Radial Clubhand Workup

Updated: Apr 20, 2018
  • Author: Scott H Kozin, MD; Chief Editor: Harris Gellman, MD  more...
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Laboratory Studies

The appropriate workup for associated conditions necessitates referral to pediatric subspecialists. [5] The heart is evaluated by means of auscultation and echocardiography. The kidneys are examined by means of ultrasonography, and the platelet status is assessed by means of blood count and peripheral blood smear.

The most devastating associated condition is Fanconi anemia. Children with Fanconi anemia do not have signs of bone marrow failure at birth; therefore, the diagnosis is not initially apparent. The majority of children experience signs of aplastic anemia between the ages of 3 and 12 years (median age, 7 years). However, a chromosomal challenge test is available that allows detection of the disease before the onset of bone marrow failure. This assay subjects a sample of the child’s lymphocytes to diepoxybutane or mitomycin C, which cause chromosomes within Fanconi anemia cells to break and rearrange. In contrast, lymphocytes in unaffected children are stable to these agents.

Because bone marrow transplant is the only cure for Fanconi anemia, this prefatory diagnosis is crucial for the child and family. Early diagnosis provides ample time to search for a suitable bone marrow donor or consider preimplantation genetic diagnosis (PGD). PGD is a sophisticated technique that involves in-vitro fertilization, sampling of the blastocytes to ensure human leukocyte antigen (HLA) similarity without Fanconi disease, and reimplantation until birth. At delivery, cord blood is harvested from the newborn and used as a source of stem cell transplant to the affected sibling.

Since PGD takes time, early detection via a chromosomal challenge test is critical and may ultimately save the affected child. The pancytopenia can be treated with bone marrow transplantation, but even with these efforts, life expectancy is only estimated at 30 years (range, 0-50 years).


Imaging Studies

Plain radiographs are obtained to evaluate the degree of radial aplasia and to assess associated abnormalities of the elbow, wrist, and hand (see the image below).

Radiograph of type IV deficiency with complete abs Radiograph of type IV deficiency with complete absence of radius.

In radial clubhand, ossification is delayed, and final determination of complete aplasia of the radius or carpus must be deferred until later (up to the age of 8 years).