Forearm Synostosis Using A Vascularized Pedicled Ulnar Periosteal Graft for Supination Deformity in Brachial Plexus Birth Injury

Background

Forearm supination posture is a common secondary deformity in brachial plexus birth injury (BPBI), leading to functional impairment of the upper limb, as pronation is required for most activities of daily living. The purpose of this report is to analyze a series of children with forearm supination deformity secondary to severe BPBI and complete pronation palsy, who were treated with forearm fusion in slight pronation through the creation of a radioulnar synostosis using a novel distal pedicled vascularized ulnar periosteal flap (VUPF).

Methods

Retrospective analysis. Inclusion criteria included complete pronation paralysis with active wrist extension present and a minimum of 6 months follow-up. Demographic information, preoperative passive pronation, postoperative forearm rotational position, radiographic union, and parental satisfaction using a 4-point Likert-type ordinal scale (1-very unsatisfied, 2-unsatisfied, 3-satisfied, and 4-extremely satisfied) were analyzed. A retrograde distally pedicled vascularized ulnar periosteal flap covering approximately one third of the ulnar length and based on the posterior interosseous vessels—was transferred to the dorsal aspect of the radius and fixed for 4 weeks using Kirschner wires.

Results

Twenty children with a mean age of 53.6 months (range 20 to 115 months) and a mean passive forearm pronation of 9° (range 60° to 60°) with a mean follow-up of 13.7 months (range 8 to 18 months) were included in this report. All except one had complete residual BPBI. A partially ossified radioulnar synostosis was radiographically observed at 4 weeks in all cases. Mean immediate postoperative and final follow-up rotational values were similar, measuring 15° of pronation (range 0° to 30°). All parents reported extreme satisfaction with both functional and cosmetic outcomes.

Conclusions

Forearm fusion in slight pronation by creating a radioulnar synostosis using a distal pedicled vascularized ulnar periosteal flap is an effective and fast technique to correct supination deformity and might be considered among other reported strategies.