Optimizing donor fascicle selection in Oberlin's procedure: A retrospective review of anatomical variability using intraoperative neuromonitoring.

BACKGROUND: Transfer of the fascicle carrying the flexor carpi ulnaris (FCU) branch of the ulnar nerve (UN) to the biceps/brachialis muscle branch of the musculocutaneous nerve (Oberlin's procedure), is a mainstay technique for elbow flexion restoration in patients with upper brachial plexus injury. Despite its widespread use, there are few studies regarding the anatomic location of the donor fascicle for Oberlin's procedure. Our report aims to analyze the anatomical variability of this fascicle within the UN, while obtaining quantifiable, objective data with intraoperative neuromonitoring (IONM) for donor fascicle selection. METHODS: We performed a retrospective review of patients at our institution who underwent an Oberlin's procedure from September 2019 to July 2023. We used IONM for donor fascicle selection (greatest FCU muscle and least intrinsic hand muscle activation). We prospectively obtained demographic and electrophysiological data, as well as anatomical location of donor fascicles and post-surgical morbidities. Surgeon's perception of FCU/intrinsic muscle contraction was compared to objective muscle amplitude during IONM. RESULTS: Eight patients were included, with a mean age of 30.5 years and an injury-to-surgery interval of 4 months. Donor fascicle was located anterior in two cases, posterior in two, radial in two and ulnar in two patients. Correlation between surgeon's perception and IONM findings were consistent in six (75%) cases. No long term motor or sensory deficits were registered. CONCLUSIONS: Fascicle anatomy within the UN at the proximal arm is highly variable. The use of IONM can aid in optimizing donor fascicle selection for Oberlin's procedure.

Functional Free Muscle Transfer for Reconstruction of Traumatic Adult Brachial Plexus Injuries.

Traumatic brachial plexus injury is the most common indication for functional free muscle transfer, and elbow flexion recovery is the functional target, followed by shoulder stability and hand reanimation. In this article, we provide a literature review of functional free muscle transfer (FFMT) for adult traumatic brachial plexus injuries and the surgical technical recommendations to achieve the best functional results with FFMT for adult traumatic brachial plexus injuries.

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).

[Nerve Transfers in Children with Non-traumatic Amyoplasia] / Nerventransfers bei Kindern mit nicht traumatischer AmyoplasieNerve Transfers in Children with Non-traumatic Amyoplasia.

BACKGROUND: The treatment of obstetric brachial plexus palsy through primary reconstruction and nerve transfers has been established in the past decades. In the case of non-traumatic diseases that lead to flaccid paralysis and the inability to move the extremities, such as transverse myelitis (TM) or arthrogryposis multiplex congenita (AMC), which can have a wide variety of causes, the focus has been on rehabilitative therapy so far, while surgical interventions have been used to a lesser extent, e. g., in the form of osteotomies or muscle transfers. Our aim is to establish nerve transfers as a surgical option to improve mobility in non-traumatic amyoplasia. PATIENTS: This work presents the needs-adapted treatment of a total of 23 patients (aged 4 months to 64 months, 18 with AMC and 5 with TM) using nerve transfers on the upper extremity. RESULTS: We were able to show that early nerve transfers in the upper extremity enabled the reanimation of muscles in both AMC and TM. CONCLUSION: This work shows that the treatment of non-traumatic amyoplasia in children with selective nerve grafts is a successful method. Nerve transfers allow patients to gain or regain important functions for managing independent everyday life. The surgical methods have been established in the treatment of traumatic nerve injuries. They are well-known and can be carried out safely. We believe that this is an important treatment option for paediatric patients with paralysis associated with TM or AMC, which should also be known to the treating physicians.

[Contralateral C7 Nerve Transfer]. / Der kontralaterale C7 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.

Functional and morphological evaluation of the trapezius muscle after spinal accessory nerve transfer to brachial plexus nerves.

INTRODUCTION: The main innervation of the trapezius muscle is provided by the spinal accessory nerve. Several studies describe the contributions of cervical plexus roots to the trapezius muscle innervation, either directly or through connections with the spinal accessory nerve. There is no adequate understanding of how the trapezius muscle is affected after using the spinal accessory nerve in nerve transfer procedures with the usual technique, preserving at least 1 branch for the upper trapezius. METHODS: We evaluated 20 patients with sequelae of traumatic brachial plexus injury who underwent surgical procedures for brachial plexus repair or free muscle transfer, which included the spinal accessory nerve transfer technique and were followed for a minimum of 1 year. The three portions trapezius muscle were evaluated by physical examination, magnetic resonance imaging (analysis of fatty degeneration) and electromyography. RESULTS: In all evaluation methods, the middle and lower portions of the trapezius muscle showed more significant morphological and/or functional impairment than the upper portion, in most cases. There was a statistically significant difference in all the complementary exams results, between the affected side (with sacrifice of the nerve) versus the normal side, in the middle and lower portions of the trapezius muscle. CONCLUSIONS: Physical examination alone is not sufficient to determine the residual functionality of the trapezius muscle. Magnetic resonance imaging and electromyography are useful tools to assess both morphological involvement of the trapezius muscle and nerve conduction impairment of the trapezius muscle, respectively. The results suggest that the middle and lower portions of the trapezius muscle are affected by previous SAN transfer and should be considered with caution for further muscle transfer procedures.

Rehabilitation protocols in neonates undergoing primary nerve surgery for upper brachial plexus palsy: A scoping review.

INTRODUCTION: Surgical management is recommended in patients with severe neonatal brachial plexus palsy (NBPP) within the first 6 months of age to regain best possible function. Rehabilitation post-surgery remains relatively unexplored. This is a scoping review that explores, which rehabilitation modalities exist and how they vary for different microsurgical approaches in NBPP. MATERIALS AND METHODS: A systematic search was conducted to include articles about upper trunk obstetric brachial plexus nerve microsurgery in pediatric patients that made mention of rehabilitation protocols. The aims of rehabilitation modalities varied and were grouped: "passive" movement to prevent joint contracture or stiffness, "active" or task-oriented movement to improve motor function, or "providing initial motor recovery". Surgical approach was described as either exploration of the brachial plexus (EBP) or nerve transfer without root exploration (NTwoRE). Technique was categorized into transfers and non-transfers. RESULTS: Thirty-six full-text articles were included. Initiation of rehabilitation was 22.26 days post-surgery. Twenty-eight studies were EBP, and six were NTwoRE. Of studies classifiable by aims, nine were "passive", nine were "active", and five were "providing initial motor recovery". Only 27.7% of EBP studies mentioned active therapy, while 75.0% of NTwoRE studies mentioned active therapy. The average age of patients in the EBP procedure category was 7.70 months, and NTwoRE was 17.76 months. Within transfers, the spinal accessory to suprascapular group was more likely to describe an active shoulder exercise therapy, whereas contralateral C7 group was more likely to describe "initial motor recovery", especially through the use of electrostimulation. All articles on electrostimulation recommended 15-20-minute daily treatment. CONCLUSION: Information on rehabilitation is limited post-nerve surgery in NBPP. However, when mentioned, the aims of these therapies vary with respect to surgical approach and technique. The type of therapy to employ may be a multifaceted decision, involving factors such as patient age, initial deformity, and goals of the care team.

Intercostal nerve transfer in management of biceps and triceps co-contraction in brachial plexus birth palsy.

OBJECTIVE: Brachial plexus birth palsy (BPBP) is often caused by traction during birth. In some cases, reinnervation occurs during spontaneous recovery and it causes involuntary co-contraction between antagonistic muscles. When it comes up between the biceps and triceps muscles, smooth active motion of the elbow joint is impaired. We are presenting outcomes of intercostal nerve (ICN) to radial nerve transfer to minimize elbow motion abnormality due to co-contraction. METHODS: We present five cases (two males and three females) of biceps and triceps co-contraction in BPBP patients treated from 2005 to 2018. The mean age at surgery was 9.36 years (range, 4.8-16.4 years). They were treated by ICNs transfer to motor branch of the radial nerve to the triceps muscle. Preoperative electromyography was done in all cases to confirm biceps and triceps co-contraction and to assess the contractile status of both muscles. A 10-s flexion extension test was done pre and postoperatively to assess the efficacy of our procedure. RESULTS: The postop course was uneventful. No donor site morbidity or respiratory complications were recorded in any patient. The mean postoperative follow-up period was 83.9 months (range, 53.6-135.5 months). At the final follow-up, elbow flexion was M4 in the Medical Research Council (MRC) grading scale in all five patients and elbow extension was graded M4 or M4- in all five patients. There was significant increase in the 10 s flexion extension test results delineating the effectiveness of the procedure. CONCLUSIONS: ICNs transfer to motor branch of the radial nerve to the triceps muscle for management of biceps and triceps co-contraction in BPBP is a good option with minimal morbidity and good success rate.

The Evolution of the Reconstructive Strategy for Elbow Flexion for Acute C5, C6 Brachial Plexus Injuries over Two Decades.

BACKGROUND: Over the course of the past two decades, improved outcomes following brachial plexus reconstruction have been attributed to newer nerve transfer techniques. However, key factors aside from surgical techniques have brought improved consistency to elbow flexion techniques in the latter decade. METHODS: One-hundred seventeen patients who underwent brachial plexus reconstruction from 1996 to 2006 were compared with 120 patients from 2007 to 2017. All patients were evaluated preoperatively and postoperatively to assess the recovery time and of elbow flexion strength. RESULTS: In the first decade, nerve reconstruction methods included proximal nerve grafting, intercostal nerve transfer, and Oberlin-I transfer. In the second decade, newer methods such as double fascicular transfer and ipsilateral C7 division transfer to the anterior division of upper trunk were introduced. About 78.6% of the first decade group versus 87.5% of the second decade group were able to reach M3 flexion strength (p = 0.04), with shorter time recovery to reach M3 in the 2nd decade. About 59.8% of the first decade group versus 65.0% of the second decade group were able to reach M4 (p = 0.28), but no significant difference in time of recovery. In both groups, the double fascicular nerve transfer had the highest impact when introduced in the second decade. More precise magnetic resonance imaging (MRI) techniques helped to diagnose the level of injury, the roots involved and evaluate the health of the donor nerves in preparation for intraplexus transfer. CONCLUSION: In addition to modified techniques in nerve transfers, (1) MRI-assisted evaluation and surgical exploration of the roots with (2) more judicious choice of donor nerves for primary nerve transfer were factors that ensured reliable and outcomes in the second decade.

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.

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.

Brain plasticity in neonatal brachial plexus palsies: quantification and comparison with adults' brachial plexus injuries.

PURPOSE: To compare two populations of brachial plexus palsies, one neonatal (NBPP) and the other traumatic (NNBPP) who underwent different nerve transfers, using the plasticity grading scale (PGS) for detecting differences in brain plasticity between both groups. METHODS: To be included, all patients had to have undergone a nerve transfer as the unique procedure to recover one lost function. The primary outcome was the PGS score. We also assessed patient compliance to rehabilitation using the rehabilitation quality scale (RQS). Statistical analysis of all variables was performed. A p ≤ 0.050 set as criterion for statistical significance. RESULTS: A total of 153 NNBPP patients and 35 NBPP babies (with 38 nerve transfers) met the inclusion criteria. The mean age at surgery of the NBPP group was 9 months (SD 5.42, range 4 to 23 months). The mean age of NNBPP patients was 22 years (SD 12 years, range 3 to 69). They were operated around sixth months after the trauma. All transfers performed in NBPP patients had a maximum PGS score of 4. This was not the case for the NNBPP population that reached a PGS score of 4 in approximately 20% of the cases. This difference was statistically significant (p < 0.001). The RQS was not significantly different between groups. CONCLUSION: We found that babies with NBPP have a significantly greater capacity for plastic rewiring than adults with NNBPP. The brain in the very young patient can process the changes induced by the peripheral nerve transfer better than in adults.

Quantifying Patient-Initiated Upper Extremity Movement After Surgical Reconstruction for Adult Pan-Brachial Plexus Injury.

BACKGROUND AND OBJECTIVES: Determining functional recovery in adult patients with traumatic pan-brachial plexus injury (pBPI) is hampered by the fact that most outcome measures are collected in the clinical setting and may not reflect arm use in the real world. This study's objectives were to demonstrate the feasibility of using wearable motion sensor technology to quantify spontaneous arm movement in adult patients with pBPI after surgical reconstruction and report the time and intensity with which the affected arm was used. METHODS: Twenty-nine patients with pBPI who underwent surgical reconstruction at least 2 years prior were included in this study. Study participants wore an accelerometer on bilateral arms for 7 days. The vector time (VT) and magnitude with which each arm moved were collected and divided by the same values collected from the uninjured arm to generate a ratio (VT and vector magnitude [VM], respectively) to quantify differences between the arms. Correlations between VT, VM, and patient demographic and physician-elicited clinical measures were calculated. Patients were enrolled at Chang Gung Memorial Hospital, Linkou Medical Center, Taiwan, and data analysis was performed at the University of Michigan. RESULTS: Twelve patients had pan-avulsion injuries, and 17 patients had C5 rupture with C6-T1 avulsion injuries. All underwent nerve reconstruction with contralateral C7 or ipsilateral C5 nerve roots as donors. At mean 7.3 years after surgery, the mean VT ratio was 0.54 ± 0.13 and the mean VM ratio was 0.30 ± 0.13. Both VT and VM ratios were significantly correlated with patient employment and movements at the elbow and forearm. CONCLUSION: Wearable motion detection technology can capture spontaneous, real-world movements of the arm in patients who have undergone surgical reconstruction for pBPI. Despite severe injuries, these patients are able to use their affected arm 50% of the time and with 30% of the intensity of their unaffected arm, which is positively correlated with return to work after injury. These data support the use of surgical reconstruction for pBPI.

A favourable suture method for size-mismatched nerve transfer: a case series of intercostal-to-musculocutaneous nerve transfer for brachial plexus injury.

We review a nerve suture method for size-mismatched nerve transfers and report a case series involving patients with brachial plexus injury who underwent intercostal-to-musculocutaneous nerve transfer using this method.

Key Considerations for Nerve Transfer Rehabilitation After Surgical Reconstruction for Brachial Plexus and Peripheral Nerve Injuries.

Nerve transfer surgery is commonly used to treat patients with brachial plexus injuries. However, guidelines on postoperative rehabilitation are not clearly established. Nerve transfers require the patient to relearn how to recruit newly innervated muscle(s), which may not occur naturally or intuitively. Supervised therapy is a valuable resource to guide patients through their lengthy recovery (often >12 months) because target muscle strength is both obtained and functionally used in daily life. This article highlights 10 key principles that provide the foundation for rehabilitation following nerve transfer surgery after a brachial plexus injury. Due to the shortcomings of the current evidence base for nerve transfer rehabilitation, we have included our anecdotal experience to augment the existing literature. It is important to have a collaborative surgeon-therapist relationship to communicate regarding operative details, expected timelines for reinnervation, patient needs, and realistic expectations. We provide examples of how to tailor the exercise program to synergistically recruit both the donor and target muscle action, including how to appropriately advance exercises based on the current level of nerve return. We also discuss the role that fatigue plays in denervated muscle and how fatigue may affect the exercise demands placed on the target muscle during specific stages of recovery.

Diagnosis of obstetric brachial plexus injury in a 2-year-old girl using high­frequency ultrasonography.

We describe an unusual case of infant obstetric brachial plexus injury located in the cervical (C)5-C6 brachial plexus nerve, which was preoperatively diagnosed using high-frequency ultrasonography (US) at 2 years of age. The girl was diagnosed with a right clavicular fracture because of shoulder dystocia. She had been showing movement limitations of her entire right upper limb after fracture healing and was then referred to our hospital at 2 years of age. High-frequency US showed that the roots of the right brachial plexus ran continuously, but the diameter of C6 was thinner on the affected side than on the contralateral side (right 0.12 cm vs. left 0.20 cm). A traumatic neuroma had formed at the upper trunk, which was thicker (diameter: right 0.35 cm vs. left 0.23 cm; cross-sectional area: right 0.65 cm2 vs. left 0.31 cm2) at the level of the supraclavicular fossa. Intraoperative findings were consistent with ultrasound findings. Postoperative pathology confirmed brachial plexus traumatic neuroma.

Early Elbow Flexion Contracture Predicts Shoulder Contracture in Infants with Brachial Plexus Birth Injury.

OBJECTIVE: To determine if children who present with an elbow flexion contracture (EFC) from brachial plexus birth injury (BPBI) are more likely to develop shoulder contracture and undergo surgical treatment. STUDY DESIGN: Retrospective review of children <2 years of age with BPBI who presented to a single children's hospital from 1993 to 2020. Age, elbow and shoulder range of motion (ROM), imaging measurements, and surgical treatment and outcome were analyzed. Patients with an EFC of ≥10° were included in the study sample. Data from 2445 clinical evaluations (1190 patients) were assessed. The final study cohort included 72 EFC cases matched with 230 non-EFC controls. Three patients lacked sufficient follow-up data. RESULTS: There were 299 included patients who showed no differences between study and control groups with respect to age, sex, race, ethnicity, or functional score. Patients with EFC had 12° less shoulder range of motion (95% CI, 5°-20°; P < .001) and had 2.5 times the odds of shoulder contracture (OR, 2.5; 95% CI, 1.3-4.7; P = .006). For each additional 5° of EFC, the odds of shoulder contracture increased by 50% (OR, 1.5; 95% CI, 1.2-1.8; P < .001) and odds of shoulder procedure increased by 62% (OR, 1.62; 95% CI, 1.04-2.53; P = .03). Sensitivity of EFC for predicting shoulder contracture was 49% and specificity was 82%. CONCLUSIONS: In patients with BPBI <2 years of age, presence of EFC can be used as a screening tool in identifying shoulder contractures that may otherwise be difficult to assess. Prompt referral should be arranged for evaluation at a BPBI specialty clinic, because delayed presentation risks worsening shoulder contracture and potentially more complicated surgery.

Preliminary Results of Branch Level, Brachial Plexus Peripheral Nerve Stimulation on a Non-Human Primate.

Restoring functional hand control is a priority for those suffering from neurological impairments. Functional electrical stimulation (FES) is commonly applied to assist with rehabilitation. However, FES applied intramuscularly typically results in complex surgeries requiring many implants. This paper presents the preliminary findings from a feasibility study focused on evaluating the potential to access the upper extremity peripheral nerves through a single surgical approach (axillary approach). A single Japanese macaque (macaca fuscata) monkey was used to validate the feasibility of this study. Four of the five peripheral nerves which control the upper extremity were exposed, and had multi-contact epineural cuffs implanted: median, radial, ulnar and musculocutaneous. The axillary nerve was not accessible for epineural cuff placement with the current surgical approach used in this study. Electrical stimuli were used to produce movement contraction patterns of muscles relevant to the innervated peripheral nerves. In addition, to assist in quantifying the outcome, evoked potentials were simultaneously recorded from five extrinsic forearm flexors during median nerve stimulation. This feasibility study demonstrated that the axillary approach enables electrode placement to four of the five peripheral nerves required for upper extremity control through a single skin incision.Clinical relevance- This study demonstrated that the electrode placement to most of the peripheral nerves that control the arm and hand can be done by a single surgical approach: axillary approach.