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Nursemaid Elbow
Definition:
This injury is commonly found in children under school age, usually aged between one and three. Nursemaid elbow describes a condition where two of the three bones of the elbow joint have become displaced. The medical term for this injury is radial head subluxation. The term nursemaid elbow comes from when women had to carry heavy milk buckets. Now, workers such as baggage handlers are more vulnerable to this sort of injury. In children, girls tend to suffer from this condition more than boys, and the left arm is usually the injured limb.
The humerus (upper arm bone) meets the radius and the ulna (the two bones of the forearm) to form the elbow joint. The way the bones fit together allows the joint to move in a hinge-like manner and the forearm to rotate enough to turn the hand palm up or palm down. Surrounding and supporting the bones are ligaments, strong elastic bands of connective tissue that help to hold the bones in their correct positions.
The joint between the humerus and the ulna (the ulna runs down the little finger side of the forearm) is strong and not easily disrupted. The joint between the humerus and radius (bone on the thumb side of the forearm) is more dependent on a tight ligament (the annular ligament) to keep the head of the radius properly located. The radial head is slightly concave. In a toddler or young child, it shallowly encircles a rounded part of the distal (far) end of the humerus called the capitellum. As the child grows, the radial head becomes wider, forming a lip that encloses the capitellum more completely and makes the joint more secure. The shallow joint in a small child is coupled with a loose annular ligament that is vulnerable to tearing.
This arrangement in a child’s elbow means that the annular ligament is able to shift over the radial head when a particular pulling movement is made. The specific movement requires the forearm to be slightly rotated when the pulling force is exerted on the elbow. The ligament can then get trapped between the head of the radius and the capitellum.
As a child’s ligaments become stronger with time, the likelihood of suffering this injury decreases. Nursemaid elbow is not often diagnosed in children over the age of six.
Causes:
A sudden jerk, or repeated pulls, on the arm can tear the fibers of the ligament, weakening it enough so that the radius slips out of position. One common cause of nursemaid elbow is swinging a child by its arms. It might also occur by grabbing a child’s arm to prevent a fall, or lifting the child from the ground. Tugging along a recalcitrant toddler by the hand can also cause the injury. Nursemaid elbow is, in fact, sometimes called temper tantrum elbow. Occasionally an infant can suffer this injury by rolling over awkwardly and trapping the arm. The mechanism is that an adult holds a child by the wrist or hand and exerts a sudden, strong tug. An adult is much stronger than a child, and the annular ligament responsible for holding a child’s radius in position is a relatively weak structure. Adults are often unaware that innocently pulling on a child’s arm can cause such damage.
Symptoms:
- Crying with pain at the moment of injury
- Refusal to use the injured arm
- The child will usually cradle the injured arm against the body, elbow slightly bent and the palm facing down. If the arm is held in this position, the child often does not show any signs of pain.
- Pain felt if the forearm is rotated so that the palm faces up
- Pain sometimes felt in the wrist and shoulder (described if the child is old enough to talk)
- Possible tenderness over the elbow, but no swelling or bruising
- After the injury the child will normally seem unchanged except for the refusal to use the injured arm
Diagnosis:
You should seek immediate medical attention for this injury. An untreated subluxation can result in permanent loss of function in the elbow. With treatment, nearly every case results in a complete recovery. Either see your doctor or visit the emergency department. Nursemaid elbow is a partial dislocation injury and the bones can be easily and quickly repositioned in a procedure known as reduction.
You will be asked about the circumstances of the injury and the symptoms your child has been displaying or describing. Your child’s shoulder, elbow, and wrist will be physically examined. The doctor will be looking for areas of tenderness or other injuries. X-rays do not show soft tissues such as ligaments, but may be taken to rule out a bone fracture. A fracture might be suspected if there is bruising or significant swelling around the elbow.
Treatment:
Treatment for nursemaid elbow is to reduce the subluxation, that is, to reposition the bones properly within the elbow joint. The child will sit on a lap and the doctor will hold the straight arm in a particular way and then bend it suddenly and precisely. The bones will click back into place. This will probably cause brief pain to the child, but it is a very quick procedure taking a matter of seconds and normally provides complete pain relief as soon as it is done. Occasionally it may have to be attempted more than once. If the dislocation cannot be successfully reduced, X-rays may be taken to look for a bone fracture. In many instances the reduction then happens while the technician is positioning the arm ready for the X-ray. Sometimes a splint may be temporarily placed on the arm and a reduction attempted later. Often, the elbow will have spontaneously reduced itself by the time of the follow-up appointment.
Surgery is rarely needed for nursemaid elbow, and may only be considered if the child suffers from repeated incidents. Any surgery would be aimed at tightening up the annular ligament. A cast to completely immobilize the elbow while the ligament heals would probably be tried first.
Prevention:
Pulling strongly and sharply on a child’s arm can cause nursemaid elbow, so prevention consists of avoiding such movements. Lift your child by holding him or her under the armpits. After one incidence of nursemaid elbow a child is more likely to suffer from it again, particularly during the first few weeks after the initial injury, so especial care must be taken.
Never lift a child by one arm only. If you want to swing your child around in circles, do not hold onto the hands or wrists, but support your child under the arms and hold the upper body close to yours.
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