A high proportion (43%) of patients with venous TOS exhibited CC, OD, and a previously undetected FRFx, including 76% of those over the age of 30. These lesions occur in the cartilaginous anterior rib where they are clinically occult and undetected by standard radiographic imaging. We postulate that age-related CC may predispose to OD and stress-induced FRFx, and that inflammation, fibrosis, and anatomic distortion in the surrounding soft tissues may contribute to SCV compression.