Radial Longitudinal Deficiency

What is radial longitudinal deficiency?

Radial longitudinal deficiency happens when the radius bone in the forearm does not form correctly as a fetus develops. The forearm has two bones running through it: the radius, on the thumb side, and the ulna, on the pinky side. Radial longitudinal deficiency causes the wrist to bend toward the thumb side of the arm.

There are four types of radial longitudinal deficiency, and depending on the severity, children with the condition may be able to move their hand normally, or they may have difficulty moving their hand and arm, their thumb may be underdeveloped or missing, and their affected forearm may be shorter.

Radial longitudinal deficiency usually occurs randomly. It also can be associated with several other conditions that effect other organs, and some genetic differences.

How is radial longitudinal deficiency diagnosed?

Sometimes doctors can diagnose radial longitudinal deficiency on an ultrasound before birth. Other times it is noticed at birth. Doctors will examine your baby’s forearm and take an x-ray to help understand the severity of the condition. Doctors will also check for other syndromes that can go alongside radial longitudinal deficiency, which may involve blood tests and ultrasounds of the heart or kidneys.

How is radial longitudinal deficiency treated?

Most infants with radial longitudinal deficiency are first treated with gentle stretching exercises to help their wrist extend and their elbow move into a normal position. Your child’s doctor will show you how to perform these exercises at home. Depending on the severity of the condition, some infants will also need to wear a splint to slowly stretch their muscles.

More severe cases may also benefit from surgery after stretching and splinting. Stretching and splinting help make any future surgery more effective. We work with each patient and family to develop a surgical plan that is customized to every child’s unique needs. Different surgeries can help reposition and stabilize the wrist, forearm, thumb, and elbow, all designed to help improve range of motion and strength. Many children also benefit from occupational therapy as they get older to maintain their arm strength and function.