A proximal humerus fracture is a break in the long bone of the upper arm at the shoulder joint. In a young person, this kind of a break can happen after a severe trauma to the shoulder. More commonly, a proximal humerus fracture may occur after an older person with osteoporosis takes a fall.
During bone development, four growth plates form at the end of the humerus at the shoulder joint. These plates are originally made of cartilage and they give the bone flexibility and allow it to grow in length. As the humerus bone reaches maturity, the growth plates solidify into bone. They are, however, susceptible to fracture if the patient takes a fall and lands on her open hand.
The injured patient would usually have pain and swelling in the shoulder following a proximal humerus fracture. Patient history and a description of the fall or trauma would give the physician an indication of a fracture. X-rays at several different angles would be needed to confirm the diagnosis. A computed tomography (CT) scan could also be done to give a better view of the fracture.
Growth plates of the humerus divide the proximal end at the shoulder into four parts: the humoral head, the greater tubercle, the lesser tubercle, and the diaphysis or shaft. Most fractures of the proximal humerus are considered nondisplaced, which means that none of these four sections have been separated by more than 0.39 inches (1 cm). Nondisplaced fractures are usually treated by immobilizing the arm in a sling for 7-10 days. This allows gravity to keep the humerus in the correct location. Healing of the bone should begin in three to six weeks.
If any of the four end regions of a shoulder fracture are separated by more than 0.39 inches (1 cm), this is referred to as a displaced fracture. Displaced fractures are categorized as two-part, three-part, or four-part fractures. In a two-part fracture, two different parts of the end region of the humerus would have been displaced.
Most two- and three-part fractures are treated surgically. The surgeon may perform an open reduction, which means that an incision is made in the shoulder and the bone fragments are reduced or put back in their original location. Bone fragments are then secured in place with pins, screws, or plates.
Severe four-part fractures also need to be treated surgically, but the surgeon may choose to perform a hemiarthroplasty. A hemiarthroplasty is a procedure in which the shoulder joint is replaced by an artificial metal joint that extends into the hollow space in the center of the humerus. The joint is then sutured to the bone to hold it in place.
Physical therapy is an important part of healing following a proximal humerus fracture. Range of motion exercises are usually started two weeks after surgery. For complete healing, the patient will need to be committed to therapy and work closely with the physician.