literally meaning "beneath the cartilage") bone cyst. The exact cause of these cysts is not clear. One theory is that secondary to mechanical stress on the joint, the cartilage begins to tear. This leads to synovial fluid (joint fluid) entering the area. This leads to the formation of a cyst in the area of the hip joint. This finding is often referred to by radiologist as "cystic changes in the acetabulum."
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