Distal Humerus Fracture
A distal humerus fracture is the term used to describe a type of elbow fracture where the lower end of the upper arm bone (humerus) has been broken. It is a relatively uncommon injury in adults, accounting for only about 2% of fractures. Children are more likely to suffer this type of injury.
Three bones articulate with each other to form the elbow: the humerus in the upper arm, and the radius and ulna in the lower arm. Together they allow the arm to move in a hinge-like manner, and also to turn the hand palm up or palm down. The way the bones are shaped keeps the elbow joint in its correct alignment, with a cup-shaped part of the ulna (olecranon) holding the end of the humerus and moving around it as the elbow bends. Muscles and tendons cause movement and ligaments run from bone to bone, helping to maintain alignment and prevent excessive mobility.
The humerus can often break into several pieces when it is broken at the distal end. This is known as a comminuted fracture. Fractures are named and graded according to location and severity. Due to the structure of the elbow and the associated muscles, nerves, and blood supply, a distal humerus fracture can be challenging to treat.
A strong impact, such as during a motor vehicle accident, or falling and landing on the point of the elbow, are common causes of a distal humerus fracture.
Another type of fall that produces such a fracture is when the elbow is straight and the person lands on the outstretched arm. In this instance it is possible for the ulna to be forced into the humerus, breaking it.
Fractures from falls are more likely to happen to elderly people, while fractures from a blow happen more often to younger people.
- Severe pain on impact
- Pain so severe that the patient is unable to move the elbow at all
- Swelling, bruising, and tenderness of the elbow
- Rarely, the fracture may be compound, meaning that a piece of bone has pierced the skin
- The elbow will feel extremely unstable and vulnerable
- Occasionally numbness or tingling may be felt in the wrist or hand
The doctor will ask for a medical history, including any previous injuries to the elbow. The elbow will be physically examined. The entire arm and shoulder may be examined at the same time, to rule out other injuries. The examination will include checking the skin for abrasions or lacerations. If the broken bone has pierced the skin there is a real risk of infection. The doctor will gently palpate (touch) the entire elbow area to determine if there might be other injuries, such as another broken bone, or a dislocation of the elbow. Blood flow to the hand and fingers will be checked, and the patient will probably be asked to move the fingers. This is because there is a nerve (radial nerve) that can be damaged during this sort of injury. For the same reason, the patient will probably be asked if he or she feels any numbness or tingling. It is unlikely that the patient will be able to straighten the elbow when asked by the doctor.
X-rays will be taken of the elbow. X-rays show bones in great detail so are very useful if a distal humerus fracture is suspected.
Initial treatment is to place the arm in the correct position for healing and immobilize the elbow in a splint or brace. The splint will be worn for at least a week, but possibly up to six weeks. Pain medication will be administered.
The need for surgery will depend on whether or not the humerus has been displaced. If the bone is still in its correct position treatment may consist of continuous wearing of the splint and sling for several weeks, with regular follow-up appointments with the doctor and further X-rays.
Many distal humerus fractures require surgery to reposition the humerus or to reassemble pieces of broken bone. Fixation devices such as orthopedic pins, screws, and plates are often used to hold the bones in position during healing. Compound fractures will always need surgery.
Regardless of whether surgery was performed or not, physical therapy is necessary to rehabilitate the elbow. The patient will be advised when to start, with the probable recommendation to work with a physical therapist. An exercise program would be developed beginning with gentle range of motion exercises, followed by strengthening exercises once the bone was fully healed. These exercises would have to be done several times a day. An elbow fracture and the required time in a splint results in considerable stiffness in the elbow, so the patient would have to be prepared for a lengthy period of rehabilitation. Regaining as much use of the elbow as possible requires dedication to the physical therapy aspect of recovery.
The outcome of having sustained a distal humerus fracture depends on the severity of the fracture and the patient’s willingness to adhere to the exercise program. It is likely that, for some patients, full healing may take over a year, although many people can return to their normal activities within about four months. Residual stiffness in the elbow will gradually improve with use, and strength return. It is likely that for some people complete straightening of the elbow will no longer be possible, but the difference is usually small and most people do not find that the loss of extension is a problem.
A rare occurrence is the growth of extra bone around the joint. This can impede movement of the elbow and will require later surgery to remove the extra bone. Further physical therapy would be necessary following the surgery.
Arthritis in the elbow is a fairly common consequence of a distal humerus fracture. This will not necessarily hinder use of the elbow, or be painful.
Any nerve damage sustained during the fracture normally improves with time.
A hinged elbow brace is often the most appropriate brace for a distal humerus fracture. This can initially be fixed at a 90% angle, then gradually regulated to allow the elbow to begin flexing and extending a little more with each adjustment.