Restoration of prehension with the double free muscle technique following complete avulsion of the brachial plexus - Indications and long-term results

Background: Recent interest in reconstruction of the upper limb following b rachial plexus injuries has focused on the restoration of prehension follow ing complete avulsion of the brachial plexus. Methods Double free muscle transfer was performed in patients who had compl ete avulsion of the brachial plexus. After initial exploration of the brach ial plexus and (if possible) repair of the fifth cervical nerve root, the f irst free muscle, used to restore elbow flexion and finger extension, is tr ansferred and reinnervated by the spinal accessory nerve. The second free m uscle, transferred to restore finger flexion, is reinnervated by the fifth and sixth intercostal nerves. The motor branch of the triceps brachii is re innervated by the third and fourth intercostal nerves to restore elbow exte nsion. Hand sensibility is restored by suturing of the sensory rami of the intercostal nerves to the median nerve or the ulnar nerve component of the medial cord. Secondary reconstructive procedures, such as arthrodesis of th e carpometacarpal joint of the thumb, shoulder arthrodesis, and tenolysis o f the transferred muscle and the distal tendons, may be required to improve the functional outcome. Results: The early results were evaluated in thirty-two patients who had ha d reconstruction with use of the double free muscle procedure. Twenty-six o f these patients were followed for at least twenty-four months (mean durati on, thirty-nine months) after the second free muscle transfer, and they wer e assessed with regard to the long-term outcome as well. Satisfactory (exce llent or good) elbow flexion was restored in twenty-five (96 percent) of th e twenty-six patients and satisfactory prehension (more than 30 degrees of total active motion of the fingers), in seventeen (65 percent). Fourteen pa tients (54 percent) could position the hand in space, negating simultaneous flexion of the elbow while moving the fingers at least 30 degrees and coul d use the reconstructed hand for activities requiring the use of two hands, such as holding a bottle while opening a cap and lifting a heavy object. T he results were analyzed to identify factors affecting the outcome, Conclusions: The doable free muscle procedure can provide reliable and usef ul prehensile function for patients with complete avulsion of the brachial plexus.