Seventh cervical nerve root transfer from the contralateral healthy side for treatment of brachial plexus root avulsion

Neuroendoscopy-Assisted Modified Anterior Approach for Contralateral Cervical 7 Nerve Transfer: A Cadaveric Study

BACKGROUND

This study aims to investigate a safer and more minimally invasive method for transferring the contralateral C7 nerve in the treatment of central spastic paralysis of the upper limb, while also providing anatomic data to support this approach.

METHODS

Eight anatomic specimens from the head and neck were utilized: 4 dry specimens were used to measure anatomic data, whereas the other 4 fresh specimens were used to simulate the transposition of the contralateral C7 nerve for observing bilateral nerve anastomosis. Relevant anatomic landmarks and their surrounding relationships were examined using a neuroendoscope, and anatomic data were subsequently measured and analyzed.

RESULTS

The modified anterior vertebral approach, assisted by a neuroendoscope, can expose both the affected and contralateral C7 nerve roots, vertebral arteries, and the middle trunk of the brachial plexus on the contralateral side. It can also facilitate the completion of bilateral C7 nerve transfer within the affected side's longus colli muscle tunnel, with tension-free suturing achieved without the need for nerve bridging. Measurement results from dry specimens: The angle between the C7 nerve and the spine was 63.6±3.8 degrees, the horizontal distance from the vertebral artery to the midline of the spine was 2.44±0.54 cm, and the horizontal distance from the C7 horizontal vertebral artery to the midline of the spine, as measured by imaging, was 2.46±0.14 cm. The difference between the 2 measurements was not statistically significant (P>0.05). The measured nerve displacement in fresh specimens was 4.62±0.37 cm, and the length of the C7 nerve was 7.87±0.55 cm.

CONCLUSION

The experiments confirmed that the neuroendoscopy-assisted modified anterior vertebral approach is a simple, effective, and safe method for contralateral C7 nerve transfer. This approach involves a short nerve transfer distance and does not necessitate nerve transplantation. It may serve as a safe and effective surgical method for treating central upper limb spastic paralysis. The anatomic parameters obtained in this study will aid in the implementation of this procedure.

Clinical assessment in brachial plexus injury surgery: systematic review and proposal for integrated evaluation among different medical departments

BACKGROUND

Brachial plexus injury (BPI) surgery involves diversity in surgical departments including plastic surgery, hand surgery, orthopedic surgery, and neurosurgery. There is a clear scarcity in terms of unified guidelines for outcome publications due to the absence of collaboration or consensus development between departments. This study aims to identify relevant clinical parameters and their standardized presentation to address this gap.

METHODS

A systematic review was carried out to identify the clinical outcomes and methodological characteristics of the studies published regarding BPI surgery according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). Advanced search in PubMed was performed using the MeSH terms "Brachial Plexus Injury" (Major topic) AND "Surgery" (Subheading), obtaining a total of 2382 articles. Statistical analysis was performed, and the study was registered with the PROSPERO ID: CDR42022353785.

RESULTS

A total of 136 articles were included to the systematic review, and 11,949 patients were evaluated in different clinical outcomes according to the preferences of the authors. Traumatic events around the world are the most common cause of injury. The clinical components most reported were: British Medical Research Council in motor at 82.3%, visual analog scale in pain was 21.3%, sensitive components at 26.4%, and quality of life in 16.1% of the cases.

CONCLUSIONS

The lack of standardized clinical trials highlights the need to increase the level of evidence with the aim to identify clinical evaluations among all the diverse departments to provide optimal care for BPI treatment.

Functional outcomes following nerve transfers for shoulder and elbow reanimation in brachial plexus injuries: a 10-year retrospective study

Brachial plexus injuries are rare but highly disabling, with major implications for upper limb function and quality of life. Nerve transfers have emerged as a key reconstructive technique, particularly valuable in cases where primary repair or grafting is unfeasible or delayed. This retrospective study analysed functional outcomes following nerve transfers in 37 patients with brachial plexus injury. Motor recovery was assessed using the Medical Research Council scale. Patients were stratified by age, timing of surgery, injury severity, and type of nerve transfer performed. The majority of our cohort consisted of male adults, predominantly injured in motorcycle accidents, while pediatric cases were mostly due to obstetrical trauma. For shoulder reanimation, all patients received spinal accessory to suprascapular nerve transfer, with a subset also undergoing medial triceps branch of the radial nerve to axillary nerve transfer. These techniques resulted in 85.3% of patients achieving shoulder function recovery with M3 or M4 muscle strength, with combined procedures leading exclusively to M3 or M4 muscle strength. For elbow flexion restoration, surgical approaches included intercostal to musculocutaneous nerve transfer, ulnar and median fascicles to musculocutaneous nerve transfer, contralateral C7 to musculocutaneous nerve transfer with ulnar graft, and spinal accessory to musculocutaneous nerve transfer with sural nerve graft. Root grafting procedures using sural nerve grafts or nerve conduits were employed in three pediatric patients. Overall, 84.38% of patients achieved elbow flexion recovery with M3 or M4 muscle strength. These findings reinforce the utility of nerve transfers as a cornerstone in the surgical management of brachial plexus injury.

Contralateral C7 nerve transfer to three recipient nerves-An optional surgical method in total brachial plexus avulsion combined with accessory and phrenic nerve injury

PURPOSE

The purpose of this study is to present our long-term follow-up outcomes on the use of the contralateral C7 (CC7) transfer to reinnervate three recipient nerves in patients with total brachial plexus avulsion (BPA).

METHODS

We retrospectively reviewed data from 13 patients with total BPA. All patients were diagnosed with phrenic and accessory nerve injury on the affected side. Five patients were 20 years or younger, and eight patients were older than 20 years at the time of surgery. In the first stage, the entire CC7 was harvested and transferred to the pedicled ulnar nerve and the suprascapular nerve with a sural nerve graft. The ulnar nerve was transferred to the median nerve and biceps branch in the second stage about 4 to 8 months after the first stage. The British Medical Research Council (MRC) grading system was used for motor and sensory assessment.

RESULTS

Of the 13 cases, 11 obtained equal or more M3 of shoulder abduction strength, and the effective rate of recovery was 84.62%. The effective rates were 53.85% (7/13) for shoulder external rotation, 84.62% (11/13) for elbow flexion, 61.54% (8/13) for wrist and finger flexion, and 53.85% (7/13) in median nerve area sensation. The recovery of median nerve function in the younger age group was significantly better than in the older group (p < 0.05).

CONCLUSIONS

The use of CC7 transfer for simultaneous repair of the suprascapular nerve, median nerve, and biceps branch may become an option for the treatment of total BPA combined with phrenic nerve and spinal accessory nerve injuries.

Research trends and hotspots in the surgical treatment of peripheral nerve injuries of the upper limb from 2000 to 2024: a bibliometric visualization study

Purpose

Surgical treatment plays a crucial role in the management of peripheral nerve injuries of the upper limb, but little bibliometric analysis has been conducted on it. This study was aimed to examine the global trends and hotspots in the field of Peripheral nerve injuries of the upper limb.

Methods

Publications on the surgical treatment of peripheral nerve injuries of the upper limb in the Web of Science database were collected between 2000 to 2024. CiteSpace and VOSviewer software was applied to visualize and analyze publications, countries, institutions, journals, authors, references, and keywords.

Results

A total of 751 articles were collected, the most active countries in this field were the United States and China. The authors with the most publications were Mackinnon, Susan E from the United States, and Xu WD and Gu YD from China. JOURNAL OF HAND SURGERY AMERICAN VOLUME was the journal with the most published. Based on keywords, the current research hotspots primarily revolved around nerve transfer, brachial plexus and reconstruction.

Conclusion

The results of this bibliometric study provide clinical trends and hotspots in the surgical treatment of peripheral nerve injuries of the upper limb over the past 24 years, which may help researchers to identify clinical trends and explore new treatment in the field of peripheral nerve injuries.

Technique and Expected Benefit of Intraoperative Perfusion Imaging of Peripheral Nerves

Peripheral nerve surgery, particularly in cases of nerve compression syndrome (NCS), necessitates a comprehensive evaluation of intraneural blood flow, as localized reductions in nerve perfusion are integral to the etiopathogenesis of such conditions. Although nerve perfusion is currently guided by morphologic characteristics, this assessment is subjective and prone to bias. Intraoperative fluorescence-assisted perfusion imaging with indocyanine green (ICG) is an established tool in flap and lymphatic surgery to objectively assess perfusion intraoperatively. However, only a few unspecific applications of ICG in peripheral nerve surgery have been published so far. In this study, we performed intraoperative perfusion imaging using ICG in 16 consecutive operations within the peripheral nervous system, including microsurgical reconstructions after obstetric brachial plexus injury, decompression for NCS, and vascularized ulnar nerve interposition transfers. Our findings show the utility of ICG in delineating healthy perfusion borders at proximal and distal stump levels after neuroma resection, and we demonstrate a correlation between histological findings and these clinically observed perfusion patterns. In NCS cases, we demonstrate that ICG imaging is effective in highlighting reduced perfusion predecompression and improved perfusion postdecompression. Additionally, ICG proved valuable for assessing perfusion of free vascularized nerve grafts. Intraoperative ICG perfusion imaging is a valuable tool during surgery of the peripheral nervous system, providing insights into the etiopathogenesis of NCS and aiding in the visualization of perfusion. This study underscores the potential of ICG in nerve surgery and its applicability for improving surgical outcomes and advancing our understanding of peripheral nerve pathologies.

The prerequisites and clinical outcomes of ipsilateral C7 nerve root transfer to the upper trunk for adult C5-C6 brachial plexus injuries

PURPOSE

Although ipsilateral C7 nerve transfer is used for the treatment of C5-C6 brachial plexus injuries, accurately evaluating the functional quality of the donor nerve (ipsilateral C7 nerve root) is difficult, especially when the C7 nerve root is slightly injured. The purpose of this study was to determine the indicators to evaluate the quality of the ipsilateral C7 nerve and assess the clinical outcomes of this procedure.

METHODS

This study employed the following three indicators to assess the quality of the ipsilateral C7 nerve: (1) the muscle strength and electrophysiological status of the latissimus dorsi, triceps brachii, and extensor digitorum communis; (2) the sensibility of the radial three digits, especially the index finger; and (3) the intraoperative appearance, feel and electrophysiological status of the ipsilateral C7 nerve root. Transfer of the ipsilateral C7 nerve root to the upper trunk was implemented only when the following three tests were conducted, the criteria were met, and the clinical outcomes were assessed in eight patients with C5-C6 brachial plexus injuries.

RESULTS

Patients were followed-up for an average of 90 ± 42 months. At the final follow-up, all eight patients achieved recovery of elbow flexion, with five and three patients scoring M4 and M3, respectively, according to the Medical Research Council scoring. The shoulder abduction range of motor recovery averaged 86 ± 47° (range, 30°-170°), whereas the shoulder external rotation averaged 51 ± 26° (range, 15°-90°).

CONCLUSION

Ipsilateral C7 nerve transfer is a reliable and effective option for the functional reconstruction of the shoulder and elbow after C5-C6 brachial plexus injuries when the three prerequisites are met.

Functional Outcome following Phrenic Nerve Transfer in Brachial Plexus Injury

Background

Brachial plexus injuries are debilitating injuries resulting in paralyzed shoulder to global paralysis of the upper extremity. Treatment strategies have evolved over the years with nerve transfer forming the mainstay of surgical management. Phrenic nerve provides certain advantages as donor over other options but has been less preferred due to fear of pulmonary complications. In this study, we assess the functional outcomes of phrenic nerve transfer in brachial plexus injuries.

Materials and Methods

A retrospective study was performed on 18 patients operated between 2012 and 2017. The mean duration of injury to surgery was 4.56 months and mean follow-up was for 3.66 years. Phrenic nerve was used as donor to neurotize either biceps and brachialis branch of musculocutaneous nerve or suprascapular nerve. Assessment was done through Waikakul score for elbow flexion and Medical Research Council grading for shoulder abduction. Respiratory function assessment was done through questionnaire.

Results

Twelve (80%) patients recovered grade 3 and above elbow flexion with 6 patients having a positive endurance test according to Waikakul and a "very good" result. In phrenic to suprascapular transfer group (3 patients), all patients had more than grade 3 recovery of shoulder abduction. No patient complained of respiratory problems.

Conclusion

Phrenic nerve can be used as a reliable donor with suitable patient selection with good results in regaining muscle power without any anticipated effects on respiratory function.

Trends and insights review. Nerve procedures in the management of upper limb spasticity

This article reviews the recent advances or nerve-oriented surgical procedures in the treatment of the spastic upper limb. The idea to intervene on the nerve is not recent, but new trends have developed in nerve surgery over the past few years, stimulating experiments and research. Specific surgical procedures involving the nerves have been described at different levels from proximal to distal: at the cervical spinal cord and the dorsal root entry zone (rhizotomy), at the level of the roots (contralateral C7 transfer) or in the peripheral nerve, within the motor trunk (selective neurectomy) or as its branches penetrate the muscles (hyperselective neurectomy). All of these neurosurgical procedures are only effective on spasticity but do not address the other deformities, such as contractures and motor deficit. Additional procedures may have to be planned in conjunction with nerve procedures to optimize outcomes.

Peripheral nerve transfers for dysfunctions in central nervous system injuries: a systematic review

BACKGROUND

The review highlights recent advancements and innovative uses of nerve transfer surgery in treating dysfunctions caused by central nervous system (CNS) injuries, with a particular focus on spinal cord injury (SCI), stroke, traumatic brain injury, and cerebral palsy.

METHODS

A comprehensive literature search was conducted regarding nerve transfer for restoring sensorimotor functions and bladder control following injuries of spinal cord and brain, across PubMed and Web of Science from January 1920 to May 2023. Two independent reviewers undertook article selection, data extraction, and risk of bias assessment with several appraisal tools, including the Cochrane Risk of Bias Tool, the JBI Critical Appraisal Checklist, and SYRCLE's ROB tool. The study protocol has been registered and reported following PRISMA and AMSTAR guidelines.

RESULTS

Nine hundred six articles were retrieved, of which 35 studies were included (20 on SCI and 15 on brain injury), with 371 participants included in the surgery group and 192 in the control group. These articles were mostly low-risk, with methodological concerns in study types, highlighting the complexity and diversity. For SCI, the strength of target muscle increased by 3.13 of Medical Research Council grade, and the residual urine volume reduced by more than 100 ml in 15 of 20 patients. For unilateral brain injury, the Fugl-Myer motor assessment (FMA) improved 15.14-26 score in upper extremity compared to 2.35-26 in the control group. The overall reduction in Modified Ashworth score was 0.76-2 compared to 0-1 in the control group. Range of motion (ROM) increased 18.4-80° in elbow, 20.4-110° in wrist and 18.8-130° in forearm, while ROM changed -4.03°-20° in elbow, -2.08°-10° in wrist, -2.26°-20° in forearm in the control group. The improvement of FMA in lower extremity was 9 score compared to the presurgery.

CONCLUSION

Nerve transfer generally improves sensorimotor functions in paralyzed limbs and bladder control following CNS injury. The technique effectively creates a 'bypass' for signals and facilitates functional recovery by leveraging neural plasticity. It suggested a future of surgery, neurorehabilitation and robotic-assistants converge to improve outcomes for CNS.

Retro Oesophageal Transfer of Contralateral C7 in Birth Brachial Plexus Injury - A Retrospective Study

Background: Presence of available healthy nerve roots on the injured side determines the outcome after nerve reconstruction. Paucity of nerve roots warrants contralateral C7 harvest for optimal results. We aim to study the risks and benefits of retro oesophageal transfer of contralateral C7 root in infants with birth brachial plexus injury. Methods: Study was carried out from 2017 to 2022 in 13 children who have undergone retro oesophageal transfer of contralateral C7 root to affected side. Follow-up period ranged from 8 to 60 months after the surgery. Motor power assessment was done using by active movement scale. Results: Average active movement score for abduction was found to be 6, elbow flexion 5.7, elbow extension 5.8, wrist extension 3, wrist flexion 4, finger flexion 4.8 and finger extension 3.8, respectively. No neurological deficits, limb length anomaly noted in the normal upper limb after contralateral C7 harvest. Conclusions: Retro oesophageal transfer of contralateral C7 is a safe technique in birth brachial plexus injury. The advantage of retro oesophageal transfer is reduction in the length of nerve grafts, thus helping in early neurotisation of distal forearm and hand muscles. The large axonal output from contralateral C7 can be used to reconstruct different nerves without any residual deficits on the normal side. Level of Evidence: Level IV (Therapeutic).

A bibliometric analysis of brachial plexus injury from 1980 to 2022

Background

Brachial plexus injury is a common severe peripheral nerve injury with high disability. At present, the bibliometric analysis of brachial plexus injury is basically unknown.

Methods

This article analyzes the data retrieved to the web of science and uses the R language (version 4.2), Citespace (version 6.1.R3 Advanced), Vosviewer (Lei deng university) to make a scientific map. Specifically, we analyze the main publication countries, institutions, journals where the article is published, and the cooperative relationship between different institutions, the relationship between authors, main research directions in this field, and current research hotspots.

Results

From 1980 to 2022, the total number of publications is 1542. In terms of countries where articles were published, 551 records were published in the United States, accounting for 35% of the total. With 74 articles, Fudan University ranks first in the world in terms of the number of articles issued by the institution, followed by 72 articles from Mayo Clinic. The magazine with the largest number of articles is JOURNAL OF HAND SURGERY-AMERICAN VOLUME, which has published 87 articles in total. GU YD (Gu Yu-Dong) team (Fudan University) and spinner RJ (Robert J Spinner) team (Mayo clinic) are in a leading position in this field. Nerve transfer and nerve reconstruction have been a hot topic of brachial plexus injury. "Spinal nerve root repair and reimplantation of avulsed ventral roots into the spinal cord after brachial plexus injury" has the strongest citation bursts.

Conclusion

Research on brachial plexus injury shows a trend of increasing heat. At present, there is a lack of communication and cooperation between scholars from different countries. Nerve transfer and nerve reconstruction are the current and future research directions in the treatment of brachial plexus injury.

Surgical Treatment in Post-Stroke Spastic Hands: A Systematic Review

Background: For more than two decades, the surgical treatment of post-stroke spastic hands has been displaced by botulinum toxin therapy and is currently underutilized. Objectives: This article aimed to assess the potential of surgery for treating a post-stroke spastic upper extremity through a systematic review of the literature on surgical approaches that are adopted in different profiles of patients and on their outcomes and complications. Methods: Medline PubMed, Web of Science, SCOPUS, and Cochrane Library databases were searched for observational and experimental studies published in English up to November 2022. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluations (GRADE) system. Results: The search retrieved 501 abstracts, and 22 articles were finally selected. The GRADE-assessed quality of evidence was low or very low. The results of the reviewed studies suggest that surgery is a useful, safe, and enduring treatment for post-stroke spastic upper extremities, although most studied patients were candidates for hygienic improvements alone. Patients usually require an individualized combination of techniques. Over the past ten years, interest has grown in procedures that act on the peripheral nerve. Conclusions: Despite the lack of comparative studies on the effectiveness, safety, and cost of the treatments, botulinum toxin has displaced surgery for these patients. Studies to date have found surgery to be an effective and safe approach, but their weak design yields only poor-quality evidence, and clinical trials are warranted to compare these treatment options.

Surgical reconstructions for adult brachial plexus injuries. Part II: Treatments for total arm type

Brachial plexus injuries (BPI) contribute not only to physical dysfunction but also to socioeconomic aspects and psychological disability. Patients with total arm-type BPI will lose not only the shoulder and elbow function but also the hand function, making reconstruction particularly challenging. Reconstructive procedures commonly include nerve repair, grafting, neurotization (nerve transfer), tendon transfer and free functional muscle transfer (FFMT). Although it is difficult to achieve prehensile hand function, most of patients with total arm-type BPI can be treated with satisfied outcomes. In addition to surgical techniques, comprehensive rehabilitation is another important factor for successful outcomes, and efficient communication can help to boost patient morale and eliminate uncertainty.

[Contralateral C7 Nerve Transfer]

Complex brachial plexus injuries with multiple or complete root avulsions make intraplexic reconstruction impossible in some cases. Such cases necessitate the use of extraplexic nerve donors such as the spinal accessory nerve or intercostal nerves. The contralateral C7 root represents a donor with a high axon count and can be used as an axon source in such cases. We summarise current indications, surgical technique and functional results after a contralateral C7 transfer in cases of brachial plexus injury, describing some of our own cases and including a selective literature review.

Dynamic alternations of interhemispheric functional connectivity in brachial plexus avulsion injury patients with nerve transfer: a resting state fMRI study

Brachial plexus avulsion injury (BPAI) is a severe peripheral nerve injury that leads to functional reorganization of the brain. However, the interhemispheric coordination following contralateral cervical 7 nerve transfer remains unclear. In this study, 69 BPAI patients underwent resting-state functional magnetic resonance imaging examination to assess the voxel-mirrored homotopic connectivity (VMHC), which reveals the interhemispheric functional connection. The motor function of the affected upper extremity was measured using the Fugl-Meyer Assessment of Upper Extremity (FMA-UE) scale. The VMHC analysis showed significant differences between the bilateral precentral gyrus, supplementary motor area (SMA), middle frontal gyrus (MFG), and insula. Compared to the preoperative group, the VMHC of the precentral gyrus significantly increased in the postoperative short-term group (PO-ST group) but decreased in the postoperative long-term group (PO-LT group). Additionally, the VMHC of the SMA significantly increased in the PO-LT group. Furthermore, the VMHC of the precentral gyrus in the PO-ST group and the SMA in the PO-LT group were positively correlated with the FMA-UE scores. These findings highlight a positive relationship between motor recovery and increased functional connectivity of precentral gyrus and SMA, which provide possible therapeutic targets for future neuromodulation interventions to improve rehabilitation outcomes for BPAI patients.

Effects of rTMS combined with rPMS on stroke patients with arm paralysis after contralateral seventh cervical nerve transfer: a case-series

OBJECTIVE

We conducted this study to evaluate the effect of rTMS combined with rPMS on stroke patients with arm paralysis after CSCNTS.

METHODS

A case-series of four stroke patients with arm paralysis, ages ranging from 39 to 51 years, that underwent CSCNTS was conducted. Patients were treated with 10 HZ rTMS on the contralesional primary motor cortex combined with 20 HZ rPMS on groups of elbow and wrist muscles for 15 days.

RESULTS

The muscle tone of elbow flexor muscle (EFM), elbow extensor muscle (EEM), wrist flexor muscle (WFM) and flexor digitorum (FD) reduced immediately after operation followed by increasing gradually. After rehabilitation, the muscle tone of EEM and EFM reduced by 14% and 11%, respectively. There was a 13% and 45% change ratio in WFM and FD. The numeric rating scale (mean = 5.75 ± 1.71) was significantly lower (mean = 3.25 ± 1.90, t = 8.66, p = .00). Grip and pinch strength (mean = 23.65 ± 4.91; mean = 4.9 ± 0.59) were significantly higher (mean = 34.63 ± 5.23, t = -61.07, p = .00; mean = 7.1 ± 0.73, t = -13.91, p = .00).

CONCLUSIONS

The rehabilitation of stroke patients with arm paralysis after CSCNTS is a long, complicated process which includes great change of neuropathic pain, muscle tone, and muscle strength. In order to enhance the neural connection between the contralesional hemisphere and the hemiplegic limb, alleviate postoperative complications, as well as accelerate the rehabilitation process, we can consider to use rTMS combined with rPMS.

Donor complications of contralateral C7 nerve transfer in Brachial Plexus Birth Injury: a systematic review

PURPOSE

Contralateral C7 (CC7) nerve transfer is a reconstructive option in the upper limb when there are limited donor options. Promising results have been reported in the adult population but its role in Brachial Plexus Birth Injury (BPBI) is unclear. A major concern with this technique is the potential impact on the contralateral, unaffected limb. Our aim was to review the available literature on the use of this transfer in BPBI, to determine the incidence of short- and long-term deficits at the donor site.

METHODS

The relevant literature was identified from searches of Embase, Ovid Emcare and Ovid MEDLINE, for combinations of terms relating to CC7 nerve transfer and BPBI.

RESULTS

Seventy-five patients were included in this review, from the eight papers that were eligible for inclusion, from a total of 16 papers identified. Patient age ranged from three to 93 months and the shortest follow-up period was six months. Post-operative motor deficits at the donor site included reduced range of shoulder abduction; triceps weakness; and phrenic nerve palsy. All motor deficits recovered within six months. The only sensory deficit reported was reduced sensation in the median nerve distribution which, in all cases, resolved within four weeks. Finally, synchronous donor limb motion and sensation were reported in 46.6% of patients.

CONCLUSION

CC7 nerve transfer in BPBI appears to have few long-term donor limb complications. Sensory and motor deficits are reportedly transient. The impact of synchronous motion and sensation on upper limb function in this patient cohort is not yet known.

Prespinal Versus Conventional Hemicontralateral C7 Nerve Transfer in the Treatment of Total Brachial Plexus Roots Avulsion Injuries: A Retrospective Study With a Minimum Follow-Up Period of 4 Years

PURPOSE

Contralateral C7 (CC7)-to-median nerve transfer has been commonly used to restore hand function in brachial plexus injury. To shorten the nerve graft, the prespinal route was described and achieved direct coaptation when combined with humeral shortening osteotomy. The limb was positioned at 0° shoulder abduction and neutral head position. Given our concern about donor-site morbidity when harvesting the whole CC7 nerve and tension across the neurorrhaphy site after mobilization, we aimed to describe our modified prespinal route and compare its outcomes and complications with the conventional hemi-CC7 transfer.

METHODS

From 2004 to 2014, 39 patients with preganglionic total brachial plexus root avulsion injuries, with a minimum of 4 years of follow-up, were included. Overall, 20 and 19 patients underwent the conventional hemi-CC7-to-median nerve and hemi-CC7-to-lower trunk (LT) transfer through the modified prespinal route, respectively. The modified prespinal route was combined with bilateral clavicle shortening osteotomy to achieve direct coaptation to the LT at 45° shoulder abduction.

RESULTS

The modified prespinal route showed the median period to achieve ≥M3 hand grip assessed in clinical follow-up was shorter (26.5 months vs 45.5 months), and a higher proportion of patients achieved ≥M3 hand grip recovery (63% vs 30%). One patient experienced symptomatic phrenic nerve injury; however, the hemidiaphragm fully recovered after 6 months. The long-term donor-site complication rate was 2.6%, including one sensory abnormality, and no permanent donor-site weakness after hemi-CC7 harvesting was observed.

CONCLUSIONS

The modified prespinal route combined with clavicle osteotomy allowed direct coaptation to the LT and did not require head immobilization. It may allow a higher proportion of patients to achieve ≥M3 hand grip more quickly than conventional hemi-CC7 transfer.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Staged Phrenic Nerve Elongation and Free Functional Gracilis Muscle Transplantation-A Possible Option for Late Reconstruction in Chronic Brachial Plexus Injury

PURPOSE

In patients with late brachial plexus birth injuries, sequelae after acute flaccid myelitis, or chronic adult brachial plexus injury, donor nerves for functioning muscle transplantation are often scarce. We present the results of a potential strategy using the phrenic nerve with staged free gracilis transplantation for upper extremity reanimation in these scenarios.

METHODS

A retrospective review was performed on an institutional database of brachial plexus injury or patients with palsy. All patients underwent a staged reconstruction in which the ipsilateral phrenic nerve was extended by an autogenous nerve graft (PhNG), followed by free-functioning gracilis transplantation (PhNG-gracilis).

RESULTS

Nine patients (6 cases of late brachial plexus birth injuries, 2 of acute flaccid myelitis, and 1 of adult chronic brachial plexus injury) were included in this study. The median follow-up period following the PhNG-gracilis procedure was 27 months (range, 12-72 months). The goals of the staged PhNG and PhNG-gracilis were primarily finger extension or finger flexion. In some patients, the technique was used to improve both elbow and finger function, tunneling the muscle through the flexor compartment of the upper arm and under the mobile wad at the elbow. All patients exhibited improvement of muscle strength, including in finger extension (4 patients) from M0 to M2; finger flexion (3 patients) from M0 to M3; elbow extension (1 patient) from M0 to M2; and elbow flexion (1 patient) from M2 to M4.

CONCLUSIONS

A 2-stage PhNG-gracilis may restore or enhance the residual elbow and/or finger paralysis in chronic brachial plexus injuries. A minimum follow-up period of 3 years is recommended. This technique may remain useful as one of the last reconstructive options to increase power in patients with scarce donor nerves.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Contralateral C7 nerve transfer via the prespinal route in treatment of spastic paralysis of upper limb after cerebral palsy

BACKGROUND

Upper limb spasticity leads to different degrees of disabilities in cerebral palsy, which seriously affects the life of patients. Contralateral C7 nerve transfer has been shown to improve function and reduce spasticity in the affected upper limb with post-stroke hemiplegia. However, reports about the efficacy of this procedure in treating upper limb spasticity caused by hemiplegic cerebral palsy were limited.

CASE DESCRIPTION

We reported two cases (a 23-year-old male and a 18-year-old female) who suffered from hemiplegic cerebral palsy with unilateral sustained upper limb spasticity and underwent contralateral C7 nerve transfer in adulthood. The scores of Fugel-Meyer and ROM of the affected upper limbs were observed before and after surgery. Compared with the preoperative, scores of the latest follow-up both were significantly improved. The muscle tension of the upper limbs decreased, and the symptoms of spasm were alleviated.

CONCLUSIONS

Considering contralateral C7 nerve transfer could effectively relieve spasticity and improve upper limb activity, it can be recommended as one of the reliable methods to manage spasticity and dystonia of upper limbs in patients with hemiplegic cerebral palsy.

A favorable suture method for size-mismatched nerve transfer: comparison with standard perineural suture in an experimental rat study

BACKGROUND

In nerve transfer for peripheral nerve injury, it is sometimes necessary to suture size-mismatched nerves. In 1993, a favorable suture method called the Ochiai suture method for size-mismatched nerve transfer was reported. However, there is currently a lack of substantial evidence beyond the original report. Therefore, this study aimed to verify the advantages of using the Ochiai suture method for size-mismatched nerve transfer.

METHODS

A total of 18 rats were evaluated in this study and randomly divided into two groups. All rats underwent femoral to sciatic nerve transfer. Specifically, group A (n = 10) underwent the Ochiai suture method, while group B (n = 8) underwent the perineural suture method. After 12 weeks postoperatively, we conducted the sciatic functional index (SFI) test, measured muscle wet-weight, and performed histological evaluations. All data were compared between the two groups, with Welch's t test for normally distributed data and Mann-Whitney's U test for non-normally distributed data. Statistical significance was set at p < 0.05.

RESULTS

The mean number of axons was significantly greater in group A than in group B at 5 mm distal to the stump (p = 0.04). Additionally, the average axonal diameter was significantly greater in group A than in group B at 5 mm and 10 mm distal to the stump (p < 0.01 and p < 0.01, respectively). However, the SFI test and measured muscle wet-weight values showed no significant differences between the two groups.

CONCLUSIONS

Our study revealed that the Ochiai suture method for size-mismatched nerve transfer in rats increases the regenerative axon numbers and diameters. These findings suggest that the Ochiai suture method could be a valuable approach for achieving effective motor function restoration in cases of size-mismatched nerve transfer.

Modified contralateral C7 transfer to restore ulnar nerve function without sacrificing median nerve recovery: an experimental study

Contralateral C7 (cC7) transfer is a technique used in patients with total brachial plexus avulsion. An ulnar nerve graft (UNG) is usually used, as intrinsic function is not expected to be restored due to length of reinnervation required. In this study, we attempted to improve intrinsic function recovery by preserving the deep branch of the ulnar nerve (dbUN) and reanimating it with the anterior interosseous nerve (AIN) after cC7 transfer. Fifty-four rats were divided into the following three groups: Group A, traditional cC7 transfer to the median nerve with a UNG; Group B, cC7 transfer preserving and repairing the dbUN with the terminal branch of the AIN; Group C, same as Group B; however, the dbUN was coapted after 1 month with the AIN. At 3, 6 and 9 months postoperatively, the results of electrodiagnostic and histomorphometric examinations of the interosseous muscle were significantly better in Groups B and C, without affecting AIN recovery. In conclusion, the modified cC7 transfer technique can potentially improve intrinsic function recovery without affecting median nerve recovery.

Effect and safety of C7 neurotomy at the intervertebral foramen in patients with chronic poststroke aphasia: a multicentre, randomised, controlled study protocol

INTRODUCTION

Aphasia affects many stroke survivors; therefore, effective treatments are urgently needed. Preliminary clinical findings have suggested an association between contralateral C7-C7 cross nerve transfer and recovery from chronic aphasia. Randomised controlled trials supporting the efficacy of C7 neurotomy (NC7) are lacking. This study will explore the efficacy of NC7 at the intervertebral foramen for improving chronic poststroke aphasia.

METHODS AND ANALYSIS

This study protocol reports a multicentre, randomised, assessor-blinded active-controlled trial. A total of 50 patients with chronic poststroke aphasia for over 1 year and with a aphasia quotient calculated by Western Aphasia Battery Aphasia Quotient (WAB-AQ) score below 93.8 will be recruited. Participants will be randomly assigned to 1 of 2 groups (25 individuals each) to receive NC7 plus intensive speech and language therapy (iSLT), or iSLT alone programme. The primary outcome is the change in Boston Naming Test score from baseline to the first follow-up after NC7 plus 3 weeks of iSLT or iSLT alone. The secondary outcomes include the changes in the WAB-AQ, Communication Activities of Daily Living-3, International Classification of Functioning, Disability and Health (ICF) speech language function, Barthel Index, Stroke Aphasic Depression Questionnaire-hospital version and sensorimotor assessments. The study will also collect functional imaging outcomes of naming and semantic violation tasks through functional MRI and electroencephalogram to evaluate the intervention-induced neuroplasticity.

ETHICS AND DISSEMINATION

This study was approved by the institutional review boards of Huashan Hospital, Fudan University, and all participating institutions. The study findings will be disseminated through peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

ChiCTR2200057180.

Contralateral C7 nerve transfer for severe pediatric brachial plexus injuries: donor site morbidity

BACKGROUND

Pediatric brachial plexus injuries (BPI) can have a devastating impact on upper extremity function. With localized lesions, nerve grafting and transfers are well-described. However, reconstruction of pan-plexus (C5-T1) injuries (PPI) requires donor nerves outside of the brachial plexus. The cross C7 (CC7) nerve transfer extended with sural nerve grafts to the contralateral recipient nerve offers the advantage of supplying robust donor axons. Though controversial in the West, CC7 transfer is routine in many Asian centers. We present a case series of pediatric patients who underwent CC7 transfer for BPI. Our objective was to catalog donor site morbidity incurred by transferring the C7 nerve root.

METHODS

This retrospective study was approved by the Institutional Review Board of our university.

INCLUSION CRITERIA

patients under 18 years old that underwent CC7 nerve transfer for BPI at our health system between 2021 and 2022. A chart review was completed to collect demographic and outcomes data.

RESULTS

Three patients underwent a complete CC7 transfer between 2021 and 2022 for BPI reconstruction. All patients underwent concomitant additional nerve transfers. Post-operative donor site sensory deficits were minimal and transient in all but one patient, who reported mild but persistent paresthesia of the donor side hand with movement of recipient side digits; however, no patients suffered donor site motor deficits (Table 1).

CONCLUSIONS

We conclude that CC7 nerve transfer is a safe surgical option to provide additional donor motor axons for PPI in pediatric patients.

A rat model of modified contralateral C7 transfer permitting ulnar nerve recovery

BACKGROUND

Contralateral C7 transfer (cC7) is an important treatment for total brachial plexus avulsion (TBPA), which sacrifices the recovery of the ulnar nerve (UN). The present study aimed to introduce an animal model of modified cC7 that preserved the deep branch of ulnar nerve (dbUN) and verify its feasibility.

METHODS

Anatomical study: Lengths, diameters, and axon counts of dbUN and anterior interosseous (AIN) branches in six rats were measured. In vivo surgery: 18 rats were divided into three groups. Group A: Traditional cC7. Group B: Modified cC7 finished in one stage. Group C: Modified cC7 and AIN branch anastomosed with dbUN one month after the first stage. Electrophysiological examinations, muscle wet weight, muscle cross-sectional areas, and nerve axon counts were evaluated six months postoperatively.

RESULTS

Anatomical study: The distances from dbUN and AIN branches to the midpoint of the inner and outer epicondyles connection of the humerus, diameters, and axon numbers of dbUN and AIN branches were analyzed, then AIN terminal branch (tbAIN) was anastomosed with dbUN. In vivo surgery: The differences in median nerve fiber counts were not significant. There were more UN axons in group A than in groups B and C. In electrophysiological examinations, muscle wet weight and cross-sectional area of the flexor digitorum profundus showed no significant difference, but the second interosseus cross-sectional areas in groups B and C were significantly larger than in group A.

CONCLUSIONS

This study established an animal model of preserving dbUN in cC7 and verified its feasibility. The possibility of restoring dbUN was established.

Seventh Cervical Nerve (C7) Transection for Spastic Arm Paralysis After Cerebral Injury

BACKGROUND

Spastic limb paralysis because of cerebral injury can cause long-term disability. Its treatment varies from conservative to operative; however, the optimum treatment is yet to be found.

OBJECTIVE

To test the hypothesis that patients with spastic arm paralysis who receive C7 nerve transection to their paralyzed side might have reduction in spasticity, pain, and improvement in arm function.

METHODS

Four patients with spastic hemiparesis that had ceased to improve after 1 year of rehabilitation, having pain and poor function, were included. All 4 patients underwent C7 nerve transection plus rehabilitation. The outcome was assessed at 1, 3, and 6 months by the Fugl-Meyer upper extremity scale for motor recovery, by the Modified Ashworth Scale score for spasticity, and by the visual analogue score for pain. Functional use of the limb was also assessed by performance of activities such as dressing, tying shoe laces, wringing a towel, and operating a mobile phone.

RESULTS

At the end of 6 months, there was a significant improvement in mean Fugl Meyer score, reduction in Modified Ashworth score, and Visual Analogue scale for pain. At the beginning of the study, none of the patients could perform any day-to-day activities; however, at the end of 6 months, 3/4 of the patients could perform at least 1 activity.

CONCLUSION

C7 neurectomy leads to improved motor function, reduction of spasticity and pain, and improvement in function in patients with spastic arm paralysis because of cerebral injury.

Restoration of Grasp after Single-Stage Free Functioning Gracilis Muscle Transfer in Traumatic Adult Pan-Brachial Plexus Injury

BACKGROUND

A variety of approaches have been described to obtain rudimentary grasp after traumatic pan-brachial plexus injury in adults. The aim of this study is to evaluate hand prehension after a gracilis single-stage free functioning muscle transfer.

METHODS

Twenty-seven patients who underwent gracilis single-stage free functioning muscle transfer for elbow flexion and hand prehension after a pan-plexus injury were included. All patients presented with a minimum of 2 years of follow-up. Postoperative finger flexion, elbow flexion strength, preoperative and postoperative Disability of the Arm, Shoulder, and Hand questionnaire scores, secondary hand procedures, complications, and demographic characteristics were analyzed.

RESULTS

Twenty patients (74%) demonstrated active finger pull-through. Only six patients (25%) considered their hand function useful for daily activities. Disability of the Arm, Shoulder, and Hand score improved by 13.1 ± 13.7 ( P < 0.005). All patients were expected to require one secondary procedure (wrist fusion, thumb carpometacarpal fusion, and/or thumb interphalangeal fusion) because no extensor reconstruction was performed. These were performed in 89%, 78%, and 74% of patients, respectively. Four postoperative complications (hematoma, seroma, wound dehiscence, and skin paddle loss) occurred. No flap loss occurred.

CONCLUSIONS

In pan-plexus injuries, the use of a gracilis single-stage free functioning muscle transfer is an alternative to the double free functioning muscle transfer procedure and contralateral C7 transfer, especially for patients who are unable to undergo two to three important operations in a short period of time. Further research and studies are required to improve hand function in these patients.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Long-Term Outcome of 118 Acute Total Brachial Plexus Injury Patients Using Free Vascularized Ulnar Nerve Graft to Innervate the Median Nerve

BACKGROUND

 The restoration of finger movement in total brachial plexus injuries (BPIs) is an ultimate challenge. Pedicled vascularized ulnar nerve graft (VUNG) connecting a proximal root to distal target nerves has shown unpredictable outcomes. We modified this technique by harvesting VUNG as a free flap to reinnervate median nerve (MN). We analyzed the long-term outcomes of these methods.

METHODS

 From years 1998 to 2015, 118 acute total brachial plexus patients received free VUNG to innervate the MN. Patients were followed up at least 5 years after the initial surgery. Donor nerves included the ipsilateral C5 root (25 patients) or contralateral C7 root (CC7 = 93 patients). Recovery of finger and elbow flexion was evaluated with the modified Medical Research Council system. Michigan Hand Score and Quick-DASH were used to represent the patient-reported outcomes.

RESULTS

 For finger flexion, ipsilateral C5 transfer to MN alone yielded similar outcomes to MN + MCN (musculocutaneous nerve), while CC7 had significantly better finger flexion when coapted to MN alone than to MN + MCN. Approximately 75% patients were able to achieve finger flexion with nerve transfer alone. For elbow flexion, best outcome was seen in the ipsilateral C5 to MCN and MN.

CONCLUSION

 In acute total BPI, the priority is to identify the ipsilateral C5 root to innervate MN, with concomitant innervation of MCN to establish the best outcomes for finger and elbow flexion. CC7 is more reliable when used to innervate one target (MN).

LEVEL OF EVIDENCE

 III.

Crossing nerve transfer drives sensory input-dependent plasticity for motor recovery after brain injury

Restoring limb movements after central nervous system injury remains a substantial challenge. Recent studies proved that crossing nerve transfer surgery could rebuild physiological connectivity between the contralesional cortex and the paralyzed arm to compensate for the lost function after brain injury. However, the neural mechanism by which this surgery mediates motor recovery remains still unclear. Here, using a clinical mouse model, we showed that this surgery can restore skilled forelimb function in adult mice with unilateral cortical lesion by inducing cortical remapping and promoting corticospinal tract sprouting. After reestablishing the ipsilateral descending pathway, resecting of the artificially rebuilt peripheral nerve did not affect motor improvements. Furthermore, retaining the sensory afferent, but not the motor efferent, of the transferred nerve was sufficient for inducing brain remapping and facilitating motor restoration. Thus, our results demonstrate that surgically rebuilt sensory input triggers neural plasticity for accelerating motor recovery, which provides an approach for treating central nervous system injuries.

A Cadaver Feasibility Study of Extradural Contralateral C7 Ventral Root Transfer Technique for Treating Upper Extremity Paralysis

STUDY DESIGN

A total of 6 formalin-fixed cadavers were included in the cadaver feasibility study.

OBJECTIVE

The aim was to ascertain the anatomical feasibility of extradural contralateral C7 ventral root transfer technique by cervical posterior.

SUMMARY OF BACKGROUND DATA

Upper limb spastic hemiplegia is a common sequela after stroke. In our previous study, the authors established a method by transferring contralateral C7 dorsal and ventral roots to the corresponding C7 dorsal and ventral roots on the affected side in the cervical posterior.

METHODS

In the present study, six formalin-fixed cadavers were dissected to confirm the anatomical feasibility. Experimental anastomosis in cadavers was conducted. The pertinent lengths of the extradural nerve roots were measured. The tissue structures surrounding regions between the extradural CC7 nerve roots and the vertebral artery were observed. The cervical magnetic resonance imaging scans of 60 adults were used to measure the distance between the donor and recipient nerves.

RESULTS

Experimental anastomosis showed that the distance between the donor and recipient nerves was approximately 1 cm; the short segment of the sural nerve needed bridging. The distance between both exit sites of the exit of the extradural dura mater was 33.57±1.55 mm. The length of the extradural CC7 ventral root was 22.00±0.98 mm. The ventral distance (vd) and the dorsal distance (dd) in males were 23.98±1.72 mm and 30.85±2.22 mm ( P <0.05), while those in females were 23.28±1.51 mm and 30.03±2.16 mm, respectively. C7 vertebral transverse process, ligaments, and other soft tissues were observed between the vertebral artery and the extradural C7 nerve root.

CONCLUSION

Under the premise of less trauma, our study shows that the extradural contralateral C7 ventral root transfer technique, in theory, yields better surgical results, including better recovery of motor function and complete preservation of sensory function.

LEVEL OF EVIDENCE

5.

MRI-Based Optimization Design of the Pre-Spinal Route of Contralateral C7 Nerve Transfer for Spastic Arm Paralysis

Purpose

The prespinal route of contralateral cervical 7 nerve transfer developed by Prof. Wendong Xu helps realize the direct anastomosis of the bilateral cervical 7 nerves. However, 20% of operations still require a nerve graft, which leads to an unfavorable prognosis. This study aims to explore the optimized prespinal route with MRI to further improve the prognosis.

Methods

The current study enrolled 30 patients who suffered from central spastic paralysis of an upper limb and who underwent contralateral cervical 7 nerve transfer via Prof. Xu’s prespinal route through the anterior edge of the contralateral longus colli. MRI images were used to analyze the route length, vertebral artery exposure, and contralateral cervical 7 nerve included angle. Three prespinal routes were virtually designed and analyzed. The selected optimal route was applied to another 50 patients with central spastic paralysis of an upper limb for contralateral cervical 7 nerve transfer.

Results

By the interventions on the 30 patients, the middle and posterior routes were shorter than the anterior route in length, but with no statistical difference between the two routes. Of 30 contralateral vertebral arteries, 26 were located at the posterior medial edge of the longus colli. The average included angles of the anterior, middle, and posterior routes were 108.02 ± 7.89°, 95.51 ± 6.52°, and 72.48 ± 4.65°, respectively. According to these data, the middle route was optimally applied to 50 patients, in whom the rate of nerve transplantation was only 4%, and no serious complications such as vertebral artery or brachial plexus injury occurred.

Conclusion

The low rate of nerve transplantation in 50 patients and the absence of any serious complications in these cases suggests that the middle route is the optimal one.

Cadaveric study to assess the feasibility of S1 neurectomy and contralateral S1 transfer for spastic hemiparesis

Purpose

Acquired brain injury causing spasticity, pain and loss of function is a major cause of disability and lower quality of life. Sacral 1 (S1) neurectomy claims promising outcomes in spastic hemiparesis. This cadaveric study was conducted to study the surgical anatomy, surgical approach and feasibility of S1 neurectomy and contralateral S1 (cS1) transfer.

Methods

This study was conducted over a period of 10 months and 10 cadavers (age 18-60 years, 7 male and 3 female) were included in the study. 2 cadavers underwent endoscopic S1 neurectomy and 8 cadavers underwent open S1 neurectomy. Mean S1 root length and diameter were recorded using Schirmer tear strips and Vernier calliper. Feasibility of transfer was also assessed by measuring the length of donor nerve and distance between distal ends to proximal end of recipient nerve.

Results

Mean thickness of right S1 root was 4.02 ± 1.5 mm and left S1 was 3.89 ± 1.18 mm. Mean length of right S1 root was 24.9 ± 4.56 mm and left S1 was 23.6 ± 2.86 mm. Endoscopically dissected length of S1 was much less as compared to open technique.

Conclusion

S1 neurectomy is simple procedure to reduce spasticity in lower limb without any permanent deficit. It can be done by open as well as with endoscopic approach while for contralateral S1 transfer open approach need to be used.

Reconstruction of hook grip function of the fingers in patients with traumatic brachial plexus injury

We described a reconstruction method for restoring hook grip function of the fingers in patients with total brachial plexus injury. The paralysed latissimus dorsi muscle was transferred to the upper limb as a pedicle flap and sutured to the flexor digitorum profundus tendons. The muscle was then reanimated with two intercostal donor nerves to the thoraco-dorsal nerve. Fourteen young adult patients (mean 23 years, range 17 to 32 years) with traumatic brachial plexus injury who underwent reconstruction using this technique from 2000 to 2019. After mean follow-up of 65 months (range 20 to 170), finger flexion of strength greater than or equal to M3 was achieved in 10 of the 14 patients. The mean weight that could be lifted using a hook grip was 2.6 kg, and that which could be lifted with both hands was 4.1 kg. The intercostal nerve-innervated latissimus dorsi muscle transfer can provide useful hook grip hand function without the need to sacrifice donor vessels or healthy muscles.Level of evidence: IV.

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.

Transfer of a C7 Fascicle for the Pectoralis Major to the Suprascapular Nerve: A 3-Year Follow-Up Patient Series

BACKGROUND

In patients with C5-C6 brachial plexus injury, spinal accessory nerve transfer to the suprascapular nerve is usually performed for the restoration of shoulder abduction. In order to minimize donor deficits, we transferred one fascicle of the ipsilateral C7 root, dedicated to the pectoralis major muscle, to the suprascapular nerve.

METHODS

Ten patients with a mean age of 33 years (range, 19 to 51 years) were operated on at a mean delay of 4 months after their trauma (range, 2 to 7 months). Patients had C5-C6 brachial plexus palsy with avulsed roots on spinal magnetic resonance imaging scan. In addition to the partial C7 transfer, patients sustained nerve transfers to the posterior branch of the axillary nerve and to the motor branches of the musculocutaneous nerve for the biceps and brachialis muscles.

RESULTS

At a mean follow-up of 36 months (range, 29 to 42 months), mean shoulder abduction and external rotation ranges of motion were, respectively, 99 degrees (range, 60 to 120 degrees; p = 0.001) and 58 degrees (range, 0 to 80 degrees; p = 0.001). In nine patients, shoulder abduction strength was graded M4, according the British Medical Research Council grading scale, against 1.6 kg (range, 1 to 2 kg), and was graded M3 in one patient. External rotation strength was graded M4 in nine patients and M3 in one patient. Residual strength of the pectoralis major muscle was graded M4+ in every patient.

CONCLUSIONS

C7 partial transfer to the suprascapular nerve showed satisfactory results at long-term follow-up for active shoulder abduction and external rotation recovery in C5-C6 brachial plexus palsies. This technique replaced spinal accessory nerve transfer in the authors' practice.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Functional outcome of contralateral C7 nerve transfer combined with free functional gracilis transplantation to repair total brachial plexus avulsion: a report of thirty-nine cases

Purpose

Treatment of total brachial plexus avulsion (TBPA) is a challenge in the clinic, especially the restoration of hand function. The current main surgical order is from proximal to distal joints. The purpose of this study was to demonstrate the outcomes of “distal to proximal” surgical method.

Methods

Thirty-nine patients underwent contralateral C7 (CC7) nerve transfer to directly repair the lower trunk (CC7-LT) and phrenic nerve transfer to the suprascapular nerve (PN-SSN) during the first stage, followed by free functional gracilis transplantation (FFGT) for elbow flexion and finger extension. Muscle strength of upper limb, degree of shoulder abduction and elbow flexion, and Semmes–Weinstein monofilament test and static two-point discrimination of the hand were examined according to the modified British Medical Research Council (mBMRC) scoring system.

Results

The results showed that motor recovery reached a level of M3 + or greater in 66.7% of patients for shoulder abduction, 87.2% of patients for elbow flexion, 48.7% of patients for finger extension, and 25.6% of patients for finger flexion. The mean shoulder abduction angle was 45.5° (range 0–90°), and the average elbow flexion angle was 107.2° (range 0–142°), with 2.5 kg average flexion strength (range 0.5–5 kg). In addition, protective sensibility (≥ S2) was found to be achieved in 71.8% of patients.

Conclusion

In reconstruction of TBPA, CC7 transfer combined with free functional gracilis transplantation is an available treatment method. It could help patients regain shoulder joint stability and the function of elbow flexion and finger extension and, more importantly, provide finger sensation and partial finger flexion function. However, the pick-up function was unsatisfied, which needed additional surgery.

Analysis of Results of Contralateral Hemi-C7 Root Used for Restoring Hand Function in Global Birth Brachial Plexus Palsy

PURPOSE

To analyze the outcome of the use of contralateral hemi-C7 for the restoration of hand function in patients with birth brachial plexus global palsy.

METHODS

From 2004 to 2017, 19 infants with Narakas types III and IV birth brachial plexus palsy underwent transfer of contralateral hemi-C7 (posterior division of the contralateral C7 root) to the lower trunk or medial cord on the affected side. All the patients were evaluated for shoulder function using the Gilbert and Mallet scores, elbow flexion using the modified Medical Research Council score for children, and hand function using the Raimondi score. After the surgery, the children were followed-up at 3-month intervals for the first year and 6-month intervals thereafter. Hand function achieving Raimondi scores of 3-5 was considered a useful outcome.

RESULTS

The patients were followed-up for a mean duration of 88 months, with a minimum of 35 and a maximum of 192 months of follow-up. All patients attained a Gilbert score of ≥3, whereas 9 patients attained a score of ≥4. Similarly, all patients attained a minimum aggregate Mallet score of 15, and 9 patients attained a score of ≥20. All patients attained a modified Medical Research Council score of ≥3, used for assessing elbow flexion. Useful hand function was attained in 73% (14/19) of the cases (a Raimondi score of ≥3). There was no clinically recorded deficit on the donor side.

CONCLUSIONS

Contralateral hemi-C7 transfer in infants with brachial plexus root avulsions helped regain useful hand function in 73% (14/19) of the children treated.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Contralateral C7 nerve transfer in the treatment of upper-extremity paralysis: a review of anatomical basis, surgical approaches, and neurobiological mechanisms

The previous three decades have witnessed a prosperity of contralateral C7 nerve (CC7) transfer in the treatment of upper-extremity paralysis induced by both brachial plexus avulsion injury and central hemiplegia. From the initial subcutaneous route to the pre-spinal route and the newly-established post-spinal route, this surgical operation underwent a series of innovations and refinements, with the aim of shortening the regeneration distance and even achieving direct neurorrhaphy. Apart from surgical efforts for better peripheral nerve regeneration, brain involvement in functional improvements after CC7 transfer also stimulated scientific interest. This review summarizes recent advances of CC7 transfer in the treatment of upper-extremity paralysis of both peripheral and central causes, which covers the neuroanatomical basis, the evolution of surgical approach, and central mechanisms. In addition, motor cortex stimulation is discussed as a viable rehabilitation treatment in boosting functional recovery after CC7 transfer. This knowledge will be beneficial towards improving clinical effects of CC7 transfer.

Contralateral C7 Nerve Transfer for Stroke Recovery: New Frontier for Peripheral Nerve Surgery

Ischemic stroke remains a major cause of disability in the United States and worldwide. Following the large-scale implementation of stroke thrombectomy and the optimization of treatment protocols for acute stroke, the reduction in stroke-associated mortality has resulted in an increased proportion of stroke survivors, many of whom have moderate to severe disability. To date, the treatment of subacute and chronic stroke has remained a challenge. Several approaches, involving pharmacological interventions to promote neuroplasticity, brain stimulation strategies and rehabilitative interventions, are currently being explored at different stages of the translational spectrum, yet level 1 evidence is still limited. In a recent landmark study, surgical intervention using contralateral C7 nerve transfer, an approach used to treat brachial plexus injury, was implemented in patients with chronic stroke, demonstrating an added benefit to standard rehabilitation strategies, leading to improved motor performance and reduced spasticity. The procedure involved the transfer of the C7 nerve root and middle trunk from the uninjured extremity to the injured extremity using a short conduit that allows for faster regeneration and innervation of the injured upper extremity via the ipsilateral (contralesional) hemisphere. In this work, we review the rationale for using contralateral C7 nerve transfer in stroke, describe the surgical intervention with associated variations and limitations, and discuss the current evidence for the efficacy of this technique in ischemic stroke research.

Clinical Anatomy of Human Donor C7 Nerve Roots for Surgical Transfer in Patients with Spastic Arm Paralysis

BACKGROUND

Contralateral C7 (CC7) nerve transfer has successfully restored hand function in patients with spastic hemiplegia from chronic central nervous system injuries. However, little is known about the morphology and anatomy of the donor C7 nerve root in patients undergoing this procedure. This study quantified intraoperative measurements of donor C7 nerve roots during CC7 transfer surgery for spastic hemiplegia in patients treated at a high-volume center to describe observed anatomical variations for successful direct anastomosis.

METHODS

A database of images from 21 patients (2 females, 19 males) undergoing CC7 surgery was searched for photographic data that contained a standard ruler measuring donor C7 nerve root length after surgical sectioning and before transfer. Two independent observers analyzed these images and recorded C7 nerve root diameter, length, and branch lengths.

RESULTS

Mean (SD) values of donor C7 nerve measurements were length, 53.5 (8.0) mm; diameter, 5.1 (0.9) mm; branch length following surgical sectioning, 18.3 (6.3) mm. Right-sided donor C7 nerve roots yielded significantly longer branches compared with left-sided donor C7 nerve roots (P = 0.01). Other patient factors such as age, sex, or laterality of brain injury did not influence intraoperative anatomy.

CONCLUSIONS

We report detailed intraoperative measurements of the donor C7 root during CC7 nerve transfer for spastic hemiplegia. These findings describe existing variation in surgical C7 nerve root anatomy in patients undergoing this procedure and may serve as a general reference for the expected donor C7 length in successful direct anastomosis.

The flail elbow: Every surgeon's nightmare

A flail elbow joint has an excessive or abnormal degree of mobility resulting in loss of function. Such a situation can arise from structural damage or loss of neuromuscular control. Structural damage may be in terms of loss of integrity of bony, ligamentous, or both components, and this is commonly caused by trauma, failed arthroplasty, infections - either in the native joint or associated with the above, or inflammatory arthritides. Arm paralysis from any cause may also leads to a loss of muscle control making the elbow flail. The management of the condition varies according to etiology; and concurrent issues like infection and instability need to be addressed in addition to the structural problems. Treatment can be non-surgical with the use of orthotics to support the elbow, and maybe more appropriate in certain circumstances. Surgical treatment can involve fixation, repair or reconstruction. Often the deficiency is not amenable to these methods and arthroplasty has to be considered. The situation becomes more fraught in case of failure of arthroplasty and/or infection, where reconstruction can be challenging. In this review we have considered diverse clinical scenarios that fall under this broad umbrella, with a focus on those encountered commonly in practice.

Direct Repair of the Lower Trunk to Residual Nerve Roots for Restoration of Finger Flexion After Total Brachial Plexus Injury

PURPOSE

Residual nerve root stumps have been used to neurotize the median nerve in an attempt to restore finger flexion function in patients suffering from total brachial plexus injury. However, the results have been unsatisfactory mainly because of the need to use a long nerve graft. The authors have tried to improve the quality of restored finger flexion by direct approximation of available (ruptured) ipsilateral root stumps to the lower trunk (LT). We sought to validate these results using objective outcome measures.

METHODS

This is a study of 27 cases of total posttraumatic brachial plexus palsies. In each case, the neck was explored and ruptured root stumps identified. The LT was mobilized by separating it from the posterior division and the medial cutaneous nerve of the forearm distally. The mobilized LT was then approximated directly to an ipsilateral root stump. The arm was immobilized against the trunk for 2 months. The patients were observed for return of function in the paralyzed upper limb. The presence and strength of finger flexion was measured using the British Medical Council grading.

RESULTS

The follow-up period was 36 to 74 months (average, 56.9 ± 13.7 months). Recovery of active finger flexion was M4 in 10 patients, M3 in 8 patients, and M2 to M0 in 9 patients. Meaningful recovery (M3 or greater) of finger flexion was achieved in 18 of 27 patients.

CONCLUSIONS

The results of active finger flexion can be improved by direct approximation of the LT to an ipsilateral root stump.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Brachial Plexus Injuries - Review of the Anatomy and the Treatment Options

Brachial plexus injuries are still challenging for every surgeon taking part in treating patients with BPI. Injuries of the brachial plexus can be divided into injuries of the upper trunk, extended upper trunk, injuries of the lower trunk and swinging hand where all of the roots are involved in this type of the injury. Brachial plexus can be divided in five anatomical sections from its roots to its terminal branches: roots, trunks, division, cords and terminal branches. Brachial plexus ends up as five terminal branches, responsible for upper limb innervation, musculocutaneous, median nerve, axillary nerve, radial and ulnar nerve. According to the findings from the preoperative investigation combined with clinically found functional deficit, the type of BPI will be confirmed and that is going to determine which surgical procedure, from variety of them (neurolysis, nerve graft, neurotization, arthrodesis, tendon transfer, free muscle transfer, bionic reconstruction) is appropriate for treating the patient.

Aberrant central plasticity underlying synchronous sensory phenomena in brachial plexus injuries after contralateral cervical seventh nerve transfer

BACKGROUNDS

Contralateral cervical seventh (C7) nerve transfer aids motor and sensory recovery in total brachial plexus avulsion injuries (TBPI), but synchronous sensation often persists postoperatively. The mechanism underlying synchronous sensory phenomena remain largely unknown.

OBJECTIVE

To investigate the role of central plasticity in sensory recovery after contralateral C7 nerve transfer.

METHODS

Sixteen right TBPI patients who received contralateral C7 nerve transfer for more than 2 years were included. Sensory evaluations included Semmes-Weinstein monofilament assessment (SWM), synchronous sensation test, and sensory evoked action potential (SNAP) test. Smaller value in the SWM assessment and larger amplitude of SNAP indicates better tactile sensory. Functional magnetic resonance imaging was performed while stimulations delivered to each hand separately in block-design trials for central plasticity analysis.

RESULTS

The SWM value of the injured right hand was increased compared with the healthy left side (difference: 1.76, 95% confidence interval: 1.37-2.15, p < .001), and all 16 patients developed synchronous sensation. In functional magnetic resonance imaging analysis, sensory representative areas of the injured right hand were located in its ipsilateral S1, and 23.4% of this area overlapped with the representative area of the left hand. The ratio of overlap for each patient was significantly correlated with SWM value and SNAP amplitude of the right hand.

CONCLUSION

The tactile sensory functioning of the injured hand was dominated by its ipsilateral SI in long-term observation, and its representative area largely overlapped with the representative area of the intact hand, which possibly reflected a key mechanism of synchronous sensation in patients with TBPI after contralateral C7 transfer.

Contralateral C7 nerve transfer through posterior vertebral approach combined with selective posterior rhizotomy of the affected cervical nerve in the treatment of central upper limb spastic paralysis: A case report

INTRODUCTION

C7 nerve transfer alone can improve upper limb motor function and partial spasticity. Selective posterior rhizotomy (SPR) of the cervical nerve alone can comprehensively improve spasticity but without neuromotor regeneration. We propose a novel possible improvement of contralateral C7 (CC7) nerve transfer through the posterior vertebral approach, which was combined with SPR of the affected cervical nerve.

PATIENT CONCERNS

A 33-year-old male patient presented with cerebral hemorrhage of the left basal ganglia, paralysis of the right limbs, and hypesthesia 8 months earlier. The dysfunction of the affected hand was already present at admission. The patient reported a previous history of hypertension for several years and oral antihypertensive drugs, and blood pressure was controlled within a normal range.

DIAGNOSIS

Central upper limb spastic paralysis. The muscle strength of the right lower limb was grade IV. The Fugl-Meyer score of the right upper limb was 7 points, and the modified Ashworth score was 10.

INTERVENTIONS

The patient underwent CC7 transfer and SPR.

OUTCOMES

The patient successfully underwent CC7 transfer and SPR without complications. On the day after surgery, the left upper limb motions were normal. The Fugl-Meyer score was 9, and the modified Ashworth score of the right upper limb was 2.

CONCLUSIONS

CC7 nerve transfer through the posterior vertebral approach combined with SPR of the affected cervical nerve can possibly improve the surgical outcomes of selected patients with upper limb motor dysfunction and partial spasticity. This method has not been reported in the literature before, and additional studies are necessary.

Why It Is Necessary to Use the Entire Root rather than Partial Root When Doing Contralateral C7 Nerve Transfer: Cortical Plasticity Also Matters besides the Amount of Nerve Fibers

Previous studies suggested that the mode of donor transection is a critical factor affecting the efficacy of the contralateral C7 (CC7) nerve transfer. Nevertheless, the mechanism underlying this phenomenon remains elusive. The aim of this study was to investigate the relationship between the division modes of the CC7 nerve and cortical functional reorganization of Sprague-Dawley rats. We hypothesized that different methods of CC7 nerve transection might induce differences in cortical functional reorganization, thus resulting in differences in surgery efficacy. BDNF, TNF-α/IL-6, and miR-132/134 were selected as indicators of cortical functional reorganization. No significant differences in all these indicators were noted between the entire group and the entire root+posterior division group (P > 0.05). BDNF and miR-132/134 levels in the entire group and the entire root+posterior division group were significantly increased compared with their levels in the posterior group and the blank control group (P < 0.001). In all groups, BDNF, TNF-α/IL-6, and miR-132/134 levels in both hemispheres initially increased and subsequently decreased until week 40. In conclusion, this study provided the evidence of dynamic changes in BDNF, TNF-α/IL-6, and miR-132/134 in the cortex of rats after CC7 nerve transfer using different transecting modes, demonstrating that different CC7 nerve divisions might result in different surgical effects through modulation of cortical reorganization.

Research progress on limb spasmolysis, orthopedics and functional reconstruction of brain-derived paralysis

Brain-derived paralysis is a disease dominated by limb paralysis caused by various brain diseases. The damage of upper motor neurons can lead to spastic paralysis of the limbs in different parts. If it cannot be treated in time and effectively, it will severely affect the motor function and ability of daily living. Treating limb spastic dysfunction in patients with brain-derived paralysis is a global problem. Presently, there are many alternative surgical methods. This article mainly reviews the treatment of limb spastic dysfunction with brain-derived paralysis, focusing on three aspects: limb spasmolysis, orthopedics, and functional reconstruction. Among them, the transposition of the peripheral nerve helps limb function with spastic paralysis and can effectively alleviate limb spasticity.

Transfer of the peroneal component of the sciatic nerve in total brachial plexus lesion: An anatomical feasibility study

Closed brachial plexus lesions (BPLs) are generally associated with a traumatic mechanism of forced traction between the neck and the shoulder-arm complex. For brachial plexus reconstruction different techniques have been proposed with donor motor nerves like intercostal nerves, or the ipsilateral cervical plexus, the phrenic nerve, the contralateral C7 root, and many others. Despite all these surgical possibilities, the overall recovery is generally poor and not satisfactory. The principal drawback is linked to the loss of upper limb proprioception, in a way that dramatically influences even a good motor recovery, so in complete BPLs the sensory loss still represents a debilitating problem. In this anatomical feasibility study, the possibility to transfer the peroneal component of the sciatic nerve as a donor for complete BPLs has been evaluated. This technique would conceptually bring an important motor and sensory contribution to the upper limb using pure motor and sensory branches of the sciatic nerve. Performing immediate tendon transfer for foot drop palsy could significantly decrease the morbidity of the surgical procedure.