Shoulder joint Shoulder joint The shoulder joint (or glenohumeral joint from Greek "glene", eyeball, + -"oid", 'form of', + Latin "humerus", shoulder) is structurally classified as a synovial ball and socket joint and functionally as a diarthrosis and multiaxial joint. It involves articulation between the glenoid cavity of the scapula (shoulder blade) and the head of the humerus (upper arm bone). Due to the very loose joint capsule that gives a limited interface of the humerus and scapula, it is the most mobile joint of the human body. The shoulder joint is a ball and socket joint between the scapula and the
Humerus fracture include having a low bone mineral density, having impaired vision and balance, and tobacco smoking. A stress fracture of the proximal and shaft regions can occur after an excessive amount of throwing, such as pitching in baseball. Middle fractures are usually caused by either physical trauma or falls. Physical trauma to the humerus shaft tends to produce transverse fractures whereas falls tend to produce spiral fractures. Metastatic breast cancer may also cause fractures in the humerus shaft. Long spiral fractures of the shaft that are present in children may indicate physical abuse. Distal fractures usually occur as a result of