Ulna Growth Patterns After Soft Tissue Release With Bilobed Flap in Radial Longitudinal Deficiency

Centralization is commonly utilized for treating the severely deviated wrist in radial longitudinal deficiency (RLD). Individuals with RLD have congenital shortening of the ulna and previous studies have shown that traditional centralization, in particular with notching of the carpus, results in additional ulnar growth retardation. At our institution, we use a technique of soft tissue release with bilobed flap. We examined if this technique preserves the growth potential of the distal ulna, therefore, avoiding an additionally shortened forearm.

We retrospectively reviewed serial radiographs of 16 patients with 18 wrists who had at least 3 years of follow-up after a soft tissue release with bilobed flap. Radiographic lengths were measured using the method described by Heikel. Percentage of normal growth was calculated using normative data published by Maresh. Comparisons were made with preoperative, postoperative, and final follow-up studies.

The average length of follow-up was 9.2 years (range, 3 to 16.3 y) with an average age of 11.6 years (range, 5.2 to 17.5 y). The average age at the time of surgery was 27 months (range, 14 to 48 mo). A minimum of 3 radiographic studies were available for each subject. The average ulna length preoperatively was 63.9% of age-matched normal length (51.4% to 75.3%). The average ulna length at final follow-up was 61.9% of age-matched normal length (48.5% to 70.3%). The difference was not statistically significant. In addition, there were no distal ulnar physeal arrests.

Soft tissue release with bilobed flap does not affect ulna growth like traditional centralization procedures can. This procedure has previously been shown to retain motion and have similar recurrence rates to formal centralizations. Therefore, we advocate that it be considered more widely for use in patients with RLD and significant wrist deviation to maximize growth and improve hand position. Soft tissue release with bilobed flap can be safely used on young children and preserve ulnar growth.

Level IV-therapeutic.