Intercostal Nerve Transfer in Management of Biceps and Triceps Cocontraction in Spontaneously Recovered Obstetric Brachial Plexus Palsy.

Abstract

Obstetric brachial plexus palsy is caused by traction during birth. Most patients regain useful function with spontaneous recovery. In some cases, cross reinnervation occurs between the biceps and triceps muscles. In these cases, smooth active motion of the elbow joint is impaired by simultaneous biceps and triceps muscle contraction. The biceps and triceps muscle cocontraction could be treated by botulinum toxin type A injection, tendon transfer of the triceps to biceps, and intercostal nerves transfer to the musculocutaneous nerve (MCN) or to the motor branch of the radial nerve to the triceps muscle. We present 16 cases (10 males and 6 females) with biceps and triceps cocontraction in spontaneously recovered obstetric brachial plexus palsy patients. They were treated by 3 intercostal nerves transfer to MCN without exploration of the remaining plexus. The mean age at surgery was 40.6 months (range, 24-65 months). Preoperative electromyography was done in all cases to confirm biceps and triceps cocontraction and to assess the contractile status of both muscles. The mean postoperative follow-up period was 51.7 months (range, 27-64 months). At the final follow-up, elbow flexion was graded 3 in 1 patient, grade 4 in 3 patients, grade 6 in 9 patients, and grade 7 in 3 patients using the 7-point Toronto scale. The mean active range of motion of the elbow (against gravity) increased from 38 degrees preoperatively (range, 0-75 degrees) to 96.8 °[Combining Ring Above] at the final follow-up (range, 60-140 degrees). Intercostal nerves transfer to MCN for management of biceps, and triceps cocontraction in spontaneously recovered obstetric brachial plexus injury is a good option with minimal morbidity and high success rate.