Phrenic nerve transfer to the musculocutaneous nerve for the repair of brachial plexus injury: electrophysiological characteristics

Phrenic nerve transfer is a major dynamic treatment used to repair brachial plexus root avulsion. We analyzed 72 relevant articles on phrenic nerve transfer to repair injured brachial plexus that were indexed by Science Citation Index. The keywords searched were brachial plexus injury, phrenic nerve, repair, surgery, protection, nerve transfer, and nerve graft. In addition, we per-formed neurophysiological analysis of the preoperative condition and prognosis of 10 patients undergoing ipsilateral phrenic nerve transfer to the musculocutaneous nerve in our hospital from 2008 to 201 3 and observed the electromyograms of the biceps brachii and motor conduc-tion function of the musculocutaneous nerve. Clinically, approximately 28% of patients had brachial plexus injury combined with phrenic nerve injury, and injured phrenic nerve cannot be used as a nerve graft. After phrenic nerve transfer to the musculocutaneous nerve, the regener-ated potentials ifrst appeared at 3 months. Recovery of motor unit action potential occurred 6 months later and became more apparent at 12 months. The percent of patients recovering ‘ex-cellent’ and ‘good’ muscle strength in the biceps brachii was 80% after 18 months. At 12 months after surgery, motor nerve conduction potential appeared in the musculocutaneous nerve in seven cases. These data suggest that preoperative evaluation of phrenic nerve function may help identify the most appropriate nerve graft in patients with an injured brachial plexus. The func-tional recovery of a transplanted nerve can be dynamically observed after the surgery.

Bilateral musculocutaneous neuropathy:A case report

BACKGROUND Isolated musculocutaneous nerve injury is a rare condition.Herein,we report the first case of bilateral musculocutaneous neuropathy after vigorous stretching of both upper extremities with normal results of sensory nerve action potential.Clinicians should be aware of this rare condition that can appear bilaterally.In addition,the interpretation of the aberrant electrodiagnostic study results of this case was discussed.CASE SUMMARY A 29-year-old male complaining of bilateral forearm tingling and upper extremity weakness visited the outpatient clinic.The symptoms began 6 mo prior,and he visited another hospital before visiting our department.The diagnosis was not made even after cervical spine magnetic resonance imaging,electrodiagnostic study,brain magnetic resonance imaging,and arteriography were conducted.The patient performed unique exercises that stretched the pectoralis minor and coracobrachialis muscles.On the follow-up electrodiagnostic study,abnormal spontaneous activities in the bilateral biceps and brachialis muscles were observed.The patient was diagnosed with bilateral musculocutaneous neuropathy.Steroid pulse therapy was administered for approximately 6 wk.After treatment,his muscle strength returned to the predisease condition.CONCLUSION Clinicians should be aware of this condition,have adequate understanding of anatomy,and advise to correct inappropriate exercises.

Diagnosis and operative treatment of radiation-induced brachial plexopathy

To explore the diagnosis and operat ive treatment of radiation induced brachial plexopathy. Methods: Nine cases of radiation induced brachial plexopathy w ere divided into two groups, 4 cases undergoing neurolysis of brachial plexus as Group A and 5 cases undergoing transfer of myocutaneous flaps after neurolysis as Group B. In Group B, 4 cases were treated with latissimus dorsi myocutaneous flaps (about 20 cm×20 cm) and 1 case with pectoralis major myocutaneous flap (a bout 8 cm×6 cm). Results: All the 9 cases of radiation induced brachial plexopa thy were followed up for a period of 2 to 5 years, with an average of 2.3 ye ars. As far as pain relief and function recovery were concerned, the results of Group B were better than those of Group A. Conclusions: Based on the results of Group B in the series, we suggest that the procedure of covering the wounds with transferred myocutaneous flaps after neurolysis of the brachial plexus should be performed to those advan ced patients. The procedure may improve the blood supply of the fibrotic brachia l plexus by reestablishing a good nerve bed.