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.

Prescriptive and proscriptive lessons for managing shoulder dystocia: a technical and videographical tutorial.

This tutorial of the intrapartum management of shoulder dystocia uses drawings and videos of simulated and actual deliveries to illustrate the biomechanical principles of specialized delivery maneuvers and examine missteps associated with brachial plexus injury. It is intended to complement haptic, mannequin-based simulation training. Demonstrative explication of each maneuver is accompanied by specific examples of what not to do. Positive (prescriptive) instruction prioritizes early use of direct fetal manipulation and stresses the importance of determining the alignment of the fetal shoulders by direct palpation, and that the biacromial width should be manually adjusted to an oblique orientation within the pelvis-before application of traction to the fetal head, the biacromial width is manually adjusted to an oblique orientation within the pelvis. Negative (proscriptive) instructions includes the following: to avoid more than usual and/or laterally directed traction, to use episiotomy only as a means to gain access to the posterior shoulder and arm, and to use a 2-step procedure in which a 60-second hands-off period ("do not do anything") is inserted between the emergence of the head and any initial attempts at downward traction to allow for spontaneous rotation of the fetal shoulders. The tutorial presents a stepwise approach focused on the delivering clinician's tasks while including the role of assistive techniques, including McRoberts, Gaskin, and Sims positioning, suprapubic pressure, and episiotomy. Video footage of actual deliveries involving shoulder dystocia and permanent brachial plexus injury demonstrates ambiguities in making the diagnosis of shoulder dystocia, risks of improper traction and torsion of the head, and overreliance on repeating maneuvers that prove initially unsuccessful.

A critical evaluation of the external and internal maneuvers for resolution of shoulder dystocia.

In the management of shoulder dystocia, it is often recommended to start with external maneuvers, such as the McRoberts maneuver and suprapubic pressure, followed by internal maneuvers including rotation and posterior arm delivery. However, this sequence is not based on scientific evidence of its success rates, the technical simplicity, or the related complication rates. Hence, this review critically evaluates the success rate, technique, and safety of different maneuvers. Retrospective reviews showed that posterior arm delivery has consistently higher success rates (86.1%) than rotational methods (62.4%) and external maneuvers (56.0%). McRoberts maneuver was thought to be a simple method, however, its mechanism is not clear. Furthermore, McRoberts position still requires subsequent traction on the fetal neck, which presents a risk for brachial plexus injury. The 2 internal maneuvers have anatomic rationales with the aim of rotating the shoulders to the wider oblique pelvic dimension or reducing the shoulder width. The techniques are not more sophisticated and requires the accoucher to insert the correct hand (according to fetal face direction) through the more spacious sacro-posterior region and deep enough to reach the fetal chest or posterior forearm. The performance of rotation and posterior arm delivery can also be integrated and performed using the same hand. Retrospective studies may give a biased view that the internal maneuvers are riskier. First, a less severely impacted shoulder dystocia is more likely to have been managed by external maneuvers, subjecting more difficult cases to internal maneuvers. Second, neonatal injuries were not necessarily caused by the internal maneuvers that led to delivery but could have been caused by the preceding unsuccessful external maneuvers. The procedural safety is not primarily related to the nature of the maneuvers, but to how properly these maneuvers are performed. When all these maneuvers have failed, it is important to consider the reasons for failure otherwise repetition of the maneuver cycle is just a random trial and error. If the posterior axilla is just above the pelvic outlet and reachable, posterior axilla traction using either the accoucher fingers or a sling is a feasible alternative. Its mechanism is not just outward traction but also rotation of the shoulders to the wider oblique pelvic dimension. If the posterior axilla is at a higher sacral level, a sling may be formed with the assistance of a long right-angle forceps, otherwise, more invasive methods such as Zavanelli maneuver, abdominal rescue, or symphysiotomy are the last resorts.

Maternal and neonatal complications of shoulder dystocia with a focus on obstetric maneuvers: A case-control study of 1103 deliveries.

INTRODUCTION: Shoulder dystocia is a severe obstetric emergency that can cause substantial neonatal and maternal complications. This study aims to assess the performed obstetric maneuvers and their frequency, success, and association with maternal and neonatal complication rates. MATERIAL AND METHODS: The study population was collected among all deliveries in the Hospital District of Helsinki and Uusimaa between 2006 and 2015 (n = 181 352) by searching for ICD-10 codes for shoulder dystocia, brachial plexus injury and clavicle fracture. Shoulder dystocia cases (n = 537) were identified by reviewing the medical records. Shoulder dystocia cases treated with one or two maneuvers were compared with those treated with at least three. Medical records of a matched control group constituting of 566 parturients without any of the forementioned ICD-10 codes were also scrutinized. RESULTS: Using the four most common obstetric maneuvers (McRoberts maneuver, suprapubic pressure, rotational maneuvers, the delivery of the posterior arm) significantly increased during the study period with individual success rates of 61.0%, 71.9%, 68.1% and 84.8%, respectively. Concurrently, the rate of brachial plexus injury and combined neonatal morbidity significantly declined from 50% to 24.2% (p = 0.02) and from 91.4% to 48.5% (p < 0.001). Approximately 75% of shoulder dystocia cases treated with maneuvers were resolved by the McRoberts maneuver and/or suprapubic pressure, but each of the four most performed maneuvers significantly increased the cumulative success rate individually and statistically (p < 0.001). The rates of brachial plexus injury and combined neonatal morbidity were at their highest (52.9% and 97.8%) when none of the maneuvers were performed and at their lowest when two maneuvers were performed (43.0% and 65.4%). The increasing number (≥3) of maneuvers did not affect the combined maternal or neonatal morbidity or brachial plexus injury but increased the risk for third- or fourth-degree lacerations (odds ratio 2.91, 95% confidence interval 1.17 to 7.24). CONCLUSIONS: The increased use of obstetric maneuvers during the study period was associated with decreasing rates of neonatal complications; conversely, the lack of obstetric maneuvers was associated with the highest rate of neonatal complications. These emphasize the importance of education, maneuver training and urgently performing shoulder dystocia maneuvers according to the international protocol guidelines.

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.

Anatomical damages in the spinal nerve roots and the spinal cord after brachial plexus injury: descriptive study from a cohort of consecutive patients who underwent DREZ-lesioning for pain-practical implications.

BACKGROUND: Systematic descriptions of anatomical damage after brachial plexus injury (BPI) at the intradural level have been scarcely reported in detail. However, considering these damages, not only in the spinal nerve roots but also in the spinal cord itself, is crucial in determining the appropriate surgical approach to restore upper limb function and address refractory pain. Therefore, the authors present a descriptive study focusing on intradural findings observed during microsurgical DREZ-lesioning. METHODS: This study enrolled 19 consecutive patients under the same protocol. Microsurgical observation through exposure of C4 to Th1 medullary segments allowed to describe the lesions in spinal nerve roots, meninges, and spinal cord. Electrical stimulation of the ventral roots checked the muscle responses. RESULTS: Extensive damage was observed among the 114 explored roots (six roots per patient), with only 21 (18.4%) ventral (VR) and 17 (14.9%) dorsal (DR) roots retaining all rootlets intact. Damage distribution varied, with the most frequent impairments in C6 VRs (18 patients) and the least in Th1 VRs (14 patients), while in all the 19 patients for the C6 DRs (the most frequently impaired) and in 14 patients for Th1 DRs (the less impaired). C4 roots were found damaged in 12 patients. Total or partial avulsions affected 63.3% and 69.8% of DRs and VRs, respectively, while 15.8% and 14.0% of the 114 DRs and VRs were atrophic, maintaining muscle responses to stimulation in half of those VRs. Pseudomeningoceles were present in 11 patients but absent in 46% of avulsed roots. Adhesive arachnoiditis was noted in 12 patients, and dorsal horn parenchymal alterations in 10. CONCLUSIONS: Knowledge of intradural lesions post-BPI helps in guiding surgical indications for repair and functional neurosurgery for pain control.

Face presentation at term: incidence, risk factors and influence on maternal and neonatal outcomes.

OBJECTIVES: The incidence, diagnosis, management and outcome of face presentation at term were analysed. METHODS: A retrospective, gestational age-matched case-control study including 27 singletons with face presentation at term was conducted between April 2006 and February 2021. For each case, four women who had the same gestational age and delivered in the same month with vertex position and singletons were selected as the controls (control group, n = 108). Conditional logistic regression was used to assess the risk factors of face presentation. The maternal and neonatal outcomes of the face presentation group were followed up. RESULTS: The incidence of face presentation at term was 0.14‰. After conditional logistic regression, the two factors associated with face presentation were high parity (adjusted odds ratio [aOR] 2.76, 95% CI 1.19-6.39)] and amniotic fluid index > 18 cm (aOR 2.60, 95% CI 1.08-6.27). Among the 27 cases, the diagnosis was made before the onset of labor, during the latent phase of labor, during the active phase of labor, and during the cesarean section in 3.7% (1/27), 40.7% (11/27), 11.1% (3/27) and 44.4% (12/27) of cases, respectively. In one case of cervical dilation with a diameter of 5 cm, we innovatively used a vaginal speculum for rapid diagnosis of face presentation. The rate of cesarean section and postpartum haemorrhage ≥ 500 ml in the face presentation group was higher than that of the control group (88.9% vs. 13.9%, P < 0.001, and 14.8% vs. 2.8%, P = 0.024), but the Apgar scores were similar in both sets of newborns. Among the 27 cases of face presentation, there were three cases of adverse maternal and neonatal outcomes, including one case of neonatal right brachial plexus injury and two cases of severe laceration of the lower segment of the uterus with postpartum haemorrhage ≥ 1000 ml. CONCLUSIONS: Face presentation was rare. Early diagnosis is difficult, and thus easily neglected. High parity and amniotic fluid index > 18 cm are risk factors for face presentation. An early diagnosis and proper management of face presentation could lead to good maternal and neonatal outcomes.

Are Patients With Adult Traumatic Brachial Plexus Injuries Satisfied With Their Appearance?

PURPOSE: Adult traumatic brachial plexus injuries (tBPI) are devastating physically and emotionally. In addition to the physical loss of function and pervasive neuropathic pain, patients describe difficulty with negative self-image and social relationships. Our goal was to gain an initial understanding of body image and satisfaction with appearance among tBPI patients. METHODS: Among 126 patients in a prospective cohort study, 60 completed a brachial plexus injury-specific modification of the Satisfaction with Appearance survey. The survey encompasses three major domains: social discomfort because of the affected limb, interference with relationships because of the affected limb, and appearance of the affected limb. We performed a cross-sectional descriptive analysis to provide an initial understanding of these domains among brachial plexus injury patients. RESULTS: Among all 60 patients, nearly half (27/60, 45%) reported they are satisfied with their overall appearance. The appearance of their affected hand(s) was the body part with which patients expressed the most concern. Patients also reported feeling increasingly uncomfortable among those less familiar to them: 11/60 (18%) were uncomfortable around family, 18/60 (30%) were uncomfortable around friends, and 19/60 (32%) were uncomfortable around strangers. One-quarter (15/60, 25%) of brachial plexus injury patients agreed that their injury interfered with relationships and that their tBPI was unattractive (16/60, 27%) to others. CONCLUSIONS: Almost half of patients who have experienced tBPI endorse dissatisfaction with their appearance, which can subsequently interfere with their personal relationships. Further, tBPI may influence patients' comfort levels in unfamiliar social surroundings and may influence how patients feel they are perceived by others. CLINICAL RELEVANCE: The patient's perception of their affected limb and its influence on their daily social interactions should be recognized by their tBPI care team, noting opportunities for improved counseling.

Pain Interference Prior to and 1 Year After Surgery for Adult Traumatic Brachial Plexus Injury.

PURPOSE: Pain after brachial plexus injury (BPI) can be severely debilitating and is poorly understood. We hypothesized that pain interference (PI) ("the extent to which pain hinders engagement in life") would be predicted by depression, anxiety, severity of pain symptoms, and poorer preoperative muscle function. METHODS: Among patients in a prospective multicenter BPI cohort study, 37 completed Patient-Reported Outcomes Measurement Information System (PROMIS) PI questionnaires before and 1 year after surgery. At both times, participants completed anxiety and depression questionnaires and BPI-specific measures of pain symptoms, physical limitations, and emotional recovery. Surgeon-graded muscle testing, injury severity, age at the time of injury, body mass index, and time from injury to surgery were included. We performed a bivariate analysis of predictors for preoperative and 1-year PROMIS PI followed by multivariable regression modeling using stepwise selection and Bayesian Information Criterion to select covariates. RESULTS: Before surgery, the mean PROMIS PI score was 60.8 ± 11.0, with moderate correlations between PROMIS PI and depression, as well as between PROMIS PI and functional limitations. At 1 year after surgery, the mean PROMIS PI score was 59.7 ± 9.5. There was no difference in preoperative and 1-year PROMIS PI. There were strong correlations between PROMIS PI and pain symptoms, functional limitations, and emotional aspects of recovery at the 1-year follow-up that remained significant in multivariable regression. There were no notable associations between muscle testing and PI. CONCLUSIONS: Pain interference remained substantial and elevated in BPI patients 1 year after surgery. We noted strong associations between PI and pain symptoms, functional limitations, and emotional aspects of recovery. These findings demonstrate the persistence of pain as a feature throughout life after BPI and that its treatment should be considered a priority alongside efforts to improve extremity function. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognosis IV.

Validation of the Root Analysis Score for C5 Viability in Patients With Pan-Brachial Plexus Injury.

PURPOSE: Pan-brachial plexus injury patients present a reconstructive challenge. The root analysis score, developed from parsimonious multivariable modeling of 311 pan-brachial plexus injury patients, determines the probability of having a viable C5 nerve based on four categories: positive C5 Tinel test, intact C5 nerve on computed tomography myelogram, lack of hemidiaphragmatic elevation, and absence of midcervical paraspinal fibrillations. METHODS: Root analysis scores were calculated for a separate cohort of patients with pan-brachial plexus injuries. Scores were validated by the presence or absence of a graftable C5 root, based on supraclavicular exploration and intraoperative electrophysiologic testing. Receiver operating characteristic curve, accuracy, and concordance statistic of the scores were calculated. Patients were divided into three root analysis score cohorts: less than 50 (low), 50-75 (average), and 75-100 points (high) based on dividing the score into quartiles and combining the lowest two. The probability, sensitivity, and specificity of each cohort having an available C5 nerve were based on the intraoperative assessment. RESULTS: Eighty patients (mean age, 33.1 years; 15 women and 65 men) were included. Thirty-one patients (39%) had a viable C5 nerve. The root analysis calculator had an overall accuracy of 82.5%, a receiver operating characteristic of 0.87, and a concordance statistic of 0.87, demonstrating high overall predictive value; 6.5% of patients with a score of less than 50 (94% sensitivity and 43% specificity), 16.1% of patients with a score of 50-75 (94% sensitivity and 67% specificity), and 77.4% of patients with a score of 75-100 (77% sensitivity and 90% specificity) had a graftable C5 nerve. CONCLUSIONS: The root analysis score demonstrated high accuracy and predictive power for a viable C5 nerve. In patients with a score of less than 50, the necessity of supraclavicular root exploration should balance patient factors, presentation timing, and concomitant injuries. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnosis II.

Factors Affecting Outcomes After Free Functional Gracilis Muscle Transfer for Elbow Flexion in Brachial Plexus Injury: A Systematic Review and Meta-Analysis.

PURPOSE: Free functional gracilis transfer (FFGT) is a useful option for reconstruction of elbow flexion following brachial plexus injury presenting late or with poor outcomes from previous nerve surgery. In this systematic review and meta-analysis, we aimed to investigate variables associated with superior outcomes. The efficacy of single versus double FFGT, where the first FFGT is performed to restore elbow flexion, and the choice of donor nerve for neurotization were evaluated. METHODS: A meta-analysis was conducted, including studies that provided postoperative Medical Research Council (MRC) grade for elbow flexion, Disabilities of the Arm, Shoulder, and Hand and visual analog scale scores, quantitative elbow flexion strength, and range of motion. A random effects meta-regression analysis was performed to identify factors associated with improved outcomes. RESULTS: Thirty-seven studies, with 1,607 patients, were analyzed. Single FFGT was reported in 34 studies (n = 1,398), and double FFGT was reported in 10 studies (n = 209). The mean follow-up duration was 37.3 ± 21.1 months. Following single FFGT, 75.4% and 48.9% achieved MRC grades ≥3 and ≥4, respectively. Following double FFGT, 100% achieved an MRC grade ≥3 and 62.7% ≥4. The likelihood of achieving M3 and M4 was significantly greater for double FFGT. Overall, FFGT innervated by the spinal accessory nerve had significantly better recovery of MRC grade ≥3. When comparing only single and double FFGT innervated by spinal accessory nerve, there was no significant difference in recovery of elbow flexion. The meta-regression analysis showed a significant negative correlation between the patient's age and the probability of achieving an MRC grade of ≥3 and 4. CONCLUSIONS: In the overall analysis encompassing all innervating nerves, double FFGT was superior to single FFGT. Subgroup analysis of single and double FFGT innervated by the spinal accessory nerve showed no significant difference. Increasing age was a significant risk factor for poorer outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Impact of tendon transfer on scapulothoracic and glenohumeral motion in children with brachial plexus birth injuries.

BACKGROUND: Tendon transfers are often utilized to improve shoulder external rotation and abduction in children with brachial plexus birth injuries and are designed to improve glenohumeral (GH) joint motion. However, changes in scapulothoracic (ST) and glenohumeral (GH) joint function after tendon transfer are not well defined. The purpose of this study was to quantify changes in GH, ST, and humerothoracic (HT) joint function before and after tendon transfer, and we hypothesized that tendon transfers would reorient the arc of motion into more external rotation and abduction, but not increase GH motion. METHODS: Motion analysis was performed in 15 children (ages 3-16) before and after transfer of teres major and/or latissimus dorsi. Scapulothoracic, GH, and HT joint angles were measured in a neutral, resting position and each of the modified Mallet positions. Joint angular displacements from the neutral position and the total arc of internal-external rotation for each joint were also calculated. Relevant joint angles, joint angular displacements, and internal-external rotation arcs were compared using multivariate analyses of variance with repeated measures and univariate post-hoc analyses. RESULTS: Glenohumeral and HT external rotation were significantly increased in all positions postoperatively. The arc of GH internal-external rotation was unchanged, but oriented in more external rotation after surgery. Only 6 patients gained active external rotation. Glenohumeral and HT internal rotation were significantly decreased after surgery, but ST internal rotation was significantly increased. Two patients had loss of midline function. In the abduction position, GH elevation joint angles were unchanged, but ST and HT elevation increased. DISCUSSION: Only four patients gained active GH external rotation and maintained their internal rotation. Each of those patients underwent isolated tendon transfer without concomitant joint release. Seven patients maintained their preoperative internal rotation, which was attributed to increased ST internal rotation. The other half of patients lost internal rotation and gained external rotation through reorientation of the arc of rotation. Nine patients gained HT elevation, with three attributed to increased ST upward rotation, five attributed to a combination of increased ST upward rotation and increased GH elevation, and one attributed to increased GH abduction contracture. These findings challenge the dogma that teres major/latissimus dorsi tendon transfers augment GH motion and highlight the importance of ST function for outcome determination.

Shoulder external rotation contracture following neonatal brachial plexus injury.

BACKGROUND: Glenohumeral posterior external rotation contractures and scapular winging are frequently overlooked problems in residual neonatal brachial plexus injury (NBPI). Recent attention has emphasized their impact on vital functions such as feeding and hygiene. This study aims to present the epidemiology of posterior glenohumeral contractures in a significant pediatric NBPI population and explore contributing factors. METHODS: We conducted a retrospective analysis of data collected from January 2019 to November 2022, involving a case series of 262 children with residual NBPI. The data included demographics, palsy level, prior surgical history, and the modified Mallet scale. Glenohumeral passive internal rotation in abduction and cross-body adduction angles were measured bilaterally. Subjects were categorized into "Belly-" (Mallet hand-to-belly <3) and "Belly+" (Mallet hand-to-belly ≥3) groups. RESULTS: The median participant age was 7.9 years (range: 3.5-21 years). Extension injury patterns included Erb's palsy (56.5%), extended Erb's palsy (28.6%), and global palsy (14.9%). Contractures exceeding 10°, 20°, and 30° were prevalent in both internal rotation in abduction and cross-body adduction angles. The "Belly-" group (9.5%) demonstrated a significant reduction in both angles compared to the "Belly+" group. Weak correlations were found between internal rotation in abduction (r = 0.390, P < .0001) or cross-body adduction (r = 0.163, P = .0083) angles and Mallet hand-to-abdomen item. Glenohumeral reduction and Hoffer procedures led to a notable decrease in cross-body adduction angle, without affecting "Belly-" prevalence. Global injuries exhibited decreased angles compared to Erb's group. CONCLUSIONS: External rotation glenohumeral contractures are prevalent in residual NBPI, impacting midline access. Surprisingly, the history of glenohumeral procedures or extensive injuries did not increase the likelihood of losing the ability to reach the belly. Receiver operating characteristic analysis suggests specific thresholds for maintaining this ability.

Inactivating Celsr2 promotes motor axon fasciculation and regeneration in mouse and human.

Understanding new modulators of axon regeneration is central to neural repair. Our previous work demonstrated critical roles of atypical cadherin Celsr2 during neural development, including cilia organization, neuron migration and axon navigation. Here, we address its role in axon regeneration. We show that Celsr2 is highly expressed in both mouse and human spinal motor neurons. Celsr2 knockout promotes axon regeneration and fasciculation in mouse cultured spinal explants. Similarly, cultured Celsr2 mutant motor neurons extend longer neurites and larger growth cones, with increased expression of end-binding protein 3 and higher potassium-induced calcium influx. Mice with Celsr2 conditional knockout in spinal motor neurons do not exhibit any behavioural deficits; however, after branchial plexus injury, axon regeneration and functional forelimb locomotor recovery are significantly improved. Similarly, knockdown of CELSR2 using shRNA interference in cultured human spinal motor explants and motor neurons increases axonal fasciculation and growth. In mouse adult spinal cord after root avulsion, in mouse embryonic spinal cords, and in cultured human motor neurons, Celsr2 downregulation is accompanied by increased levels of GTP-bound Rac1 and Cdc42, and of JNK and c-Jun. In conclusion, Celsr2 negatively regulates motor axon regeneration and is a potential target to improve neural repair.

A systematic review of brachial plexus injuries after caesarean birth: challenging delivery?

BACKGROUND: Caesarean section (CS) is widely perceived as protective against obstetric brachial plexus injury (BPI), but few studies acknowledge the factors associated with such injury. The objectives of this study were therefore to aggregate cases of BPI after CS, and to illuminate risk factors for BPI. METHODS: Pubmed Central, EMBASE and MEDLINE databases were searched using free text: ("brachial plexus injury" or "brachial plexus injuries" or "brachial plexus palsy" or "brachial plexus palsies" or "Erb's palsy" or "Erb's palsies" or "brachial plexus birth injury" or "brachial plexus birth palsy") and ("caesarean" or "cesarean" or "Zavanelli" or "cesarian" or "caesarian" or "shoulder dystocia"). Studies with clinical details of BPI after CS were included. Studies were assessed using the National Institutes for Healthy Study Quality Assessment Tool for Case Series, Cohort and Case-Control Studies. MAIN RESULTS: 39 studies were eligible. 299 infants sustained BPI after CS. 53% of cases with BPI after CS had risk factors for likely challenging handling/manipulation of the fetus prior to delivery, in the presence of considerable maternal or fetal concerns, and/or in the presence of poor access due to obesity or adhesions. CONCLUSIONS: In the presence of factors that would predispose to a challenging delivery, it is difficult to justify that BPI could occur due to in-utero, antepartum events alone. Surgeons should exercise care when operating on women with these risk factors.

Cerebral Gray Matter Volume Changes in Patients with Neuropathic Pain from Total Brachial Plexus Injury.

INTRODUCTION: Total brachial plexus injury not only significantly affects the motor and sensory function of the affected upper limbs but also causes further physical and mental damage to patients with long-term intractable pain. Previous studies mainly focused on the surgical treatment, while only a few paid attention to the intractable neuropathic pain caused by this injury. Changes in the volume of gray matter in the brain are thought to be associated with chronic neuropathic pain. METHODS: Voxel-based morphometry analysis was used to compare the difference in cerebral gray matter volume between total brachial plexus injury patients with neuropathic pain and healthy controls. Correlations between pain duration, pain severity, and GM changes were analyzed. RESULTS: The volume of cerebral gray matter in the patient group was decreased significantly in multiple regions, including the parahippocampal gyrus, paracentric lobule, inferior frontal gyrus, auxiliary motor cortex, middle occipital gyrus, right middle temporal gyrus, while it was increased in the insular, pons, middle frontal gyrus, cingulate gyrus, inferior parietal lobule, bilateral thalamus, and globus pallidus. There were no significant correlations between pain duration and rGMV changes, while a positive correlation was observed between pain severity and rGMV changes in one specific region, involving the anterior cingulate cortex. CONCLUSION: Total brachial plexus injury patients with chronic pain have widespread regions of gray matter atrophy and hypertrophy. The only positive correlation was observed between pain severity and rGMV changes in one specific region, suggesting that nociceptive stimuli trigger a variety of nonpain-specific processes, which confirms the multidimensional nature of pain.

Stem cell therapy for traumatic brachial plexus injury.

Stem cell therapy is rapidly evolving, with preclinical studies showing various stem cell types successfully promoting peripheral nerve regeneration. Despite the lack of clinical studies demonstrating efficacy and safety, the number of commercial entities marketing and promoting this treatment direct to patients is also increasing. We describe three adult traumatic brachial plexus injury (BPI) patients who had stem cell therapies prior to consultation in a multidisciplinary brachial plexus clinic. No functional improvement was noted at long-term follow-up despite claims reported by the commercial entities. Considerations and implications of stem cell application in BPI patients are reviewed.

The diagnostic utility of inspiratory-expiratory radiography for the assessment of phrenic nerve palsy associated with brachial plexus injury.

BACKGROUND: The phrenic nerve is commonly injured with trauma to the brachial plexus. Hemi-diaphragmatic paralysis may be well-compensated in healthy individuals at rest but can be associated with persistent exercise intolerance in some patients. This study aims to determine the diagnostic value of inspiratory-expiratory chest radiography compared to intraoperative stimulation of the phrenic nerve for assessing phrenic nerve injury associated with brachial plexus injury. METHODS: Over a 21-year period, the diagnostic utility of three-view inspiratory-expiratory chest radiography for identification of phrenic nerve injury was determined by comparison to intraoperative phrenic nerve stimulation. Multivariate regression analysis was used to identify independent predictors of phrenic nerve injury and having an incorrect radiographic diagnosis. RESULTS: A total of 237 patients with inspiratory-expiratory chest radiography underwent intraoperative testing of phrenic nerve function. Phrenic nerve injury was present in approximately one-fourth of cases. Preoperative chest radiography had a sensitivity of 56%, specificity of 93%, positive predictive negative of 75%, and negative predictive value of 86% for identification of a phrenic nerve palsy. Only C5 avulsion was found to be a predictor of having an incorrect diagnosis of phrenic nerve injury on radiography. CONCLUSION: While inspiratory-expiratory chest radiography has good specificity for detecting phrenic nerve injuries, a high number of false negatives suggest that it should not be relied upon for routine screening of dysfunction after traumatic brachial plexus injury. This is likely multifactorial and relates to variation in diaphragm shape and position, as well as limitations regarding static image interpretation of a dynamic process.

The Effectiveness of Different Nerve Transfers in the Restoration of Elbow Flexion in Adults Following Brachial Plexus Injury: A Systematic Review and Meta-Analysis.

PURPOSE: Restoration of elbow flexion is an important goal in the treatment of patients with traumatic brachial plexus injury. Numerous studies have described various nerve transfers for neurotization of the musculocutaneous nerve (or its motor branches); however, there is uncertainty over the effectiveness of each method. The aim of this study was to summarize the published evidence in adults with traumatic brachial plexus injury. METHODS: Medline, Embase, medRxiv, and bioRxiv were systematically searched from inception to April 12, 2021. We included studies that reported the outcomes of nerve transfers for the restoration of elbow flexion in adults. The primary outcome was elbow flexion of grade 4 (M4) or higher on the British Medical Research Council scale. Data were pooled using random-effects meta-analyses, and heterogeneity was explored using metaregression. Confidence intervals (CIs) were generated to the 95% level. RESULTS: We included 64 articles, which described 13 different nerve transfers. There were 1,335 adults, of whom 813 (61%) had partial and 522 (39%) had pan-plexus injuries. Overall, 75% of the patients with partial brachial plexus injuries achieved ≥M4 (CI, 69%-80%), and the choice of donor nerve was associated with clinically meaningful differences in the outcome. Of the patients with pan-plexus injuries, 45% achieved ≥M4 (CI, 31%-60%), and overall, each month delay from the time of injury to reconstruction reduced the probability of achieving ≥M4 by 7% (CI, 1%-12%). CONCLUSIONS: The choice of donor nerve affects the chance of attaining a British Medical Research Council score of ≥4 in upper-trunk reconstruction. For patients with pan-plexus injuries, delay in neurotization may be detrimental to motor outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Treatment of Complete Brachial Plexus Injuries Using Double Free Muscle Transfer.

PURPOSE: The purpose of this study was to examine the surgical outcomes of double free muscle transfer (DFMT) performed in patients with complete brachial plexus injury (BPI). METHODS: We retrospectively analyzed the outcomes of DFMT for 12 patients with complete BPI who were followed up for more than 2 years after the final muscle transplantation. Their mean age was 29 years (range, 18-41). Three patients underwent contralateral C7 nerve root transfer before the DFMT. The range of motion (ROM) of the shoulder, elbow, and fingers was measured. Patient-reported outcome measures, including Disability of the Shoulder, Arm, and Hand (DASH) scores and visual analog scale (VAS) scores for pain, were also examined. RESULTS: The mean shoulder ROM against gravity was 22° ± 8° in abduction and 33° ± 5° in flexion. Seven patients underwent phrenic nerve (PhN) transfer to the suprascapular nerves, and five exhibited asymptomatic lung impairment on spirography more than 2 years after PhN transfer. The mean elbow ROM against gravity was 111° ± 9° in flexion and -32° ± 7° in extension. All patients obtained elbow flexion >90° against a 0.5-kg weight. All patients obtained touch sensation and two recognized warm and cold sensations in the affected palm. The mean total active motion of the affected fingers was 44° ± 11°. All patients exhibited hook function of the hands. The mean preoperative and postoperative DASH scores were 70.3 ± 13.4 and 51.8 ± 15.9, respectively. The mean pain VAS score was 28 ± 31 at the final follow-up. CONCLUSIONS: Double free muscle transfer provided patients with complete brachial plexus palsy with good elbow flexion and hand hook functions. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.