Branches of the lower trunk neurotized by pre-vertebral route contralateral C7 nerve transfer as donor nerves: a preliminary study

Abstract

Objective To explore the feasibility and effectiveness of using branches of the lower trunk on the affected side as donor nerves,i.e.medial brachial cutaneous nerve,medial antebrachial cutaneous nerve and posterior division of the lower trunk,after contralateral C7 nerve root transfer to the lower trunk via pre-vertebral route.Methods When the phrenic nerve and spinal accessory nerve were injured along with the brachial plexus,contralateral C7 nerve root was transferred to repair the lower trunk via pre-vertebral toute.Medial antebrachial cutaneous nerve of the affected side was again transferred to repair the musculocutaneous nerve,medial brachial cutaneous nerve transferred to repair the suprascapular nerve,posterior division of the lower trunk transferred to repair lateral head of the median nerve.A total of 14 cases of complete brachial plexus root avulsions were treated.Results Postoperatively 12 cases were follow-up for 24 to 65 months (mean,35 months).Average shoulder abduction reached 39°.Results in 67％ of the cases were considered effective (musele strength reached M2),and 58 ％ excellent (muscle strength reached M3).The average angle of elbow flexion was 77°,75％ rated effective and 58％ rated excellent.Finger and thumb flexion was restored to some extent.Finger flexor strength was ≥ M2 in 7 cases with an effective rate of 58 ％ and ≥ M3 in 5 cases with an excellent rate of 42％.Conclusion After being neurotized by the contralateral C7 nerve root via pre-vertebral route,branches of the lower trunk can be used as donor nerves to neurotize the musculocutaneous nerve,supraseapular nerve and lateral head of the median nerve. Key words: Brachial plexus; Nerve transfer; Microsurgery; Hand