Department of hand surgery & Microsurgery.

Ulnar Longitudinal Deficiency

What is Ulnar Longitudinal Deficiency ?

Ulnar longitudinal deficiency (ULD) is also known as ulnar club hand.Our forearm has two bones in it ; namely radius and ulna. The bone in line with the thumb is radius and the bone in line with the little finger is ulna.

In general, there are five types of thumb hypoplasia or aplasia:

It is a rare congenital condition where the ulna bone in the forearm does not form properly. A congenital condition means that it existed at birth or even before birth. ULD causes the affected hand to be bent outwards toward the little finger side of the forearm, often with limited movement.

In addition to the curve of the wrist and forearm, 90% of children have missing digits, 30% have fused fingers and 70% may have problems with the thumb.The severity is different in each child.

How common is it ?

It is an uncommon condition. Incidence is approximately 1 in 1,00,000 live births.

Cause of Ulnar Deficiency

A baby’s arms form between four and eight weeks of pregnancy, sometimes before a woman even knows she is pregnant. By eight weeks the arms are fully formed, although tiny.

Due to unknown reasons they may not form normally. With hand differences, the genetic changes generally occur for no apparent reason. Less commonly, genetic changes run in families.

Some hand abnormalities have no known cause. In some cases, the hand difference is an isolated event. In other cases, the difference is part of a syndrome that affects multiple parts of the body.

Problems Associated with Ulnar Deficiency

Ulnar Deficiency is most commonly seen with other musculoskeletal anomalies, including proximal femoral focal deficiency, fibular deficiency, phocomelia and scoliosis.

Diagnosis of Ulnar Deficiency

ULD can sometimes be seen on a routine prenatal ultrasound. After the baby is born, it is easily identified, and the diagnosis is usually confirmed through a physical exam and X-rays. When diagnosing the condition, your child’s doctor may classify it as one of four types − with type 1 being the mildest and type 4 the most severe.

Ulnar Deficiency Treatment

The main goal and benefit of treatment is to improve the child’s ability to function with the condition. Another aim is to improve the appearance of the hand and support the child’s self-esteem.

Treatment varies depending on the complexity of the condition and may include:

  • Stretching
  • Splinting or casting
  • Physical therapy (to help increase strength and function)
  • Prosthetics (in the case of missing parts or bones)
  • Surgery

If surgery is the chosen course of treatment, the goal is usually to realign and stabilize the hand and wrist. The timing of the surgery would depend on:

  • The patient’s age and overall health
  • The type and extent of the condition
  • The ability to tolerate treatment
  • The way the condition is expected to progress

In most cases, surgery is done before the child reaches school age but generally not before 6 months of age. In all cases, the goal of surgery is to repair any associated abnormalities, and improve range of motion and function.

Recovery varies from one week to several months, depending on the extent of the surgery. Most patients can return to normal activity within three to six weeks of surgery. However, three months is often required for complete recovery.