Contralateral C7 to C7 nerve root transfer in reconstruction for treatment of total brachial plexus palsy: anatomical basis and preliminary clinical results

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>Contralateral C7 (CC7) nerve root has been used as a donor nerve for targeted neurotization in the treatment of total brachial plexus palsy (TBPP). The authors aimed to study the contribution of C7 to the innervation of specific upper-limb muscles and to explore the utility of C7 nerve root as a recipient nerve in the management of TBPP.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>This was a 2-part investigation. 1) Anatomical study: the C7 nerve root was dissected and its individual branches were traced to the muscles in 5 embalmed adult cadavers bilaterally. 2) Clinical series: 6 patients with TBPP underwent CC7 nerve transfer to the middle trunk of the injured side. Outcomes were evaluated with the modified Medical Research Council scale and electromyography studies.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>In the anatomical study there were consistent and predominantly C7-derived nerve fibers in the lateral pectoral, thoracodorsal, and radial nerves. There was a minor contribution from C7 to the long thoracic nerve. The average distance from the C7 nerve root to the lateral pectoral nerve entry point of the pectoralis major was the shortest, at 10.3 ± 1.4 cm. In the clinical series the patients had been followed for a mean time of 30.8 ± 5.3 months postoperatively. At the latest follow-up, 5 of 6 patients regained M3 or higher power for shoulder adduction and elbow extension. Two patients regained M3 wrist extension. All regained some wrist and finger extension, but muscle strength was poor. Compound muscle action potentials were recorded from the pectoralis major at a mean follow-up of 6.7 ± 0.8 months; from the latissimus dorsi at 9.3 ± 1.4 months; from the triceps at 11.5 ± 1.4 months; from the wrist extensors at 17.2 ± 1.5 months; from the flexor carpi radialis at 17.0 ± 1.1 months; and from the digital extensors at 22.8 ± 2.0 months. The average sensory recovery of the index finger was S2. Transient paresthesia in the hand on the donor side, which resolved within 6 months postoperatively, was reported by all patients.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>The C7 nerve root contributes consistently to the lateral pectoral nerve, the thoracodorsal nerve, and long head of the triceps branch of the radial nerve. CC7 to C7 nerve transfer is a reconstructive option in the overall management plan for TBPP. It was safe and effective in restoring shoulder adduction and elbow extension in this patient series. However, recoveries of wrist and finger extensions are poor.</jats:p></jats:sec>

Contralateral C7 Nerve Transfer for Stroke Recovery: New Frontier for Peripheral Nerve Surgery

“…The C7 root fibers are transected at the level of the divisions with meticulous attention to avoid injury to the nearby lateral and posterior cords. On the recipient side, the C7 nerve root contributes to the innervation of several muscles including the latissimus dorsi and pectoralis major (shoulder), triceps (forearm), extensor carpi radialis (wrist) and extensor digitorum (hand) [ 17 ].…”

“…In the most recent stroke trial, the tunnel was developed using the prespinal route (between the esophagus and the vertebral body, medial to the longus colli muscle), which allows for the shortest distance for transfer [ 16 ]. Alternatively, several routes have been described to tunnel the donor C7 root including the retropharyngeal space, posterior to the anterior scalene, subcutaneously or through a retrosternocleidomastoid approach [ 17 , 22 , 23 ]. The closer the tunnel is to the vertebral body, the shorter the required graft segment is and the faster the neurotization and regeneration will occur.…”

“…In the event of an alternative route being chosen and to allow for a tension free suture, sural nerve grafts may be used. Around 3–4 strands of sural nerve graft are commonly used to cover the distance needed to coapt the donor to recipient nerve roots [ 16 , 17 ]. The donor-sural nerve coaptation is completed under an operating microscope and using 9-0 nylon suture to approximate the cut ends of the grafts and the donor divisions, ideally using two grafts per division.…”

Huashan perioperative nursing program for stroke patients undergoing contralateral seventh cervical nerve transfer

“…The injuries include hematoma and injuries of surrounding nerves (e.g., the superior laryngeal nerve, the recurrent laryngeal nerve and the phrenic nerve), which may lead to hoarseness and dyspnea. Additionally, paresthesia is usually reported after nerve transfer (Wang et al, 2018 ), and the management of paresthesia, especially in the presence of severe pain, is also a topic of concern. Targeted care for the above adverse effects is essential for recovery.…”

Huashan Perioperative Nursing Program for Stroke Patients Undergoing Contralateral Seventh Cervical Nerve Transfer

“…The injuries include hematoma and injuries of surrounding nerves (e.g., the superior laryngeal nerve, the recurrent laryngeal nerve and the phrenic nerve), which may lead to hoarseness and dyspnea. Additionally, paraesthesia is usually reported after nerve transfer [7], and the management of paraesthesia, especially in the presence of severe pain, is also a topic of concern. Targeted care for the above side effects is essential for recovery.…”