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.

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.

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.

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.

• Nonoperative

  • passive stretching

    • target tight radial-sided structures

  • observation

    • indicated if absent elbow motion or biceps deficiency

      • hand deformity allows for extra reach to mouth in presence of a stiff elbow

• Operative

  • hand centralization

    • indications

      • good elbow motion and biceps function intact  

      • done at 6-12 months of age   

      • followed by tendon transfers

    • contraindications

      • older patient with good function

      • patients with elbow extension contracture who rely on radial deviation

      • proximate terminal condition

    • technique

      • involves resection of varying amount of carpus, shortening of ECU, and, if needed, an angular osteotomy of the ulna (be sure to spare ulnar distal physis)

      • may do as two stage procedure in combination with a distraction external fixator

      • if thumb deformity then combine with thumb reconstruction at 18 months of age