Implications of median sensory study to the thumb and deltoid/biceps motor unit recruitment on identifying C6 root avulsion in upper neonatal brachial plexus palsy.

INTRODUCTION/AIMS: Anatomic representation suggests that a median sensory nerve conduction study recording the thumb (median D1 NCS) may effectively assess upper neonatal brachial plexus palsy (NBPP). We sought to determine the feasibility of technique, establish reference data, and assess its ability to: (a) identify focal upper plexus lesions; and (b) identify C6 root avulsion. In a secondary analysis, we explored the association between absence/presence of motor unit action potentials (MUAPs) during needle electromyography (EMG) of the deltoid and biceps brachii muscles and C6 avulsion status. METHODS: A retrospective chart review was performed of surgical patients with severe upper NBPP who ultimately underwent surgical reconstruction (between 2017 and 2020). Median D1 sensory nerve action potential (SNAP) amplitude ranges were determined in affected and contralateral limbs and analyzed by C6 root avulsion status. Also, presence/absence of MUAPs during EMG of the deltoid and biceps brachii was compared between C6 avulsion patients and controls. RESULTS: Thirty-eight patients were included in our analysis. A median D1 NCS study was readily performed, showing a contralateral limb mean amplitude of 27.42 µV (range, 3.8-54.7 µV). Most patients had a low ipsilateral median D1 SNAP amplitude, regardless of C6 avulsion status. Detectable MUAPs in either deltoid or biceps brachii on EMG were atypical in C6 root avulsion. DISCUSSION: The median D1 NCS identifies upper NBPP, but does not distinguish C6 avulsions from post-ganglionic lesions, likely due to the frequent co-occurrence of post-ganglionic axonal disruption. The presence of MUAPs on deltoid/biceps brachii EMG suggests C6 avulsion is unlikely.

Imaging the intermuscular septum in the context of ulnar neuropathy.

Impingement/entrapment of the ulnar nerve by the intermuscular septum at the distal arm is a common cause of recurrent or recalcitrant ulnar neuropathy following ulnar nerve decompression or anterior transposition. Primary entrapment/impingement of the ulnar nerve along the intermuscular septum may also occur. Evaluation with both ultrasound (US) and MRI can identify entrapment of the ulnar nerve at the intermuscular septum, while dynamic assessment with US can also identify dynamic subluxation of the ulnar nerve over the intermuscular septum.

Knowledge of neonatal brachial plexus palsy among medical professionals in North America.

PURPOSE: Early referral of neonatal brachial plexus palsy (NBPP) patients to multidisciplinary clinics is critical for timely diagnosis, treatment, and improved functional outcomes. In Saudi Arabia, inadequate knowledge regarding NBPP is a reason for delayed referral. We aimed to evaluate the knowledge of North American healthcare providers (HCPs) regarding the diagnosis, management, and prognosis of NBPP. METHODS: A 12-question survey regarding NBPP was distributed via electronic and paper formats to North American providers from various referring and treating specialties. NBPP knowledge was compared between Saudi Arabian vs. North American providers, referring vs. treating specialties, academic vs. community hospitals, and providers with self-reported confidence vs. nonconfidence in NBPP knowledge. RESULTS: Of the 273 surveys collected, 45% were from referring providers and 55% were from treating providers. Saudi Arabian and North American HCPs demonstrated similar NBPP knowledge except for potential etiologies for NBPP and surgery timing. In North America, referring and treating providers had similar overall knowledge of NBPP but lacked familiarity with its natural history. A knowledge gap existed between academic and community hospitals regarding timing of referral/initiation of physical/occupational therapy (PT/OT) and Horner's syndrome. Providers with self-reported confidence in treating NBPP had greater knowledge of types of NBPP and timing for PT/OT initiation. CONCLUSIONS: Overall, North American providers demonstrated adequate knowledge of NBPP. However, both eastern and western physicians remain overly optimistic in believing that most infants recover spontaneously. This study revealed a unique and universal knowledge gap in NBPP diagnosis, referral, and management worldwide. Continuous efforts to increase NBPP knowledge are indicated.

Assessment of variability in motor grading and patient-reported outcome reporting: a multi-specialty, multi-national survey.

BACKGROUND: The goal of this survey-based study was to evaluate the current practice patterns of clinicians who assess patients with peripheral nerve pathologies and to assess variance in motor grading on the Medical Research Council (MRC) scale using example case vignettes. METHODS: An electronic survey was distributed to clinicians who regularly assess patients with peripheral nerve pathology. Survey sections included (1) demographic data, (2) vignettes where respondents were asked to assess on the MRC scale, and (3) assessment of practice patterns regarding the use of patient-reported outcome measures. Inter-rater reliability statistics were calculated for the application of the MRC scale on example vignettes. RESULTS: There were 109 respondents. There was significant dispersion in motor grading seen on the example vignettes. For the raw responses grading the example vignettes on the MRC scale, Krippendorff's alpha was 0.788 (95% CI 0.604, 0.991); Gwet's AC2 was 0.808 (95% CI 0.683, 0.932); Fleiss' kappa was 0.416 (95% CI 0.413, 0.419). Most respondents reported not utilizing any patient-reported outcome measures across peripheral nerve pathologies. DISCUSSION: Our data show that there is significant disagreement among providers when applying the MRC scale. It is important for us to reassess our current tools for patient evaluation in order to improve upon both clinical evaluation and outcomes reporting. Consensus guidelines for outcomes reporting are needed, and domains outside of manual muscle testing should be included.

Minimally Invasive Ultrasound-Guided Carpal Tunnel Release: Preliminary Clinical Results.

Ultrasound-guided carpal tunnel release was performed on 14 patients (18 wrists) using dynamic expansion of the transverse safe zone. Our patient population included able-bodied patients and those with impairments. The first 8 cases (12 wrists) underwent the procedure in an operating room, the remainder in an outpatient setting. No complications occurred, and all patients were able to immediately resume use of their hands without therapy. Improvements in the Quick Form of the Disabilities of the Arm, Shoulder, and Hand Index and Boston Carpal Tunnel Questionnaire at 3 months were comparable to results reported with mini-open and endoscopic release. Our results show that ultrasound-guided carpal tunnel release can be safely and effectively performed in an outpatient setting.

Interrater reliability of electrodiagnosis in neonatal brachial plexopathy.

INTRODUCTION: We investigated interrater reliability of overall assessment of nerve root lesions by electrodiagnostic testing (EDX) in neonatal brachial plexus palsy (NBPP). METHODS: Two blinded, board-certified reviewers retrospectively reviewed de-identified EDX data from 37 infants with NBPP for 2005-2012. Only nerve conduction and electromyography needle data were included. The examiners independently assigned 1 of 4 nerve root lesion categories: (1) pre-ganglionic lesion (avulsion), (2) post-ganglionic lesion (rupture), (3) normal, or (4) "unable to determine." Simple percentage agreement, the Cohen kappa statistic representing interrater reliability for each nerve root (C5-T1), and overall kappa between examiners were evaluated. RESULTS: Interrater reliabilities were substantial to almost perfect for each nerve root except C5. Considering all nerve roots, overall interrater reliability was substantial (kappa = 0.62); simple percentage agreement was 75% (138/185). CONCLUSIONS: Interrater reliability of nerve root assessment by EDX for infants with NBPP was high for C6-T1 root levels, but less reliable for C5 because of technical factors. Muscle Nerve 55: 69-73, 2017.

Imaging Nerve Pathology of the Knee: Magnetic Resonance Imaging and Ultrasound.

Peripheral neuropathies are not uncommon, and the diagnostic evaluation includes a clinical assessment and electrophysiologic studies as well as diagnostic imaging. Magnetic resonance imaging (MRI) and high-resolution ultrasound (HRUS) are of special importance in providing the surgeon with information in the context of nerve trauma, entrapment, and nerve involvement by tumors. Peripheral neuropathy about the knee can occur in the context of associated knee pathology such as trauma, as part of a systemic disease, or as an isolated finding. In this review, we discuss the role of MRI and HRUS in the evaluation of peripheral neuropathy and present imaging examples of peripheral neuropathy involving the knee.

Pilot study of intraoperative ultrasound-guided instrument placement in nerve transection surgery for peripheral nerve pain syndromes.

Surgical transection of sensory nerves in the treatment of intractable neuropathic pain is a commonly performed procedure. At times these cases can be particularly challenging when encountering obese patients, when targeting deeper nerves or those with a variable branching pattern, or in the case of repeat operations. In this case series, the authors describe their experience with ultrasound-guided surgical instrument placement during transection of a saphenous nerve in the region of prior vascular surgery in 1 patient and in the lateral femoral cutaneous nerve in 2 obese patients. The authors also describe this novel technique and provide pilot data that suggests ultrasound-assisted surgery may allow for complex cases to be completed in an expedited fashion through smaller incisions.

Thrombolytic-Enhanced Extracorporeal Cardiopulmonary Resuscitation After Prolonged Cardiac Arrest.

OBJECTIVE: To investigate the effects of the combination of extracorporeal cardiopulmonary resuscitation and thrombolytic therapy on the recovery of vital organ function after prolonged cardiac arrest. DESIGN: Laboratory investigation. SETTING: University laboratory. SUBJECTS: Pigs. INTERVENTIONS: Animals underwent 30-minute untreated ventricular fibrillation cardiac arrest followed by extracorporeal cardiopulmonary resuscitation for 6 hours. Animals were allocated into two experimental groups: t-extracorporeal cardiopulmonary resuscitation (t-ECPR) group, which received streptokinase 1 million units, and control extracorporeal cardiopulmonary resuscitation (c-ECPR), which did not receive streptokinase. In both groups, the resuscitation protocol included the following physiologic targets: mean arterial pressure greater than 70 mm Hg, cerebral perfusion pressure greater than 50 mm Hg, PaO2 150 ± 50 torr (20 ± 7 kPa), PaCO2 40 ± 5 torr (5 ± 1 kPa), and core temperature 33°C ± 1°C. Defibrillation was attempted after 30 minutes of extracorporeal cardiopulmonary resuscitation. MEASUREMENTS AND MAIN RESULTS: A cardiac resuscitability score was assessed on the basis of success of defibrillation, return of spontaneous heart beat, weanability from extracorporeal cardiopulmonary resuscitation, and left ventricular systolic function after weaning. The addition of thrombolytic to extracorporeal cardiopulmonary resuscitation significantly improved cardiac resuscitability (3.7 ± 1.6 in t-ECPR vs 1.0 ± 1.5 in c-ECPR). Arterial lactate clearance was higher in t-ECPR than in c-ECPR (40% ± 15% vs 18% ± 21%). At the end of the experiment, the intracranial pressure was significantly higher in c-ECPR than in t-ECPR. Recovery of brain electrical activity, as assessed by quantitative analysis of electroencephalogram signal, and ischemic neuronal injury on histopathologic examination did not differ between groups. Animals in t-ECPR group did not have increased bleeding complications, including intracerebral hemorrhages. CONCLUSIONS: In a porcine model of prolonged cardiac arrest, t-ECPR improved cardiac resuscitability and reduced brain edema, without increasing bleeding complications. However, early electroencephalogram recovery and ischemic neuronal injury were not improved.

The current role of diagnostic imaging in the preoperative workup for refractory neonatal brachial plexus palsy.

INTRODUCTION: Despite recent improvements in perinatal care, the incidence of neonatal brachial plexus palsy (NBPP) remains relatively common. CT myelography is currently considered to be the optimal imaging modality for evaluating nerve root integrity. Recent improvements in MRI techniques have made it an attractive alternative to evaluate nerve root avulsions (preganglionic injuries). AIM: We demonstrate the utility of MRI for the evaluation of normal and avulsed spinal nerve roots. We also show the utility of ultrasound in providing useful preoperative evaluation of the postganglionic brachial plexus in patients with NBPP.

Sonography of Common Peripheral Nerve Disorders With Clinical Correlation.

Sonography is now considered an effective method to evaluate peripheral nerves. Low cost, high resolution, the ability to image an entire limb in a short time, and dynamic assessment are several of the positive attributes of sonography. This article will review the normal appearance of peripheral nerves as shown with sonography. In addition, the most common applications for sonography of the peripheral nerves will be reviewed, which include entrapment neuropathies, intraneural ganglion cyst, nerve trauma, and peripheral nerve sheath tumors. Clinical information related to nerve disorders is also included, as it provides valuable information that can be obtained during sonographic examinations, increasing diagnostic accuracy.

Utility of ultrasound in noninvasive preoperative workup of neonatal brachial plexus palsy.

BACKGROUND: Ultrasound has been utilized in the evaluation of compressive and traumatic peripheral nerve pathology. OBJECTIVE: To determine whether US can provide comprehensive evaluation of the post-ganglionic brachial plexus in the setting of neonatal brachial plexus palsy and whether this information can be used to guide preoperative nerve reconstruction strategies. MATERIALS AND METHODS: In this retrospective cohort study, preoperative brachial plexus ultrasonography was performed in 52 children with neonatal brachial plexus palsy who were being considered for surgery. The 33 children who had surgery compose the patient cohort. The presence and location of post-ganglionic neuromas were evaluated by US and compared to the surgical findings. US evaluation of shoulder muscle atrophy was conducted as an indirect way to assess the integrity of nerves. Finally, we correlated glenohumeral joint laxity to surgical and clinical management. RESULTS: Ultrasound correctly identified 21 of 25 cases of upper trunk and middle trunk neuroma involvement (84% sensitivity for each). It was 68% sensitive and 40% specific in detection of lower trunk involvement. US identified shoulder muscle atrophy in 11 of 21 children evaluated; 8 of these 11 went on to nerve transfer procedures based upon the imaging findings. US identified 3 cases of shoulder joint laxity of the 13 children evaluated. All 3 cases were referred for orthopedic evaluation, with 1 child undergoing shoulder surgery and another requiring casting. CONCLUSION: Ultrasound can provide useful preoperative evaluation of the post-ganglionic brachial plexus in children with neonatal brachial plexus palsy.

Persistence of Neonatal Brachial Plexus Palsy Associated with Maternally Reported Route of Delivery: Review of 387 Cases.

Objective The factors associated with persistent neonatal brachial plexus palsy (PNBPP) are unknown. Our objectives are to compare PNBPP at 1 and 2 years in children delivered via vaginal delivery (VD) versus cesarean delivery (CD) and in children delivered via VD with or without reported shoulder dystocia (SD). Study Design Retrospective cohort of children diagnosed with neonatal brachial plexus palsy (NBPP). Maternally reported delivery history and presence of SD were recorded with Student t-test, chi-square test, and odds ratio (OR) with 95% confidence intervals (CI) calculated for comparisons. Results Of 387 cases of NBPP, 8% (30) delivered via CD. Rates of PNBPP were higher in the VD group at 1 and 2 years (60% of CD and 85% of VD; OR, 0.26; 95% CI, 0.11-0.62 at 1 year; 33% of CD and 73% of VD; OR, 0.15; 95% CI, 0.05-0.39 at 2 years). There was no difference in PNBPP in women with VD with or without maternally reported SD (87 vs. 85%, p = 0.68 at 1 year; 64 vs. 61%, p = 0.61 at 2 years). Conclusion PNBPP is possible with CD, and there is no difference in PNBPP in VD with or without maternally reported SD. A prospective study is warranted to ascertain associative factors.

Retroperitoneal course of iliohypogastric, ilioinguinal, and genitofemoral nerves: A study to improve identification and excision during triple neurectomy.

Triple neurectomy of the iliohypogastric (IHN), ilioinguinal (IIN), and genitofemoral (GFN) nerves is an available treatment option for chronic groin pain when conservative measures are ineffective. This research study attempted to define the variability of IHN, IIN, and GFN by categorizing variation and establishing a relationship to clinically significant landmarks. 22 cadavers (43 specimens) were dissected. Age, gender, ethnicity, BMI, and pertinent medical history were recorded for each specimen. Nerve emergence, insertion, and split points were measured in relation to clinically significant landmarks. Retroperitoneal trajectories of IHN, IIN, and GFN were analyzed and categorized based on nerve branching patterns. IIN and IHN had three branching patterns - type A (47%) in which the IIH and IIN exit as separate branches; type B (26%) in which the IIH and IIN exit as a single bundle and split; and type C (28%) in which the IIH and IIN exit and do not split. The GFN had three branching patterns--type 1 (50%) in which the GFN exited from the psoas major and then split into the genital and femoral branches; type 2 (30%) in which the GFN exited and did not split; and type 3 (20%) in which the GFN exited the psoas major already split into the genital and femoral branches. Variations in the IHN, IIN, and GFN nerves outlined in this study will provide surgeons with clinically useful information aiding in successful and efficient localization of these nerves during retroperitoneal procedures, including laparoscopic triple neurectomy.

Home-based movement therapy in neonatal brachial plexus palsy: A case study.

STUDY DESIGN: Case report. INTRODUCTION: The value of movement-based therapy in peripheral nerve injury conditions such as neonatal brachial plexus palsy (NBPP) is unclear. PURPOSE OF THE STUDY: To determine the effectiveness of a home-based movement therapy program in a 17 year old female patient with a right NBPP pan-plexopathy. METHODS: Home training consisted of arm reaching and object manipulation tasks using devices which recorded performance. Training occurred for 1 h/day, 5 days/week for 6 weeks with periodic webcam supervision. Pre- and post clinical, functional and kinematic assessments were performed in a laboratory setting. RESULTS: Following training, shoulder flexion and elbow extension active range of motion increased by 13° and 9°, respectively, and functional ability also improved. Reach movement duration decreased significantly with a concomitant improvement in movement coordination. CONCLUSIONS: These results demonstrate that movement therapy has the potential to improve motor function in NBPP years after the initial insult. LEVEL OF EVIDENCE: 4.

Predictors of functional outcomes after simple decompression for ulnar neuropathy at the elbow: a multicenter study by the SUN study group.

OBJECTIVE: To identify predictors of surgical outcome for ulnar neuropathy at the elbow (UNE). DESIGN: Prospective cohort followed for 1 year. SETTING: Clinics. PARTICIPANTS: Patients diagnosed with UNE (N=55). INTERVENTION: All subjects had simple decompression surgery. MAIN OUTCOME MEASURES: The primary outcome measure was patient-reported outcomes, such as overall hand function through the Michigan Hand Outcomes Questionnaire (MHQ). Predictors included age, duration of symptoms, disease severity, and motor conduction velocity across the elbow. RESULTS: Multiple regression models with change in the overall MHQ score as the dependent variable showed that at 3 months postoperative time, patients with <3 months duration of symptoms showed 12 points (95% confidence interval [CI], 0.9-23.5) greater improvement in MHQ scores than those with ≥3 months symptom duration. Less than 3 months of symptoms was again associated with 13 points (95% CI, 2.9-24) greater improvement in MHQ scores at 6 months postoperative, but it was no longer associated with better outcomes at 12 months. A worse baseline MHQ score was associated with significant improvement in MHQ scores at 3 months (coefficient, -0.38; 95% CI, -.67 to -.09), and baseline MHQ score was the only significant predictor of 12 month MHQ scores (coefficient, -.40; 95% CI, -.79 to -.01). CONCLUSIONS: Subjects with <3 months of symptoms and worse baseline MHQ scores showed significantly greater improvement in functional outcomes as reported by the MHQ. However, duration of symptoms was only predictive at 3 or 6 months because most patients recovered within 3 to 6 months after surgery.

G. Carl Huber (1865-1934): A Michigan Pioneer in Peripheral Nerve Injury and Regeneration.

The treatment of peripheral nerve injuries has seen tremendous innovations over the past century. Dr Gotthelf Carl Huber, an American immigrant and early experimental pioneer in the field of peripheral nerve injury, created a foundation of scientific knowledge for these advancements. At the beginning of his career, Huber published novel work in peripheral nerve injury, supporting the concept of Wallerian degeneration and demonstrating the use of nerve grafting for repair. As his scientific career evolved into other research areas at the University of Michigan, Huber's impact extended far beyond just the study of peripheral nerve injury. Because of the external forces of the First World War, Dr Huber's focus returned to translational projects concentrated on the treatment of neuromas and war time peripheral nerve injuries. Huber's scientific impact in the field of peripheral nerve injury and repair came as a result of his incredible work ethic, mentorship, and tremendous leadership qualities; through this, his work still influences clinical practice today, a century later.

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

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

Understanding quality of life and patient expectations among adolescents with neonatal brachial plexus palsy: a qualitative and quantitative pilot study.

PURPOSE: To explore the quality of life (QOL) and patient expectations among adolescents with neonatal brachial plexus palsy (NBPP)and their parents using qualitative and quantitative approaches. METHODS: A total of 18 adolescents (10-17 y) with residual NBPP impairment and their parents under went separate 1-hour tape-recorded semistructured interviews. We also collected quantitative physical examination measures and patient-rated outcome scores, specifically the Pediatric Outcomes Data Collection Instrument and the Child Health Questionnaire, to quantify the severity of each adolescent's functional deficit and increase our understanding of QOL and patient expectations. RESULTS: Through qualitative analysis, we identified several patient- and system-dependent factors contributing to QOL, such as social impact and peer acceptance, emotional adjustment,aesthetic concerns and body image, functional limitations, physical and occupational therapy, finances, pain, and family dynamics. Despite residual impairment, most adolescents and their parents reported a good overall QOL according to quantitative outcome measures. Our study results showed that functional and aesthetic factors were responsible for most observed differences in QOL among NBPP adolescents. We also found that the Pediatric Outcomes Data Collection Instrument might be more sensitive than the Child Health Questionnaire in assessing patient expectations and QOL among this patient population. CONCLUSIONS: Understanding patient expectations and QOL in NBPP adolescents is essential for medical decision making and advancing care. Physical examination measurements alone may not be sufficient for measuring outcome, and knowledge regarding environmental factors and family dynamics is important for clinicians to consider when counseling families of children with NBPP and improving overall outcome. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

Quantifying real-world upper limb activity via patient-initiated spontaneous movement in neonatal brachial plexus palsy.

BACKGROUND: Neonatal brachial plexus palsy (NBPP) results in muscle weakness and impaired somatosensory function of the arm. Current functional assessment is primarily based on clinician-elicited measurements including muscle strength and range of motion. To what extent these measures are representative of real-world arm movement is unclear. OBJECTIVE: To determine the feasibility of using body-worn accelerometers to remotely assess arm movements in children with NBPP. DESIGN: Prospective criterion validity study of accelerometry versus clinician assessment. SETTING: Academic medical center. PARTICIPANTS: Nine adolescents with NBPP and nine age- and gender-matched control adolescents participated in the study. All were enrolled in school and participated in community activities. INTERVENTIONS: Not applicable. METHODS: Standard clinician-elicited measurements were collected. For assessing spontaneous arm movements, participants wore activity monitors during all waking hours for 7 days. Results were expressed as ratios of affected to unaffected arm motion for duration and magnitude and correlated with traditional clinic-based assessments. Spearman correlations were used to determine relationships between accelerometry results and traditional assessments. A p value <.05 was considered statistically significant. MAIN OUTCOME MEASUREMENTS: Accelerometry measurements of arm motion and traditional clinical assessments. RESULTS: Compared to control ratios, duration of arm movement and magnitude ratios were reduced in the NBPP group, particularly for arm magnitude due to reduced affected arm movement and an increase in unaffected arm movement. Ratios were highly correlated with shoulder function and, to a lesser extent, with elbow function. CONCLUSION: Real-world arm use is an appropriate outcome measure that reflects functional recovery. This study demonstrates the feasibility of wearable technology to quantify duration and intensity of spontaneous arm movement in children with NBPP. Accelerometry also allows for the association between traditional clinician-elicited assessment measures and spontaneous arm movements, demonstrating the importance of the shoulder as a focus of treatment in NBPP.