Nerve transfers for restoration of finger flexion in patients with tetraplegia

Supinator to Anterior Interosseous Nerve Transfer to Restore Finger Flexion in Spinal Cord and Peripheral Nerve Injury

PURPOSE

Restoration of pinch and grasp is a chief concern of patients with cervical spinal cord injury or peripheral nerve injury involving the anterior interosseous nerve (AIN). We hypothesize that supinator nerve-to-AIN (Sup-AIN) nerve transfer is a viable option for AIN neurotization.

METHODS

We performed a retrospective review of patients who received Sup-AIN. Reported outcomes included Medical Research Council strength of the flexor digitorum profundus and flexor pollicis longus and passive range of digit motion. Patients with <12 months of follow-up were excluded.

RESULTS

Eleven patients underwent Sup-AIN, eight with peripheral nerve injury, and three with spinal cord injury. Three patients were excluded because of insufficient follow-up. Average follow-up was 17 months (range: 12-25 months). Six patients had M4 recovery (75%), one patient had M3 recovery (12.5%), and one did not recover function because of severe stiffness (12.5%). We observed no complications or donor site morbidity in our patients.

CONCLUSIONS

The Sup-AIN nerve transfer is an effective option to restore digital flexion in patients with peripheral nerve injury or spinal cord injury involving the AIN motor distribution. In comparison to previously described extensor carpi radialis brevis to AIN and brachialis to AIN nerve transfers, Sup-AIN offers the benefits of a more expendable donor nerve and shorter regenerative distance, respectively. The one failed Sup-AIN in our series highlights the importance of patient selection.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Impact of Upper Limb Motor Recovery on Functional Independence After Traumatic Low Cervical Spinal Cord Injury

Cervical spinal cord injury (SCI) causes devastating loss of upper limb function and independence. Restoration of upper limb function can have a profound impact on independence and quality of life. In low-cervical SCI (level C5-C8), upper limb function can be restored via reinnervation strategies such as nerve transfer surgery. The translation of recovered upper limb motor function into functional independence in activities of daily living (ADLs), however, remains unknown in low cervical SCI (i.e., tetraplegia). The objective of this study was to evaluate the association of patterns in upper limb motor recovery with functional independence in ADLs. This will then inform prioritization of reinnervation strategies focused to maximize function in patients with tetraplegia. This retrospective study performed a secondary analysis of patients with low cervical (C5-C8) enrolled in the SCI Model Systems (SCIMS) database. Baseline neurological examinations and their association with functional independence in major ADLs-i.e., eating, bladder management, and transfers (bed/wheelchair/chair)-were evaluated. Motor functional recovery was defined as achieving motor strength, in modified research council (MRC) grade, of ≥ 3 /5 at one year from ≤ 2/5 at baseline. The association of motor function recovery with functional independence at one-year follow-up was compared in patients with recovered elbow flexion (C5), wrist extension (C6), elbow extension (C7), and finger flexion (C8). A multi-variable logistic regression analysis, adjusting for known factors influencing recovery after SCI, was performed to evaluate the impact of motor function at one year on a composite outcome of functional independence in major ADLs. Composite outcome was defined as functional independence measure score of 6 or higher (complete independence) in at least two domains among eating, bladder management, and transfers. Between 1992 and 2016, 1090 patients with low cervical SCI and complete neurological/functional measures were included. At baseline, 67% of patients had complete SCI and 33% had incomplete SCI. The majority of patients were dependent in eating, bladder management, and transfers. At one-year follow-up, the largest proportion of patients who recovered motor function in finger flexion (C8) and elbow extension (C7) gained independence in eating, bladder management, and transfers. In multi-variable analysis, patients who had recovered finger flexion (C8) or elbow extension (C7) had higher odds of gaining independence in a composite of major ADLs (odds ratio [OR] = 3.13 and OR = 2.87, respectively, p < 0.001). Age 60 years (OR = 0.44, p = 0.01), and complete SCI (OR = 0.43, p = 0.002) were associated with reduced odds of gaining independence in ADLs. After cervical SCI, finger flexion (C8) and elbow extension (C7) recovery translate into greater independence in eating, bladder management, and transfers. These results can be used to design individualized reinnervation plans to reanimate upper limb function and maximize independence in patients with low cervical SCI.

A Fresh Cadaver Study on the Innervation of Brachioradialis and Extensor Carpi Radialis Longus Muscles

PURPOSE

Distal nerve transfers have revolutionized peripheral nerve surgery by allowing the transfer of healthy motor nerves to paralyzed ones without causing additional morbidity. Radial nerve branches to the brachialis (Ba), brachioradialis (Br), and extensor carpi radialis longus (ECRL) muscles have not been investigated in fresh cadavers.

METHODS

The radial nerve and its branches were dissected in 34 upper limbs from 17 fresh cadavers. Measurements were taken to determine the number, origin, length, and diameter of the branches. Myelinated fiber counts were obtained through histological analysis.

RESULTS

The first branch of the radial nerve at the elbow was to the Ba muscle, followed by the branches to the Br and ECRL muscles. The Ba and Br muscles consistently received single innervation. The ECRL muscle showed varying innervation patterns, with one, two, or three branches. The branches to the Br muscles originated from the anterior side of the radial nerve, whereas the branches to the Ba and ECRL muscles originated from the posterior side. The average myelinated fiber counts favored the nerve to Br muscle over that to the ECRL muscle, with counts of 542 versus 350 and 568 versus 302 observed in hematoxylin and eosin and neurofilament staining, respectively.

CONCLUSIONS

This study provides detailed anatomical insights into the motor branches of the radial nerve to the Ba, Br, and ECRL muscles.

CLINICAL RELEVANCE

Understanding the anatomy of the radial nerve branches at the elbow is of utmost importance when devising a reconstructive strategy for upper limb paralysis. These findings can guide surgeons in selecting appropriate donor or recipient nerves for nerve transfer in cases of high tetraplegia and lower-type brachial plexus injuries.

Long-term functional recovery in C5-C6 avulsions treated with distal nerve transfers

BACKGROUND

In patients suffering from traction lesions of the brachial plexus, complete C5 and/or C6 root avulsion patients with C7 root preservation are relatively uncommon occurrences, but represent excellent candidates for surgical treatment, with satisfactory results. Shoulder abduction and extra-rotation, elbow flexion and forearm supination are lost functions restorable with surgical treatment.

METHODS

This single-center, prospective observational study involved a series of 27 young adults with C5 and/or C6 root complete avulsion and C7 preservation, which underwent surgical repair with double or triple nerve transfer.

RESULTS

Patients recovered a useful elbow flexion. Electromyographic and clinical signs of biceps reinnervation were observed in each UN-MC nerve transfer. The abduction strength recovery was M5 in 10 patients, M4 in 14 patients and M3 in 3 patients. The external rotation strength recovery was M5 in 4 patients, M4 in 18 patients, M3 in 3 patients and M2 in 2 patients. The elbow flection strength was M5 in 5 patients, M4 in 15 patients and M3 in 7 patients. Elbow extension was preserved in all cases.

CONCLUSIONS

The concept of 'peripheral rewiring procedures' represents an advance in the repair of the peripheral nerve injuries. Triple nerve transfer can be nowadays considered a standard treatment for isolated C5-C6 avulsions. We report our experience with the second-biggest casuistry in the literature on patients treated with this technique. We consider our outcome concerning functional recovery to be satisfying and comparable to data reported in the literature.

Pulp-to-Pulp Pinch Reconstruction in a Tetraplegic Patient Utilizing Nerve and Tendon Transfers: A Case Report

In tetraplegia, hand reconstruction is of high priority. Key pinch reconstruction has been advocated for tetraplegia hand reconstruction because of the lack of donors for nerve and tendon transfers. We report a patient with mid-cervical tetraplegia who underwent nerve and tendon transfers in the right and left upper limbs seven months post-injury to reconstruct hand function. The particularity of our case resides in the left-hand thumb and index pulp-to-pulp reconstruction. For this, we transferred the nerve to the supinator to the posterior interosseous nerve and the nerve to the extensor carpi radialis brevis to the anterior interosseous nerve. During a second surgery, we relieved clawing by transferring the split flexor digitorum superficialis of the middle and ring fingers, motored by the brachioradialis, to the extensor apparatus of all fingers. Finally, to achieve better thumb palmar abduction, we osteotomized the scaphoid tubercle and fixed it to the distal radius while maintaining thenar muscle attachments. Five years after surgery, the patient was able to grasp and release small objects placed on a table after becoming left-handed. Here, we demonstrated that pinch-to-pinch reconstruction is possible, which increased hand use in daily activities, especially during eating and grabbing small objects over the table.

Assessing an Online Patient Decision Aid about Upper Extremity Reconstructive Surgery for Cervical Spinal Cord Injury: Pilot Testing Knowledge, Decisional Conflict, and Acceptability

Background. While nerve and tendon transfer surgery can restore upper extremity function and independence after midcervical spinal cord injury, few individuals (∼14%) undergo surgery. There is limited information regarding these complex and time-sensitive treatment options. Patient decision aids (PtDAs) convey complex health information and help individuals make informed, preference-consistent choices. The purpose of this study is to evaluate a newly created PtDA for people with spinal cord injury who are considering options to optimize upper extremity function. Methods. The PtDA was developed by our multidisciplinary group based on clinical evidence and the Ottawa Decision Support Framework. A prospective pilot study enrolled adults with midcervical spinal cord injury to evaluate the PtDA. Participants completed surveys about knowledge and decisional conflict before and after viewing the PtDA. Acceptability measures and suggestions for further improvement were also solicited. Results. Forty-two individuals were enrolled and completed study procedures. Participants had a 20% increase in knowledge after using the PtDA (P < 0.001). The number of participants experiencing decisional conflict decreased after viewing the PtDA (33 v. 18, P = 0.001). Acceptability was high. To improve the PtDA, participants suggested adding details about specific surgeries and outcomes. Limitations. Due to the COVID-19 pandemic, we used an entirely virtual study methodology and recruited participants from national networks and organizations. Most participants were older than the general population with a new spinal cord injury and may have different injury causes than typical surgical candidates. Conclusions. A de novo PtDA improved knowledge of treatment options and reduced decisional conflict about reconstructive surgery among people with cervical spinal cord injury. Future work should explore PtDA use for improving knowledge and decisional conflict in the nonresearch, clinical setting.

Highlights

People with cervical spinal cord injury prioritize gaining upper extremity function after injury, but few individuals receive information about treatment options.A newly created patient decision aid (PtDA) provides information about recovery after spinal cord injury and the role of traditional tendon and newer nerve transfer surgery to improve upper extremity upper extremity function.The PtDA improved knowledge and decreased decisional conflict in this pilot study.Future work should focus on studying dissemination and implementation of the ptDA into clinical practice.

Reconstruction of Prehension in C7-T1 Brachial Plexus Injury with Nerve and Tendon Transfers: A Case Report

CASE

Reconstruction of function in C7-T1 lower brachial plexus injury requires restoration of finger flexion and extension with nerve or tendon transfers. A 22-year-old man was involved in an all-terrain vehicle rollover accident. First-stage nerve transfers included extensor carpi radialis brevis to the anterior interosseous nerve and supinator to the posterior interosseous nerve. After second-stage (15 months later) side-to-side flexor digitorum profundus and Camitz abductorplasty, he was able to achieve tripod pinch and power grip.

CONCLUSION

A combined approach with nerve transfers followed by tendon transfers allows restoration of prehension in lower BPI while preserving the brachialis as a backup donor.

Quantifying Donor Deficits Following Nerve Transfer Surgery in Tetraplegia

PURPOSE

Nerve transfer (NT) surgery can improve function in people with cervical spinal cord injury (SCI). However, the impact of donor nerve deficits remains unclear. The purpose of this study was to quantify donor deficits experienced by individuals with cervical SCI following NT.

METHODS

This prospective single-arm, comparative study included people with SCI undergoing upper extremity NTs. Myometry was used to assess muscle strength at baseline and follow-up. The Spinal Cord Independence Measure was used to measure the ability to perform activities of daily living.

RESULTS

Ten individuals underwent 20 NTs to restore elbow extension (donor, posterior deltoid; n = 2), hand opening (donor, supinator; n = 7), and hand closing (donor, brachialis; n = 11). Shoulder abduction strength decreased (-5.6% at early and -4.5% late follow-up) in the elbow extension NT. Wrist extension strength decreased at early (-46.9% ± 30.3) and increased by late (76.4% ± 154.0) follow-up in the hand opening NT. No statistically significant change in elbow flexion strength was noted in the hand closing NT. Spinal Cord Independence Measure scores did not change significantly between baseline and early postoperative follow-up; they improved at late follow-up.

CONCLUSIONS

Use of expendable donor nerves with redundant function to perform NT surgery has relatively little impact on strength or capacity to perform activities of daily living, even in the unique and highly vulnerable SCI population. Early, temporary loss in wrist extension strength can be seen after the supinator to posterior interosseous nerve transfer. This study offers quantitative data about possible diminution of donor function after NT, enabling hand surgeons to better counsel individuals contemplating upper extremity reconstruction.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic I.

Upper Limb Nerve Transfer Surgery in Patients With Tetraplegia

IMPORTANCE

Cervical spinal cord injury (SCI) causes devastating loss of upper extremity function and independence. Nerve transfers are a promising approach to reanimate upper limbs; however, there remains a paucity of high-quality evidence supporting a clinical benefit for patients with tetraplegia.

OBJECTIVE

To evaluate the clinical utility of nerve transfers for reanimation of upper limb function in tetraplegia.

DESIGN, SETTING, AND PARTICIPANTS

In this prospective case series, adults with cervical SCI and upper extremity paralysis whose recovery plateaued were enrolled between September 1, 2015, and January 31, 2019. Data analysis was performed from August 2021 to February 2022.

INTERVENTIONS

Nerve transfers to reanimate upper extremity motor function with target reinnervation of elbow extension and hand grasp, pinch, and/or release.

MAIN OUTCOMES AND MEASURES

The primary outcome was motor strength measured by Medical Research Council (MRC) grades 0 to 5. Secondary outcomes included Sollerman Hand Function Test (SHFT); Michigan Hand Outcome Questionnaire (MHQ); Disabilities of Arm, Shoulder, and Hand (DASH); and 36-Item Short Form Health Survey (SF-36) physical component summary (PCS) and mental component summary (MCS) scores. Outcomes were assessed up to 48 months postoperatively.

RESULTS

Twenty-two patients with tetraplegia (median age, 36 years [range, 18-76 years]; 21 male [95%]) underwent 60 nerve transfers on 35 upper limbs at a median time of 21 months (range, 6-142 months) after SCI. At final follow-up, upper limb motor strength improved significantly: median MRC grades were 3 (IQR, 2.5-4; P = .01) for triceps, with 70% of upper limbs gaining an MRC grade of 3 or higher for elbow extension; 4 (IQR, 2-4; P < .001) for finger extensors, with 79% of hands gaining an MRC grade of 3 or higher for finger extension; and 2 (IQR, 1-3; P < .001) for finger flexors, with 52% of hands gaining an MRC grade of 3 or higher for finger flexion. The secondary outcomes of SHFT, MHQ, DASH, and SF36-PCS scores improved beyond the established minimal clinically important difference. Both early (<12 months) and delayed (≥12 months) nerve transfers after SCI achieved comparable motor outcomes. Continual improvement in motor strength was observed in the finger flexors and extensors across the entire duration of follow-up.

CONCLUSIONS AND RELEVANCE

In this prospective case series, nerve transfer surgery was associated with improvement of upper limb motor strength and functional independence in patients with tetraplegia. Nerve transfer is a promising intervention feasible in both subacute and chronic SCI.

The Anatomy of Nerve Transfers Used in Tetraplegic Hand Reconstruction

PURPOSE

To evaluate the anatomy of nerve transfers used to reconstruct wrist extension, hand opening, and hand closing in tetraplegic patients.

METHODS

Nerve transfers were completed on 18 paired cadaveric upper limbs. The overlap of donor and recipient nerves was measured, as well as the distance to the target muscle. Axons were counted in each nerve and branch, with the axon percentage calculated by dividing the donor nerve count by that of the recipient.

RESULTS

Transfers with overlap of the donor and recipient nerve were from the radial nerve branch to extensor carpi radialis brevis to anterior interosseous nerve (AIN) and from the branch(es) to supinator to posterior interosseous nerve. The extensor carpi radialis brevis to AIN had the shortest distance to the target, with the branch to brachialis to AIN being the longest. The nerve transfers for wrist extension had the highest axon percentage. Of the transfers for hand closing, the brachialis to AIN had the highest axon percentage, and the branch to brachioradialis to AIN had the lowest.

CONCLUSIONS

The anatomical features of nerve transfers used in tetraplegic hand reconstruction are variable. Differences may help explain clinical outcomes.

CLINICAL RELEVANCE

This study demonstrates which nerve transfers may be anatomically favorable for restoring hand function in tetraplegic patients.

Contemporary Approaches to Peripheral Nerve Surgery

“State of the Art” Learning Objectives: This manuscript serves to provide the reader with a general overview of the contemporary approaches to peripheral nerve reconstruction as the field has undergone considerable advancement over the last 3 decades. The learning objectives are as follows: To provide the reader with a brief history of peripheral nerve surgery and some of the landmark developments that allow for current peripheral nerve care practices. To outline the considerations and management options for the care of patients with brachial plexopathy, spinal cord injury, and lower extremity peripheral nerve injury. Highlight contemporary surgical techniques to address terminal neuroma and phantom limb pain. Review progressive and future procedures in peripheral nerve care, such as supercharge end-to-side nerve transfers. Discuss rehabilitation techniques for peripheral nerve care.

An Examination of Utilization Rates Over Time of Nerve and Tendon Transfers in Canada to Improve Upper Limb Function in Cervical Spinal Cord Injury

Introduction: Upper limb function loss in cervical spinal cord injury (SCI) contributes to substantial disability, and negatively impacts quality of life. Nerve transfer and tendon transfer surgery can provide improved upper limb function. This study assessed the utilization of nerve and tendon transfer surgery for individuals with tetraplegia in Canada. Methods: Data from the Canadian Institute for Health Information's Discharge Abstracts Database and the National Ambulatory Care Reporting System were used to identify the nerve and tendon transfer procedures performed in individuals with tetraplegia (2004-2020). Cases were identified using cervical SCI ICD-10-CA codes and Canadian Classification of Intervention codes for upper extremity nerve and tendon transfers. Data on sex, age at time of procedure, province, and hospital stay duration were recorded. Results: From 2004 to 2020, there were ≤80 nerve transfer procedures (81% male, mean age 38.3 years) and 61 tendon transfer procedures (78% male, mean age 45.0 years) performed (highest in Ontario and British Columbia). Using an estimate of 50% eligibility, an average of 1.3% of individuals underwent nerve transfer and 1.0% underwent tendon transfer. Nerve transfers increased over time (2004-2009, n = <5; 2010-2015, n = 27; 2016-2019, n = 49) and tendon transfers remained relatively constant. Both transfer types were performed as day-surgery or single night stay. Conclusions: Nerve and tendon transfer surgery to improve upper limb function in Canadians with tetraplegia remains low. This study highlights a substantial gap in care for this vulnerable population. Identification of barriers that prevent access to care is required to promote best practice for upper extremity care.

Spontaneous Motor Recovery after Cervical Spinal Cord Injury: Issues for Nerve Transfer Surgery Decision Making

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To quantify spontaneous upper extremity motor recovery between 6 and 12 months after spinal cord injury (SCI) to help guide timing of nerve transfer surgery to improve upper limb function in cervical SCI.

SETTING

Nineteen European SCI rehabilitation centers.

METHODS

Data was extracted from the European Multicenter Study of SCI database for individuals with mid-level cervical SCI (N = 268). Muscle function grades at 6 and 12 months post-SCI were categorized for analysis.

RESULTS

From 6 to 12 months after SCI, spontaneous surgically-relevant recovery was limited. Of all limbs (N = 263) with grade 0-2 elbow extension at 6 months, 4% regained grade 4-5 and 11% regained grade 3 muscle function at 12 months. Of all limbs (N = 380) with grade 0-2 finger flexion at 6 months, 3% regained grade 4-5 and 5% regained grade 3 muscle function at 12 months.

CONCLUSION

This information supports early (6 month) post-injury surgical consultation and evaluation. With this information, individuals with SCI can more fully engage in preference-based decision-making about surgical intervention versus continued rehabilitation and spontaneous recovery to gain elbow extension and/or hand opening and closing.

A Prediction Model for Various Treatment Pathways of Upper Extremity in Tetraplegia

Upper extremity function is essential for the autonomy in patients with cervical spinal cord injuries and consequently a focus of the rehabilitation and treatment efforts. Routinely, an individualized treatment plan is proposed to the patient by an interprofessional team. It dichotomizes into a conservative and a surgical treatment pathway. To select an optimal pathway, it is important to define predictors that substantiate the treatment strategy. Apart from standard assessments (Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI), the manual muscle test (MRC), and lower motoneuron integrity of key actuators for hand function performed by motor point (MP) mapping might serve as a possible predictor. Type of damage (upper motor neuron (UMN) or lower motor neuron (LMN) lesion) influences hand posture and thus treatment strategy as positioning and splinting of fingers, hands, arms, and surgical reconstructive procedures (muscle-tendon or nerve transfers) in choice and timing of intervention. For this purpose, an analysis of a database comprising 220 patients with cervical spinal cord injury is used. It includes ISNCSCI, MRC, and MP mapping of defined muscles at selected time points after injury. The ordinal regression analysis performed indicates that MP and ASIA impairment scale (AIS) act as predictors of muscle strength acquisition. In accordance with the innervation status defined by MP, electrical stimulation (ES) is executed either via nerve or direct muscle stimulation as a supplementary therapy to the traditional occupational and physiotherapeutic treatment methods. Depending on the objective, ES is applied for motor learning, strengthening, or maintenance of muscle contractile properties. By employing ES, hand and arm function can be predicted by MP and AIS and used as the basis for providing an individualized treatment plan.

Pre-operative electrodiagnostic planning for upper limb peripheral nerve transfers in cervical spinal cord injury: A Narrative Review

Peripheral nerve transfer (PNT) to improve upper limb function following cervical spinal cord injury (SCI) involves the transfer of supralesional donor nerves under voluntary control to intralesional or sublesional lower motor neurons not under voluntary control. Appropriate selection of donor and recipient nerves and surgical timing impact functional outcomes. While the gold standard of nerve selection is intra-operative nerve stimulation, preoperative electrodiagnostic (EDX) evaluation may help guide surgical planning. Currently there is no standardized preoperative EDX protocol. This study reviews the EDX workup preceding peripheral nerve transfer surgery in cervical SCI, and proposes an informed EDX protocol to assist with surgical planning. The PICO (Population, Intervention, Comparison, Outcome) framework was used to formulate relevant MeSH terms and identify published cases of PNT in cervical SCI in Medline, Embase, CINAHL, and Emcare databases in the last 10 years. The electrodiagnostic techniques evaluating putative donor nerves, recipient nerve branches, time-sensitivity of nerve transfer and other electrophysiological parameters were summarized to guide creation of a preoperative EDX protocol. Needle electromyography (EMG) was the most commonly used EDX technique to identify healthy donor nerves. Although needle EMG has also been used on recipient nerves, compound muscle action potential (CMAP) amplitudes may provide a more accurate determination of recipient nerve health and time-sensitivity for nerve transfer. While there has been progress in pre-surgical EDX evaluation, EMG and NCS approaches are quite variable, and each has limitations in their utility for pre-operative planning. There is need for standardization in the EDX evaluation preceding peripheral nerve transfer surgery to assist with donor and recipient nerve selection, surgical timing and to optimize outcomes. Based on results of this review, herein we propose the PreSCIse (PRotocol for Electrodiagnosis in SCI Surgery of the upper Extremity) pre-operative EDX panel to achieve said goals through an interdisciplinary and patient-centered approach. This article is protected by copyright. All rights reserved.

Surgery to Restore Upper Extremity Function in Tetraplegia-Preferences for Early and Frequent Access to Information

INTRODUCTION

People with cervical spinal cord injury (SCI) identify improving upper extremity (UE) function as a top priority. In addition to comprehensive rehabilitation, UE surgeries, including nerve and tendon transfers, enhance function. However, barriers exist to disseminating information about surgical options to enhance UE function.

OBJECTIVE

To assess the experiences and preferences of people with cervical SCI and their caregivers in accessing information about surgery to enhance UE function.

DESIGN

Prospective cohort study. Participants were followed for 24 months and completed up to three interviews.

SETTING

Tertiary care at academic and affiliated Veterans Administration Health Care Centers.

PARTICIPANTS

Adults with cervical SCI (n=35) ages 18 to 80 years with mid-cervical SCI American Spinal Injury Association Impairment Scale A, B, or C (at least six months post-injury) and their caregivers (n=23) were eligible to participate. Participants were enrolled in three groups: nerve transfer, tendon transfer, or no UE reconstructive surgery.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE

Semi-structured interviews about surgical knowledge and experiences.

RESULTS

Data were analyzed and three themes were identified. First, providing information about UE surgical options early post-injury was recommended. The acute or inpatient rehabilitation phases of recovery were the preferred times to receive surgical information. Second, challenges with information dissemination were identified. Participants learned about UE surgery through independent research, medical provider interactions, or peers. Third, peers were identified as valuable resources for SCI needs and surgical information.

CONCLUSIONS

Following cervical SCI, information about UE reconstructive surgeries should be a standard component of education during rehabilitation. An increased understanding of the reconstructive options available to improve UE function is necessary to educate stakeholders. Future research is needed to support the development of strategies to effectively present surgical information to individuals with SCI and healthcare providers. This article is protected by copyright. All rights reserved.

Donor activation focused rehabilitation approach to hand closing nerve transfer surgery in individuals with cervical level spinal cord injury

STUDY DESIGN

Case Series.

OBJECTIVES

To describe the donor activation focused rehabilitation approach (DAFRA) in the setting of the hand closing nerve transfers in cervical spinal cord injury (SCI) so that therapists may apply it to treatment of individuals undergoing this procedure.

SETTING

United States of America-Academic Level 1 Trauma Center.

METHODS

We reviewed the records of individuals with cervical SCI who underwent nerve transfer to restore hand closing and post-surgery DAFRA therapy at our institution. The three post-surgery phases of DAFRA included (1) early phase (0-12 months) education, limb preparation, and donor activation exercises, (2) middle phase (12-24 months) volitional recipient muscle activation and (3) late phase (18 + months) strengthening and incorporation of motion in activities of daily living.

RESULTS

Subtle gains in hand closing were first observed at a mean of 8.4 months after hand closing nerve transfer surgery. Remarkable improvements including discontinuation of assistive devices, independence with feeding and urinary function, and measurable grip were observed. Function continued to improve slowly for one to two more years.

CONCLUSIONS

A deliberate, slow-paced (monthly for >2 years post-surgery) and incremental therapy program-DAFRA-can be used to improve outcomes after nerve transfer to restore hand closing in cervical SCI.

SPONSORSHIP

This work was made possible by funding from the Craig H. Neilsen Foundation Spinal Cord Injury Research on the Translation Spectrum (SCIRTS) Grant: Nerve Transfers to Restore Hand Function in Cervical Spinal Cord Injury (PI: Ida Fox).

Functional outcome after transfer of brachialis on anterior interosseous and supinator on posterior interosseous nerves: A preliminary report

OBJECTIVE

Traumatic spinal cord injury (SCI) resulting in tetraplegia is a leading cause of morbidity among young adults worldwide and its management remains challenging. Restoring hand function in these patients must be considered a top priority with great impact on their quality of life (QOL); although nerve and tendon transfer have been extensively described, type of procedure to be chosen is not standardized and few studies have determined the functional outcome of those procedure and their impact on QOL is still poorly assessed. We report a preliminary retrospective study regarding feasibility and functional outcomes of nerve transfer procedures including bilateral brachialis nerve on anterior interosseous nerve (AIN) and supinator branch on posterior interosseous nerve (PIN) for hand reanimation following SCI focusing on the impact of these procedures on QOL.

METHODS

We performed a retrospective study involving patient sustained SCI and underwent nerve transfer of brachialis branch from musculocutaneous nerve on AIN and supinator branch from the trunk of the radial nerve on the PIN. We included 11 patients (14 limbs) with traumatic SCI resulting in C4 level tetraplegia in five patients, C5 in four and C6 and C7 in one case each, with a median age of 31.5 years underwent surgery at a median of 10 months after injury; including both transfers in 10 cases and AIN reanimation only in one. Functional assessment including medical research council (MCR) grade, graded redefined assessment of strength sensation and prehension (GRASSP) and spinal cord independence measure (SCIM) were performed at least 12 months follow up.

RESULTS

Thirteen PIN innervated muscles achieved an MRC score ≥3/5 whereas AIN supplied muscles in 5 out of 15. GRASSP qualitative measure improved from a baseline value of 1 to 2, while quantitative measure passed from 1 to 3 after 12 months; the difference was statistically significant (p = .005 and p = .008, respectively). SCIM self-care sub-score also statistically significant improved from 3 to 4 at 12 months (p = .016). No complication or donor morbidity occurred.

CONCLUSIONS

Functional performance has been significantly improved by nerve transfer procedures 1 year after surgery. Nerve transfers may represent a valuable option for the restoration of the hand function in patients with tetraplegia with minor or no morbidity.

Nerve Transfer of Brachialis Branch to Anterior Interosseus Nerve Using In Situ Lateral Antebrachial Cutaneous Nerve Graft in Tetraplegia

PURPOSE

Reconstruction of finger motion is a therapeutic goal in tetraplegic patients. Although nerve transfer of the brachialis branch of the musculocutaneous nerve to the anterior interosseus nerve has been previously described, this results in unreliable reinnervation because the donor nerve is proximal to the target muscle. We describe an alternative technique in which nerve transfer is performed using the lateral antebrachial cutaneous nerve as a vascular in situ nerve graft. The clinical results are reported.

METHODS

Nine upper limbs of 6 patients (mean age 25 years) with tetraplegia were subjected to brachialis-to-anterior interosseus nerve transfer using the lateral antebrachial cutaneous nerve as a vascular in situ nerve graft, at a mean of 6 months after injury. Additional supinator branch transfer to the posterior interosseous nerve was performed for 6 upper limbs and to the flexor digitorum superficialis motor branch for 1 upper limb.

RESULTS

At a mean of 2 years of follow-up, thumb and finger flexion strength scored M3-M4 in 5 of the 9 limbs according to the Medical Research Council scale. Key pinch and grip pinch averaged 0.6 kg (range, 0-1.0 kg) and 2.2 kg (range, 0-8 kg), respectively. No donor-site deficit was observed.

CONCLUSIONS

Brachialis-to-anterior interosseus nerve transfer with an in situ lateral antebrachial cutaneous nerve graft can be used to reconstruct thumb and finger flexion in tetraplegic patients. Combined with supinator-to- posterior interosseous nerve transfer, simultaneous active extension of the fingers can be achieved.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Patient perspectives and self-rated knowledge of nerve transfer surgery for restoring upper limb function in spinal cord injury

BACKGROUND

Nerve transfer surgery has the potential to restore upper limb function in patients with spinal cord injury (SCI); however, there has been limited exploration of patient perception of nerve transfer.

OBJECTIVE

To explore the perspectives of patients with chronic SCI (>2 years from injury) on nerve transfer surgery, and to determine if an educational intervention improved participants' perceived knowledge levels about the procedure.

DESIGN

Mixed-methods study including qualitative semi-structured interviews and self-reported rating scales. Pre- and post-interviews were completed following an educational presentation.

SETTING

Two local SCI clinics.

PARTICIPANTS

Ten patients with chronic traumatic SCI and neurological level of injury C3-C7 (motor complete or incomplete), recruited via snowball sampling (six male, four female).

INTERVENTION

An educational slide presentation on nerve transfer concepts.

MAIN OUTCOME MEASURES

The primary study outcome measure is the participants' responses to interview questions. The secondary study outcome measure is their self-reported knowledge levels of nerve transfer before and after education.

RESULTS

Regaining upper limb function was a priority for all participants. Although most participants had heard of nerve transfer, none were offered it at the time of their SCI, and only two stated that they had any peers who had undergone the procedure. The educational module significantly increased self-rated scores on understanding of nerve transfer (p < .05). Although all participants were open to nerve transfer after the educational module, they described weighing different factors, including (1) potential for loss versus gain of function, (2) inadequate knowledge about nerve transfer, (3) recovery time, and (4) determining their eligibility for the surgery.

CONCLUSIONS

These findings suggest that people with SCI have limited understanding of nerve transfer as a potential option and would benefit from educational opportunities to help them make informed decisions. This study may inform the development of patient resources to improve pre-surgical consultation and informed decision-making.

Plasticity of the Central Nervous System Involving Peripheral Nerve Transfer

Peripheral nerve injury can lead to partial or complete loss of limb function, and nerve transfer is an effective surgical salvage for patients with these injuries. The inability of deprived cortical regions representing damaged nerves to overcome corresponding maladaptive plasticity after the reinnervation of muscle fibers and sensory receptors is thought to be correlated with lasting and unfavorable functional recovery. However, the concept of central nervous system plasticity is rarely elucidated in classical textbooks involving peripheral nerve injury, let alone peripheral nerve transfer. This article is aimed at providing a comprehensive understanding of central nervous system plasticity involving peripheral nerve injury by reviewing studies mainly in human or nonhuman primate and by highlighting the functional and structural modifications in the central nervous system after peripheral nerve transfer. Hopefully, it will help surgeons perform successful nerve transfer under the guidance of modern concepts in neuroplasticity.

Selective transfer of nerve to supinator to restore digital extension in central cord syndrome: An anatomical study and a case report

BACKGROUND

Nerve transfers are increasingly used to restore upper extremity function in patients with spinal cord injury. However, the role of nerve transfers for central cord syndrome is still being established. The purpose of this study is to report the anatomical feasibility and clinical use of nerve transfer of supinator motor branches (NS) to restore finger extension in a central cord syndrome patient.

MATERIALS AND METHODS

The posterior interosseous nerve (PIN), its superficial division, and branches were dissected in 14 fresh cadavers, with a mean age of 65 (58-79). Measurements included number and length of branches of donor and recipient, diameters, regeneration distance from coaptation site to motor entry point and axonal counts. A NS transfer to extensor carpi ulnaris (ECU), extensor digiti quinti (EDQ) and extensor digitorum communis (EDC) was performed in a 28-year-old patient, with central cord syndrome after a motorcycle accident, who did not recover active finger extension at 10 months post injury.

RESULTS

The PIN consistently divided into a deep and superficial branch between 1.5 cm proximal to, and 2 cm distal to the distal boundary of the supinator. The superficial branch provided a first common branch to the ECU and EDQ. In 12/14 dissections, the EDC was innervated by a 4 cm long branch that entered the muscle on its radial deep surface. In all cases, the superficial branch of the PIN could be separated in a retrograde fashion from the PIN and coapted with NS. The mean myelinated fiber count in nerve to EDC was 401 ± 190 compared to 398 ± 75 in the NS. At 48 months after surgery, with the wrist at neutral, the patient recovered full metacarpophalangeal extension scoring M4. Supination was preserved with the elbow extended or flexed.

CONCLUSIONS

Restoration of finger extension in central cord syndrome is possible with a selective transfer of the NS to EDC, and is anatomically feasible with a short regeneration distance and favorable axonal count ratio.

Improving hand function after spinal cord injury

Nerve transfer surgery has expanded reconstructive options for restoring upper extremity function following spinal cord injury. By adding new motor donors to the pool already available through tendon transfers, the effectiveness of treatment should improve. Planning which procedures and in which order to perform, along with their details must be delineated. To meet these demands, refined diagnostics are needed, along with awareness of the remaining challenges to restore intrinsic muscle function and to address spasticity and its consequences. This article summaries recent advances in surgical reanimation of upper extremity motor control, together with an overview of the development of neuro-prosthetic and neuromodulation techniques to modify recovery or substitute for functional losses after spinal cord injuries.

Optimizing the timing of peripheral nerve transfers for functional re-animation in cervical spinal cord injury: a conceptual framework

Loss of upper extremity function following spinal cord injury (SCI) can have devastating consequences on quality of life. Peripheral nerve transfer surgery aims to restore motor control of upper extremities following cervical SCI and is poised to revolutionize surgical management in this population. The surgery involves dividing an expendable donor nerve above the level of the spinal lesion and coapting it to a recipient nerve arising from the lesional or infralesional segment of the injured cord. In order to maximize outcomes in this complex patient population, refinements in surgical technique need to be integrated with principles of spinal cord medicine and basic science. Deciding on the ideal timing of nerve transfer surgery is one aspect of care that is critical to maximizing recovery and has received very little attention to date in the literature. This complex topic is reviewed, with a focus on expectations for spontaneous recovery within upper motor neuron components of the injury, balanced against the need for expeditious reinnervation for lower motor neuron elements of the injury. The discussion also considers the case of a patient with C6 motor complete SCI where myotomes without electrodiagnostic evidence of denervation spontaneously improved by 6 months post-injury, thereby adjusting the surgical plan. The relevant concepts are integrated into a clinical algorithm with recommendations that consider maximal opportunity for spontaneous clinical improvement post-injury while avoiding excessive delays that may adversely affect patient outcomes.

Optimizing nerve transfer surgery in tetraplegia: clinical decision making based on innervation patterns in spinal cord injury

OBJECTIVE

Nerve transfers are increasingly being utilized in the treatment of chronic tetraplegia, with increasing literature describing significant improvements in sensorimotor function up to years after injury. However, despite technical advances, clinical outcomes remain heterogenous. Preoperative electrodiagnostic testing is the most direct measure of nerve health and may provide prognostic information that can optimize preoperative patient selection. The objective of this study in patients with spinal cord injury (SCI) was to determine various zones of injury (ZOIs) via electrodiagnostic assessment (EDX) to predict motor outcomes after nerve transfers in tetraplegia.

METHODS

This retrospective review of prospectively collected data included all patients with tetraplegia from cervical SCI who underwent nerve transfer at the authors' institution between 2013 and 2020. Preoperative demographic data, results of EDX, operative details, and postoperative motor outcomes were extracted. EDX was standardized into grades that describe donor and recipient nerves. Five zones of SCI were defined. Motor outcomes were then compared based on various zones of innervation.

RESULTS

Nineteen tetraplegic patients were identified who underwent 52 nerve transfers targeting hand function, and 75% of these nerve transfers were performed more than 1 year postinjury, with a median interval to surgery following SCI of 24 (range 8-142) months. Normal recipient compound muscle action potential and isolated upper motor neuron injury on electromyography (EMG) were associated with greater motor recovery. When nerve transfers were stratified based on donor EMG, greater motor gains were associated with normal than with abnormal donor EMG motor unit recruitment patterns. When nerve transfers were separated based on donor and recipient nerves, normal flexor donors were more crucial than normal extensor donors in powering their respective flexor recipients.

CONCLUSIONS

This study elucidates the relationship of the preoperative innervation zones in SCI patients to final motor outcomes. EDX studies can be used to tailor surgical therapies for nerve transfers in patients with tetraplegia. The authors propose an algorithm for optimizing nerve transfer strategies in tetraplegia, whereby understanding the ZOI and grade of the donor/recipient nerve is critical to predicting motor outcomes.

Evaluation of Functional Independence in Cervical Spinal Cord Injury: Implications for Surgery to Restore Upper Limb Function

PURPOSE

To help individuals make informed choices regarding the optimal type and timing of restorative surgical treatment for cervical spinal cord injury (SCI), more precise information is needed on their ability to perform activities of daily living. The goal of this work was to describe functional independence achieved by individuals with differing levels of cervical SCI.

METHODS

Using the comprehensive European Multicenter Study of Spinal Cord Injury dataset, analysis was undertaken of individuals with traumatic SCI, motor-level C5-C8. Data on feeding, bladder management, and transfers (bed to wheelchair) were compared between individuals with different levels of injury. Subgroup analyses of symmetrical and asymmetrical SCI and between complete and incomplete SCI were performed. The impact of age, sex, and time postinjury on functional independence was ascertained.

RESULTS

Data were available for individuals with symmetrical (n = 204) and asymmetrical (n = 95) patterns of SCI. Independence with feeding, urinary function, and transfer ability was increased in individuals with strong finger flexion. Unexpectedly, the presence of strong elbow extension did not uniformly result in the ability to transfer independently. There was no change in any of the analyzed activities between 6 and 12 months postinjury.

CONCLUSIONS

People with cervical SCI who gain finger flexion have greater independence with feeding, urinary, and transfer activities. Restoration of finger flexion should be a reconstructive priority for individuals with midcervical-level SCI.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Nerve transfer rehabilitation in tetraplegia: Comprehensive assessment and treatment program to improve upper extremity function before and after nerve transfer surgery, a case report

CONTEXT

A 28-year-old male, sustained a traumatic Spinal Cord Injury (SCI) in January 2015, and was classified as AIS A, neurological level of injury (NLI) C4. As an inpatient at the SCI rehabilitation unit, he underwent multidisciplinary assessment involving SCI specialists, peripheral nerve surgeons, psychologists, occupational and physical therapists. Team consensus determined he was a candidate for nerve transfer surgery to improve upper extremity function. The patient undertook a pre-surgical neurorehabilitation program of 3 months duration. Surgery was performed bilaterally at 11 and 13 months after SCI (right and left arm respectively).

FINDINGS

Upon completion of surgical procedures, the patient underwent an intensive post-surgical rehabilitation program based on established goals, with follow-up every 3 months, up to 24 months after the surgery. Notable improvements were wheelchair propulsion, the ability to relieve pressure, grasp, pinch, and release an object. Standardized measures for SCI individuals (SCIM-III, CUE-Q, LiSAT-9 and UEMS) showed significant improvements.

CLINICAL RELEVANCE

Nerve transfers in tetraplegia are an underused technique. The benefits of surgery along with an intensive neurorehabilitation program, can improve independence and function in daily living activities for a properly selected group of individuals.

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.

Nerve transfers in tetraplegia: a review and practical guide

INTRODUCTION

Spinal cord injury (SCI) may lead to tetraplegia. Several nerve transfers have been successfully used for the restoration of the upper limb in tetraplegia. Reconstruction of an upper limb is individualized based on the functional level. In this study, the authors reviewed nerve transfers based on the injury level for the restoration of upper limb function in tetraplegia.

EVIDENCE ACQUISITION

We performed this study to review nerve transfers in tetraplegia by searching MEDLINE and EMBASE databases to identify relevant articles published through December 2020. We selected studies that reported cases in tetraplegia and extracted information on demographic data, clinical characteristics, operative details, and strength outcomes based on each injury level after surgery.

EVIDENCE SYNTHESIS

Total of 29 journal articles reporting on 275 nerve transfers in 172 upper limbs of 121 patients were included in the review. The mean time between SCI and nerve transfer surgery was 21.37 months (range: 4-156 months), and the follow-up time was 21.34 months (range: 3-38 months). The best outcomes were achieved for the restoration of wrist/finger extension and elbow extension.

CONCLUSIONS

Nerve transfer can provide a new function in tetraplegic patients' upper limbs to improve daily living activities. The type of surgical procedure should be performed based on the functional level of SCI and the individual's needs. Functional recovery occurs more in extensor muscles than flexors. Nerve transfer is a promising option in the reconstruction of upper limb function in tetraplegia.

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.

Clinical guidelines for neurorestorative therapies in spinal cord injury (2021 China version)

Treatment of spinal cord injury (SCI) remains challenging. Considering the rapid developments in neurorestorative therapies for SCI, we have revised and updated the Clinical Therapeutic Guidelines for Neurorestoration in Spinal Cord Injury (2016 Chinese version) of the Chinese Association of Neurorestoratology (Preparatory) and China Committee of International Association of Neurorestoratology. Treatment of SCI is a systematic multimodal process that aims to improve survival and restore neurological function. These guidelines cover real-world comprehensive neurorestorative management of acute, subacute, and chronic SCI and include assessment and diagnosis, pre-hospital first aid, treatment, rehabilitation, and complication management.

Estudo anatômico dos ramos motores do nervo radial no antebraço

Objetivo Analisar as variações anatômicas dos ramos motores do nervo radial na região do cotovelo. Foram avaliadas a origem, curso, comprimento, ramificações, pontos motores e relações com estruturas vizinhas.

Materiais e Métodos Foram dissecados 30 membros de 15 cadáveres adultos, preparados por injeção intra-arterial de uma solução de glicerina e formol a 10%.

Resultados O primeiro ramo do nervo radial no antebraço foi para o músculo braquiorradial (BR), que se origina proximalmente à divisão do nervo radial em ramo superficial do nervo radial (RSNR) e nervo interósseo posterior (NIP) em todos os membros. Os ramos para o músculo extensor radial longo do carpo (ERLC) se desprenderam do nervo radial proximalmente à sua divisão em 26 membros, em 2, nos pontos de divisão, em outros 2, do NIP. Em seis, os ramos para os músculos BR e ERLC originavam-se de um tronco comum. Identificamos a origem do ramo para o músculo extensor radial curto do carpo (ERCC) no NIP em 14 membros, no RSNR em 12, e no nervo radial em apenas 4. O ramo para o músculo supinador originou-se do NIP em todos os membros.

Conclusão O conhecimento da anatomia dos ramos motores do nervo radial é importante quando se realizam procedimentos cirúrgicos na região, como a abordagem do terço proximal e da cabeça do rádio, a liberação das síndromes compressivas do nervo interósseo posterior e do túnel radial, as transferências nervosas distais, e para entender a ordem de recuperação da função muscular após uma lesão nervosa.

Nerves transfers for functional hand recovery in traumatic lower brachial plexopathy

Background:

Distal nerve transfers are an innovative modality for the treatment of C8-T1 brachial plexus lesions. The purpose of this case series is to report the authors’ results with hand restoration function by nerve transfer in patients with lower brachial plexus injury.

Methods:

Three consecutive nerve transfers were performed in a series of 11 patients to restore hand function after injury to the lower brachial plexus: brachialis motor branch to anterior interosseous nerve (AIN) and supinator branch to the posterior interosseous nerve (PIN) in a first surgical procedure, and AIN to pronator quadratus branch of ulnar nerve between 4 and 6 months later.

Results:

In all, 11 male patients underwent 33 surgical procedures. Time between brachial plexus injury and surgery was a mean of 11 months (range 4–13 months). Postoperative follow-up ranged from 12 to 24 months. We observed recovery of M3 or better finger flexion strength (AIN) and wrist extension (PIN) in 8 of the 11 surgically treated upper limbs. These patients recovered full thumb and finger extension between 6 and 12 months of surgery, without significant loss of donor function.

Conclusion:

Nerve transfers represent a way of restoring volitional control of upper extremity function in patients with C8-T1 brachial plexus injury.

Upper Limb Reconstruction in Tetraplegic Patients: A Primer for Spinal Cord Injury Specialists

Cervical spinal cord injury (SCI) often causes debilitating loss of function of the upper limb. Upper extremity reconstruction surgery can restore some of the upper limb function in tetraplegic patients with SCI. The procedures are typically muscle-tendon unit transfer surgeries, which redistribute the remaining functional muscles to restore active elbow extension, key grip, and finger grasping. In addition to the tendon transfer surgeries, nerve transfers have emerged recently and are showing promising results. However, despite more than half of the tetraplegic patients can benefit from upper limb surgery, only a few of them receive the procedures. This missed opportunity may be due to the lack of communication between SCI specialists and hand surgeons, or the lack of awareness of such options among the specialists and patients. In this review, we provide a basic overview of upper limb reconstruction in tetraplegic patients with target audience of SCI specialists for their better understanding of the basic concept of surgery and information for patient consultation before referring to hand surgeons.

Upper and lower motor neuron lesions in tetraplegia: implications for surgical nerve transfer to restore hand function

Nerve transfers (neurotizations) performed under optimal conditions can restore some voluntary control in muscles of the upper extremities in patients with tetraplegia. However, the type of motoneuron lesions in target muscles for nerve transfers influences the functional outcome. Using standardized maps of motor point topography, surface electrical stimulation reliably defines the kind and extent of motoneuron lesion in the selected muscles. In a muscle with an intact lower motor motoneuron, nerve transfers can often successfully reinnervate the chosen key muscle. Conversely, in a lower motoneuron lesion, the nerve transfer outcome is less predictable. However, direct muscle stimulation appears to ameliorate the morphological precondition, a finding that necessitates new preoperative approaches to optimize reinnervation in denervated/partially denervated muscles. Therefore, understanding the impact of electrical stimulation in diagnostics, prognostics, and treatments of upper limbs in tetraplegia is critical for neurotization procedures.

Upper-Extremity Reconstruction in Tetraplegia: A Critical Analysis Review

Management of tetraplegia should be individualized to a patient's particular deficiencies and functional goals. Surgical decision-making for upper-extremity reconstruction in patients with tetraplegia relies on a thorough physical examination to determine which nerves and muscles remain under volitional control with adequate strength for transfer. Peripheral nerve transfers, either in conjunction with or in place of traditional tendon transfers, enable providers to offer an expanded set of surgical options for patients with tetraplegia who are seeking upper-extremity reconstruction. All upper-extremity reconstructive efforts should be carefully considered with regard to their potential effects on the availability of future reconstructive efforts.

Hand Reconstruction in Children with Spinal Cord Injury

Comprehensive programs for children who sustain traumatic spinal cord injury should incorporate optimizing hand and upper extremity function along with the other traditional pillars of rehabilitation. Children's smaller anatomy, open growth plates, and future skeletal growth, combined with the age-related psychosocial impact of these injuries, require protocols suited to these age-related issues. There is a role for surgical reconstruction, as is the case for adults with traumatic tetraplegia, and surgical outcomes are equally beneficial and long lasting. Strict adherence to surgical indications, and surgical strategies and protocols that incorporate their age-related challenges, are the keys to successful management.

Combined nerve and tendon transfer to restore elbow extension in tetraplegic patients: surgical technique and case report

INTRODUCTION

In individuals with tetraplegia, elbow extension is critical for overhead activities, weight shifting, independent transfers, and to perform self-care tasks such as eating. At present, restoration of elbow extension in tetraplegic patients can be performed using either tendon or nerve transfers. Each procedure presents several advantages and limitations that must be discussed with the potential surgical candidate, based on remaining muscular functions and functional goals.

CASE PRESENTATION

We propose a novel combined technique of both tendon and nerve transfer to restore active elbow extension by transferring the posterior deltoid tendon to the triceps tendon and the branch of teres minor nerve to the long head of the triceps nerve. Techniques were performed from the same shoulder posterior surgical approach.

DISCUSSION

This surgical technique can add the benefits of each tendon and nerve transfer, leading to a reduction of failure rates, with more predictable outcomes.

Evaluation for Late Nerve Transfer Surgery in Spinal Cord Injury: Predicting the Degree of Lower Motor Neuron Injury

PURPOSE

Nerve transfer surgery is used to restore upper extremity function following cervical spinal cord injury (SCI) with substantial variation in outcomes. The injury pattern in SCI is complex and can include isolated upper motor neuron (UMN) and combined UMN/lower motor neuron (LMN) dysfunction. The purpose of the study was to determine the most effective diagnostic technique for determining suitable candidates for nerve transfer surgery in SCI.

METHODS

Medical records were reviewed of patients who had nerve transfers to restore upper extremity function in SCI. Data collected included (1) preoperative clinical examination and electrodiagnostic testing; (2) intraoperative neuromuscular stimulation (NMS); and (3) nerve histopathology. Preoperative, intraoperative, and postoperative data were compared to identify predictors of isolated UMN versus combined UMN/LMN injury patterns.

RESULTS

The study sample included 22 patients with 50 nerve transfer surgeries and included patients ranging from less than 1 year to over a decade post-SCI. Normal recipient nerve conduction studies (NCS) before surgery corresponded to the intraoperative presence of recipient NMS and postoperative histopathology that showed normal nerve architecture. Conversely, abnormal recipient NCS before surgery corresponded with the absence of recipient NMS during surgery and patterns of denervation on postoperative histopathology. Normal donor preoperative manual muscle testing corresponded with the presence of donor NMS during surgery and normal nerve architecture on postoperative histopathology. An EMG of corresponding musculature did not correspond with intraoperative donor or recipient NMS or histopathological findings.

CONCLUSIONS

NCS better predict patterns of injury in SCI than EMG. This is important information for clinicians evaluating people for late nerve transfer surgery even years post-SCI.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

Priorities of desired functional recovery in Indian spinal cord injury patients

BACKGROUND

Spinal cord injuries (SCI) affect various functions and therefore the Quality of life (QOL) of these patients. Regaining even partial function can lead to improved QOL; making it crucial to know which functions are most important for these patients.

MATERIAL AND METHODS

This prompted us to conduct a survey in which subjects were asked to rank seven functions in order of importance to improve their quality of life. Survey was administered by personal interview of patients in different spinal injury rehabilitation centers across India.

RESULTS

A total of 112 patients completed the survey. Regaining arm and hand function was ranked as first priority by quadriplegics while bowel/bladder function and walking movements were ranked as 2nd and 3rd priority. Paraplegics ranked return of walking movements as their first priority, bladder/bowel recovery as second and trunk strength/sexual function as 3rd priority.

CONCLUSION

This knowledge empowers us to focus our research on what is most important for their QOL.

Evidence for efficacy of new developments in reconstructive upper limb surgery for tetraplegia

Nerve transfers are increasingly utilized for upper limb reconstruction in tetraplegia. We reviewed the literature for results achieved by nerve transfers for elbow extension, wrist control and finger and thumb flexion and extension. Muscle strength grading was the only outcome measure consistently reported. The results confirm that nerve transfers can effectively reanimate muscles in selected cases, with comparable strength with those achieved with tendon transfer for elbow extension but inferior strength for finger and thumb flexion. Transfer of supinator nerve branches to the posterior interosseous nerve appears to be reliable and offers increased span and better hand opening than is observed after tendon transfers. Only one publication demonstrated how reinnervation of muscles with nerve transfers translated into improved function, activity and participation for patients. More prospective studies, using standardized outcome measures, are needed to define the precise role of nerve transfers.

Development of 3D-printed myoelectric hand orthosis for patients with spinal cord injury

BACKGROUND

Spinal cord injury (SCI) is a severe medical condition affecting the hand and locomotor function. New medical technologies, including various wearable devices, as well as rehabilitation treatments are being developed to enhance hand function in patients with SCI. As three-dimensional (3D) printing has the advantage of being able to produce low-cost personalized devices, there is a growing appeal to apply this technology to rehabilitation equipment in conjunction with scientific advances. In this study, we proposed a novel 3D-printed hand orthosis that is controlled by electromyography (EMG) signals. The orthosis was designed to aid the grasping function for patients with cervical SCI. We applied this hand exoskeleton system to individuals with tetraplegia due to SCI and validated its effectiveness.

METHODS

The 3D architecture of the device was designed using computer-aided design software and printed with a polylactic acid filament. The dynamic hand orthosis enhanced the tenodesis grip to provide sufficient grasping function. The root mean square of the EMG signal was used as the input for controlling the device. Ten subjects with hand weakness due to chronic cervical SCI were enrolled in this study, and their hand function was assessed before and after wearing the orthosis. The Toronto Rehabilitation Institute Hand Function Test (TRI-HFT) was used as the primary outcome measure. Furthermore, improvements in functional independence in daily living and device usability were evaluated.

RESULTS

The newly developed orthosis improved hand function of subjects, as determined using the TRI-HFT (p < 0.05). Furthermore, participants obtained immediate functionality on eating after wearing the orthosis. Moreover, most participants were satisfied with the device as determined by the usability test. There were no side effects associated with the experiment.

CONCLUSIONS

The 3D-printed myoelectric hand orthosis was intuitive, easy to use, and showed positive effects in its ability to handle objects encountered in daily life. This study proved that combining simple EMG-based control strategies and 3D printing techniques was feasible and promising in rehabilitation engineering.

TRIAL REGISTRATION

Clinical Research Information Service (CRiS), Republic of Korea. KCT0003995. Registered 2 May 2019 - Retrospectively registered.

Clinical Neurorestorative Therapeutic Guidelines for Spinal Cord Injury (IANR/CANR version 2019)

Functional restoration after spinal cord injury (SCI) is one of the most challenging tasks in neurological clinical practice. With a view to exploring effective neurorestorative methods in the acute, subacute, and chronic phases of SCI, “Clinical Therapeutic Guidelines of Neurorestoration for Spinal Cord Injury (China Version 2016)” was first ​proposed in 2016 by the Chinese Association of Neurorestoratology (CANR). Given the rapid advances in this field in recent years, the International Association of Neurorestoratology (IANR) and CANR formed and approved the “Clinical Neurorestorative Therapeutic Guidelines for Spinal Cord Injury (IANR/CANR version 2019)”. These guidelines mainly introduce restoring damaged neurological structure and functions by varying neurorestorative strategies in acute, subacute, and chronic phases of SCI. These guidelines can provide a neurorestorative therapeutic standard or reference for clinicians and researchers in clinical practice to maximally restore functions of patients with SCI and improve their quality of life.

The translational potential of this article

This guideline provided comprehensive management strategies for SCI, which contains the evaluation and diagnosis, pre-hospital first aid, treatments, rehabilitation training, and complications management. Nowadays, amounts of neurorestorative strategies have been demonstrated to be benefit in promoting the functional recovery and improving the quality of life for SCI patients by clinical trials. Also, the positive results of preclinical research provided lots of new neurorestorative strategies for SCI treatment. These promising neurorestorative strategies are worthy of translation in the future and can promote the advancement of SCI treatments.

Expanding traditional tendon-based techniques with nerve transfers for the restoration of upper limb function in tetraplegia: a prospective case series

BACKGROUND

Loss of upper extremity function after cervical spinal cord injury greatly affects independence, including social, vocational, and community engagement. Nerve transfer surgery offers an exciting new option for the reanimation of upper limb function in tetraplegia. The aim of this study was to evaluate the outcomes of nerve transfer surgery used for the reanimation of upper limb function in tetraplegia.

METHODS

In this prospective case series, we consecutively recruited people of any age with early (<18 months post-injury) cervical spinal cord injury of motor level C5 and below, who had been referred to a single centre for upper extremity reanimation and were deemed suitable for nerve transfer. All participants underwent single or multiple nerve transfers in one or both upper limbs, sometimes combined with tendon transfers, for restoration of elbow extension, grasp, pinch, and hand opening. Participants were assessed at 12 months and 24 months post-surgery. Primary outcome measures were the action research arm test (ARAT), grasp release test (GRT), and spinal cord independence measure (SCIM).

FINDINGS

Between April 14, 2014, and Nov 22, 2018, we recruited 16 participants (27 limbs) with traumatic spinal cord injury, among whom 59 nerve transfers were done. In ten participants (12 limbs), nerve transfers were combined with tendon transfers. 24-month follow-up data were unavailable for three patients (five limbs). At 24 months, significant improvements from baseline in median ARAT total score (34·0 [IQR 24·0-38·3] at 24 months vs 16·5 [12·0-22·0] at baseline, p<0·0001) and GRT total score (125·2 [65·1-154·4] vs 35·0 [21·0-52·3], p<0·0001) were observed. Mean total SCIM score and mobility in the room and toilet SCIM score improved by more than the minimal detectable change and the minimal clinically important difference, and the mean self-care SCIM score improved by more than the minimal detectable change between baseline and 24 months. Median Medical Research Council strength grades were 3 (IQR 2-3) for triceps and 4 (IQR 4-4) for digital extensor muscles after 24 months. Mean grasp strength at 24 months was 3·2 kg (SD 1·5) in participants who underwent distal nerve transfers (n=5), 2·8 kg (3·2) in those who had proximal nerve transfers (n=9), and 3·9 kg (2·4) in those who had tendon transfers (n=8). There were six adverse events related to the surgery, none of which had any ongoing functional consequences.

INTERPRETATION

Early nerve transfer surgery is a safe and effective addition to surgical techniques for upper limb reanimation in tetraplegia. Nerve transfers can lead to significant functional improvement and can be successfully combined with tendon transfers to maximise functional benefits.

FUNDING

Institute for Safety, Compensation, and Recovery Research (Australia).

Motor Point Topography of Fundamental Grip Actuators in Tetraplegia: Implications in Nerve Transfer Surgery

The differentiation between an upper motoneuron (UMN) lesion and lower motoneuron (LMN) lesion of forearm muscles in patients with tetraplegia is critical for the choice of treatment strategy. Specifically, the M. pronator teres (PT), M. flexor digitorum profundus III (FDPIII), and M. flexor pollicis longus (FPL) were studied since they represent key targets in nerve transfer surgery to restore grasp function. Forearm muscles of 24 patients with tetraplegia were tested bilaterally with electrical stimulation (ES) to determine whether UMN or LMN lesion was present. For detecting and testing the nerve stimulation points, a standardized mapping was developed and clinically applied. The relationship between the anatomical segmental spinal innervation and the innervation pattern tested by ES was determined. The data of 44 arms were analyzed. For PT, 19 arms showed an intact UMN, 18 arms an UMN lesion, and seven arms partial denervation. For FDPIII, three arms demonstrated an intact UMN, 26 arms an UMN lesion, 10 arms partial denervation, and five arms denervation. For FPL, two arms presented an intact UMN, 16 arms an UMN lesion, 12 arms partial denervation, and 14 arms denervation. A total of 20.1% ES tested muscles were partially denervated. In four patients, only one arm could be tested because of surgery-related limitations. According to the level of lesion and the segmental spinal innervation, most denervated muscles were present in the patient group C6 to C8. The ES, together with the developed mapping system, is reliable and can be recommended for standardized testing in surgery and rehabilitation. It offers the possibility to detect if and to what extent UMN and LMN lesions are present for the target muscles. It allows for refined pre-operative diagnostics and prognostics in spinal cord injury neurotization surgery.