Radial Longitudinal Deficiency (Radial Club Hand)

What is radial longitudinal deficiency (radial club hand)?

Radial longitudinal deficiency is a rare condition that affects the forearm. It is a congenital condition, meaning your baby was born with it, and can affect one or both arms. It is sometimes called radial club hand, radial dysplasia, or radius deficiency.

There are two bones in your baby’s forearm: the ulna, on the outer side of the arm, and the radius, on the inner side. Radial longitudinal deficiency occurs when the radius does not form properly. This causes the wrist to bend toward the thumb side of the forearm.

Radial longitudinal deficiency also affects the soft tissues and flesh of the forearm. The arrangement of muscles and nerves may be unbalanced, and some muscles and nerves may be missing.

What are the symptoms of radial longitudinal deficiency?

If your child has a mild form of radial longitudinal deficiency, the condition will probably not cause problems with their development or hand movement.

If your child has a severe form, they may have problems moving their hand, fingers, and elbow. Their entire arm will be shorter, with a curved forearm and stiff elbow and fingers. They may also have a small or missing thumb.

A typical arm compared to four types of radial longitudinal deficiency. Type 1 is the least severe type and type 4 the most severe. In type 1, the radius (the bone on the inside of the forearm) is slightly shorter than the ulna (the bone on the outside of the forearm). In types 2 and 3, the radius is significantly shorter than the ulna and the hand curves inward. In type 4, the ulna is completely missing. The thumb tends to be smaller in more severe types.

Types of radial longitudinal deficiency

  • Children with type 1 radial longitudinal deficiency can move their hand normally. They usually do not need surgery unless it is necessary to correct an underdeveloped thumb.
  • In children with type 2 radial longitudinal deficiency, the wrist bends inward, and the ulna bows out. Children with this type often have an underdeveloped thumb.
  • Children with type 3 radial longitudinal deficiency are missing most of the radius bone. The wrist bends inward more severely and the hand has limited support. The ulna is bowed. Most children with this type of radial longitudinal deficiency have an underdeveloped or missing thumb.
  • Type 4 radial longitudinal deficiency is the most common and most severe form of radial longitudinal deficiency. Children with this type are missing the radius bone and have significant shortness in the forearm. They may also have limited range of motion in their elbow. Most children with type 4 have an underdeveloped or missing thumb, and may have differences in their other fingers as well. Many children adapt by using their pinky finger to pick up toys and other objects.

What causes radial longitudinal deficiency?

Radial longitudinal deficiency usually occurs by chance, although for some people it can also run in the family. Doctors and scientists do not know why some children are born with this condition. There are several theories, including compression of the uterus and blood vessel injury. None of these theories have been proven, however.

There are no known links between this condition and the mother’s lifestyle or anything the mother may do during pregnancy.

Radial longitudinal deficiency is associated with several congenital syndromes, including those affecting the heart, digestive system, and kidneys. It has also been linked to some chromosomal abnormalities, including Down syndrome and Trisomy 18 and 13.

How we care for radial longitudinal deficiency at Boston Children’s Hospital

The Orthopedic Center’s Hand and Orthopedic Upper Extremity Program and our the Department of Plastic and Oral Surgery’s Hand and Reconstructive Microsurgery Program have treated thousands of babies and children with radial longitudinal deficiency and other hand problems. We are experienced treating conditions that range from routine to highly complex and can provide your child with expert diagnosis, treatment, and care. We also offer the benefits of some of the most advanced clinical and scientific research in the world.

Our Orthopedic Center is nationally known as the preeminent center for the care of children and young adults with a wide range of developmental, congenital, neuromuscular, sports-related, traumatic, and post-traumatic problems of the musculoskeletal system.

Our Department of Plastic and Oral Surgery is one of the largest and most experienced pediatric plastic and oral surgery centers anywhere in the world. We provide comprehensive care and treatment for a wide variety of congenital and acquired conditions, including hand deformities.