Radial longitudinal deficiency is a spectrum of malformation affecting the radial side of the forearm, i.e. radius, radial carpus, and thumb.

The spectrum includes hypoplasia of the bone and joints, muscle and tendons, ligaments, nerves, and blood vessels.

It is also called a radial club hand.

The incidence of radial longitudinal deficiency is 1 in 50,000 to 1 in 100,000 live births.

Radial longitudinal deficiency occurs as an isolated disorder or associated with a recognized malformation syndrome.

The molecular basis of isolated radial longitudinal deficiency is still unknown.

Syndromes associated with radial longitudinal deficiency are Holt-Oram syndrome, Fanconi anemia, TAR syndrome, VACTERL syndrome, and Trisomy 13 & 18. Other causes include fetal alcohol syndrome, maternal exposure to the drug such as valproic acid, thalidomide, phenobarbitone, and aminopterin.

Radial longitudinal deficiency affects both genders equally.

Bilateral affection is seen in 50% of the cases when the deformity is unilateral; the right side is more commonly affected.

Presentation varies from severe manifestation to subtle finding.

The subtle finding may be noticed incidentally on a radiograph as a mild hypoplastic thumb and missing or fused carpal bones.

Severe manifestation includes the total absence of radius, deficiency of the proximal part of the upper limb with a short humeral segment, and hypoplastic glenoid.

The complete absence of radius is more common than partial absence.

Clinically visible deformities are as follows –

Short forearm

Radial deviation of the wrist

Hypoplastic or aplastic thumb

Stiffness of finger

Radiographs are essential to classify the deficiency and to follow up. Radiographs {Posteroanterior view and neutral rotation} will show the degree of involvement of the radius, carpus, and thumb.

Spine radiographs, renal ultrasound, complete haemogram, and echocardiography are required to assess the associated anomalies.

Stretching and splinting should be started in early infancy to maintain soft tissue length.

Surgical treatment is needed to achieve the maximum potential of a child in selected cases.

Basic goals of the treatment are as follow –

Correct the radial deviation of the wrist

Balance the wrist on the forearm

Maintain wrist and finger motion

Promote the growth of the forearm

Reconstruction of thumb deficiency

Improve the function of the extremity

Timing of surgical intervention as follows –

6 to 12 months – Realigning and stabilizing the hand/carpus on the distal ulna

6 months after wrist realignment – Thumb reconstruction

By 18 months – Complete the reconstruction

Contraindications for surgical intervention are –

Life-threatening problems in other organ systems

Ulnohumeral synostosis – When active elbow flexion is absent, then wrist motion is needed to bring the child’s hand to the mouth.

Bilateral affection – Because bilateral centralization often worsens function and is rarely advised.

Children with the radial longitudinal deficiency will have a short forearm, recurrence of deformity if not splinted properly or incomplete correction is achieved.

It is difficult to achieve near-normal limb in severely affected radial longitudinal deficiency however, a subtly affected individual will lead a normal life.