Options and Results in Nerve Reconstruction of Elbow Flexion in Patients with Post-Traumatic Brachial Plexus Injury

If active elbow flexion must be reconstructed in brachial plexus lesions, the option of nerve reconstruction should always be considered first. Depending on the etiology, there are several possibilities for re-neurotization of the musculocutaneous nerve, such as intraplexual reconstruction from the C6 root, or extraplexual reconstruction from the accessory nerve, phrenic nerve, intercostal nerves, ulnar nerve, pectoral nerve, and contralateral C7 root.

Between 1981 and 1999, 1300 post-traumatic brachial plexus lesions were treated. In 100 patients with a minimum follow-up of 3 years, the results of nerve reconstruction of active elbow flexion using C6+ 3 nerve grafts (n = 50), half an acessory nerve + nerve graft (n = 12), phrenic nerve (direct coaptation on the anterolateral aspect of the upper trunk; n = 3), 3 intercostal nerves (direct coaptation; n = 20), 3 intercostal nerves + nerve graft (n = 10), ulnar nerve (FCU; n = 3), and dorsal root of contralateral C7 + vascularized nerve graft (n = 2) were evaluated. Criteria used were muscle power ( MRC classification) and time to recovery. Successful elbow flexion was achieved if muscle power > M3.

A successful elbow flexion, i.e. muscle power > M3, was achieved after intraplexual neurotization from the C6 root in 45/50 patients. After extraplexual neurotization from the acessory nerve (9/12), from the phrenic nerve (3/3), from the intercostals directly onto the MC nerve (15/20), from the intercostals + nerve grafts (6/10), the FCU portion of the ulnar nerve (3/3) and the contralateral C7 root (2/2), distal extraplexual neurotization using part of the ulnar nerve showed the most rapid, and intercostal transfer showed the slowest recovery rate.

Providing adequate muscle organ function, active elbow flexion can be reconstructed in 60 to 90% of patients. If possible, the MC nerve should be grafted from the C6 root. However, in cases of poor root quality or avulsion distal to neurotization, the phrenic and portions of the ulnar nerve were of great value. Because of low donor-site morbidity, the ulnar nerve should be considered more often.

Active elbow flexion is necessary for manual work. Knowing the different possibilites for nerve reconstruction and secondary tendon transfer should make reconstruction of active elbow flexion possible in almost every partial brachial plexus lesion and in most complete brachial plexus lesions.