Pronator teres rerouting in children with cerebral palsy

Purpose: The forearm in children with cerebral palsy often assumes uncontrolled dynamic positioning in pronation when the hand is put into use. This hypertonic positioning seems to be an expression of dystonia rather than spasticity. This article reports the effect of pronator teres rerouting (PTR) using the technique of tendon Z-lengthening and repair on active motion and on forearm positioning during use. Methods: Thirty-one patients who had pronator teres rerouting were observed before and after surgery for active and passive forearm range of motion, changes in dynamic forearm positioning, and the performance of 5 functional tasks related to forearm rotation. The primary indication for surgery was pronation positioning of 250 or greater because that positioning precludes grasping a glass or cup of water. Results: The follow-up period averaged 39 months. The average active supination increased 65 degrees, and the average dynamic positioning changed from 26 degrees pronation to 7 degrees pronation. Thirty of the 31 patients gained the ability to hold a cup of water in the involved hand. Nine children positioned the hand in supination during grasp. Conclusions: Pronator teres rerouting improves both active supination and dynamic forearm positioning in children with cerebral palsy. The use of the technique described in the literature resulted in slight overcorrection of forearm positioning in the nine children. This finding is consistent with the concept that positioning disorders are at least partly dystonic rather than spastic. It is recommended that the transfer be tensioned more loosely in children who have excessive dynamic hypertonia.