Changes in Shoulder Rotation Based on Elevation in Children With Brachial Plexus Birth Injury.

PURPOSE: Lack of shoulder external rotation is common in children with brachial plexus birth injuries. Development of glenohumeral (GH) dysplasia is associated with progressive loss of passive external rotation. Some authors recommend measuring external rotation with the arm adducted, whereas others recommend measurement with the arm in 90° of abduction. The purpose of this study was to compare active and passive external rotation and internal rotation measured in adduction versus abduction. METHODS: Fifteen children with brachial plexus birth injuries held their affected arms in maximal external and internal rotation with the arm adducted and the arm at approximately 90° of abduction. Active and passive rotations were measured with three-dimensional motion capture. Scapulothoracic (ST) internal/external rotation and GH internal/external rotation joint angles were calculated and compared using multivariable, one-way repeated measures analyses of variance. RESULTS: There were no significant differences for active or passive ST rotation in external rotation in adduction versus abduction. Glenohumeral external rotation was significantly increased with the arm in abduction compared with adduction both actively and passively. There were no differences in ST rotation in active versus passive conditions, but all GH rotations were significantly greater passively. CONCLUSIONS: Shoulder internal/external rotation in abduction and adduction is not interchangeable. Comprehensive assessment of shoulder external and internal rotation should include both adduction and abduction. CLINICAL RELEVANCE: For children with brachial plexus birth injuries, both active and passive GH external rotations were greater in abduction. Therefore, early GH joint dysplasia may be missed if GH external rotation is measured in abduction. Additionally, consistency in arm position is important for comparison over time. The entire ST rotation capacity was used to perform maximal internal and external rotation, but the entire passive GH range of motion was not actively used. This highlights an area for potential surgical intervention to improve motion.

Long-Term Hand and Shoulder Function in Children following Early Surgical Intervention for a Birth-Related Upper Brachial Plexus Injury.

Purpose To better understand the long-term hand and shoulder outcomes of upper brachial plexus birth injuries. Methods We evaluated shoulder and hand function in 32 patients (13 males; 19 females) with a C5/C6 birth injury history). All patients had undergone primary nerve surgery as infants, and 12 underwent a simultaneous shoulder procedure as they presented with a fixed internal rotation contracture of the shoulder. On average, all patients were evaluated and examined 15 years postoperatively. The shoulder function was evaluated using the Miami Shoulder Scale. Hand function was measured by the 9-hole peg test (9-HPT) and statistical analysis included comparison of 9-HPT time against normative data using the Student's t -test. Results The cohort includes 22 right-hand-dominant and 10 left-hand-dominant patients. Mean age at surgery was 10 months; mean age at follow-up was 15 years ± 2 years 2 months. Cumulative shoulder function was "good" or "excellent" (Miami score) in 23 patients. For 9-HPT, 23 out of 32 patients seen had an involved hand with a significant alteration in function. Conclusion Early nerve surgery in cases of upper brachial plexus birth injuries result in the desired outcome. To ensure timely and targeted therapy for any residual deficits, it is imperative that limitations in hand function among children with an Erb's palsy.

Obstetric factors and neonatal outcomes of depressed skull fractures in newborns.

PURPOSE: To determine the obstetric factors affecting the development of depressed skull fracture in neonates. MATERIALS AND METHODS: This was a retrospectively cohort study on neonates born between July 2016 and August 2021. Neonates diagnosed with depressed skull fractures within one week of birth through X-ray and/or brain ultrasonography were included, and their mothers' obstetric characteristics were reviewed. RESULTS: There were 12 cases in 6791 live births. Five women were over 35 years old. All except two were nulliparous. Five cases were delivered from labor induction and others presented with spontaneous labor. Except for two cases, delivery occurred within an hour after full cervical dilatation. Two cases were assisted by vacuum. None displayed fetal distress signs such as low Apgar scores below 7, meconium staining, and umbilical cord pH under 7.2. All depressed fractures were found in the right parietal area. Three cases resulted in focal hyperechoic lesion in brain ultrasonography and two of them showed small hemorrhage-like lesion in magnetic resonance imaging. All depressed skull fractures improved within 6 months in followed X-rays or ultrasonography. CONCLUSIONS: There was no definitely associated obstetric condition for depressed skull fracture of neonates although nulliparous women were majority of the affected cases.

MINIMIZING TEARING DURING VAGINAL DELIVERY WITH A PERINEAL PROTECTION DEVICE - A RANDOMIZED CONTROLLED TRIAL.

BACKGROUND: There is a growing body of evidence indicating that second degree tears cause both short-, and long-term consequences. Very few preventative measures have been found to reduce the incidence of these tears. OBJECTIVE: To investigate if the use of a perineal protection device during vaginal birth reduces severe perineal tearing (≥grade 2 tear) in primiparous women compared to routine manual perineal support. STUDY DESIGN: A single center randomized controlled trial was performed in Sweden 2019-2021. Primiparous women at term were randomly allocated to the intervention group (n=43) where a perineal protection device was used, or to receive routine care (n=49). Main outcome measurement was grade of perineal tear. Secondary outcomes were vaginal and labial tearing. Continuous data was analyzed with Student's T-test or Mann-Whitney U-test. Dichotomous data were analyzed with Pearson X2 test, Fisher's Exact test, and ordinal logistic regression. RESULTS: Women in the intervention group had a significantly lower risk of sustaining more extensive perineal tearing as compared to the control group. Use of the perineal protection device decreased risk of ≥grade 2 tears, in relation to grade 0-1 tears (OR 0.40 [95% CI 0.17-0.94]). Ordinal logistic regression analyses revealed an OR of 0.36 (0.16-0.81) for one-grade-injury increment, using the perineal protection device vs control group (p=0.013). Number needed to treat using the perineal protection device was 4.3 to avoid one ≥grade 2 tear. Women in the treatment group had less labial tearing (p=0.016). No adverse effects were detected. CONCLUSIONS: Use of the perineal protection device reduced the risk of perineal tearing ≥grade 2 tear by 60% as well as labial tearing.

Long-Term Results of Isolated Latissimus Dorsi to Rotator Cuff Transfer in Brachial Plexus Birth Injury.

Background Brachial plexus birth injury results in deficits in strength and motion, occasionally requiring surgery to restore power to the deficient external rotators of the shoulder in these patients. This is a retrospective analysis of the long-term results of an isolated latissimus dorsi transfer to the rotator cuff in patients with brachial plexus birth injury. Methods This is a retrospective review of prospectively collected data for patients undergoing isolated latissimus dorsi transfer into the infraspinatus in addition to release of the internal rotation contracture of the shoulder with greater than 5 years' follow-up. Preoperative and postoperative shoulder elevation and external rotation were documented. Failure of surgery was defined as a return of the internal rotation contracture and a clinically apparent clarion sign. Results A total of 22 patients satisfied the inclusion criteria: 9 global palsies and 13 upper trunk palsies. The average follow-up was 11 years, ranging from 7.5 to 15.9 years. There was a trend for improved external rotation in the global palsy cohort at final follow-up ( p = 0.084). All nine global palsies maintained adequate external rotation without a clarion sign. Five of the 13 upper trunk palsies failed the latissimus dorsi transfer and subsequently required either teres major transfer and/or rotational osteotomy. In these five failures, the period from initial transfer to failure averaged 6.6 years, ranging from 3.4 to 9.5 years. Conclusion The results of this study indicate that patients with global palsy have sustained long-term improved outcomes with isolated latissimus dorsi transfer while patients with upper trunk palsy have a high rate of failure. Based on these results, we recommend isolated latissimus dorsi transfer for global palsy patients who have isolated infraspinatus weakness. Level of Evidence: Case series - Level IV.

The impact of a soft robotic glove on activity performance and body function for brachial plexus birth injury patients-A longitudinal case series.

BACKGROUND: A brachial plexus birth injury (BPBI) can cause reduced ability to use the arm and hand in daily activities due to reduced grip strength and endurance. A soft robotic glove can increase the number of activities performed and improve activity performance for patients with neurological disease. The use of a soft robotic glove for patients with BPBI has not been studied. PURPOSE: To investigate if a soft robotic glove can improve activity performance and body function for patients with BPBI. STUDY DESIGN: Longitudinal Case Series. METHODS: A convenience sample of patients with BPBI, treated by the Brachial plexus injury service in Umeå, Sweden were studied. Eight patients used a soft robotic glove, (Carbonhand®), at home for three months. Data on activity performance and satisfaction with activity performance, active range of motion and strength were collected at baseline, and at three and four months. A patient evaluation form was filled out at three months, all patients kept a diary for three out of 12 weeks. RESULTS: Six out of eight patients wanted to continue using the device and improved their self-perception of activity performance and satisfaction with the performance due to a more secure grip, compared to when not using the device. All patients had improved maximum strength and endurance in elbow flexion at three months. The device was useful as an assisting device and as a training tool. CONCLUSION: A soft robotic glove (Carbonhand) may improve activity performance and perceived satisfaction and increase the number of activities that a person with BPBI can perform in everyday life. It is possible to increase strength in elbow flexion after using such a device. Due to this limited material, more research is needed.

The Outcome of Spinal Accessory Nerve Transfer to the Musculocutaneous Nerve in Birth Brachial Plexus Palsy.

PURPOSE: Patients with brachial plexus birth injury with limited intraplexal donors require the use of extraplexal donors. Concern regarding the potential for respiratory problems resulting from the harvest of intercostal nerves or the phrenic nerve suggests the need for other options. Transfer of the spinal accessory nerve (SAN) is one option for restoring elbow flexion in adult patients; however, there are few reports of the results of this transfer in brachial plexus birth injury. This study aimed to report the result of SAN transfer to the musculocutaneous nerve (MCN) in brachial plexus birth injury. METHODS: Patients who had undergone SAN to MCN nerve transfer were included in this study. Patients were classified according to Narakas classification. The chart was reviewed for the time for recovery of elbow flexion according to the Active Movement Scale (AMS). RESULTS: Eleven patients underwent SAN to MCN transfers with interpositional sural nerve grafts. Mean birthweight was 4,070 grams (range: 3,300-4,670). Mean time to operation was 6.5 months (range: 4-10). Of the 11 patients, two were of Narakas type 3, whereas the others were of type 4. One patient did not recover elbow flexion and underwent later tendon transfer, whereas the other 10 patients reached AMS grade M6 recovery. The median time for AMS grade M1 elbow flexion recovery was eight months (interquartile range: 6.2-8.8) and for AMS grade M5 was 26 months (interquartile range: 14.2-36.5). CONCLUSIONS: Spinal accessory nerve to MCN transfer with an interposition nerve graft is a viable option for restoring elbow flexion. However, long-term outcomes of this procedure have yet to be fully demonstrated. TYPE OF STUDY/LEVEL OF EVIDENCE: Case series IV.

Mechanical Birth Injuries: A Comprehensive Five-Year Analysis From a Tertiary Care Hospital.

BACKGROUND: Birth injury or birth trauma refers to physical damage or trauma that occurs to a newborn during the birthing process. To ensure continuous care and improve neonatal outcomes, it is crucial to know the incidence, types, relation to the mode of delivery, and their management. METHODOLOGY: This is a retrospective cohort study conducted at Aga Khan University Hospital, Pakistan from January 2018 to December 2022. Neonates aged from birth to 28 days of life identified to sustain any form of mechanical birth injuries were included. Data analysis was done using SPSS version 19 (IBM Corp., Armonk, NY). RESULTS: In the last five years, 51 mechanical birth injuries were found among 27,854 deliveries, which accounts for one in 546 births with an overall prevalence of 0.001%. Out of the total mechanical birth injuries, 12 (23.5%) were noticed in spontaneous vaginal delivery, six (11.8%) had instrumental delivery, and 33 (64.7%) patients had cesarean sections. More birth injuries were noticed in emergency cesarean section as compared to vaginal deliveries. There were 40 babies (78%) with soft tissue injuries, seven (14%) had musculoskeletal injuries/fractures, two (4%) babies had intracranial bleeding, and two (4%) had fractures along with intracranial bleeding. There was no mortality reported among these neonates. CONCLUSION: The overall rate of birth injuries was significantly lower as compared to other low and middle-income countries. Most of the birth injuries were soft tissue injuries in patients with cesarean sections. The rate of birth injury did not show any association with the time of delivery. More frequent obstetric emergency drills would improve complications associated with shoulder dystocia.

Outcomes of glenohumeral dysplasia after brachial plexus birth injury using the Sup-ER orthosis.

We investigated the efficacy of the supination-external rotation ('Sup-ER') orthosis, designed as a non-operative treatment to maintain normal anatomical growth of the shoulder, on the progression of glenohumeral dysplasia in patients with brachial plexus birth injuries. The Sup-ER orthosis was fabricated for 20 infants diagnosed with glenohumeral dysplasia after brachial plexus birth injuries and its success in correcting glenohumeral dysplasia was confirmed by objective calculations of the alpha angle on serial ultrasound findings and improvement in Active Movement Scale scores. Of the 20 patients, 14 had successful resolution of glenohumeral dysplasia, confirmed by shoulder abduction, shoulder flexion, external rotation and supination, Active Movement Scale scores and improving alpha angle measurements. Failure to rectify glenohumeral dysplasia, evidenced by worsening ultrasound findings and Active Movement Scale scores, necessitated a change to operative management in six patients.Level of evidence: IV.

Ethnic background as a risk factor for permanent brachial plexus birth injury: A population-based study.

INTRODUCTION: Brachial plexus birth injury is the most common birth injury causing permanent disability in Finland. This study aimed to assess risk factors of a permanent brachial plexus birth injury and calculate the incidence. MATERIAL AND METHODS: This is a retrospective population-based study including all deliveries between 2006 and 2022 in Southern Finland. The number of children born, obstetric data, and migrant status were gathered from the registries of the Finnish Institute for Health and Welfare, and Statistics Finland. Race of the mothers of children with a permanent brachial plexus birth injury was recorded. The severity of permanent brachial plexus birth injury was assessed using the 3-month Toronto test score. A lower score was indicative of a more severe injury (scored 0-10). RESULTS: One hundred of the 298 428 children born during the 17-year study period sustained a permanent brachial plexus birth injury (0.34 per 1000). Mothers of children with a permanent brachial plexus birth injury had a higher body mass index (29 vs. 24 kg/m2) and their pregnancies were more often complicated by diabetes (28% vs. 12%), shoulder dystocia (58% vs. 0.3%), and/or assisted deliveries (45% vs. 10%) compared with all other mothers (p < 0.001). Thirty two of the 52 725 children born to migrant mothers had a permanent brachial plexus birth injury (0.61 per 1000). The incidence of permanent brachial plexus birth injury was 5.7 times higher among children of Black migrants from Africa (18/11 738, 1.53 per 1000) compared with children of native mothers (0.27 per 1000). Black mothers had a higher body mass index at the start of pregnancy (29 vs. 26 kg/m2, p = 0.02) compared with Caucasians. Children of Black mothers had a more severe injury compared with all others (p = 0.007) with a mean 3-month Toronto test score of 4.2 (range 0.0-6.5, SD ±1.6) vs. 5.6 (range 0.0-9.3, SD ±2.2). CONCLUSIONS: Shoulder dystocia and assisted delivery are the most important risk factors for a permanent brachial plexus birth injury. Black race was associated with a higher rate and a more severe permanent brachial plexus birth injury.

Three-Dimensional Upper Limb Movement Analysis in Children and Adolescents With Brachial Plexus Birth Injury: A Systematic Review.

BACKGROUND: To synthesize the current evidence on clinical use of three-dimensional upper limb movement analysis (3D-ULMA) in children and adolescents with brachial plexus birth injury (BPBI). METHODS: MEDLINE, Embase, and Web of Science were searched for relevant studies up to April 2022. An automatic e-mail alert was installed to ensure no eligible article was missed. Articles evaluating 3D-ULMA in children and adolescents with BPBI were included. Covidence web-based platform was used for blind screening of eligible articles. Twenty-one observational studies with a final sample size of 609, encompassing 493 BPBI cases, met the inclusion criteria. Data were extracted using a custom form to support standardized extraction conforming to the Cochrane Checklist of items. Risk of bias was assessed using the Newcastle-Ottawa Scale, the Strengthening the Reporting of Observational Studies in Epidemiology checklist, and a specifically established quality assessment form for kinematic analysis studies. RESULTS: Study setups differed, including six different types of kinematic devices. Twelve studies used the (modified) Mallet positions for their 3D-ULMA. Throughout the studies, 3D-ULMA was used for various purposes. The Newcastle-Ottawa Scale scored 16 articles with five stars or more, indicating fair to moderate quality. CONCLUSIONS: This systematic review summarizes the different 3D-ULMA kinematic devices, test protocols, and their clinical use for BPBI. The use of 3D-ULMA provides valuable, objective, and quantified data to clinicians with regard to movement strategies; it complements existing clinical scales and can be implemented to evaluate effectiveness of therapy interventions. Implications for future research and clinical practice are discussed.

Advancing glenohumeral dysplasia treatment in brachial plexus birth injury: the end-to-side spinal accessory to suprascapular nerve transfer technique.

PURPOSE: Brachial plexus birth injury (BPBI) is a common injury with the spectrum of disease prognosis ranging from spontaneous recovery to lifelong debilitating disability. A common sequela of BPBI is glenohumeral dysplasia (GHD) which, if not addressed early on, can lead to shoulder dysfunction as the child matures. However, there are no clear criteria for when to employ various surgical procedures for the correction of GHD. METHODS: We describe our approach to correcting GDH in infants with BPBIs using a reverse end-to-side (ETS) transfer from the spinal accessory to the suprascapular nerve. This technique is employed in infants that present with GHD with poor external rotation (ER) function who would not necessitate a complete end-to-end transfer and are still too young for a tendon transfer. In this study, we present our outcomes in seven patients. RESULTS: At presentation, all patients had persistent weakness of the upper trunk and functional limitations of the shoulder. Point-of-care ultrasounds confirmed GHD in each case. Five patients were male, and two patients were female, with a mean age of 3.3 months age (4 days-7 months) at presentation. Surgery was performed on average at 5.8 months of age (3-8.6 months). All seven patients treated with a reverse ETS approach had full recovery of ER according to active movement scores at the latest follow-up. Additionally, ultrasounds at the latest follow-up showed a complete resolution of GHD. CONCLUSION: In infants with BPBI and evidence of GHD with poor ER, end-to-end nerve transfers, which initially downgrade function, or tendon transfers, that are not age-appropriate for the patient, are not recommended. Instead, we report seven successful cases of infants who underwent ETS spinal accessory to suprascapular nerve transfer for the treatment of GHD following BPBI.

Mapping the Landscape of Brachial Plexus Birth Injury Research: A Comprehensive Bibliometric Study.

Brachial plexus birth injury (BPBI) is a relatively common condition that poses a significant challenge to children who endure functional impairments later on. This comprehensive bibliometric analysis sought to quantitatively evaluate the existing literature on BPBI, shedding light on authorship, collaboration, publication trends, and keyword analysis to both inform the medical community and foster future research growth. A thorough search of the Web of Science database yielded 712 relevant documents published between 1986 and 2022. The analysis utilized Biblioshiny (K-Synth Srl, Naples, Italy) for bibliometric data, alongside VOSviewer (Centre for Science and Technology Studies, Leiden University, The Netherlands) and TextRazor (TextRazor Ltd., London, UK) for keyword categorization. The literature had an average annual growth rate of 7.94%, with an average document age of 12 years. Collaborative efforts demonstrated 9.6% international co-authorship, with the United States prominently leading global collaborations. Top producing authors included Yang, Kozin, and Clarke, while the most cited authors were Clarke, Waters, and Curtis. Journals such as the Journal of Pediatric Orthopedics and Plastic and Reconstructive Surgery emerged as key contributors to the literature. Keyword analysis illuminated prevalent categories like "society" and "health," underscoring the multifaceted nature of BPBI research. The findings from this bibliometric analysis highlight the dynamic and collaborative landscape of BPBI research, emphasizing the pressing need for continued contributions to address existing gaps in knowledge, enhance global collaboration, and advance the understanding and treatment of this complex condition. Beyond quantitative metrics, this study holds particular significance in its role as a compass for researchers, practitioners, and policymakers invested in BPBI. By offering insights into influential authors, institutions, and emerging trends, this analysis serves as a valuable resource, guiding future research endeavors, fostering interdisciplinary collaboration, and ultimately contributing to improved outcomes for individuals affected by BPBI. The importance of this study lies not only in its informative content but also in its potential to catalyze a collective effort toward refining treatment modalities, promoting preventative measures, and enhancing the overall quality of care for those navigating the challenges of BPBI.

Brachial plexus birth injury: advances and controversies.

While there is considerable spontaneous recovery in most cases of brachial plexus birth injury, many children are left with significant problems that may lead to lifelong functional limitations, loss of work and social isolation. Detailed treatment with the right strategy can provide very valuable improvement in function. Over the past few years, the clinical approach to brachial plexus birth palsy has entered a new era in both diagnostic and surgical treatment methods. This article reviews four areas of management, the role of imaging in defining the severity of the injury, the optimal timing of for nerve exploration and reconstruction in appropriate cases, the advantages and potential complications of nerve transfers, and the role of physiotherapy. Available evidence is considered. Although it is difficult to make clear and precise inferences on a subject where there are many variables and considerable uncertainties, some currently accepted views will be summarized.Level of evidence: V.

Prevalence and predictors of elbow flexion contractures during early childhood following brachial plexus birth injury.

BACKGROUND: Elbow flexion contracture development in school-age children with a brachial plexus birth injury (BPBI) is common. Reports indicate onset between 2 and 4 years; however, little is known about early childhood prevalence, development, and trajectory of these contractures. PURPOSE: To determine the prevalence and predictors of BPBI elbow flexion contractures during early childhood. STUDY DESIGN: A retrospective cross-sectional study. METHODS: Demographic, diagnostic, treatment, and elbow contracture data were collected for children with a BPBI <4 years between 2015 and 2019 from a prospectively collected database. Spinal root motor contributions and injury were determined using Active Movement Scale (AMS) scores at 6 weeks of age and used to predict contracture development. RESULTS: Of the 171 children that met inclusion criteria, 87% (n = 149) had upper plexus injuries. The mean age at the time of evaluation for an elbow contracture was 21.4 ± 12.7 months. The prevalence of elbow flexion contractures was 22% (n = 38), with mean onset at 13.4 ± 11.0 months. Mean contracture degree was -10.8 ± -6.9 degrees with 76% (n = 29) <-10 degrees. AMS shoulder abduction, flexion, and external rotation; elbow flexion; forearm supination; and wrist extension scores at a mean 2.3 ± 1.4 months were significantly lower in children who developed elbow flexion contractures (p < 0.001). Logistic regression found that low AMS elbow flexion with high elbow extension scores were a significant (p < 0.003) predictor of elbow contracture development. CONCLUSIONS: The prevalence of elbow flexion contractures in early childhood is greater than previously understood. These findings indicate that C5-C6 injury affecting elbow flexion with relative preservation of elbow extension is a predictor of contracture development. Further research is needed to investigate the nature and sequelae of C5-C6 injury and its effects on elbow flexion contracture development.

Functional Anatomy of Urogenital Hiatus Closure: the Perineal Complex Triad Hypothesis.

INTRODUCTION: Urogenital hiatus enlargement is a critical factor associated with prolapse and operative failure. This study of the perineal complex was performed to understand how interactions among its three structures: the levator ani, perineal membrane, and perineal body-united by the vaginal fascia-work to maintain urogenital hiatus closure. METHODS: Magnetic resonance images from 30 healthy nulliparous women with 3D reconstruction of selected subjects were used to establish overall geometry. Connection points and lines of action were based on perineal dissection in 10 female cadavers (aged 22-86 years), cross sections of 4 female cadavers (aged 14-35 years), and histological sections (cadavers aged 16 and 21 years). RESULTS: The perineal membrane originates laterally from the ventral two thirds of the ischiopubic rami and attaches medially to the perineal body and vaginal wall. The levator ani attaches to the perineal membrane's cranial surface, vaginal fascia, and the perineal body. The levator line of action in 3D reconstruction is oriented so that the levator pulls the medial perineal membrane cranio-ventrally. In cadavers, simulated levator contraction and relaxation along this vector changes the length of the membrane and the antero-posterior diameter of the urogenital hiatus. Loss of the connection of the left and right perineal membranes through the perineal body results in diastasis of the levator and a widened hiatus, as well as a downward rotation of the perineal membrane. CONCLUSION: Interconnections involving the levator ani muscles, perineal membrane, perineal body, and vaginal fascia form the perineal complex surrounding the urogenital hiatus in an arrangement that maintains hiatal closure.

Unilateral diaphragmatic paralysis and complete brachial plexus injury in a complex birth injury: A rare case report mimicking Tarlov cyst and review of literature.

The rare occurrence of Tarlov cysts in pediatric patients, particularly in the context of complex birth injuries, necessitates thorough evaluation and tailored management approaches. A comprehensive understanding of the clinical significance and optimal treatment strategies for this unique combination is crucial to ensure effective and individualized care for affected children.

Nerve Tracing in Juvenile Rats: A Feasible Model for the Study of Brachial Plexus Birth Palsy and Cocontractions?

Brachial plexus birth injuries cause diminished motor function in the upper extremity. The most common sequel is internal rotation contracture. A number of these patients also suffer from cocontractions, preventing the use of an otherwise good passive range of motion in the shoulder. One theory behind the co-contracture problem is that injured nerve fibers grow into distal support tissue not corresponding to the proximal support tissue, resulting in reinnervation of the wrong muscle groups. To further elucidate this hypothesis, we used rat neonates to investigate a possible model for the study of cocontractions in brachial plexus birth injuries. Five-day-old rats were subjected to a crush injury to the C5-C6 roots. After a healing period of 4 weeks, the infraspinatus muscle was injected with Fluoro-Gold. A week later, the animals were perfused and spinal cords harvested and sectioned. Differences in the uptake of Fluoro-Gold and NeuN positive cells of between sides of the spinal cord were recorded. We found a larger amount of Fluoro-Gold positive cells on the uninjured side, while the injured side had positive cells dispersed over a longer area in the craniocaudal direction. Our findings indicate that the method can be used to trace Fluoro-Gold from muscle through a neuroma. Our results also indicate that a neuroma in continuity somewhat prevents the correct connection from being established between the motor neuron pool in the spinal cord and target muscle and that some neurons succumb to a crushing injury. We also present future research ideas.

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.

Effect of nonsteroidal anti-inflammatory drugs on pelvic floor muscle regeneration in a preclinical birth injury rat model.

BACKGROUND: Pelvic floor muscle injury is a common consequence of vaginal childbirth. Nonsteroidal anti-inflammatory drugs are widely used postpartum analgesics. Multiple studies have reported negative effects of these drugs on limb muscle regeneration, but their impact on pelvic floor muscle recovery following birth injury has not been explored. OBJECTIVE: Using a validated rat model, we assessed the effects of nonsteroidal anti-inflammatory drug on acute and longer-term pelvic floor muscle recovery following simulated birth injury. STUDY DESIGN: Three-month old Sprague Dawley rats were randomly assigned to the following groups: (1) controls, (2) simulated birth injury, (3) simulated birth injury+nonsteroidal anti-inflammatory drug, or (4) nonsteroidal anti-inflammatory drug. Simulated birth injury was induced using a well-established vaginal balloon distension protocol. Ibuprofen was administered in drinking water (0.2 mg/mL), which was consumed by the animals ad libitum. Animals were euthanized at 1, 3, 5, 7, 10, and 28 days after birth injury/ibuprofen administration. The pubocaudalis portion of the rat levator ani, which, like the human pubococcygeus, undergoes greater parturition-associated strains, was harvested (N=3-9/time point/group). The cross-sectional areas of regenerating (embryonic myosin heavy chain+) and mature myofibers were assessed at the acute and 28-day time points, respectively. The intramuscular collagen content was assessed at the 28-day time point. Myogenesis was evaluated using anti-Pax7 and anti-myogenin antibodies to identify activated and differentiated muscle stem cells, respectively. The overall immune infiltrate was assessed using anti-CD45 antibody. Expression of genes coding for pro- and anti-inflammatory cytokines was assessed by quantitative reverse transcriptase polymerase chain reaction at 3, 5, and 10 days after injury. RESULTS: The pubocaudalis fiber size was significantly smaller in the simulated birth injury+nonsteroidal anti-inflammatory drug compared with the simulated birth injury group at 28 days after injury (P<.0001). The median size of embryonic myosin heavy chain+ fibers was also significantly reduced, with the fiber area distribution enriched with smaller fibers in the simulated birth injury+nonsteroidal anti-inflammatory drug group relative to the simulated birth injury group at 3 days after injury (P<.0001), suggesting a delay in the onset of regeneration in the presence of nonsteroidal anti-inflammatory drugs. By 10 days after injury, the median embryonic myosin heavy chain+ fiber size in the simulated birth injury group decreased from 7 days after injury (P<.0001) with a tight cross-sectional area distribution, indicating nearing completion of this state of regeneration. However, in the simulated birth injury+nonsteroidal anti-inflammatory drug group, the size of embryonic myosin heavy chain+ fibers continued to increase (P<.0001) with expansion of the cross-sectional area distribution, signifying a delay in regeneration in these animals. Nonsteroidal anti-inflammatory drugs decreased the muscle stem cell pool at 7 days after injury (P<.0001) and delayed muscle stem cell differentiation, as indicated by persistently elevated number of myogenin+ cells 7 days after injury (P<.05). In contrast, a proportion of myogenin+ cells returned to baseline by 5 days after injury in the simulated birth injury group. The analysis of expression of genes coding for pro- and anti-inflammatory cytokines demonstrated only transient elevation of Tgfb1 in the simulated birth injury+nonsteroidal anti-inflammatory drug group at 5 but not at 10 days after injury. Consistently with previous studies, nonsteroidal anti-inflammatory drug administration following simulated birth injury resulted in increased deposition of intramuscular collagen relative to uninjured animals. There were no significant differences in any outcomes of interest between the nonsteroidal anti-inflammatory drug group and the unperturbed controls. CONCLUSION: Nonsteroidal anti-inflammatory drugs negatively impacted pelvic floor muscle regeneration in a preclinical simulated birth injury model. This appears to be driven by the negative impact of these drugs on pelvic muscle stem cell function, resulting in delayed temporal progression of pelvic floor muscle regeneration following birth injury. These findings provide impetus to investigate the impact of postpartum nonsteroidal anti-inflammatory drug administration on muscle regeneration in women at high risk for pelvic floor muscle injury.