Summary Radial Clubhand is a rare birth defect characterized by a deformity of hand, with perpendicular relationship between forearm and wrist, and an absent thumb. Diagnosis is made on physical exam. Treatment may be observation or surgical reconstruction when the child is around 6 months of age. EPIDEMIOLOGY Incidence rare 1 per 100,000 anatomic location bilateral in 50-72% thumb usually deficient as well Etiology Genetics likely related to sonic hedgehog gene Associated with TAR autosomal recessive condition with thrombocytopenia and absent radius different in that thumb is typically present Fanconi's anemia autosomal recessive condition with aplastic anemia Fanconi screen and chromosomal breakage test to screen treatment is bone marrow transplant Holt-Oram syndrome autosomal dominant condition characterized by cardiac defects VACTERL Syndrome vertebral anomalies, anal atresia, cardiac abnormalities, tracheoesophageal fistula, renal agenesis, and limb defects) VATER Syndrome vertebral anomalies, anal atresia, tracheoesophageal fistula, esophageal atresia, renal agenesis) Classification Bayne and Klug Classification Type I Deficient distal radial epiphysis Type II Deficient distal and proximal radial epiphyses Type III Present proximally (partial aplasia) Type IV Completely absent (total aplasia - most common) Presentation Physical exam deformity of hand with perpendicular relationship between forearm and wrist absent thumb perform careful elbow examination Imaging Radiographs entire radius and often thumb is absent Laboratory must order CBC, renal ultrasound, and echocardiogram to screen for associated conditions Treatment 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