الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The most common mechanism of injury in a proximal humerus fracture is trauma to the arm or shoulder, such as occurs with a fall onto an outstretched hand. Fractures of the proximal humerus usually involve the humeral shaft, surgical neck, or the sites of muscle attachment (greater or lesser tuberosities). Fractured bones may remain in alignment (nondisplaced fracture) or fragments may separate and become misaligned (displaced fracture). Displaced fractures most commonly involve the surgical neck of the humerus. The degree of fracture displacement is dependent upon the direction of pull of the muscles that attach to the tuberosities. Greater tuberosity fractures account for 15% of proximal humerus fractures, and are associated with anterior shoulder dislocations one-third of the time. Shoulder dislocation may occur with proximal humeral fracture (fracture-dislocation).Athletes and older individuals, particularly post-menopausal women with osteoporosis, are at greater risk of sustaining proximal humerus fractures. Among younger individuals, high-impact sports activity is a frequent cause. Proximal humerus fractures are twice as common in women as in men, largely due to the increased incidence of osteoporosis in women.Proximal humerus fractures account for 5% of all fractures. Incidence increases with age. Proximal humerus fracture is a major cause of morbidity in individuals age 65 and older..