The diagnostic value of CT myelography, MR myelography, and both in neonatal brachial plexus palsy

Evaluation of Infantile Brachial Plexopathy Using 3T MRI and High-Resolution Ultrasound: Experience From a Tertiary Care Centre

BACKGROUND

Currently, clinical assessment is the main tool for the evaluation of brachial plexus injury, complemented by electrophysiologic studies (EPS), and imaging studies whenever available. Imaging plays an important role as it enables the differentiation of pre-ganglionic and postganglionic injuries, and adds objectivity to presurgical evaluation.

OBJECTIVES

The primary objective was to evaluate the utility of magnetic resonance imaging (MRI) and high-resolution ultrasonography (USG) in the localization and characterization of brachial plexus injury in infants.

MATERIALS AND METHODS

In this prospective study, 34 infants with signs and symptoms of brachial plexus injury were evaluated by clinical examination, EPS, MRI, and USG. Imaging findings were correlated with intraoperative findings in infants who underwent surgical management. The association between EPS and MRI findings, and USG and MRI findings were assessed using Fisher's exact test. Semi-quantitative subjective analysis of various MRI sequences was done as well.

RESULTS

The most common findings of preganglionic injury and postganglionic injury, in our study, were pseudomeningocele and nerve thickening, respectively. MRI detection of injuries had a significant association with EPS findings. All MRI-detected injuries had a muscle power of grade 3 or less. muscle. Three-dimensional (3D) short tau inversion recovery (STIR) sequence was found to be superior for detecting postganglionic injuries (P < 0.05).

CONCLUSION

Imaging studies enable localization of the site of injury, determining the extent, and nature/morphology of injury. The gamut of findings obtained from MRI is far wider compared to that from USG. USG can be used as the first-line screening investigation.

Permanent Brachial Plexus Birth Injury: Helsinki Shoulder Protocol

Passive shoulder exercises from birth and ultrasound screening from 3 to 12 months. Botox is given to shoulder internal rotators and a bracing commenced, if alpha-angle exceeds 30°, or passive shoulder external rotation is below 70 degrees. Plexus reconstruction is recommended to children with root avulsion(s) on magnetic resonance imaging or 3-month Toronto Test Score < 3.5. Specific neurotization is recommended to children without avulsions, but lack of progress in healing. Shoulder dysplasia was diagnosed in 49% of 270 patients with permanent brachial plexus birth injury in our catchment area from 1995 to 2021. The age at detection of shoulder dysplasia dropped from mean 5.4 years in children born before 2000 to mean 3.9 months in children born after 2009. Botox was given to 57% of the patients born after 2009. Rate of shoulder relocation decreased from 28 to 7% while mean active shoulder external rotation in adduction increased from 2 to 46°.

Differences in the surgical treatment of adult and pediatric brachial plexus injuries among peripheral nerve surgeons

OBJECTIVES

Peripheral nerve surgeons disagree on the optimal timing and treatment of brachial plexus injuries (BPI). This study aims to survey peripheral nerve surgeons on their management of BPI, including disagreement.

METHODS

Surgeons responded to a case-based survey involving traumatic and birth injuries leading to BPI involving the upper and lower trunks, and pre- and post-ganglionic injuries.

RESULTS

Out of 255 invited surgeons, 154 participated, with specialties of Neurosurgery (33.7%), Plastic surgery (32.5%), and Orthopedics (32.5%). For the adult C5-6 avulsion injury, 97.4% agreed they would operate. There was 46.2% disagreement regarding the pediatric upper trunk neuroma-in-continuity case, and similar disagreement (50.0%) was recorded on exploring the brachial plexus for a pediatric lower trunk injury case. High percentages of surgeons were more likely to explore the plexus, such as at upper BPI. Also, most participants reported nerve transfer for the upper and lower trunk avulsion injuries, but there was 55.6% disagreement regarding nerve transfer for the infant with the upper trunk neuroma-in-continuity. Among those elected to perform nerve transfer, most (70.0%-84.5%) would perform an accessory-to-suprascapular nerve transfer for upper BPI, while brachialis-to-anterior interosseous and supinator branch of the radial nerve-to-posterior interosseous were preferred for lower BPI (30.0%-55.9%).

CONCLUSIONS

Substantial disagreement exists among peripheral nerve surgeons in managing adult and pediatric BPI. In adult BPI, most prefer to operate at the time of the presentation and perform extensive nerve transfers. The accessory-suprascapular transfer was recommended for upper BPI, while brachialis and radial nerves were preferred for lower BPI. The most significant disagreements exist in operation and nerve transfer for pediatric upper BPI and brachial plexus explorations. Geography, specialty, and operative volume contribute to the differences seen.

Brachial Plexus Birth Injury: A Review of Neurology Literature Assessing Variability and Current Recommendations

BACKGROUND

Publications regarding the epidemiology and management of brachial plexus birth injury (BPBI) were evaluated to investigate treatment guidelines for children with BPBI.

METHODS

A search of neurology literature from 1990 to 2019 was performed using PubMed, Scopus, and Medline. Data including incidence, risk factors, spontaneous recovery rates, imaging studies, treatment recommendations, and indications and timing for surgery were collected.

RESULTS

A total of 46 total studies were reviewed. Reported incidence rates for BPBI ranged from 0.3 to 3 per 1000 births. Spontaneous recovery rates had an average reported range from 66% to 75%. Physical and occupational therapy were recommended in 37% of articles. Computed tomographic myelogram and magnetic resonance imaging of the brachial plexus were the most commonly recommended imaging studies for BPBI. Timelines for surgical interventions ranged from age three to nine months. Early referral was recommended in 28% of the articles included in the review.

CONCLUSIONS

Given the inconsistencies in spontaneous recovery rates, imaging recommendations, and timing of referral, establishing consistent clinical guidelines for patients with BPBI is crucial for management. Early referral to specialists for evaluation and treatment may improve outcomes in children with BPBI.

Radiographic imaging modalities for perinatal brachial plexus palsy: a systematic review

PURPOSE

Perinatal brachial plexus palsy (PBPP) has a wide spectrum of clinical symptoms that can range from incomplete paresis of the affected extremity to flaccid arm paralysis. Although there is a high rate of spontaneous recovery within the first two years of life, it remains challenging to determine which patients will benefit most from surgical intervention. The diagnostic and predictive use of various imaging modalities has been described in the literature, but there is little consensus on approach or algorithm. The anatomic, pathophysiological, and neurodevelopmental characteristics of the neonatal and infant patient population affected by PBPP necessitate thoughtful consideration prior to selecting an imaging modality.

METHODS

A systematic review was conducted using six databases. Two reviewers independently screened articles published through October 2021.

RESULTS

Literature search produced 10,329 publications, and 22 articles were included in the final analysis. These studies included 479 patients. Mean age at time of imaging ranged from 2.1 to 12.8 months and investigated imaging modalities included MRI (18 studies), ultrasound (4 studies), CT myelography (4 studies), and X-ray myelography (1 study). Imaging outcomes were compared against surgical findings (16 studies) or clinical examination (6 studies), and 87.5% of patients underwent surgery.

CONCLUSION

This systematic review addresses the relative strengths and challenges of common radiologic imaging options. MRI is the most sensitive and specific for identifying preganglionic nerve injuries such as pseudomeningoceles and rootlet avulsion, the latter of which has the poorest prognosis in this patient population and often dictates the need for surgical intervention.

Diagnostic Ability of Ultrasonography in Brachial Plexus Root Injury at Different Stages Post-trauma

Brachial plexus (BP) root injury often results in disability of the upper extremities. Improvements in high-frequency ultrasonography have enabled the visualization of BP nerve roots. This study was aimed at quantifying the diagnostic accuracy of ultrasonography in BP root injury at different stages post-trauma. A consecutive series of 170 patients with BP root injury between 2015 and 2019 were studied retrospectively and divided into three groups on the basis of time between injury and ultrasound examination (≤1 mo, 1-3 mo, >3 mo). Diagnosis of complete BP root injury under ultrasound was determined using a pre-defined criterion, including pseudomeningocele, retraction and rupture. Diagnostic accuracy was calculated based on surgical findings and intra-operative electrophysiological tests. Rates of detection of the cervical (C5-C8) and thoracic (T1) nerve roots under ultrasound were 99.4%, 99.4%, 99.4%, 95.9% and 79.4%, respectively. The sensitivity for complete BP root injury was 0.74, and the specificity was 0.91. No significant differences in sensitivity or specificity were observed across time stages. Ultrasound exhibited substantial consistency with surgical findings (κ = 0.70) for complete BP root injury at any stage post-injury. Ultrasound can be an optional method of diagnosis of complete BP root injury at an early stage post-injury.

Brachial Plexus Birth Palsy: Practical Concepts for Radiologists

Brachial plexus birth palsy (BPBP) is classified as a preganglionic or postganglionic injury based on the site of injury. Most patients recover spontaneously and are followed up with clinical evaluation; however, permanent sequelae are not uncommon. For patients with persistent neurologic deficits, clinical and radiologic evaluation is crucial. Untreated BPBP can progress to significant sequelae, such as muscle contractures and glenohumeral dysplasia (GHD). Timely characterization of these entities based on different imaging modalities is a high priority for optimal patient outcomes. We describe the anatomy and pathogenesis, as well as the different imaging modalities involved in the evaluation and classification of BPBP and GHD.

Axial T2-DRIVE MRI myelography is highly accurate in diagnosing preganglionic traumatic brachial plexus injuries: why pseudomeningoceles should not be used as a primary diagnostic sign

AIM

To evaluate the accuracy of brachial plexus magnetic resonance imaging (MRI) utilising the three-dimensional (3D)-T2-turbo spin echo (TSE) with 90° flip-back pulse ("DRIVE") myelography in detecting nerve root avulsions in patients with traumatic brachial plexus injuries.

MATERIALS AND METHODS

A prospective study of 24 patients planned for brachial plexus reconstructive surgery following trauma from April 2019 to October 2021. Preoperative 1.5 T MRI of the brachial plexus was performed utilising axial T2-DRIVE, looking for signs of avulsions (absent dural rootlets, pauci-rootlet appearance and thickened rootlets; the presence of pseudomeningoceles was noted only as an ancillary sign). Comparison against the reference standard of extra-dural brachial plexus exploration was performed. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated.

RESULTS

Eighteen patients had at least one root avulsion at surgery, five showed isolated post-ganglionic injuries, and one had normal brachial plexus exploration. Thirty-nine avulsed roots were found at surgery (out of 108 explored in 24 patients). Preoperative MRI identified the specific avulsed roots accurately in each patient. Two false-positive diagnoses of C5 and C6 avulsions were made in one patient. On MRI, absence of the rootlets was seen in 73.2% (n=30) of avulsions, pauci-rootlet appearance in 24.4% (n=10) and thickening of the rootlets in 2.4% (n=1). Pseudomeningoceles were found only in 68.3% (n=28) of avulsions. The overall sensitivity, specificity, PPV, NPV, and accuracy of MRI were 100%, 97.1%, 95.1%, 100% and 98.1%, respectively.

CONCLUSION

3D-T2-DRIVE is highly accurate in evaluating pre-ganglionic traumatic brachial plexus injuries. Pseudomeningoceles can be considered an ancillary feature of avulsion given the clarity of rootlet visualisation by this sequence.

Magnetic resonance imaging of the brachial plexus. Part 2: Traumatic injuries

The most common indications for magnetic resonance imaging (MRI) of the brachial plexus (BP) are traumatic injuries. The role of MRI of the BP has increased because of recent trends favoring earlier surgery. Determining preganglionic vs. postganglionic injury is essential, as different treatment strategies are required. Thus, MRI of the BP should be supplemented with cervical spine MRI to assess the intradural part of the spinal nerves, including highly T2-weighted techniques. Acute preganglionic injuries usually manifest as various combinations of post-traumatic pseudomeningocele, the absence of roots, deformity of nerve root sleeves, displacement of the spinal cord, hemorrhage in the spinal canal, presence of scars in the spinal canal, denervation of the back muscles, and syrinx. Spinal nerve root absence is more specific than pseudomeningocele on MRI. Acute postganglionic injuries can present as lesions in continuity or tears. The following signs indicate injury to the BP: side-to-side difference, swelling, partial, or total BP rupture. Injury patterns and localization are associated with the mechanism of trauma, which implies a significant role for MRI in the work-up of patients.

The identification and description of traumatic lesions involving the brachial plexus need to be systematic and detailed. Using an appropriate MRI protocol, obtaining details about the injury, applying a systematic anatomical approach, and correlating imaging findings to relevant clinical data to make a correct diagnosis. Information about the presence or suspicion of root avulsion should always be provided.

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Trauma is the most common indication for MRI of the brachial plexus.

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MRI of the brachial plexus should include cervical spine MRI.

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Spinal nerve root absence is seen in preganglionic injuries.

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Determining preganglionic vs. postganglionic injury is essential for treatment planning.

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Appropriate MRI rapport is crucial in communication with the clinician.

MRI evaluation of nerve root avulsion in neonatal brachial plexus palsy: understanding the presence of isolated dorsal/ventral rootlet disruption

OBJECTIVE

The evaluation, treatment, and prognosis of neonatal brachial plexus palsy (NBPP) continues to have many areas of debate, including the use of ancillary testing. Given the continued improvement in imaging, it is important to revisit its utility. Nerve root avulsions have historically been identified by the presence of pseudomeningoceles or visible ruptures. This "all-or-none" definition of nerve root avulsions has many implications for the understanding and management of NBPP, especially as characterization of the proximal nerve root as a potential donor remains critical. This study examined the ability of high-resolution MRI to more specifically define the anatomy of nerve root avulsions by individually examining the ventral and dorsal rootlets as they exit the spinal cord.

METHODS

This is a retrospective review of patients who had undergone brachial plexus protocol MRI for clinical evaluation of NBPP at a single institution. Each MR image was independently reviewed by a board-certified neuroradiologist, who was blinded to both established diagnosis/surgical findings and laterality. Each dorsal and ventral nerve rootlet bilaterally from C5 to T1 was evaluated from the spinal cord to its exit in the neuroforamen. Each rootlet was classified as avulsed, intact, or undeterminable.

RESULTS

Sixty infants underwent brachial plexus protocol MRI from 2010 to 2018. All infants were included in this study. Six hundred individual rootlets were analyzed. There were 49 avulsed nerve rootlets in this cohort. Twenty-nine (59%) combined dorsal/ventral avulsions involved both the ventral and dorsal rootlets, and 20 (41%) were either isolated ventral or isolated dorsal rootlet avulsions. Of the isolated avulsion injuries, 13 (65%) were dorsal only, meaning that the motor rootlets were intact.

CONCLUSIONS

A closer look at nerve root avulsions with MRI demonstrates a significant prevalence (approximately 41%) of isolated dorsal or ventral nerve rootlet disruptions. This finding implies that nerve roots previously labeled as "avulsed" but with only isolated dorsal (sensory) rootlet avulsion can yet provide donor fascicles in reconstruction strategies. A majority (99%) of the rootlets can be clearly visualized with MRI. These findings may significantly impact the clinical understanding of neonatal brachial plexus injury and its treatment.

Contemporary imaging of the pediatric shoulder: pearls and pitfalls

In skeletally immature patients, the presence of growth plates and articular cartilage of the shoulder can create a predisposition for unique injuries not observed in adults. Furthermore, increasing participation in sports by children and adolescents appears to be leading to a corresponding increase in the number of sports-related injuries. The importance of radiologists being familiar with pediatric shoulder imaging and its associated injuries is therefore growing. In this article, we review the normal development and maturation pattern of ossification centers of the shoulder from the early gestational period through adolescence. Brachial plexus birth palsy, physeal injuries, shoulder dislocation, and internal impingement are discussed within the context of the child's age and the mechanism of injury to guide radiologists to a correct diagnosis.

Clinical significance of cervical MRI in brachial plexus birth injury

Background and purpose - Patient selection for nerve surgery in brachial plexus birth injury (BPBI) is difficult. Decision to operate is mostly based on clinical findings. We assessed whether MRI improves patient selection. Patients and methods - 157 BPBI patients were enrolled for a prospective study during 2007-2015. BPBI was classified at birth as global plexus injury (GP) or upper plexus injury (UP). The global plexus injury was subdivided into flail upper extremity (FUE) and complete plexus involvement (CP). Patients were seen at set intervals. MRI was scheduled for patients that had either GP at 1 month of age or UP with no antigravity biceps function by 3 months of age. Type (total or partial avulsion, thinned root), number and location of root injuries and pseudomeningoceles (PMC) were registered. Position of humeral head (normal, subluxated, dislocated) and glenoid shape (normal, posteriorly rounded, pseudoglenoid) were recorded. Outcome was assessed at median 4.5 years (1.6-8.6) of age. Results - Cervical MRI was performed on 34/157 patients at median 3.9 months (0.3-14). Total root avulsions (n = 1-3) were detected on MRI in 12 patients (8 FUE, 4 CP). Reconstructive surgery was performed on 10/12 with total avulsions on MRI, and on all 10 with FUE at birth. Sensitivity and specificity of MRI in detecting total root avulsions was 0.88 and 1 respectively. Posterior shoulder subluxation/dislocation was seen in 15/34 patients (3.2-7.7 months of age). Interpretation - Root avulsion(s) on MRI and flail upper extremity at birth are both good indicators for nerve surgery in brachial plexus birth injury. Shoulder pathology develops very early in permanent BPBI.

An Update on the Management of Neonatal Brachial Plexus Palsy-Replacing Old Paradigms: A Review

IMPORTANCE

Neonatal brachial plexus palsy (NBPP) can result in persistent deficits for those who develop it. Advances in surgical technique have resulted in the availability of safe, reliable options for treatment. Prevailing paradigms include, "all neonatal brachial plexus palsy recovers," "wait a year to see if recovery occurs," and "don't move the arm." Practicing by these principles places these patients at a disadvantage. Thus, the importance of this review is to provide an update on the management of NBPP to replace old beliefs with new paradigms.

OBSERVATIONS

Changes within denervated muscle begin at the moment of injury, but without reinnervation become irreversible 18 to 24 months following denervation. These time-sensitive, irreversible changes are the scientific basis for the recommendations herein for the early management of NBPP and put into question the old paradigms. Early referral has become increasingly important because improved outcomes can be achieved using new management algorithms that allow surgery to be offered to patients unlikely to recover sufficiently with conservative management. Mounting evidence supports improved outcomes for appropriately selected patients with surgical management compared with natural history. Primary nerve surgery options now include nerve graft repair and nerve transfer. Specific indications continue to be elucidated, but both techniques offer a significant chance of restoration of function.

CONCLUSIONS AND RELEVANCE

Mounting data support both the safety and effectiveness of surgery for patients with persistent NBPP. Despite this support, primary nerve surgery for NBPP continues to be underused. Surgery is but one part of the multidisciplinary care of NBPP. Early referral and implementation of multidisciplinary strategies give these children the best chance of functional recovery. Primary care physicians, nerve surgeons, physiatrists, and occupational and physical therapists must partner to continue to modify current treatment paradigms to provide improved quality care to neonates and children affected by NBPP.

Oberlin transfer compared with nerve grafting for improving early supination in neonatal brachial plexus palsy

OBJECTIVE The use of nerve transfers versus nerve grafting for neonatal brachial plexus palsy (NBPP) remains controversial. In adult brachial plexus injury, transfer of an ulnar fascicle to the biceps branch of the musculocutaneous nerve (Oberlin transfer) is reportedly superior to nerve grafting for restoration of elbow flexion. In pediatric patients with NBPP, recovery of elbow flexion and forearm supination is an indicator of resolved NBPP. Currently, limited evidence exists of outcomes for flexion and supination when comparing nerve transfer and nerve grafting for NBPP. Therefore, the authors compared 1-year postoperative outcomes for infants with NBPP who underwent Oberlin transfer versus nerve grafting. METHODS This retrospective cohort study reviewed patients with NBPP who underwent Oberlin transfer (n = 19) and nerve grafting (n = 31) at a single institution between 2005 and 2015. A single surgeon conducted intraoperative exploration of the brachial plexus and determined the surgical nerve reconstruction strategy undertaken. Active range of motion was evaluated preoperatively and postoperatively at 1 year. RESULTS No significant difference between treatment groups was observed with respect to the mean change (pre- to postoperatively) in elbow flexion in adduction and abduction and biceps strength. The Oberlin transfer group gained significantly more supination (100° vs 19°; p < 0.0001). Forearm pronation was maintained at 90° in the Oberlin transfer group whereas it was slightly improved in the grafting group (0° vs 32°; p = 0.02). Shoulder, wrist, and hand functions were comparable between treatment groups. CONCLUSIONS The preliminary data from this study demonstrate that the Oberlin transfer confers an advantageous early recovery of forearm supination over grafting, with equivalent elbow flexion recovery. Further studies that monitor real-world arm usage will provide more insight into the most appropriate surgical strategy for NBPP.

Neonatal Magnetic Resonance Imaging Without Sedation Correlates With Injury Severity in Brachial Plexus Birth Palsy

PURPOSE

Which infants with brachial plexus birth palsy (BPBP) should undergo microsurgical plexus reconstruction remains controversial. The current gold standard for the decision for plexus reconstruction is serial clinical examinations, but this approach obviates the possibility of early surgical treatment. We hypothesize that a new technique using 3-dimensional volumetric proton density magnetic resonance imaging (MRI) without sedation can evaluate the severity of BPBP injury earlier than serial clinical examinations.

METHODS

Infants were prospectively enrolled prior to 12 weeks of age and imaged using 3 Tesla MRI without sedation. Clinical scores were collected at all visits. The imaging findings were graded based on the number of injured levels and the severity of each injury, and a radiological score was calculated. All infants were followed at least until the decision for surgery was made based on clinical examination.

RESULTS

Nine infants completed the MRI scan and clinical follow-up. The average Toronto score at presentation was 4.4 out of 10 (range, 0-8.2); the average Active Movement Scale score was 50 out of 105 (range, 0-86). Four infants required surgery: 2 because of a flail limb and Horner syndrome and 2 owing to failure to recover antigravity elbow flexion by age 6 months. Radiological scores ranged from 0 to 18 out of a maximum score of 25. The average radiological score for those infants who required surgery was 12 (range, 6.5-18), whereas the average score for infants who did not require surgery was 3.5 (range, 0-8).

CONCLUSIONS

Three-dimensional proton density MRI can evaluate spinal nerve roots in infants without the need for radiation, contrast agents, or sedation. These data suggest that MRI can help determine the severity of injury earlier than clinical examination in infants with BPBP, although further study of a larger sample of infants with varying severity of disease is necessary.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic II.

The natural history and management of brachial plexus birth palsy

Brachial plexus birth palsy (BPBP) is an upper extremity paralysis that occurs due to traction injury of the brachial plexus during childbirth. Approximately 20 % of children with brachial plexus birth palsy will have residual neurologic deficits. These permanent and significant impacts on upper limb function continue to spur interest in optimizing the management of a problem with a highly variable natural history. BPBP is generally diagnosed on clinical examination and does not typically require cross-sectional imaging. Physical examination is also the best modality to determine candidates for microsurgical reconstruction of the brachial plexus. The key finding on physical examination that determines need for microsurgery is recovery of antigravity elbow flexion by 3-6 months of age. When indicated, both microsurgery and secondary shoulder and elbow procedures are effective and can substantially improve functional outcomes. These procedures include nerve transfers and nerve grafting in infants and secondary procedures in children, such as botulinum toxin injection, shoulder tendon transfers, and humeral derotational osteotomy.

Recovery of upper extremity function following endoscopically assisted contralateral C7 transfer for obstetrical brachial plexus injury

Transfer of the contralateral C7 nerve for reconstruction of the brachial plexus in infants with obstetrical brachial plexus injury has rarely been reported. We developed a new endoscopy-assisted technique via the prevertebral (retroesophageal) route for the transfer of the contralateral C7 nerve in reconstruction of the brachial plexus. The reconstruction was performed in 20 infants (14 boys and six girls). Motor recovery was assessed using the Gilbert and Raimondi scales. The Narakas Sensory Grading System was used to evaluate hand sensation. The mean follow-up period was 45 months (SD 18.2). Of the 20 children, nine had contralateral C7 transfer to lower nerve roots, two had transfer to upper nerve roots and nine had transfer to both upper and lower roots. The postoperative shoulder and elbow functions were good or satisfactory according to the Gilbert classification in all children whose preoperative scores were poor. All patients with lower roots reconstruction (9) had satisfactory hand function. A total of 15 children had a Narakas score of S3. Our technique enables safe contralateral C7 transfer to the avulsed roots in severe obstetrical brachial plexus injury infants with a satisfactory functional recovery.

LEVEL OF EVIDENCE

Level IV.

Non-Sedated Rapid Volumetric Proton Density MRI Predicts Neonatal Brachial Plexus Birth Palsy Functional Outcome

BACKGROUND AND PURPOSE

The current prognostic biomarker of functional outcome in brachial plexus birth palsy is serial clinical examination throughout the first 6 months of age. This can delay surgical treatment and prolong parental anxiety in neonates who will recover spontaneously. A potentially superior biomarker is a volumetric proton density MRI performed at clinical presentation and within the first 12 weeks of life, providing a high spatial and contrast resolution examination in 4 minutes.

METHODS

Nine neonates ranging in age from 4 to 9 weeks who presented with brachial plexus birth palsy were enrolled. All subjects underwent non-sedated 3 Tesla MRI with Cube Proton Density MRI sequence at the same time as their initial clinical visit. Serial clinical examinations were conducted at routine 4 week intervals and the functional performance scores were recorded. MRI findings were divided into pre-ganglionic and post-ganglionic injuries and a radiological scoring system (Shriners Radiological Score) was developed for this study.

RESULTS

Proton Density MRI was able to differentiate between pre-ganglionic and post-ganglionic injuries. Radiological scores (Shriners Radiological Score) correlated better with functional performance at 6 months of age (P = .022) than the initial clinical examinations (Active Movement Scale P = .213 and Toronto P = .320).

CONCLUSIONS

Rapid non-sedated volumetric Cube Proton Density MRI protocol performed at initial clinical presentation can accurately grade severity of brachial plexus birth palsy injury and predict functional performance at 6 months of age.

Peripartum and neonatal factors associated with the persistence of neonatal brachial plexus palsy at 1 year: a review of 382 cases

OBJECTIVE Neonatal brachial plexus palsy (NBPP) occurs due to the stretching of the nerves of the brachial plexus before, during, or after delivery. NBPP can resolve spontaneously or become persistent. To determine if nerve surgery is indicated, predicting recovery is necessary but difficult. Historical attempts explored the association of recovery with only clinical and electrodiagnostic examinations. However, no data exist regarding the neonatal and peripartum factors associated with NBPP persistence. METHODS This retrospective cohort study involved all NBPP patients at the University of Michigan between 2005 and 2015. Peripartum and neonatal factors were assessed for their association with persistent NBPP at 1 year, as defined as the presence of musculoskeletal contractures or an active range of motion that deviated from normal by > 10° (shoulder, elbow, hand, and finger ranges of motion were recorded). Standard statistical methods were used. RESULTS Of 382 children with NBPP, 85% had persistent NBPP at 1 year. A wide range of neonatal and peripartum factors was explored. We found that cephalic presentation, induction or augmentation of labor, birth weight > 9 lbs, and the presence of Horner syndrome all significantly increased the odds of persistence at 1 year, while cesarean delivery and Narakas Grade I to II injury significantly reduced the odds of persistence. CONCLUSIONS Peripartum/neonatal factors were identified that significantly altered the odds of having persistent NBPP at 1 year. Combining these peripartum/neonatal factors with previously published clinical examination findings associated with persistence should allow the development of a prediction algorithm. The implementation of this algorithm may allow the earlier recognition of those cases likely to persist and thus enable earlier intervention, which may improve surgical outcomes.

Nerve Transfers in Birth Related Brachial Plexus Injuries: Where Do We Stand?

This article reviews the assessment and management of obstetrical brachial plexus palsy. The potential role of distal nerve transfers in the treatment of infants with Erb's palsy is discussed. Current evidence for motor outcomes after traditional reconstruction via interpositional nerve grafting and extraplexal nerve transfers is reviewed and compared with the recent literature on intraplexal distal nerve transfers in obstetrical brachial plexus injury.

Clinical and neurobiological advances in promoting regeneration of the ventral root avulsion lesion

Root avulsions due to traction to the brachial plexus causes complete and permanent loss of function. Until fairly recent, such lesions were considered impossible to repair. Here we review clinical repair strategies and current progress in experimental ventral root avulsion lesions. The current gold standard in patients with a root avulsion is nerve transfer, whereas reimplantation of the avulsed root into the spinal cord has been performed in a limited number of cases. These neurosurgical repair strategies have significant benefit for the patient but functional recovery remains incomplete. Developing new ways to improve the functional outcome of neurosurgical repair is therefore essential. In the laboratory, the molecular and cellular changes following ventral root avulsion and the efficacy of intervention strategies have been studied at the level of spinal motoneurons, the ventral spinal root and peripheral nerve, and the skeletal muscle. We present an overview of cell-based pharmacological and neurotrophic factor treatment approaches that have been applied in combination with surgical reimplantation. These interventions all demonstrate neuroprotective effects on avulsed motoneurons, often accompanied with various degrees of axonal regeneration. However, effects on survival are usually transient and robust axon regeneration over long distances has as yet not been achieved. Key future areas of research include finding ways to further extend the post-lesion survival period of motoneurons, the identification of neuron-intrinsic factors which can promote persistent and long-distance axon regeneration, and finally prolonging the pro-regenerative state of Schwann cells in the distal nerve.

International Federation of Societies for Surgery of the Hand Committee report: the role of nerve transfers in the treatment of neonatal brachial plexus palsy

Nerve transfers have gained popularity in the treatment of adult brachial plexus palsy; however, their role in the treatment of neonatal brachial plexus palsy (NBPP) remains unclear. Brachial plexus palsies in infants differ greatly from those in adults in the patterns of injury, potential for recovery, and influences of growth and development. This International Federation of Societies for Surgery of the Hand committee report on NBPP is based upon review of the current literature. We found no direct comparisons of nerve grafting to nerve transfer for primary reconstruction of NBPP. Although the results contained in individual reports that use each strategy for treatment of Erb palsy are similar, comparison of nerve transfer to nerve grafting is limited by inconsistencies in outcomes reported, by multiple confounding factors, and by small numbers of patients. Although the role of nerve transfers for primary reconstruction remains to be defined, nerve transfers have been found to be effective and useful in specific clinical circumstances including late presentation, isolated deficits, failed primary reconstruction, and multiple nerve root avulsions. In the case of NBPP more severe than Erb palsy, nerve transfers alone are inadequate to address all of the deficits and should only be considered as adjuncts if maximal re-innervation is to be achieved. Surgeons who commit to care of infants with NBPP need to avoid an over-reliance on nerve transfers and should also have the capability and inclination for brachial plexus exploration and nerve graft reconstruction.