[Nerve 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.

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.

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.

Surgery for internal rotation contracture in infancy may obviate the need for brachial plexus nerve reconstruction: early experience

BACKGROUND

Shoulder internal rotation contracture and subluxation in the first year of life has long been recognized in some patients with brachial plexus birth injury (BPBI). Surgical management of shoulder pathology has traditionally been undertaken following nerve reconstruction as necessary. In some patients; however, shoulder pathology may impair or obscure functional neuromuscular recovery of the upper extremity. As a proof of concept, we report a highly selected subset of patients with BPBI in whom shoulder surgery undertaken before one year of age obviated the need for neuroma resection and nerve grafting.

METHODS

A retrospective review was performed of all patients with upper trunk BPBI who underwent shoulder surgery before one year of age from 2015 to 2018. Upper extremity motor function was evaluated with preoperative and postoperative Active Movement Scale scores, Cookie tests, and the requirement for subsequent neuroma resection and nerve grafting.

RESULTS

Fifteen patients with BPBI meeting the inclusion criteria underwent shoulder surgery (including a subscapularis slide and tendon transfers of the teres major and latissimus dorsi muscles) before 1 year of age. Preoperatively, no patients of the appropriate age passed the Cookie test for elbow flexion. Thirteen patients either passed the Cookie test or scored Active Movement Scale score 7 for elbow flexion at or before the last available follow-up undertaken at a median age of 3.4 [1.4, 5.2] years. One of those 13 patients underwent single fascicular distal nerve transfer to improve elbow flexion before subsequently passing the Cookie test. Two patients did not have sufficient follow-up to assess elbow flexion.

CONCLUSION

Although the exact role of shoulder surgery in infancy for BPBI remains to be defined, the findings from this study provide proof of concept that early, targeted surgical treatment of the shoulder may obviate the need for brachial plexus nerve reconstruction in a highly selected group of infants with BPBI.

[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.

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.

Recovery of Shoulder, Elbow, and Forearm Movement After Nerve Reconstruction for Neonatal Brachial Plexus Palsy

BACKGROUND AND OBJECTIVES

There is a relative dearth of published data with respect to recovery of upper extremity movement after nerve reconstruction for neonatal brachial plexus palsy (NBPP). This study aimed to demonstrate long-term recovery of active range of motion (AROM) at the shoulder, elbow, and forearm after nerve reconstruction for NBPP and to compare that with patients managed nonoperatively.

METHODS

We interrogated a prospectively collected database of all patients evaluated for NBPP at a single institution from 2005 to 2020. AROM measurements for shoulder, elbow, and forearm movements were collected at every visit up to 5 years of follow-up and normalized between 0 and 1. We used generalized estimated equations to predict AROM for each movement within local age windows over 5 years and compared the operative and nonoperative cohorts at each age interval.

RESULTS

In total, >13 000 collected datapoints representing 425 conservatively and 99 operatively managed children were included for analysis. At 5 years, absolute recovery of AROM after nerve reconstruction was ∼50% for shoulder abduction and forward flexion, ∼65% for shoulder external rotation, and ∼75% for elbow flexion and forearm supination, with ∼20% loss of elbow extension AROM. Despite more limited AROM on presentation for the operative cohort, at 5 years, there was no significant difference between the groups in AROM for shoulder external rotation, elbow extension, or forearm supination, and, in Narakas grade 1-2 injury, shoulder abduction and forward flexion.

CONCLUSION

We demonstrate recovery of upper extremity AROM after nerve surgery for NBPP. Despite more severe presenting injury, operative patients had similar recovery of AROM when compared with nonoperative patients for shoulder external rotation, elbow extension, forearm supination, and, for Narakas grade 1-2 injury, shoulder abduction and forward flexion.

C5 nerve root palsy (without prior cervical decompression) case series: 9 patients with critical delay to presentation

BACKGROUND

Distinguishing between cervical nerve root and intrinsic shoulder pathology can be a difficult task given the overlapping and often coexisting symptoms.

OBJECTIVE

The objective of this study was to highlight the often-complicated presentation of these symptoms and the subsequent potential for delay in care regarding this subset of patients.

METHODS

A total of 9 patients, managed by one of two different surgeons, were identified with a history of C5 nerve root palsy. A chart review was conducted, and the following information was recorded: presenting complaint, time from symptom onset to diagnosis, time from symptom onset to presentation to a spine surgeon, first specialist seen for symptoms, non-spinal advanced imaging and treatment conducted before diagnosis, preoperative and postoperative exam, time to recovery, and type of surgery.

RESULTS

We observed an average time from onset of symptoms to presentation to a spine surgeon to be 31.6 weeks. These patients' time to full recovery after cervical decompression was 15 weeks.

CONCLUSION

: We observed a critical delay to presentation in this series of patients with C5 nerve palsy. C5 nerve palsy should remain an elemental part of the differential diagnosis in the setting of any shoulder or neck pain presenting with weakness.

Forearm Deformities in Birth Brachial Plexus Palsy - Patient Profile and Management Algorithm

Forearm deformities are often seen in children with severe birth brachial plexus palsy (BBPP). They may be either a supination or a pronation deformity and both hinder normal use of the hand and parents often request for corrective surgery. However, the correction of these deformities can be challenging due to a paucity of options. Also, there is less information in literature on the management of forearm deformities in BBPP compared to the information with regard to nerve surgery or correction of shoulder deformities. This article presents a synopsis of incidence, pathogenesis, clinical presentation and parental concerns related to these deformities. The decision-making considerations, management strategies and outcome expectations are also discussed. Patient selection is very crucial, and the treatment plan must be individualised depending on the disability, parental expectations and existing motor power in the involved limb. Correction of both the deformities have different considerations; however, effective correction of these deformities is immensely satisfactory to the patient/parents in terms of improved function and appearance of the limb. Level of Evidence: Level V (Therapeutic).

A Novel Method of Spinal Accessory Nerve Banking Using Silicone Catheter for Functioning Free Muscle Transfer

In secondary brachial plexus reconstruction, exploring an area that has already been operated on is challenging and time-consuming for a surgeon, especially in centers with a single-team approach. Due to their inertness and lack of adverse effects, silicone Foley catheters were used successfully during the reconstruction of flexor tendons. Based on the concept, we have achieved an acceptable functional outcome by banking the spinal accessory nerve in a silicon catheter for gracilis reanimation, which permits smooth dissection, maintains the length, and shortens the operating time for subsequent reconstruction. Level of Evidence: Level V.

Versatility of the double fascicular transfer in reconstruction of elbow flexion paralysis: Intermediate term follow-up and patient-related outcome measures

OBJECTIVES

The use of fascicle transfers in the reconstruction of traumatic brachial plexus injury is well established, but limited evidence is available regarding their use in atraumatic elbow flexion paralysis. This retrospective case review aimed to verify whether median and ulnar fascicle transfers are similarly effective in atraumatic versus traumatic elbow flexion paralysis when measured using the British Medical Research Council (MRC) scale, Brachial plexus Assessment Tool (BrAT) and Stanmore Percentage of Normal Elbow Assessment (SPONEA) scores at long-term follow-up.

METHODS

All median and ulnar fascicle transfer cases performed at the Queen Elizabeth Hospital Birmingham between August 2007 and November 2018 were reviewed to compare the outcomes of transfers performed for traumatic and atraumatic indications. Data on patient demographics, mechanism and nature of injury, date of injury or symptom onset, date of operation, and other nerve transfers performed were collected. Outcome measures collected included the British MRC scale and two patient-reported outcome measures (PROMs), BrAT and SPONEA.

RESULTS

In total, 34 patients with 45 median and ulnar fascicle transfers were identified. This included 27 traumatic and seven atraumatic brachial plexus insults. Thirty patients had sufficient follow-up to be included in MRC analysis and 17 patients had sufficient follow-up to be included in PROM analysis. No significant differences were found between traumatic and atraumatic subgroups for median MRC, BrAT, or SPONEA scores.

CONCLUSIONS

This study suggests that nerve transfers might be considered effective reconstructive options in atraumatic pathology and provides validation for further research on the subject.

A Randomised Control Trial Comparing the Outcomes of Anterior with Posterior Approach for Transfer of Spinal Accessory Nerve to Suprascapular Nerve in Brachial Plexus Injuries

Background: In brachial plexus surgery, a key focus is restoring shoulder abduction through spinal accessory nerve (SAN) to suprascapular nerve (SSN) transfer using either the anterior or posterior approach. However, no published randomised control trials have directly compared their outcomes to date. Therefore, our study aims to assess motor outcomes for both approaches. Methods: This study comprises two groups of patients. Group A: anterior approach (29 patients), Group B: Posterior approach (29 patients). Patients were allocated to both groups using selective randomisation with the sealed envelope technique. Functional outcome was assessed by grading the muscle power of shoulder abductors using the British Medical Research Council (MRC) scale. Results: Five patients who were operated on by posterior approach had ossified superior transverse suprascapular ligament. In these cases, the approach was changed from posterior to anterior to avoid injury to SSN. Due to this reason, the treatment analysis was done considering the distribution as: Group A: 34, Group B: 24. The mean duration of appearance of first clinical sign of shoulder abduction was 8.16 months in Group A, whereas in Group B, it was 6.85 months, which was significantly earlier (p < 0.05). At the 18-month follow-up, both intention-to-treat analysis and as-treated analysis were performed, and there was no statistical difference in the outcome of shoulder abduction between the approaches for SAN to SSN nerve transfer. Conclusions: Our study found no significant difference in the restoration of shoulder abduction power between both approaches; therefore, either approach can be used for patients presenting early for surgery. Since the appearance of first clinical sign of recovery is earlier in posterior approach, therefore, it can be preferred for cases presenting at a later stage. Also, the choice of approach is guided on a case to case basis depending on clavicular fractures and surgeon preference to the approach. Level of Evidence: Level II (Therapeutic).

Brain plasticity and age after restoring elbow flexion with distal nerve transfers in neonatal brachial plexus palsy and nonneonatal traumatic brachial plexus injury using the plasticity grading scale

OBJECTIVE

Ulnar and/or median nerve fascicle to musculocutaneous nerve (MCN) transfers are used to restore elbow flexion following severe neonatal and nonneonatal brachial plexus injuries (BPIs). Restoring volitional control requires plastic changes in the brain. To date, whether the potential for plasticity is influenced by a patient's age remains unknown.

METHODS

Patients who had presented with a traumatic upper (C5-6 or C5-7) BPI were divided into two groups: neonatal brachial plexus palsies (NBPPs) and nonneonatal traumatic BPIs (NNBPIs). Both groups underwent ulnar or median nerve transfers to the MCN for elbow flexion restoration between January 2002 and July 2020. Only those who attained a British Medical Research Council strength rating of 4 were reviewed. The primary comparison between the two groups was the plasticity grading scale (PGS) score to determine the level of independence of elbow flexion (target) from forearm motor muscle movement (donors). The authors also assessed patient compliance with rehabilitation using a 4-point Rehabilitation Quality Scale. Bivariable and multivariable analyses were used to identify intergroup differences.

RESULTS

In total, 66 patients were analyzed: 22 with NBPP (mean age at surgery 10 months) and 44 with NNBPI (age range at surgery 3-67 years, mean 30.2 years; mean time to surgery 7 months, p < 0.001). All NBPP patients obtained a PGS grade of 4 at the final follow-up versus just 47.7% of NNBPI patients (mean 3.27, p < 0.001). On ordinal regression analysis, after nature of the injury was excluded because of excessive collinearity with age, age was the only significant predictor of plasticity (β = -0.063, p = 0.003). Median rehabilitation compliance scores were not statistically different between the two groups.

CONCLUSIONS

The extent of plastic changes that occur for patients to regain volitional control over elbow flexion after upper arm distal nerve transfers following BPI is influenced by patient age, with complete plastic rewiring more likely in younger patients and virtually ubiquitous in infants. Older patients should be informed that elbow flexion after an ulnar or median nerve fascicle transfer to the MCN might require simultaneous wrist flexion.

Brachial Plexus Birth Injury: A Single-Center Study

Infants can sustain traction injury to brachial plexus nerves during birth, called brachial plexus birth injury (BPBI). While spontaneous recovery is possible, upper extremity weakness can linger. We report our experience at a brachial plexus clinic from a retrospective chart review of infants with BPBI from September 2017 to September 2019. We determined Narakas Classification (NC) and Active Movement Scale (AMS) at predetermined follow-up points. Of 15 patients, 8 presented with NC-I, 5 with NC-II, and 2 with NC-III without Horner's syndrome. By 7 months, 3 had spontaneous recovery, and 4 achieved all and another 4 achieved most AMS5-7 scores. Eleven patients undergoing surgery had little-to-no improvement of shoulder abduction and shoulder external rotation AMS categories by 6 months. Our small sample size prevents us from making definitive conclusions but gave beneficial insight into our clinic barriers to follow-up, data collection, and collaboration with physical and occupational therapy.

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.

Reverse shoulder arthroplasty in obstetric brachial plexus injury: our experience with shoulder motion analysis

BACKGROUND

Obstetric brachial plexus injury (OBPI) is a weakening or paralysis of the upper arm caused by brachial plexus injury followed by a muscle paralysis with severe repercussions on the movement of the shoulder joint following a progressive glenohumeral joint deformity. This case series analyzes the clinical and radiological outcomes of reverse total shoulder arthroplasty (RSA) in OBPI patients with a follow-up of 2 years.

MATERIALS AND METHODS

OBPI patients with secondary end-stage glenohumeral arthritis were enrolled in the study and they were treated with RSA. Patient demographics and clinical outcomes [Range of Motion (ROM), Visual Analog Scale (VAS), Oxford Shoulder Score (OSS)] were evaluated. A novel Shoulder motion analysis was carried out to investigate specific movement patterns of scapulothoracic movements in these patients. This study is a prospective cohort study.

RESULTS

Four Patients (M: F = 1:3) were enrolled in the study, the mean age was 49.3 years (+ 2.75), the mean OSS (Oxford Shoulder Score) decreased from 48.8 (± 2.5) preoperatively to 18.30 (± 2.78), the mean VAS (Visual Analog Scale) decreased from 7.25 (± 0.5) to 1.7 (± 0.3) in the follow up (∆% relative pain reduction:- 76.5%), Shoulder ROM obtained an improvement (p < 0.05) except for abduction and external rotation. The average follow-up time was 26.3 months (+- 4.5). Shoulder motion analysis showed a complete loss of the scapular tilting above 90 degrees of flexion compared to the typical one of standard RSA with a pattern shifted towards scapular retraction (engaging trapezius and rhomboid muscles) to compensate the loss of the posterior tilting.

CONCLUSIONS

RSA in OBPI patients demonstrated a significant improvement of pain symptoms and a moderate improvement in daily activities, anyway with a more appreciable quality of life over time even if the marked hypotrophy especially of the posterior shoulder muscles showed some limits in maintaining suspension of the upper limb and a minor external rotation, with an internal rotation attitude during the movements.

LEVEL OF EVIDENCE

Level IV, Case series.

Posterior Deltoid Function After Transfer of Branch to the Long Head Triceps Brachii of the Radial Nerve to the Anterior Branch of the Axillary Nerve

PURPOSE

The aim of this study was to evaluate the function of the posterior part of the deltoid after nerve transfer of the long head triceps branch of the radial nerve to the anterior branch of the axillary nerve in patients with an upper brachial plexus injury or isolated axillary nerve injury.

METHODS

We retrospectively reviewed 26 patients diagnosed with an upper brachial plexus injury or isolated axillary nerve injury who underwent nerve transfer of the long head triceps muscle branch of the radial nerve to the anterior branch of the axillary nerve in our institute between 2012 and 2017. Data on age, sex, the mechanism of injury, the pattern of injury, and operative treatment were collected from medical records. Preoperative and postoperative clinical examinations, including motor powers of shoulder abduction and extension according to Medical Research Council grading, were evaluated. At a minimum of 2 years after the operation, we evaluated the recovery of the posterior deltoid function using the swallow-tail test.

RESULTS

Twenty-two patients (84.6%) had recovery of posterior deltoid function confirmed by the swallow-tail test. There were 23 patients (88.5%) who achieved at least Medical Research Council grade 4 of shoulder abduction.

CONCLUSIONS

Nerve transfer from the branch to the long head triceps to the anterior branch of the axillary nerve is an effective technique for restoring deltoid function in an upper brachial plexus injury or isolated axillary nerve injury. This technique can provide shoulder abduction and shoulder extension, which are the functions of the posterior deltoid muscle.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

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.

Effect of shorter nerve graft and selective motor branch of recipient nerve on nerve transfer surgery for elbow flexion in patients with brachial plexus injury

OBJECTIVE

The spinal accessory nerve (SAN) is commonly used as a donor nerve for reinnervation of elbow flexors in brachial plexus injury (BPI) reconstruction. However, no study has compared the postoperative outcomes between SAN-to-musculocutaneous nerve (MCN) transfer and SAN-to-nerve to biceps (NTB) transfer. Thus, this study aimed to compare the postoperative time to recovery of elbow flexors between the two groups.

METHODS

A total of 748 patients who underwent surgical treatment for BPI between 1999 and 2017 were retrospectively reviewed. Among them, 233 patients were treated with nerve transfer for elbow flexion. Two techniques were used to harvest the recipient nerve: the standard dissection technique and the proximal dissection technique. The postoperative motor power of elbow flexion was assessed every month for 24 months using the Medical Research Council (MRC) grading system. Survival and Cox regression analyses were used to compare the time to recovery (MRC grade ≥ 3) between the two groups.

RESULTS

Of the 233 patients who underwent nerve transfer surgery, there were 162 patients in the MCN group and 71 patients in the NTB group. At 24 months after surgery, the MCN group had a success rate of 74.1%, and the NTB group had a success rate of 81.7% (p = 0.208). When compared with the MCN group, the NTB group had a significantly shorter median time to recovery (19 months vs 21 months, p = 0.013). Only 11.1% of patients in the MCN group regained MRC grade 4 or 5 motor power 24 months after nerve transfer surgery compared with 39.4% patients in the NTB group (p < 0.001). Cox regression analysis showed that the SAN-to-NTB transfer in combination with the proximal dissection technique was the only significant factor affecting time to recovery (HR 2.33, 95% CI 1.46-3.72; p < 0.001).

CONCLUSIONS

SAN-to-NTB transfer in combination with the proximal dissection technique is the preferred nerve transfer option for restoration of elbow flexion in traumatic pan-plexus palsy.

Lateral Displacement of the Phrenic Nerve in C5 Tumors

BACKGROUND AND OBJECTIVES

Nerve sheath tumors of the brachial plexus frequently distort the local anatomy, increasing the difficulty of safe exposure and resection. However, lateral displacement of the phrenic nerve has not been previously described. The purpose of this study was thus to illustrate the abnormal lateral displacement of the phrenic nerve in 2 cases of patients undergoing brachial plexus tumor resection and provide a possible mechanism for this observation.

METHODS

Two patients underwent surgical resection of clinically progressing C5 schwannomas. During exposure, the phrenic nerve was found to be significantly more superficial and lateral than typical. This structural relationship persisted even after complete resection of the lesion. Both patients did well postoperatively.

RESULTS

The phrenic nerve traverses along the anterolateral aspect of the anterior scalene. However, in these 2 cases of C5 nerve sheath tumors, the phrenic was found to be significantly more lateral and superficial than usual, draping across the medial aspect of the tumor. We believe that the C5-phrenic communicating branch may act as a functional tether that mobilizes the phrenic nerve laterally as the tumor grows. The mass effect on the anterior scalene by the underlying C5 tumor may further contribute to the anterolateral and superficial displacement of the nerve.

CONCLUSION

The phrenic nerve may be seen markedly more laterally and superficially displaced in cases of C5 nerve sheath tumors. It is important for surgeons who operate on lesions of the brachial plexus to be aware of this phenomenon.

Diagnostic Accuracy of Manual Muscle Testing to Identify Nerve Transfer Candidates in Children with Acute Flaccid Myelitis

BACKGROUND

Manual muscle testing is a mainstay of strength assessment despite not having been compared with intraoperative electrical stimulation of peripheral nerves.

METHODS

Intraoperative electrical stimulation served as the reference standard in evaluating predictive accuracy of the Active Movement Scale (AMS) and the Medical Research Council (MRC) scale. Retrospective consecutive sampling of all patients with AFM who underwent exploration or nerve transfer at a pediatric multidisciplinary brachial plexus and peripheral nerve center from March of 2016 to July of 2020 were included. The nonparametric area under the curve (AUC) was calculated. Optimal cutoff score (Youden J ) and diagnostic accuracy values were reported. The AMS and MRC scale were directly compared for predictive superiority.

RESULTS

A total of 181 upper extremity nerves (73 donor nerve candidates and 108 recipient nerve candidates) were tested intraoperatively from 40 children (mean age ± SD, 7.9 ± 4.9 years). The scales performed similarly ( P = 0.953) in classifying suitable donor nerves with satisfactory accuracy (AUC AMS , 71.5%; AUC MRC , 70.7%; optimal cutoff, AMS >5 and MRC >2). The scales performed similarly ( P = 0.688) in classifying suitable recipient nerves with good accuracy (AUC AMS , 92.1%; AUC MRC :, 94.9%; optimal cutoff, AMS ≤3 and MRC ≤1).

CONCLUSIONS

Manual muscle testing is an accurate, noninvasive means of identifying donor and recipient nerves for transfer in children with acute flaccid myelitis. The utility of these results is in minimizing unexpected findings in the operating room and aiding in the development of contingency plans. Further research may extend these findings to test the validity of manual muscle testing as an outcome measure of the success of nerve transfer.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Diagnostic, I.

Shoulder extension impairment with residual neonatal brachial plexus injury

BACKGROUND

Impairment of both shoulder extension and behind-the-back function are common in patients with residual neonatal brachial plexus injury (NBPI), but have scarcely been studied or reported in the literature. Behind-the-back function is classically evaluated using the hand-to-spine task used for the Mallet score. Angular measurements of shoulder extension with residual NBPI have generally been studied utilizing kinematic motion laboratories. To date, no validated clinical examination method for this has been described.

METHODS

Intraobserver and interobserver reliability analyses of 2 shoulder extension angles-passive glenohumeral extension (PGE) and active shoulder extension (ASE)-were performed. Afterwards, a retrospective clinical study was conducted on prospectively collected data on 245 children with residual BPI treated from January 2019 through August 2022. Demographic characteristics, level of palsy, previous surgical procedures, modified Mallet score, and bilateral PGE and ASE data were analyzed.

RESULTS

All inter- and intraobserver agreements were excellent, ranging from 0.82 to 0.86. The median patient age was 8.1 years (3.5-21). Among the 245 children, 57.6% had Erb's palsy, 28.6% extended Erb's palsy, and 13.9% global palsy. One hundred sixty-eight (66%) of the children could not touch their lumbar spine, among whom 26.2% (n = 44) had to swing the arm to reach it. Both the degrees of ASE and PGE achieved correlation significantly with the hand-to-spine score, the ASE strongly (r = 0.705) and the PGE weakly (r = 0.372) (both P < .0001). Significant correlations also were found between lesion level and the hand-to-spine Mallet score (r = -0.339; P < .0001) and ASE (r = -0.299; P < .0001), and between patient age and the PGE (P = .0416, r = -0.130). A statistically significant decrease in PGE and incapacity to reach the spine were found in patients who underwent glenohumeral reduction, shoulder tendon transfer, or humeral osteotomy, relative to those who had microsurgery or no surgery. Receiver operating curves showed that, for both PGE and ASE, the minimum extension angle required to successfully perform the hand-to-spine task was 10°, with sensitivity levels of 69.9 and 82.2, and specificity levels of 69.5 and 87.8 (both P < .0001), respectively.

CONCLUSIONS

Glenohumeral flexion contracture and lost ASE are extremely common in children with residual NBPI. Both the PGE and ASE angles can be measured reliably with a clinical exam, with at least 10° of PGE and ASE necessary to perform the hand-to-spine Mallet task.

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.