Clinical manifestations of type IV ulna longitudinal dysplasia.

PURPOSE: Ulna longitudinal dysplasia is an uncommon congenital anomaly that demonstrates a wide variety of clinical manifestations. The clinical manifestations and function of patients with Bayne type IV ulna longitudinal dysplasia have not been well characterized. The purpose of this study was to report the clinical features of type IV ulna longitudinal dysplasia and the extent to which this affects a patient's ability to perform activities of daily living.

METHODS: The medical records of children diagnosed with ulna longitudinal dysplasia in our institution between 1960 and 2004 were reviewed. The children found to have ulna longitudinal dysplasia with radiohumeral synostosis (Bayne type IV ulna dysplasia) were studied. The laterality of the deformity, associated musculoskeletal and nonmusculoskeletal anomalies, and treatments were recorded. Patients were interviewed regarding their ability to perform activities of daily living.

RESULTS: One hundred twenty-five patients with 146 affected limbs were identified with ulna dysplasia. Seventeen limbs in 14 patients (12% of affected limbs) demonstrated radiohumeral synostosis (RHS). Three of 14 patients with RHS had bilateral involvement. The elbows were fixed in 20 degrees to 90 degrees of flexion. No elbows were positioned in full extension. Eleven of the 17 involved limbs with RHS had digital anomalies. Nine of the 17 limbs had surgical reconstruction. The majority of these procedures were performed on the hand.

CONCLUSIONS: The elbow, forearm, wrist, and hand clinical findings associated with type IV ulna longitudinal dysplasia are variable. Surgical treatment usually focuses on correction of hand abnormalities. Many patients function satisfactorily and are able to perform daily activities without surgical intervention.