Median to radial nerve transfer for treatment of radial nerve palsy. Case report

The comparative efficacy of nerve transfer versus tendon transfer in the management of radial palsy: A systematic review and meta-analysis

Background

There is no clear census as to which operative technique provides better recovery for radial nerve injuries. Therefore, in this systematic review, we examined the functional recovery, patient-reported outcomes, and complications of tendon transfer (TT) and nerve transfer (NT).

Methods

Five electronic databases were searched for studies (>10 cases per study) comparing NT and TT regardless of the study design (observational or experimental). Manual search was also conducted. The quality was assessed by the NIH tool. Outcomes included functional recovery, patient-reported outcomes (DASH score, satisfaction, and inability to return to work), and complications. The prevalence was pooled across studies using STATA software, and then, a subgroup analysis based on the intervention type.

Results

Twenty-one studies (542 patients) were analyzed. Excellent recovery, assessed by the Bincaz scale, was higher in the TT group (29 % vs. 11 %) as well as failure to extend the fingers (49 % vs. 9 %). No significant difference was noted between both groups regarding DASH score (mean difference = -2.76; 95 % CI: -12.66: 6.93). Satisfaction was great in the TT group (89 %) with a limited proportion of patients unable to return to work (7 %). Complications were slightly higher in the TT group (8 % vs. 7 %) while 18 % of patients undergoing TT requiring revision surgery. Radial deviation was encountered in 18 % of patients in the TT group and 0 % in the NT group. The quality was good, fair, and poor in 2, 13, and 6, respectively.

Conclusions

In radial nerve injuries, although tendon transfer may seem to provide better functional motor recovery than nerve transfer, it is associated with a higher rate of failure to extend the finger. Given the large confidence interval, the accuracy of this finding is questioned. However, a great proportion of those patients require revision surgery afterward. Additionally, tendon transfer is associated with a greater complication rate than nerve transfer, particularly radial deviation.

Median to Radial Nerve Transfer: An 8-Year Experience From a Lower-Middle Income Country

INTRODUCTION

With an incidence of 2-16%, radial nerve palsy is one of the common forms of nerve injuries globally. Radial nerve palsy causes debilitating effects including loss of elbow extension, wrist drop and loss of finger extension. Reparative surgical pathways range from primary repair and neurolysis, to nerve grafting, nerve transfers, and tendon transfers. Due to ease of performance and acceptability and reproducibility of outcomes, tendon transfers are considered the gold standard of radial nerve palsy repair. However, independent finger function cannot be achieved and as such may not give truly desirable results. In lower-middle income countries, the question of nerve transfer versus tendon transfer for patients who are keen to get back to work is key. While tendon transfer recovery is faster, the functional loss is often considered devastating for fine hand function due to loss of grip secondary to lack of wrist and finger extension. In this study, we present our experience of performing median nerve transfers for radial nerve palsy in Pakistan.

METHODS

We performed a retrospective case-series of patients undergoing median to radial nerve transfer for radial nerve palsy over a period of 6 y, from 2012 to 2019. Patients with radial nerve palsy were diagnosed via electromyography and nerve conduction studies. The procedure involved coapting the branches of the flexor carpi radialis and flexor digitorum superficialis (long and ring finger) nerves to the posterior interosseous nerve and extensor carpi radialis brevis, respectively. Patients were assessed using the Medical Research Council scale for muscle strength of wrist, finger and thumb extension separately at 1 y time. Our results were then compared to results from similar nerve transfer studies.

RESULTS

We operated on 10 right-hand dominant patients, eight males and two females with a median age of 33 y (6-63 y). four sustained injury to the right hand and six to the left. Causes of the injuries included road traffic accident (n = 3), firearm injury (n = 4), shrapnel (n = 1), iatrogenic injury (injection in deltoid region (n = 1) and fall (n = 1). Types of fracture included mid humerus fracture, fracture of the surgical neck of the humerus, and supracondylar fracture of the humerus. Median time to surgery since injury was 4 mo (1-8 mo). Independent wrist extension was M4+ in all patients and independent finger extension was M4+ in seven and M4-in two patients. However, a patient who presented late at 8 mo had poorer finger outcomes with extension at M2-. All patients had independent movement of fingers.

CONCLUSIONS

Nerve transfer is a reliable method of post traumatic nerve repair and reinnervation, particularly in lower-middle income countries, even in cases where the nerve damage is severe and extensive and up to 6 mo may have elapsed between injury and presentation. Timely median to radial nerve transfer is a highly recommended option for radial nerve palsy, with regular follow-ups and physical therapy added to ensure positive outcomes.

Expectant Management, Tendon Transfer, or Nerve Transfer Surgery for Radial Nerve Injury: A Qualitative Study Exploring Patient Expectations, Goals, and Treatment Experiences

BACKGROUND

After a radial nerve injury, patients must weigh a complicated set of advantages and disadvantages to observation or surgery. We conducted semistructured interviews to characterize the decision-making process that these patients undertake.

METHODS

We recruited participants who were treated with expectant management (nonoperatively), received only a tendon transfer, or received a nerve transfer. Participants completed a semistructured interview that was transcribed and coded to identify recurring themes, to describe the influence of qualitative findings on treatment decision-making.

RESULTS

We interviewed 15 participants (5 expectant management, 5 tendon transfer only, and 5 nerve transfer). Participants' primary concerns were returning to work, hand appearance, regaining motion, resuming activities of daily living, and enjoying hobbies. Delayed diagnosis and/or insurance coverage led 3 participants to change treatment from nerve transfer to isolated tendon transfer. Interactions with providers early in diagnosis and treatment had strong effects on how members of the care team were perceived. The hand therapist was the primary person who shaped expectations, provided encouragement, and prompted referral to the treating surgeon. Participants valued debate among the care team members regarding treatment, provided that medical terminology was explained.

CONCLUSIONS

This study highlights the importance of initial, collaborative care in setting expectations for patients with radial nerve injuries. Many participants named returning to work and hand appearance as primary concerns. Hand therapists were the primary source of support and information during recovery.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Distal Nerve Transfer to Restore Wrist and Finger Extension - A Systematic Review

Background: There are numerous options available for restoration of wrist and finger extension following radial nerve palsy. The aim of this study is to conduct a systematic review of the effectiveness of nerve transfer for radial nerve palsy. Methods: Electronic literature research of PubMed, Cochrane, Scopus and Lilacs database was conducted in June 2021 using the terms 'Distal nerve transfer' AND 'Radial nerve injury' 'Radial nerve palsy' OR 'Radial nerve paresis' OR 'Median nerve transfer' OR 'wrist extensor' OR 'finger extension' OR 'thumb extension' OR 'wrist motion'. The data extracted included the study details, demographic data, procedure performed and final functional outcome according to the muscle research council scale. Results: A total of 92.59% and 56.52% had satisfactory outcome following distal nerve transfer of median nerve to restore wrist and finger extension respectively. No significant correlation was found between time to injury duration and satisfactory outcomes. Conclusions: Outcomes of nerve transfers are comparable to tendon transfers. Multi-centric studies are needed to compare the results amongst various surgical procedures described. Level of Evidence: Level III (Therapeutic).

Radial Nerve Palsy: Nerve Transfer Versus Tendon Transfer to Restore Function

BACKGROUND

Radial nerve injuries cause profound disability, and a variety of reconstruction options exist. This study aimed to compare outcomes of tendon transfers versus nerve transfers for the management of isolated radial nerve injuries.

METHODS

A retrospective chart review of 30 patients with isolated radial nerve injuries treated with tendon transfers and 16 patients managed with nerve transfers was performed. Fifteen of the 16 patients treated with nerve transfer had concomitant pronator teres to extensor carpi radialis brevis tendon transfer for wrist extension. Preoperative and postoperative strength data, Disabilities of the Arm, Shoulder, and Hand (DASH) scores, and quality-of-life (QOL) scores were compared before and after surgery and compared between groups.

RESULTS

For the nerve transfer group, patients were significantly younger, time from injury to surgery was significantly shorter, and follow-up time was significantly longer. Both groups demonstrated significant improvements in grip and pinch strength after surgery. Postoperative grip strength was significantly higher in the nerve transfer group. Postoperative pinch strength did not differ between groups. Similarly, both groups showed an improvement in DASH and QOL scores after surgery with no significant differences between the 2 groups.

CONCLUSIONS

The nerve transfer group demonstrated greater grip strength, but both groups had improved pain, function, and satisfaction postoperatively. Patients who present early and can tolerate longer time to functional recovery would be optimal candidates for nerve transfers. Both tendon transfers and nerve transfers are good options for patients with radial nerve palsy.

A novel dual nerve transfer for restoration of shoulder function and sensory recovery of the hand, in patients with C567 traumatic root avulsion of the brachial plexus

OBJECTIVE

The objective of our study is to determine the anatomical viability in cadavers of a novel doble nerve transfer technique for simultaneous reanimation of shoulder abduction and sensory recovery of the hand, in patients with brachial plexus injuries sustaining a C5-C6-C7 roots avulsion. These new transfers should be complemented in the clinical setting with other classic nerve transfers, i.e.: (1) a spinal accessory to suprascapular for shoulder abduction and stability, (2) ulnar nerve fascicles to the biceps branches of the musculocutaneous for elbow flexion, and (3) intercostal to triceps branches for elbow extension.

METHODS

The proposed surgical technique includes (1) transferring motor fascicles of the median nerve (MNF), as donors to the axillary nerve (AN), and (2) the whole medial antebrachial cutaneous nerve (MACN) to the lateral contribution (sensory) of the median nerve (LCMN), both without the use of interposed nerve grafts. These techniques were performed in eight cadaveric upper extremities. Analyzed variables were: donor and receptor nerves diameter, length and distance of donor and receptors nerves, and axonal count.

RESULTS

The mean distance between the MNF and its point of coaptation to the AN was 19 mm. The average length of each one of the MNF, after distal dissection, was 46.5 mm. The average diameter of each fascicle of the median nerve at its coaptation point with the axillary nerve was 0.8 mm, while the average diameter of the latter was 3.9 mm. The average distance between the MACN and its point of coaptation to the LCMN, was 16.5 mm. The average diameter of the MACN and the LCMN at their point of coaptation, were 2.7 mm and 3.5 mm, respectively.

CONCLUSION

These nerve transfers are anatomically viable and could be a complement for other currently used techniques that can be employed in severely injured C567 brachial plexus patients.

Nerve Grafting for Chronic PIN Palsy Due to Radiocapitellar Joint Entrapment 2 Years Following Closed Reduction of a Pediatric Monteggia Fracture-Dislocation: A Case Report With 1-Year Follow-up

This article describes the first case of successful nerve grafting for posterior interosseous nerve (PIN) palsy secondary to radiocapitellar joint entrapment 2 years following closed reduction (CR) of a pediatric Monteggia fracture-dislocation (MFD). Patient notes were examined. The literature was reviewed to determine whether similar cases or techniques had been reported. A 5-year-old girl presented with a PIN palsy 2 years following CR of an MFD, demonstrating Medical Research Council (MRC) grade 4 wrist and MRC grade 2 finger and thumb extension. Nerve exploration at 27 months revealed a PIN crushed in the radiocapitellar joint with a proximal neuroma-in-continuity and no response to electrical stimulation. Neurolysis and lateral antebrachial cutaneous nerve cable grafting were performed. The decision to pursue nerve grafting was based on the intraoperative appearance of an atrophic PIN with no response to stimulation, but with minimal muscle atrophy, short distance to target muscles, and pediatric patient with extended reinnervation timeline. Full recovery (MRC grade 5 wrist extension and MRC grade 4+ finger and thumb extension) was achieved at 1-year follow-up. We present the first case of successful nerve grafting for PIN palsy secondary to radiocapitellar joint entrapment 2 years following CR of a type III MFD. Even with significant treatment delay, nerve reconstruction should be considered in the pediatric population.

Radial nerve palsy following humeral shaft fracture: a theoretical PNF rehabilitation approach for tendon and nerve transfers

Background:Humerus fracture-induced radial nerve injury can create severe and permanent disabilities. Purpose:Surgical management often relies on either tendon or nerve transfer. Regardless of which procedure is selected, physical therapists are challenged to restore functional outcomes without jeopardizing repair healing. Through synergistic, multi planar upper extremity movement patterns, neuromuscular irradiation, or overflow, and neuroplasticity, proprioceptive neuromuscular facilitation (PNF) may improve strength, range of motion and tone. Methods:After reviewing the literature, a five phase PNF-based treatment approach is proposed with timing differences based on the selected procedure. Findings:Phase I (2 or 4 weeks pre-surgery for tendon or nerve transfer, respectively) consists of comprehensive patient education; Phase II (4-6 or 1-2 weeks post-surgery for tendon or nerve transfer, respectively) explores variable duration peripheral and central nervous system motor learning during isometric activation to enhance central neuroplasticity; Phase III (7-12 or 3-20 weeks post-surgery for tendon or nerve transfer, respectively) incorporates low-intensity motor control including contralateral isotonic upper extremity loading to maximize overflow and neuroplastic effects; Phase IV (13-26 or 21-52 weeks post-surgery for tendon or nerve transfer, respectively) adds high-intensity strength and motor control using ipsilateral isotonic upper extremity loading to maximize overflow and neuroplastic effects. Phase V (27-52 or 53-78 weeks post-surgery for tendon or nerve transfer, respectively) progresses to more activity of daily living, vocational, or sport-specific training with higher intensity strength and motor control tasks. Conclusions:Through manually guided synergistic, multi planar movement, overflow, and neuroplasticity, a PNF treatment approach may optimize neuromuscular recovery. Validation strategies to confirm clinical treatment efficacy are discussed.

Prevention and Treatment of Nerve Injuries in Shoulder Arthroplasty

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Nerve injuries during shoulder arthroplasty have traditionally been considered rare events, but recent electrodiagnostic studies have shown that intraoperative nerve trauma is relatively common.

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The brachial plexus and axillary and suprascapular nerves are the most commonly injured neurologic structures, with the radial and musculocutaneous nerves being less common sites of injury.

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Specific measures taken during the surgical approach, component implantation, and revision surgery may help to prevent direct nerve injury. Intraoperative positioning maneuvers and arm lengthening warrant consideration to minimize indirect injuries.

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Suspected nerve injuries should be investigated with electromyography preferably at 6 weeks and no later than 3 months postoperatively, allowing for primary reconstruction within 3 to 6 months of injury when indicated. Primary reconstructive options include neurolysis, direct nerve repair, nerve grafting, and nerve transfers.

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Secondary reconstruction is preferred for injuries presenting >12 months after surgery. Secondary reconstructive options with favorable outcomes include tendon transfers and free functioning muscle transfers.

Nerve transfers in the upper extremity: A review

Injury of the brachial plexus and peripheral nerve often result in significant upper extremity dysfunction and disability. Nerve transfers are replacing other techniques as the gold standard for brachial plexus and other proximal peripheral nerve injuries. These transfers require an intimate knowledge of nerve topography, a technically demanding Intraneural dissection and require extensive physical therapy for retraining. In this review, we present a summary of the most widely accepted nerve transfers in the upper extremity described in the current literature.

Trends in Nerve Transfer Procedures Among Board-Eligible Orthopedic Hand Surgeons

Purpose

Enthusiasm for peripheral nerve transfers increased over the past several years, but further studies are still needed to establish the role of these procedures in peripheral nerve reconstruction. The primary goal of this study was to describe the frequency of nerve transfer surgery among newly trained orthopedic surgeons.

Methods

We queried the American Board of Orthopaedic Surgery Part II case log database for all nerve reconstruction Current Procedural Terminology codes for examination years 2004 to 2018 for surgeries performed between 2003 and 2017. Information collected for each patient included examination year, year of surgery, surgeon fellowship training subspecialty, geographic region (as defined by the American Board of Orthopaedic Surgery Part II case log database), patient age, and patient sex.

Results

A total of 3,359 nerve reconstruction cases were logged by 1,542 individual candidates from examination years 2004 to 2018. Of the nerve reconstruction codes, 2.1% were nerve transfer codes. There was a statistically significant increase in the proportion of nerve transfer codes over the study period, from 0% of nerve reconstruction codes in examination years 2004 to 2006 to 4.1% of nerve reconstruction codes in examination years 2016 to 2018 (Z = –6.82; P < .001).

Conclusions

There has been an increase in the number of nerve transfer procedures relative to all nerve reconstruction codes for peripheral nerve conditions.

Clinical relevance

There is a modest but significant increase in nerve transfer procedures over time among newly trained orthopedic surgeons, which suggests the need for long-term outcomes studies for nerve transfers procedures performed in the setting of peripheral nerve conditions.

Nerve Transfer from the Long Head Triceps Nerve to Posterior Interosseous Nerve for Restoration of Wrist, Finger, and Thumb

In brachial plexus injuries where the radial nerve is damaged, there is loss of wrist, finger, and thumb extension. Surgical options for treating brachial plexus injuries are case dependent. To restore finger and wrist extension, the median nerve is primarily utilized for nerve transfer. We describe a new technique in a young man who suffered a gunshot wound in the left axilla, injuring the radial, median, and ulnar nerves. To restore wrist, finger, and thumb extension, we designed and performed a new technique consisting of nerve transfer, an interposition sural nerve graft from the motor branch of the long triceps portion to the posterior interosseous nerve. Positive outcomes were seen after 18 months with postoperative recovery of the functionality of finger and wrist extension.

Median to radial nerve transfer after traumatic radial nerve avulsion in a pediatric patient

This case report describes an isolated radial nerve avulsion in a pediatric patient, treated by combination sensory and motor median to radial nerve transfers. After traumatic avulsion of the proximal radial nerve, a 12-year-old male patient underwent end-to-end transfer of median nerve branches to flexor carpi radialis and flexor digitorum superficialis to the posterior interosseous nerve and extensor carpi radialis nerve, respectively. He underwent end-to-side sensory transfer of the superficial radial sensory to the median sensory nerve. Pronator teres to extensor carpi radialis brevis tendon transfer was simultaneously performed to power short-term wrist extension. Within months after surgery, the patient had regained 9-10/10 sensation in the hand and forearm. In the following months and years, he regained dexterity, independent fine-finger and thumb motions, and 4-5/5 strength in all extensors except the abductor pollicis longus muscle. He grew 25 cm without extremity deformity or need for secondary orthopedic procedures. In appropriate adult and pediatric patients with proximal radial nerve injuries, nerve transfers have advantages over tendon transfers, including restored independent fine finger motions, regained sensation, and reinnervation of multiple muscle groups with minimal donor sacrifice.

Systematic Review of Tendon Transfer Versus Nerve Transfer for the Restoration of Wrist Extension in Isolated Traumatic Radial Nerve Palsy

Purpose:

To compare the outcomes of tendon transfer and nerve transfer for radial nerve palsy.

Methods:

We performed a systematic review of the literature in EMBASE, PubMed, and Cochrane Database to include studies that address persistent traumatic radial nerve palsy treated with tendon transfer or nerve transfer surgery.

Results:

We identified 2,044 citations; 1,512 texts were excluded because of content, and 96 texts were screened for eligibility. Texts were excluded if they did not report the motor score (M0 to M5 as determined by the British Medical Research Council) or measurements of range of motion of the wrist. Sixteen texts were eligible for qualitative synthesis. Outcomes of these studies show heterogeneity with regard to the technique and functional restoration.

Conclusions:

On the basis of the results of this systematic review, there does not seem to be a clearly superior technique; rather, there are advantages and disadvantages to each. Patient selection and surgeon experience are important when considering surgical interventions in this challenging clinical scenario. Nerve transfer surgery is an emerging technique that may offer patients meaningful functional gains with reduced donor site morbidity.

Level of Evidence:

Level III

Peripheral nerve intersectional repair by bi-directional induction and systematic remodelling: biodegradable conduit tubulization from basic research to clinical application

In terms of the clinical effect of peripheral nerve injury repair, the biological degradable conduit 2 mm small gap tubulization is far better than the traditional epineurial or perineurium neurorrhaphy. The assumption of the bi-directional induction between the central system and the terminal effector during peripheral nerve regeneration is purposed and proved in clinical by our group. The surgical approach of transferring a portion of or the whole contralateral C7 nerve to repair a part of or the whole ipsilateral brachial plexus injury is clinically promoted, in which the most important idea and practice is to use the cone conduit designed by the group to repair thick nerves with fine nerves. Some of the patients suffering from cerebral palsy or cerebral haemorrhage and those who got cerebral infarction yet have not reached recovery after 3-6 months could regain some functions of the ipsilateral upper limb and improve the life quality by transfer of a portion of or the whole contralateral C7 nerve and connection by cone conduit.

Radial nerve palsy

As a result of its proximity to the humeral shaft, as well as its long and tortuous course, the radial nerve is the most frequently injured major nerve in the upper limb, with its close proximity to the bone making it vulnerable when fractures occur.Injury is most frequently sustained during humeral fracture and gunshot injuries, but iatrogenic injuries are not unusual following surgical treatment of various other pathologies.Treatment is usually non-operative, but surgery is sometimes necessary, using a variety of often imaginative procedures. Because radial nerve injuries are the least debilitating of the upper limb nerve injuries, results are usually satisfactory.Conservative treatment certainly has a role, and one of the most important aspects of this treatment is to maintain a full passive range of motion in all the affected joints.Surgical treatment is indicated in cases when nerve transection is obvious, as in open injuries or when there is no clinical improvement after a period of conservative treatment. Different techniques are used including direct suture or nerve grafting, vascularised nerve grafts, direct nerve transfer, tendon transfer, functional muscle transfer or the promising, newer treatment of biological therapy. Cite this article: Bumbasirevic M, Palibrk T, Lesic A, Atkinson HDE. Radial nerve palsy. EFORT Open Rev 2016;1:286-294. DOI: 10.1302/2058-5241.1.000028.

Donor Activation Focused Rehabilitation Approach: Maximizing Outcomes After Nerve Transfers

As nerve transfers become the mainstay in treatment of brachial plexus and isolated nerve injuries, the preoperative and postoperative therapy performed to restore motor function requires continued dedication and appreciation. Through the understanding of the general principles of muscle activation and patient education, the therapist has a unique impact on the return of function in patients with nerve injuries. As surgeons continue to develop novel nerve transfers, the perioperative training, education, and implementation of the donor activation focused rehabilitation approach model is critical to ensure successful outcomes.

Nerve Transfers for the Restoration of Wrist, Finger, and Thumb Extension After High Radial Nerve Injury

High radial nerve injury is a common pattern of peripheral nerve injury most often associated with orthopedic trauma. Nerve transfers to the wrist and finger extensors, often from the median nerve, offer several advantages when compared to nerve repair or grafting and tendon transfer. In this article, we discuss the forearm anatomy pertinent to performing these nerve transfers and review the literature surrounding nerve transfers for wrist, finger, and thumb extension. A suggested algorithm for management of acute traumatic high radial nerve palsy is offered, and our preferred surgical technique for treatment of high radial nerve palsy is provided.

Useful Functional Outcome Can Be Achieved After Motor Nerve Transfers in Management of the Paralytic Hand. An Observational Study

BACKGROUND

Nerve transfers have demonstrated encouraging outcomes in peripheral nerve reconstructions compared with the conventional direct repair or grafting.

QUESTIONS/PURPOSES

We aimed to identify whether the patient's demographics, delay to surgery, degree of loss of grip and pinch strengths, mechanism of injury, and compliance to hand therapy have an impact on the functional outcome of motor nerve transfers in patients with paralytic hand.

METHODS

Fifty-five patients with a mean age of 31.05 (18-48) years with complete isolated high injuries of radial, ulnar, and median nerves, who underwent motor nerve transfers, were reviewed. The outcome was assessed using the Medical Research Council (MRC) scale and measurement of grip and pinch strengths of the hand at minimum 1-year follow-up (mean of 14.4 (12-18) months). Patient's age and gender, delay to surgery, body mass index (BMI), degree of loss of grip and pinch strengths, educational level, occupation, mechanism of injury, and compliance to hand therapy were analyzed to determine their impact on the extent of recovery of hand function.

RESULTS

Forty of fifty five (72.73%) patients regained useful functional recovery (M3-M4) with satisfactory grip hand functions. Worse motor recovery was observed in older ages, delayed surgical intervention, higher BMI, and greater postoperative loss of grip and pinch strengths in comparison to the healthy opposite hand. Better outcomes are significantly associated with higher educational level and postoperative compliance to hand therapy. Contrarily, there was no significant association between gender, occupation, mechanism of injury, and achievement of useful functional recovery.

CONCLUSIONS

Successful nerve transfers are expected with experienced skilled surgeons. However, outstanding outcomes are not the standard, with about one fourth failing to achieve M3 grade. The educational level, hand dominance, compliance to hand therapy, loss of grip and pinch strengths, age, injury-surgery interval, and BMI are possible predictors of patients' outcome.

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.

Nerve gaps

SUMMARY

Peripheral nerve injury is a significant problem affecting greater that 1 million people around the world each year and poses major challenges to the plastic and reconstructive surgeon. When primary nerve repair is not possible, several options for management of the nerve gap include a nerve autograft, nerve conduit, and acellular nerve allograft. For extensive and proximal nerve injuries, cellular nerve allografts and nerve transfers may be considered. This article reviews the indications and outcomes for each option, as in many cases more than one option may be acceptable.

Diagnostic biopsy of the pronator teres and a motor branch of the median nerve: indications and technique

PURPOSE

Biopsy of muscle tissue and motor nerve is helpful in the neurological evaluation of patients who present with upper limb and/or diffuse motor weakness. The procedure is indicated to supplement clinical, serological, and imaging diagnostic work-up of myopathic and neuropathic disorders. We describe a surgical technique and clinical series of biopsy of the pronator teres muscle and a motor branch of the median nerve.

METHODS

We performed a retrospective review of 20 patients who underwent biopsy of the pronator teres and a motor branch of the median nerve as part of a clinical, serological, and radiographic evaluation for weakness of the upper extremity. All of the biopsies were performed by a single surgeon. The surgical technique is described. Follow-up visits with both the surgeon and the neurologist were reviewed to evaluate preoperative and postoperative neurological function to identify any changes in nerve or muscle function and any postoperative complications.

RESULTS

Biopsied tissue was sufficient for pathological diagnosis in all 20 patients. Diagnoses included multifocal motor neuropathy in 14 patients, amyotrophic lateral sclerosis in 3 patients (2 sporadic; 1 familial), inclusion body myositis (1 patient), inflammatory myopathy (1 patient), and chronic inflammatory demyelinating polyneuropathy (1 patient). At a mean follow-up of 11 weeks (range, 5-31 wk), there were 6 minor surgical complications, all of which were superficial hematomas that resolved with use of a compressive wrap.

CONCLUSIONS

Biopsy of the pronator teres and a motor branch of the median nerve was safe and effective. The technique is particularly useful when considering the diagnosis of multifocal motor neuropathy affecting the upper extremity.

Combined proximal nerve graft and distal nerve transfer for a posterior cord brachial plexus injury

The treatment of patients with prolonged denervation from a posterior cord brachial plexus injury is challenging and no management guidelines exist to follow. The authors describe the case of a 26-year-old man who presented to our clinic for treatment 11 months after suffering a high-energy injury to the posterior cord of the brachial plexus. A combined 9-cm proximal cable nerve graft procedure and a pronator branch to the posterior interosseous nerve transfer were performed. Satisfactory deltoid, triceps, wrist, and finger extensor recovery was noted 3 years after surgery. Patients with prolonged denervation from posterior cord injuries can be successfully treated with a combination of a proximal nerve graft and a distal nerve transfer.

Nerve transfers for the upper extremity: new horizons in nerve reconstruction

Nerve transfers are key components of the surgeon's armamentarium in brachial plexus and complex nerve reconstruction. Advantages of nerve transfers are that nerve regeneration distances are shortened, pure motor or sensory nerve fascicles can be selected as donors, and nerve grafts are generally not required. Similar to the principle of tendon transfers, expendable donor nerves are transferred to denervated nerves with the goal of functional recovery. Transfers may be subdivided into intraplexal, extraplexal, and distal types; each has a unique role in the reconstructive process. A thorough diagnostic workup and intraoperative assessment help guide the surgeon in their use. Nerve transfers have made a positive impact on the outcomes of nerve surgery and are essential tools in complex nerve reconstruction.

Clinical outcomes following median to radial nerve transfers

PURPOSE

To evaluate the clinical outcomes in patients with radial nerve palsy who underwent nerve transfers using redundant fascicles of median nerve (innervating the flexor digitorum superficialis and flexor carpi radialis muscles) to the posterior interosseous nerve and the nerve to the extensor carpi radialis brevis.

METHODS

This was a retrospective review of the clinical records of 19 patients with radial nerve injuries who underwent nerve transfer procedures using the median nerve as a donor nerve. All patients were evaluated using the Medical Research Council (MRC) grading system. The mean age of patients was 41 years (range, 17-78 y). All patients received at least 12 months of follow-up (range, 20.3 ± 5.8 mo). Surgery was performed at a mean of 5.7 ± 1.9 months postinjury.

RESULTS

Postoperative functional evaluation was graded according to the following scale: grades MRC 0/5 to MRC 2/5 were considered poor outcomes, whereas an MRC grade of 3/5 was a fair result, 4/5 was a good result, and 4+/5 was an excellent outcome. Postoperatively, all patients except one had good to excellent recovery of wrist extension. A total of 12 patients recovered good to excellent finger and thumb extension, 2 had fair recovery, and 5 had poor recovery.

CONCLUSIONS

The radial nerve is commonly injured, causing severe morbidity in affected patients. The median nerve provides a reliable source of donor nerve fascicles for radial nerve reinnervation. The important nuances of both surgical technique and motor reeducation critical for the success of this transfer have been identified and are discussed.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Median nerve branches to the pronator teres: cadaveric study with potential use in neurotization procedures to the radial nerve at the elbow

Object

Various donor nerves have been used for brachial plexus neurotization procedures. To the authors' knowledge, neurotization of median nerve branches to the pronator teres to the radial nerve at the elbow have not been explored.

Methods

In an attempt to identify an additional nerve donor candidate for neurotization procedures of the upper limb, 20 cadaveric upper limbs underwent dissection of the cubital fossa and identification of branches of the median nerve to the pronator teres. Measurements were made of such branches, and distal transection was then performed to determine the appropriate length so that the structure could be brought to the laterally positioned radial nerve via tunneling deep to the biceps brachii muscle.

Results

All specimens were found to have a median nerve branch to the pronator teres that was long enough to reach the radial nerve in the cubital fossa. Neural connections remained tension free with full pronation and supination. The mean length of these branches to the pronator teres was 3.6 cm. The overall mean diameter of these nerves was 1.5 mm. The mean proximal, midpoint, and distal diameters were 2.0, 1.8, and 1.5 mm, respectively. The mean distance between the origin of these branches to the pronator teres and the medial epicondyle of the humerus was 4.1 cm.

Conclusions

Based on the results of our cadaveric study, the use of the branch of the median nerve to the pronator teres muscle may be considered for neurotization of the radial nerve in the cubital fossa.

Post-Cervical Decompression Parsonage-Turner Syndrome Represents a Subset of C5 Palsy: Six Cases and a Review of the Literature: Case Report

BACKGROUND:

Approximately 5% of cervical decompression cases are complicated by postoperative weakness. Parsonage-Turner syndrome (PTS) or neuralgic amyotrophy is known to be precipitated by surgery and unrelated to technical or structural issues. Our practice has seen a number of cases of PTS after cervical decompression surgery. In this case report, we discuss a series of such patients, highlighting the commonalities with the more frequently diagnosed C5 palsy. We conclude with our management algorithm.

CLINICAL PRESENTATION:

Six patients with post-cervical decompression PTS were referred to our institution during a 32-month period. All patients were examined physically, radiographically, and electromyographically and were followed for up to 2 years or until symptoms resolved. Conservative management was the rule, and surgical intervention, including nerve releases and nerve reconstruction, was undertaken in select circumstances. In the majority of patients (4 of 6 patients), pain management and physical therapy alone were used and achieved eventual resolution of pain and recovery of motor strength. The other 2 patients required adjunctive surgical procedures to maximize their outcomes.

CONCLUSION:

PTS accounts for a subset of patients experiencing postoperative weakness after cervical decompression operations. Although it is at times difficult to arrive at this diagnosis, an understanding of the history of PTS, among other causes of postoperative weakness, allows a structured approach to these patients. An evidence-based approach to management helps provide the best outcome for a given patient.

Functional recovery following an end to side neurorrhaphy of the accessory nerve to the suprascapular nerve: case report

The use of end-to-side neurrorhaphy remains a controversial topic in peripheral nerve surgery. The authors report the long-term functional outcome following a modified end-to-side motor reinnervation using the spinal accessory to innervate the suprascapular nerve following a C5 to C6 avulsion injury. Additionally, functional outcomes of an end-to-end neurotization of the triceps branch to the axillary nerve and double fascicular transfer of the ulnar and medial nerve to the biceps and brachialis are presented. Excellent functional recoveries are found in respect to shoulder abduction and flexion and elbow flexion.

ELECTRONIC SUPPLEMENTARY MATERIAL

The online version of this article (doi:10.1007/s11552-009-9242-3) contains supplementary material, which is available to authorized users.

Median to radial nerve transfer to restore wrist and finger extension: technical nuances

BACKGROUND

Traditional methods for restoring finger and wrist extension following radial nerve palsy include interposition nerve grafting or tendon transfers. We have described the utilization of distal nerve transfers for the restoration of radial nerve function in the forearm.

OBJECTIVE

We review the neuroanatomy of the forearm and outline the steps required for the implementation of this transfer.

METHODS AND RESULTS

We use a step-by-step procedural outline and detailed photographs, line drawings, and video to describe the procedure.

CONCLUSION

This approach is technically feasible and is a reconstructive option for patients with this nerve deficit.

Proximal motor branches from the tibial nerve as direct donors to restore function of the deep fibular nerve for treatment of high sciatic nerve injuries: a cadaveric feasibility study

OBJECTIVE

The results of surgical repair of the fibular division of the sciatic nerve have been considered unsatisfactory, especially if grafts are necessary to reconstruct the nerve. To consider the clinical application of the concept of distal nerve transfer for the treatment of high sciatic nerve injuries, this study aimed to determine detailed anatomic data about the possible donor branches from the tibial nerve that are available for reinnervation of the deep fibular nerve at the level of the popliteal fossa.

METHODS

An anatomic study was performed that included the dissection of the popliteal fossa in 12 lower limbs of 6 formalin-fixed adult cadavers. It focused on the detailed anatomy of the tibial nerve and its branches at the level of the proximal leg as well as the anatomy of the common fibular nerve and its largest divisions at the level of the neck of the fibula, i.e., the deep and superficial fibular nerves.

RESULTS

The branches of the tibial nerve destined to the lateral and medial head of the gastrocnemius had a mean length of 43 mm and 35 mm, respectively. The branch to the posterior soleus muscle had a mean length of 65 mm. Intraneural dissection of the common fibular nerve, isolating its deep and superficial fibular divisions, was possible to a proximal mean distance of 71 mm. A tensionless direct suture to the deep fibular nerve was made possible by using the nerve to the lateral head of the gastrocnemius and the nerve to the posterior soleus muscle in all specimens. Direct suture of the nerve to the medial head of the gastrocnemius was possible in all cases except 1.

CONCLUSION

The nerve to the lateral and medial heads of the gastrocnemius and the nerve to the posterior soleus muscle can be used as donors to restore function of the deep fibular nerve in cases of high sciatic nerve injury. However, proximal intraneural dissection of the deep fibular division of the common fibular nerve must also be performed. We recommend that the nerve to the posterior soleus muscle should be the first choice for a donor in the proposed transfer.

Nerve transfers: indications, techniques, and outcomes

This article provides an update of the current strategies of motor and sensory nerve transfers for peripheral nerve lesions of the upper extremity. Indications, techniques, and outcomes are summarized for both well-established transfers used in the management of proximal and brachial plexus injuries as well as those more recently developed for more distal and isolated nerve injuries in the forearm and hand.

Nerve transfer for wrist extension using nerve to flexor digitorum superficialis in cervical 5, 6, and 7 root avulsions: anatomic study and report of two cases

PURPOSE

To evaluate the feasibility of restoring wrist extension in patients with complete cervical root 5 (C5), 6, and 7 avulsion injuries by transferring the most proximal branch of the median nerve that innervates flexor digitorum superficialis (FDS) muscle (proximal FDS branch) to the branch of the radial nerve that innervates extensor carpi radialis brevis (ECRB) muscle (ECRB branch) in an anatomic study and 2 case reports.

METHODS

The study was performed on 10 fresh cadavers. The nerve branches of the median nerve and the radial nerve were measured for length, diameter, and sites of origin of their nerve branches. The nerve branches of the median nerve, the posterior interosseous nerve, and the ECRB branch of the radial nerve were processed for histomorphometric evaluation. Using image analysis software, we took all histomorphometric measurements of the nerve sections. Based on this anatomical study, the proximal FDS branch was transferred directly to the ECRB branch without nerve graft in 2 patients.

RESULTS

The average distance from the origin of nerve branches to the interepicondylar line was 3.5 and 2.3 cm, respectively, for the proximal FDS and ECRB branches. The average length of the proximal FDS branch and ECRB branch was 2.8 and 3.3 cm, respectively. The average number of myelinated nerve fibers of the proximal FDS branch and ECRB branch was 983 and 2,797, respectively. At 2 years' follow-up, preliminary clinical results demonstrated that wrist extension had gained strength against resistance (grade M4). The arc of motion for wrist extension was 30 degrees in the first patient and 70 degrees in the second one. Useful functional recovery was achieved and classified as good result in both cases.

CONCLUSIONS

The anatomic study and 2 reported results supports our hypothesis that transfer of the proximal FDS branch of median nerve to the ECRB branch of radial nerve could be an alternative method for reconstructiing wrist extension in C5, 6, and 7 avulsion injuries.

Nerve allotransplantation as it pertains to composite tissue transplantation

Nerve allografts provide a temporary scaffold for host nerve regeneration and allow for the repair of significant segmental nerve injuries. From rodent, large animal, and nonhuman primate studies, as well as clinical experience, nerve allografts, with the use of immunosuppression, have the capacity to provide equal regeneration and function to that of an autograft. In contrast to solid organ transplantation and composite tissue transfers, nerve allograft transplantation requires only temporary immunosuppression. Furthermore, nerve allograft rejection is difficult to assess, as the nerves are surgically buried and are without an immediate functional endpoint to monitor. In this article, we review what we know about peripheral nerve allograft transplantation from three decades of experience and apply our current understanding of nerve regeneration to the emerging field of composite tissue transplantation.

Motor nerve transfers to restore extrinsic median nerve function: case report

Active pronation is important for many activities of daily living. Loss of median nerve function including pronation is a rare sequela of humerus fracture. Tendon transfers to restore pronation are reserved for the obstetrical brachial plexus palsy patient. Transfer of expendable motor nerves is a treatment modality that can be used to restore active pronation. Nerve transfers are advantageous in that they do not require prolonged immobilization postoperatively, avoid operating within the zone of injury, reinnervate muscles in their native location prior to degeneration of the motor end plates, and result in minimal donor deficit. We report a case of lost median nerve function after a humerus fracture. Pronation was restored with transfer of the extensor carpi radialis brevis branch of the radial nerve to the pronator teres branch of the median nerve. Anterior interosseous nerve function was restored with transfer of the supinator branch to the anterior interosseous nerve. Clinically evident motor function was seen at 4 months postoperatively and continued to improve for the following 18 months. The patient has 4+/5 pronator teres, 4+/5 flexor pollicis longus, and 4-/5 index finger flexor digitorum profundus function. The transfer of the extensor carpi radialis brevis branch of the radial nerve to the pronator teres and supinator branch of the radial nerve to the anterior interosseous nerve is a novel, previously unreported method to restore extrinsic median nerve function.

Nerve transfers in the forearm and hand

In the forearm, vital and expendable functions have been identified, and tendon transfers use these conventions to maximize function and minimize disability. Using similar concepts, distal nerve transfers offer a reconstruction that often is superior to reconstruction accomplished by traditional grafting. The authors present nerve transfer options for restoring motor and sensory deficits within each nerve distribution on the forearm and hand.