High Median Nerve Injury: Motor and Sensory Nerve Transfers to Restore Function

Timing of surgery in peripheral nerve injury of the upper extremity

Peripheral nerve injuries present a complex clinical challenge, requiring a nuanced approach in surgical management. The consequences of injury vary, with sometimes severe disability, and a risk of lifelong pain for the individual. For late management, the choice of surgical techniques available range from neurolysis and nerve grafting to tendon and nerve transfers. The choice of technique utilized demands an in-depth understanding of the anatomy, patient demographics and the time elapsed since injury for optimized outcomes. This paper focuses on injuries to the radial, median and ulnar nerves, outlining the authors' approach to these injuries.Level of evidence: IV.

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.

Iatrogenic Nerve Injuries of the Upper Extremity: A Critical Analysis Review

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Iatrogenic nerve injuries may occur after any intervention of the upper extremity.

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Causes of iatrogenic nerve lesions include direct sharp or thermal injury, retraction, compression from implants or compartment syndrome, injection, patient positioning, radiation, and cast/splint application, among others.

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Optimal treatment of iatrogenic peripheral nerve lesions relies on early and accurate diagnosis.

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Advanced imaging modalities (e.g., ultrasound and magnetic resonance imaging) and electrodiagnostic studies aid and assist in preoperative planning.

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Optimal treatment of iatrogenic injuries is situation-dependent and depends on the feasibility of direct repair, grafting, and functional transfers.

Adductor Branch of Terminal Divisions of the Ulnar Nerve Transfer to the Thenar Motor Branch in a High Median Nerve Palsy: A Case Report

CASE

The author reports a 4-month-old high median nerve palsy in a 19-year-old man with right forearm fractures, stabilized with dynamic compression plates and screws. Surgical exploration revealed a large median nerve neuroma in the midarm that was excised, and the gap was bridged with sural nerve cable grafts. The extensor carpi radialis nerve was transferred to the anterior interosseous nerve in the forearm. The adductor branch of terminal divisions of the ulnar nerve was transferred to the thenar branch of the median nerve in the hand.

CONCLUSIONS

The adductor branch of ulnar nerve transfer to the thenar motor branch in high median nerve palsy efficiently restored thumb opposition in 10 months of follow-up. In addition, the patient's grasp and pinch improved, preserving thumb adduction.

Automatic range of motion measurement via smartphone images for telemedicine examination of the hand

BACKGROUND

Telemedicine support virtual consultations and evaluations in hand surgery for patients in remote areas during the COVID-19 era. However, traditional physical examination is challenging in telemedicine and it is inconvenient to manually measure the hand range of motion (ROM) from images or videos. Here, we propose an automatic method using the hand pose estimation technique, aiming to measure the hand ROM from smartphone images.

METHODS

Twenty-eight healthy volunteers participated in the study. An eight-hand gestures measurement protocol and the Google MediaPipe Hands were used to analyze images and calculate the ROM automatically. Manual goniometry was also performed according to the guideline of the American Medical Association. The correlation between the automatic and manual methods was analyzed by the intraclass correlation coefficient and Pearson correlation coefficient. The clinical acceptance was testified using Bland-Altman plots.

RESULTS

A total of 32 parameters of each hand were measured by both methods, and 1792 measurement results were compared. The mean difference between automatic and manual methods is -2.21 ± 9.29° in the angle measurement and 0.48 ± 0.48 cm in the distance measurement. The intraclass correlation coefficient of 75% of parameters was higher than 0.75, the Pearson correlation coefficient of 84% of parameters was over 0.6, and 40.6% of parameters reached well-accepted clinical agreements.

CONCLUSIONS

The proposed method provides a helpful protocol for automatic hand ROM measurement based on smartphone images and the MediaPipe Hands pose estimation technique. The automatic measurement is acceptable and comparable with existing methods, showing a possible application in the telemedicine examination of hand surgery.

Automatic detection of abnormal hand gestures in patients with radial, ulnar, or median nerve injury using hand pose estimation

Background

Radial, ulnar, or median nerve injuries are common peripheral nerve injuries. They usually present specific abnormal signs on the hands as evidence for hand surgeons to diagnose. However, without specialized knowledge, it is difficult for primary healthcare providers to recognize the clinical meaning and the potential nerve injuries through the abnormalities, often leading to misdiagnosis. Developing technologies for automatically detecting abnormal hand gestures would assist general medical service practitioners with an early diagnosis and treatment.

Methods

Based on expert experience, we selected three hand gestures with predetermined features and rules as three independent binary classification tasks for abnormal gesture detection. Images from patients with unilateral radial, ulnar, or median nerve injuries and healthy volunteers were obtained using a smartphone. The landmark coordinates were extracted using Google MediaPipe Hands to calculate the features. The receiver operating characteristic curve was employed for feature selection. We compared the performance of rule-based models with logistic regression, support vector machine and of random forest machine learning models by evaluating the accuracy, sensitivity, and specificity.

Results

The study included 1,344 images, twenty-two patients, and thirty-four volunteers. In rule-based models, eight features were finally selected. The accuracy, sensitivity, and specificity were (1) 98.2, 91.7, and 99.0% for radial nerve injury detection; (2) 97.3, 83.3, and 99.0% for ulnar nerve injury detection; and (3) 96.4, 87.5, and 97.1% for median nerve injury detection, respectively. All machine learning models had accuracy above 95% and sensitivity ranging from 37.5 to 100%.

Conclusion

Our study provides a helpful tool for detecting abnormal gestures in radial, ulnar, or median nerve injuries with satisfying accuracy, sensitivity, and specificity. It confirms that hand pose estimation could automatically analyze and detect the abnormalities from images of these patients. It has the potential to be a simple and convenient screening method for primary healthcare and telemedicine application.

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).

Use of Nerve Transfer Procedures for Motor and Sensory Restoration of a High Median Nerve Injury

High median nerve (HMN) injuries are unusual clinical conditions, but they generate significant disability of the affected extremities to perform even basic activities of daily living. Even though they can display different degrees of dysfunction due to overlapping innervation and musculature compensation, an early assessment of the existing functional deficits and a timely surgical approach can optimize the long-term outcome. The use of distal nerve transfer procedures has gained popularity since they reduce the distance between the injured zone and the disrupted targets, accelerate the nerve regeneration and subsequently optimize the postoperative motor and sensory recovery.

This report describes a patient with a significant segmental loss of the median nerve at the upper third of the left arm after a motor vehicle accident that caused multiple other injuries. The motor deficit of this injury was managed soon after the admission with extensor carpi radialis brevis (ECRB) nerve transfer to the anterior interosseous nerve (AIN). Subsequently, double side-to-side cross-palm nerve allografts between the ulnar and median nerves were utilized to restore the sensory deficit of the HMN lesion.

An important functional improvement was obtained with these nerve transfer procedures, and the patient successfully returned to the workforce without limitations. Other surgical options for motor and sensory reconstruction are briefly reviewed.

Five Reliable Nerve Transfers for the Treatment of Isolated Upper Extremity Nerve Injuries

LEARNING OBJECTIVES

After studying this article and accompanying videos, the participant should be able to: 1. Understand and apply the principles of nerve transfer surgery for nerve injuries. 2. Discuss important considerations when performing nerve transfers, such as aspects of surgical technique and perioperative decision-making. 3. Understand indications for end-to-end versus supercharged reverse end-to-side nerve transfers. 4. Understand an algorithm for treating nerve injuries to include the indications and surgical techniques of five nerve transfers commonly performed for the treatment of isolated upper extremity nerve injuries. 5. Understand the outcomes and postoperative management of the discussed nerve transfers.

SUMMARY

Nerve transfers are gaining wide acceptance because of their superior results in the management of many nerve injuries of the upper extremity. This article presents five nerve transfers for the treatment of isolated nerve injuries in the authors' upper extremity nerve practice that offer reliable results. Indications, surgical techniques, outcomes, and postoperative management are reviewed. To maximize functional outcomes in patients with nerve injuries, the treatment should be individualized to the patient, and the principles for nerve transfers as described herein should be considered.

Patterns of median nerve branching in the cubital fossa: implications for nerve transfers to restore motor function in a paralyzed upper limb

OBJECTIVE

The purpose of this study was to describe the anatomy of donor and recipient median nerve motor branches for nerve transfer surgery within the cubital fossa.

METHODS

Bilateral upper limbs of 10 fresh cadavers were dissected after dyed latex was injected into the axillary artery.

RESULTS

In the cubital fossa, the first branch was always the proximal branch of the pronator teres (PPT), whereas the last one was the anterior interosseous nerve (AIN) and the distal motor branch of the flexor digitorum superficialis (DFDS) on a consistent basis. The PT muscle was also innervated by a distal branch (DPT), which emerged from the anterior side of the median nerve and provided innervation to its deep head. The palmaris longus (PL) motor branch was always the second branch after the PPT, emerging as a single branch together with the flexor carpi radialis (FCR) or the proximal branch of the flexor digitorum superficialis. The FCR motor branch was prone to variations. It originated proximally with the PL branch (35%) or distally with the AIN (35%), and less frequently from the DPT. In 40% of dissections, the FDS was innervated by a single branch (i.e., the DFDS) originating close to the AIN. In 60% of cases, a proximal branch originated together with the PL or FCR. The AIN emerged from the posterior side of the median nerve and had a diameter of 2.3 mm, twice that of other branches. When dissections were performed between the PT and FCR muscles at the FDS arcade, we observed the AIN lying lateral and the DFDS medial to the median nerve. After crossing the FDS arcade, the AIN divided into: 1) a lateral branch to the flexor pollicis longus (FPL), which bifurcated to reach the anterior and posterior surfaces of the FPL; 2) a medial branch, which bifurcated to reach the flexor digitorum profundus (FDP); and 3) a long middle branch to the pronator quadratus. The average numbers of myelinated fibers within each median nerve branch were as follows (values expressed as the mean ± SD): PPT 646 ± 249; DPT 599 ± 150; PL 259 ± 105; FCR 541 ± 199; proximal FDS 435 ± 158; DFDS 376 ± 150; FPL 480 ± 309; first branch to the FDP 397 ± 12; and second branch to the FDP 369 ± 33.

CONCLUSIONS

The median nerve's branching pattern in the cubital fossa is predictable. The most important variation involves the FCR motor branch. These anatomical findings aid during nerve transfer surgery to restore function when paralysis results from injury to the radial or median nerves, brachial plexus, or spinal cord.

Effectiveness of electrophysical modalities in the sensorimotor rehabilitation of radial, ulnar, and median neuropathies: A meta-analysis

INTRODUCTION

People with ulnar, radial or median nerve injuries can present significant impairment of their sensory and motor functions. The prescribed treatment for these conditions often includes electrophysical therapies, whose effectiveness in improving symptoms and function is a source of debate. Therefore, this systematic review aims to provide an integrative overview of the efficacy of these modalities in sensorimotor rehabilitation compared to placebo, manual therapy, or between them.

METHODS

We conducted a systematic review according to PRISMA guidelines. We perform a literature review in the following databases: Biomed Central, Ebscohost, Lilacs, Ovid, PEDro, Sage, Scopus, Science Direct, Semantic Scholar, Taylor & Francis, and Web of Science, for the period 1980-2020. We include studies that discussed the sensorimotor rehabilitation of people with non-degenerative ulnar, radial, or median nerve injury. We assessed the quality of the included studies using the Risk of Bias Tool described in the Cochrane Handbook of Systematic Reviews of Interventions and the risk of bias across studies with the GRADE approach described in the GRADE Handbook.

RESULTS

Thirty-eight studies were included in the systematic review and 34 in the meta-analysis. The overall quality of evidence was rated as low or very low according to GRADE criteria. Low-level laser therapy and ultrasound showed favourable results in improving symptom severity and functional status compared to manual therapy. In addition, the low level laser showed improvements in pinch strength compared to placebo and pain (VAS) compared to manual therapy. Splints showed superior results to electrophysical modalities. The clinical significance of the results was assessed by effect size estimation and comparison with the minimum clinically important difference (MCID).

CONCLUSIONS

We found favourable results in pain relief, improvement of symptoms, functional status, and neurophysiological parameters for some electrophysical modalities, mainly when applied with a splint. Our results coincide with those obtained in some meta-analyses. However, none of these can be considered clinically significant.

TRIAL REGISTRATION

PROSPERO registration number CRD42020168792; https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=168792.

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.

Delayed Transfer of the Extensor Carpi Radialis Brevis Branch of the Radial Nerve to the Anterior Interosseous Nerve for Restoration of Thumb and Index Finger Flexion: Case Report

High median nerve injuries (HMNIs) are rare lesions involving the upper extremities and affect the median nerve from its origin to the emergence of the anterior interosseous nerve (AIN). Proximal reconstruction has long been considered the gold standard in treating HMNI, but thumb and index flexion and pinch and grip weakness are consistently not recovered. We report the surgical results of a patient affected by an HMNI with partial spontaneous recovery after a gunshot wound. AIN function was successfully restored in a delayed fashion by transferring the radial nerve branch to the extensor carpi radialis brevis to the AIN.

Reconstruction of a C7-T1 brachial plexus lower root injury by transferring multiple nerves and a free gracilis muscle: Case report

Lower-type brachial plexus injuries (BPI) are uncommon, and traditional reconstruction with tendon transfer procedures generally produce mediocre results. However, the advent of nerve transfers has rejuvenated the reconstructive options for peripheral nerve and spinal cord injuries. In this paper, we report the case 32 year-old patient with a C7-T1 avulsion BPI in whom multiple motor and sensory nerve transfers, combined with a free gracilis muscle flap transfer, were used to restore upper-limb functional defects. Five months after injury, several nerves were transferred (posterior division of the axillary nerve to motor nerve branches of the triceps, extensor carpi radialis brevis to flexor pollicis longus, supinator to the posterior interosseous nerve, brachialis to the ulnar nerve, and a cutaneous branch to the palm of the median nerve to the ulnar proper palmar digital nerve of the little finger). No complications occurred. M4 strength elbow extension, complete active finger extension and ulnar protective sensation were obtained. However, unsuccessful finger flexion reconstruction required a free gracilis muscle flap transfer motorized by the distal branch of the pronator teres, performed 43 months after the first surgery and resulting in complete finger flexion. Multiple nerve transfers might be a valid strategy for reconstructing lower BPIs, either in their early or late stage, which might be combined with a free gracilis muscle flap transfer.

TRANSFER OF THE RADIAL NERVE BRANCHES FOR THE TREATMENT OF THE ANTERIOR INTEROSSEOUS NERVE LESION: AN ANATOMICAL STUDY

Objective:

This anatomical study aimed to analyze the possibility of transferring the radial nerve branches destined to the brachioradialis (BR), extensor carpi radialis longus (ECRL), extensor carpi radialis brevis (ECRB), and supinator (SM) muscles to innervate the AIN.

Methods:

Ten limbs from five male cadavers were prepared by intra-arterial injection of a solution of 10% glycerol and formalin.

Results:

The presence of only one branch to the BR muscle was noted in 7 limbs and two branches were noted in three limbs. In two members of a common trunk with branch to the ECRL. In eight cases, we identified one branch for the ERLC and two branches in two cases. We identified only one branch for the ECRB, while in six limbs, two branches were noted, penetrating the muscular body at two different points. We identified at least two branches innervating the supinator muscle. The AIN was detached from the median nerve distal to the intercondylar line of the humerus. In seven limbs, it originated from the nervous fascicles of the posterior region of the median nerve and from the posterolateral fascicles in three limbs. The flexor pollicis longus and flexor digitorum profundus muscles received more than one branch of the AIN in all limbs.

Conclusion:

The radial nerve branches for the ECRL, ECRB, and supinator muscles can be transferred directly to the AIN or to one of its branches after intraneural dissection, without tension even in elbow movements. Level of Evidence IV; Case series.

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 Defects: Overviews of Practice in Europe

Many surgical techniques are available for the repair of peripheral nerve defects. Autologous nerve grafts are the gold standard for most clinical conditions. In selected cases, alternative types of reconstructions are performed to fill the nerve gap. Non-nervous autologous tissue-based conduits or synthetic ones are alternatives to nerve autografts. Allografts represent another new field of interest. Decision making in the treatment of nerve defects is based on timing of referral, level of the injury, type of lesion, and size of any gap. This review focuses on current clinical practice, influenced by the numerous new experimental researches.

Nerve injuries of the upper extremity and hand

A nerve injury has a profound impact on the patient’s daily life due to the impaired sensory and motor function, impaired dexterity, sensitivity to cold as well as eventual pain problems.

To perform an appropriate treatment of nerve injuries, a correct diagnosis must be made, where the injury is properly classified, leading to an optimal surgical approach and technique, where timing of surgery is also important for the outcome.

Knowledge about the nerve regeneration process, where delicate processes occur in neurons, non-neuronal cells (i.e. Schwann cells) and other cells in the peripheral as well as the central nervous systems, is crucial for the treating surgeon.

The surgical decision to perform nerve repair and/or reconstruction depends on the type of injury, the condition of the wound as well as the vascularity of the wound.

To reconnect injured nerve ends, various techniques can be used, which include both epineurial and fascicular nerve repair, and if a nerve defect is caused by the injury, a nerve reconstruction procedure has to be performed, including bridging the defect using nerve-grafts or nerve transfer techniques.

The patients must be evaluated properly and regularly after the surgical procedure and appropriate rehabilitation programmes are useful to improve the final outcome.

Cite this article: EFORT Open Rev 2017;2. DOI: 10.1302/2058-5241.2.160071. Originally published online at www.efortopenreviews.org

Sensory deficits after a radial nerve injury

BACKGROUND

The aim of our study was to objectively test sensibility on the dorsal side of the hand in patients with radial nerve injury, to document deficits and to detect if surgery for sensory reconstruction is needed.

METHODS

Nineteen patients of mean age 31 ± 10 years were examined at a mean of 26.4 ± 27.8 months post radial nerve injury. Sensory mechanical thresholds on the dorsal surface of the hand were evaluated using Semmes-Weinstein monofilaments. Sensation was considered significantly impaired when there was no perception of a 2.0 gr. Semmes-Weinstein filament. Nociception was evaluated using Adson forceps.

RESULTS

Five patients had normal 2.0 monofilament perception. Two of these five also had normal perception of the lighter 0.05 monofilament. In nine patients, zones of impaired sensibility were restricted to the first web space. In combined radial and musculocutaneous nerve lesions, the zone of impaired sensibility extended to the dorsum of the third metacarpus and occasionally to the dorsal aspect of the thumb. This zone averaged being five times the size as in isolated radial nerve injuries. On average, the zone of decreased 0.05 monofilament perception was six times the size detected for the 2.0 monofilament. No patient had complete anesthesia over the dorsum of the hand. No patient complained about pain or numbness. Only one patient among four with a combined radial and musculocutaneous nerve injury required sensory reconstruction.

CONCLUSIONS

Minimal sensory abnormalities should be expected after a radial nerve injury. Patients likely neither warrant nor request sensory reconstruction.