Elbow dislocations occur when the lower end of upper arm bone (humerus) loses contact with the tops (heads) of the forearm bones (radius and ulna). Elbow dislocations may be complete (the ends of the bones do not touch) or partial (part of the bones still touch). Partial dislocations are called subluxations.
Complete elbow dislocations are uncommon and usually result from great force. Partial elbow dislocations (subluxations) are common among toddlers and usually result from much less force. Subluxations occur in but are much less common among infants, older children, and adults.
This injury typically occurs in toddlers (about 2 to 3 years old). In toddlers, the head of the radius (the larger forearm bone) is small enough to slip through the ligaments that hold the elbow in place. The head of the radius can slip through the ligaments when a parent or other caregiver pulls a reluctant toddler forward or catches the toddler by the wrist during a fall—actions many caregivers do not remember. As children grow, the head of the radius enlarges, so that eventually, the head of the radius is too big to easily slip out of place.
The joint may be only mildly tender. Because toddlers usually cannot describe their symptoms, the only sign of this injury may be unwillingness to move the arm. The arm may dangle down by the side of the body, sometimes turning slightly inward. Or toddlers may hold the arm in a bent position against their body. Parents or other caregivers should not try to move the arm.
Toddlers may cry when the injury happens but then calm down and continue to act normally except that they do not use the injured arm.
If toddlers have symptoms that suggest elbow subluxation, parents or other caregivers should take them to a doctor, even if the elbow slips back into place on its own.
Doctors suspect this injury based on the description of how it happened, symptoms, and results of a physical examination.
X-rays do not show the injury and so may not be taken.
Doctors usually attempt to put the joint back in place (called reduction). Usually, no sedatives or pain relievers are needed. When the bone is slipped back in place, a soft pop or click may be heard. Toddlers may start to move their elbow after about 10 to 20 minutes. If they do not move it, doctors may take x-rays of the elbow. If toddlers move the joint, the joint does not need to be immobilized.
If after 24 hours toddlers continue to have pain or if they still cannot use their arm, the joint may not be completely in place or a bone may be fractured. In such cases, toddlers should be seen by a doctor again.
With treatment, most toddlers recover completely. However, 20 to 40% of these children dislocate their elbow again.