The radio-radial nerve transfer for elbow extension restoration in C5 to C7 nerve root injury

Brain changes after peripheral nerve repair: limitations of neuroplasticity

Neuroplasticity is the capacity of the central nervous system to adapt to external or internal stimuli. It is being increasingly recognized as an important factor which contributes to the successful outcome of nerve transfers. Other much more well-known factors are the number of axons that cross the coaptation site, the interval between trauma and repair, and age. Neuroplasticity is mediated by synaptic and neurotransmitter changes which underlie activation of previously existing but low-active connections in the brain. Dendritic sprouting and axonal elongation might also take place, but is likely less prominent. We review different factors that play a role in neuroplasticity and functional regeneration after specific nerve transfers. These factors include, amongst others, the distance between cortical areas of the donor and receptor neurons; the presence versus absence of pre-existing low-active inter-neuronal connections; gross versus fine movement restoration; rehabilitation; brain trauma and also very important: the age. The potential for plastic adaptation should be taken into consideration if the surgical strategy and post-operative rehabilitation are planned, as its influence on results cannot be denied.

Reanimation of triceps muscle using ulnar nerve fascicle transfer to the nerve to long head of the triceps muscle

BACKGROUND

Triceps muscle serves an important role in extension of the elbow. Its action is required for reaching out objects without using the trunk. Elbow extension is an important function for natural stabilization of the elbow. The aim of this study was to evaluate restoration of elbow extension in adults suffering triceps muscle palsy with various causes, by using transfer of a fascicle of ulnar nerve to the long head of triceps branch of the radial nerve.

MATERIALS AND METHODS

In the present case series, 7 patients with partial brachial plexus injury or posterior cord injury, where triceps muscle was involved, were subjected to motor fascicle of ulnar nerve transfer to the nerve to long head of triceps for restoration of elbow extension. Follow-ups, including EMG-NCV (electromyography-nerve conduction velocity) 6 and 12 months after surgery and elbow extension muscle strength using MRC grading, were carried out.

RESULTS

Six patients (85.71%) achieved a functional muscle strength of M4 for their elbow extension. In all of the patients, re-innervation was discovered using EMG-NCV.

CONCLUSION

This surgical technique (ulnar nerve fascicle transfer to long head of the triceps) for improving elbow extension is promising in patients with brachial plexus injury.

Current concepts in plasticity and nerve transfers: relationship between surgical techniques and outcomes

OBJECTIVE Neuroplasticity is analyzed in this article as the capacity of the CNS to adapt to external and internal stimuli. It is being increasingly recognized as an important factor for the successful outcome of nerve transfers. Better-known factors are the number of axons that cross the coaptation site, the time interval between trauma and repair, and age. Neuroplasticity is mediated initially by synaptic and neurotransmitter changes. Over time, the activation of previously existing but lowly active connections in the brain cortex contributes further. Dendritic sprouting and axonal elongation might also take place but are less likely to be prominent. METHODS The authors reviewed different factors that play roles in neuroplasticity and functional regeneration after specific nerve transfers. RESULTS The authors found that these different factors include, among others, the distance between cortical areas of the donor and receptor neurons, the presence versus absence of preexisting lowly active interneuronal connections, gross versus fine movement restoration, rehabilitation, brain trauma, and age. CONCLUSIONS The potential for plasticity should be taken into consideration by surgeons when planning surgical strategy and postoperative rehabilitation, because its influence on results cannot be denied.

Outcomes of Transferring a Healthy Motor Fascicle From the Radial Nerve to a Branch for the Triceps to Recover Elbow Extension in Partial Brachial Plexus Palsy

BACKGROUND: Triceps reinnervation is an important objective to pursue when repairing the brachial plexus for cases with upper roots injuries, and a number of different techniques have been developed in order to restore elbow extension in such cases.

OBJECTIVE: To demonstrate the surgical outcomes associated with the technique of transferring a single healthy motor fascicle from the radial nerve of the affected arm to a branch innervating 1 of the 3 heads of the triceps.

METHODS: A retrospective study of 13 adult patients sustaining an upper trunk syndrome associated with total elbow extension palsy who underwent the proposed technique as part of the surgical planning for reconstruction of the brachial plexus.

RESULTS: Outcomes scored as M4 for elbow extension were noted in 9 cases (70%), M3 in 3 (23%), and M1 in 1 subject (7%). No patient considered the postoperative strength for carpal or finger extension as impaired. There were no differences in outcomes by using a fascicle activating carpal or finger extension as donor, as well as regarding the use of the branch to the medial or lateral head of the triceps as the recipient.

CONCLUSION: The technique of transferring a healthy motor fascicle from the radial nerve of the affected side to one of its nonfunctional motor branches to the triceps is an effective and safe procedure for recovering elbow extension function in patients sustaining partial injuries of the brachial plexus.

Motor Nerve Transfers

Brachial plexus and peripheral nerve injuries are exceedingly common. Traditional nerve grafting reconstruction strategies and techniques have not changed significantly over the last 3 decades. Increased experience and wider adoption of nerve transfers as part of the reconstructive strategy have resulted in a marked improvement in clinical outcomes. We review the options, outcomes, and indications for nerve transfers to treat brachial plexus and upper- and lower-extremity peripheral nerve injuries, and we explore the increasing use of nerve transfers for facial nerve and spinal cord injuries. Each section provides an overview of donor and recipient options for nerve transfer and of the relevant anatomy specific to the desired function.

Results of surgical techniques for re-innervation of the triceps as additional procedures for patients with upper root injuries

Patients with injuries restricted to the upper and middle trunks of the brachial plexus may obtain recovery of elbow extension via the lower trunk, which makes it difficult to assess the real effect of interventions to restore the triceps function in such cases. This study aimed to determine the impact of surgical strategies for re-innervation of the triceps in individuals with partial injuries of the brachial plexus. Patients were divided into two groups. Group 1 consisted of 21 participants in whom the surgery included one technique for re-innervation of elbow extension. In this group, six different extra- or intra-plexal donors were targeted to one of the motor branches of the triceps muscle. Group 2 was composed of 24 controls in which the reconstruction did not include any intervention for recovering triceps function. The individuals who underwent intervention for re-innervation of the triceps obtained significantly better outcomes for elbow extension than the controls.

Transfer of median and ulnar nerve fascicles for lesions of the posterior cord in infraclavicular brachial plexus injury: report of 2 cases

In infraclavicular lesions of brachial plexus, severe lesions of the posterior cord often occur when medial and lateral cord function is preserved to a greater or lesser extent. In these cases, shoulder function may be preserved by activity of the muscles innervated by the suprascapular nerve, but complete paralysis exists in the deltoid, triceps, and brachioradialis, and all wrist and finger extensors. Classical reconstruction procedures consist of nerve grafts, but their results in adults are disappointing. We report an approach transferring: (1) an ulnar nerve fascicle to the motor branch of the long portion of the triceps brachii muscle, (2) a median nerve branch from the pronator teres to the motor branch of the extensor carpi radialis longus, and (3) a median nerve branch from the flexor carpi radialis to the posterior interosseous nerve. We describe the procedure and report 2 clinical cases showing the effectiveness of this technique for restoring extension of the elbow, wrist, and fingers in the common infraclavicular lesions of the brachial plexus affecting the posterior cord.