Shear wave elastography evaluation of brachial plexus in multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is a chronic neuroinflammatory disease characterized by inflammation involving the peripheral nerves. Shear wave elastography (SWE) is potentially a method of choice for detecting peripheral nerve involvement. PURPOSE: To compare the degree of thickening and nerve elasticity of brachial plexus (BP) nerve roots and evaluate the usefulness of sonoelastography in patients with clinically diagnosed MS without brachial plexopathy. MATERIAL AND METHODS: Thirty-two patients with MS and 32 controls were included in the study. Bilateral C5, C6, and C7 mean nerve root diameters, and mean elasticity values in kiloPascal (kPa) were measured in the patient and control groups. The relationship between the age, height, and weight values and nerve diameter-elasticity values of the patient and control groups was compared. RESULTS: The elasticity values of the C5 and C6 nerve roots were increased, and the nerve root thickness was decreased in the MS group compared to that in the control (P < 0.05). There was no difference between the C7 mean nerve root elasticity (kPa) and diameter measurements in the patient and control groups (P > 0.05). CONCLUSION: Our study showed an increase in the BP nerve root elasticity values (kPa) in patients with MS compared to that of the control group and a decrease in diameter values thought to be related to the possible chronic atrophic process. The results are consistent with the demyelinating process of the peripheral nervous system (PNS) due to MS.

Long-Term Suppression of c-Jun and nNOS Preserves Ultrastructural Features of Lower Motor Neurons and Forelimb Function after Brachial Plexus Roots Avulsion.

Brachial plexus root avulsions cause debilitating upper limb paralysis. Short-term neuroprotective treatments have reported preservation of motor neurons and function in model animals while reports of long-term benefits of such treatments are scarce, especially the morphological sequelae. This morphological study investigated the long-term suppression of c-Jun- and neuronal nitric oxide synthase (nNOS) (neuroprotective treatments for one month) on the motor neuron survival, ultrastructural features of lower motor neurons, and forelimb function at six months after brachial plexus roots avulsion. Neuroprotective treatments reduced oxidative stress and preserved ventral horn motor neurons at the end of the 28-day treatment period relative to vehicle treated ones. Motor neuron sparing was associated with suppression of c-Jun, nNOS, and pro-apoptotic proteins Bim and caspases at this time point. Following 6 months of survival, neutral red staining revealed a significant loss of most of the motor neurons and ventral horn atrophy in the avulsed C6, 7, and 8 cervical segments among the vehicle-treated rats (n = 4). However, rats that received neuroprotective treatments c-Jun JNK inhibitor, SP600125 (n = 4) and a selective inhibitor of nNOS, 7-nitroindazole (n = 4), retained over half of their motor neurons in the ipsilateral avulsed side compared. Myelinated axons in the avulsed ventral horns of vehicle-treated rats were smaller but numerous compared to the intact contralateral ventral horns or neuroprotective-treated groups. In the neuroprotective treatment groups, there was the preservation of myelin thickness around large-caliber axons. Ultrastructural evaluation also confirmed the preservation of organelles including mitochondria and synapses in the two groups that received neuroprotective treatments compared with vehicle controls. Also, forelimb functional evaluation demonstrated that neuroprotective treatments improved functional abilities in the rats. In conclusion, neuroprotective treatments aimed at suppressing degenerative c-Jun and nNOS attenuated apoptosis, provided long-term preservation of motor neurons, their organelles, ventral horn size, and forelimb function.

Roles of preoperative and early postoperative electrodiagnosis in brachial plexus injury patients undergoing nerve transfer operations: retrospective feasibility study.

OBJECTIVE: The purpose of this retrospective observational study was to assess the feasibility of electrodiagnostic parameters, perioperatively, and to discover optimal values as prognostic factors for patients with brachial plexus injury undergoing nerve transfer operations. METHODS: We retrospectively reviewed the records of 11 patients who underwent nerve transfer surgery. The patients underwent perioperative electrodiagnosis (EDX) before and approximately 6 months after surgery. We evaluated the compound muscle action potential (CMAP) ratio, motor unit recruitment, and their interval changes. To evaluate motor strength, we used the Medical Research Council (MRC) grade, 6 and 12 months after surgery. We evaluated the relationships between improved CMAP ratio, and motor unit recruitment and MRC grade changes 6 and 12 months postoperatively. RESULTS: All parameters increased significantly after surgery. The CMAP ratio improvement 6 months after surgery correlated with the MRC grade change from baseline to 12 months, with a correlation coefficient of 0.813. CONCLUSION: EDX parameters improved significantly postoperatively, and the CMAP ratio improvement 6 months after surgery correlated with the clinical outcomes at 1 year. The results of perioperative EDX might help establish long-term treatment plans for patients who undergo nerve transfer surgery.

The Relationship between Trunk Control and Upper Extremity Function in Children with Obstetric Brachial Plexus Palsy.

PURPOSE: This study aimed to assess sitting skills and trunk control in children with obstetric brachial plexus palsy (OBPP) and investigate the effect of these skills on upper extremity function. METHODS: A total of 106 children with OBPP aged 10-18 months were included in this study. Injury severity was determined with Narakas Classification. The Gross Motor Function Measurement Sitting Sub-scale was used to assess sitting skills, while the Sitting Assessment Scale was used to evaluate the trunk control. The upper extremity functions were assessed with using the Active Movement Scale and the Modified Mallet Score. RESULTS: As the severity of injury increased, sitting skills and trunk control values decreased (p = .0001). In addition, upper extremity function decreased with the decreasing sitting skills and trunk control (p = .0001). CONCLUSION: Rehabilitation approaches should involve approaches that aim to increase trunk control in addition to programs targeting the extremity function in children with OBPP.

The Neurokinin-1 Receptor is Expressed with Gastrin-Releasing Peptide Receptor in Spinal Interneurons and Modulates Itch.

The neurokinin-1 receptor (NK1R; encoded by Tacr1) is expressed in spinal dorsal horn neurons and has been suggested to mediate itch in rodents. However, previous studies relied heavily on neurotoxic ablation of NK1R spinal neurons, which limited further dissection of their function in spinal itch circuitry. To address this limitation, we leveraged a newly developed Tacr1CreER mouse line to characterize the role of NK1R spinal neurons in itch. We show that pharmacological activation of spinal NK1R and chemogenetic activation of Tacr1CreER spinal neurons increases itch behavior in male and female mice, whereas pharmacological inhibition of spinal NK1R suppresses itch behavior. We use fluorescence in situ hybridization (FISH) to characterize the endogenous expression of Tacr1 throughout the superficial and deeper dorsal horn (DDH), as well as the lateral spinal nucleus (LSN), of mouse and human spinal cord. Retrograde labeling studies in mice from the parabrachial nucleus (PBN) show that less than 20% of superficial Tacr1CreER dorsal horn neurons are spinal projection neurons, and thus the majority of Tacr1CreER are local interneurons. We then use a combination of in situ hybridization and ex vivo two-photon Ca2+ imaging of the mouse spinal cord to establish that NK1R and the gastrin-releasing peptide receptor (GRPR) are coexpressed within a subpopulation of excitatory superficial dorsal horn (SDH) neurons. These findings are the first to suggest a role for NK1R interneurons in itch and extend our understanding of the complexities of spinal itch circuitry.SIGNIFICANCE STATEMENT The spinal cord is a critical hub for processing somatosensory input, yet which spinal neurons process itch input and how itch signals are encoded within the spinal cord is not fully understood. We demonstrate neurokinin-1 receptor (NK1R) spinal neurons mediate itch behavior in mice and that the majority of NK1R spinal neurons are local interneurons. These NK1R neurons comprise a subset of gastrin-releasing peptide receptor (GRPR) interneurons and are thus positioned at the center of spinal itch transmission. We show NK1R mRNA expression in human spinal cord, underscoring the translational relevance of our findings in mice. This work is the first to suggest a role for NK1R interneurons in itch and extends our understanding of the complexities of spinal itch circuitry.

Perineural spread to the brachial plexus: a focused review of proposed mechanisms and described pathologies.

BACKGROUND: Perineural spread (PNS) is an emerging mechanism for progressive, non-traumatic brachial plexopathy. We aim to summarize the pathologies (tumor and infection) shown to have spread along or to the brachial plexus, and identify the proposed mechanisms of perineural spread. METHODS: A focused review of the literature was performed pertaining to pathologies with identified perineural spread to the brachial plexus. RESULTS: We summarized pathologies currently reported to have PNS in the brachial plexus and offer a structure for understanding and describing these pathologies with respect to their interaction with the peripheral nervous system. CONCLUSIONS: Perineural spread is an underrepresented entity in the literature, especially regarding the brachial plexus. It can occur via a primary or secondary mechanism based on the anatomy, and understanding this mechanism helps to support biopsies of sacrificial nerve contributions, leading to more effective and timely treatment plans for patients.

Acute Flaccid Myelitis With Neuroradiological Finding of Brachial Plexus Swelling.

BACKGROUND: Acute flaccid myelitis is a recently defined clinically distinct syndrome of polio-like acute flaccid paralysis. Acute flaccid myelitis cases show characteristic neuroradiological features of longitudinal spinal cord lesions with predominant gray matter involvement. Current evidence suggests injury to the anterior horn neurons as the underlying mechanism. METHODS: We describe three patients with acute flaccid myelitis who developed flaccid upper limb weakness with diminished deep tendon reflexes after prodromal fever. Spinal magnetic resonance imaging (MRI) (axial and sagittal T1- and T2-weighted sequences) and brachial plexus MRI (coronal short tau inversion recovery sequence) at the acute stage were performed. RESULTS: Spinal MRI showed extensive longitudinal lesion in the spinal cord with predominant gray matter involvement. We were able to demonstrate concurrent swelling and hyperintensity in the brachial plexus in all the three patients at the acute stage. CONCLUSION: The coexisting signal intensities suggest an extension of acute flaccid myelitis pathology to the brachial plexus, highlighting the possible peripheral nerve involvement in acute flaccid myelitis.

Brachial plexus birth injuries and the association between pre-procedure and post-procedure pediatric outcomes data collection instrument scores and narakas classification.

BACKGROUND: The brachial plexus is a network of nerves exiting the spinal cord through the fifth, sixth, seventh, and eighth cervical nerves (C5-C8) as well as the first thoracic nerve (T1) to conduct signals for motion and sensation throughout the arm. Brachial plexus birth injuries (BPBI) occur in 1.5 per 1,000 live births. The purpose of this study was to determine the perceived change in musculoskeletal health-related quality of life of brachial plexus patients utilizing the Pediatric Outcomes Data Collection Instrument (PODCI). PODCI scores were examined along with the patient's procedure history (surgical or Botulinum Toxin), extent of involvement and demographics. PATIENTS: A total of 81 patients from two to eighteen years of age from nine different states met the inclusion criteria of having a pre-procedure and post-procedure PODCI score along with a Narakas score from 2002-2017. These patients were seen at the Brachial Plexus Center, which is an interdisciplinary clinic at a large academic medical centerMETHODS: This retrospective study utilized PODCI data collected annually during their regular brachial plexus clinic visits. Upper extremity (UE) and global functioning (GFx) scores pre- and post-procedure were stratified by Narakas Classification. Data were analyzed using paired t-test and ANOVA testing. RESULTS: Patients with a Brachial Plexus Birth Injury (BPBI) had lower PODCI scores for UE and GFx when compared with the pediatric normative scores for age-matched healthy children. Scores in both UE and GFx domains were higher after procedure in the groups of Narakas I and IV. There was significant correlation between UE and GFx scores and documented first PODCI score (2 years of age) and age at intervention (5 years of age). CONCLUSION: Procedures increased the perceived quality of life for children with a BPBI and increased their overall PODCI scores for both UE and GFx.

Optimal reference electrode placement for accessory and axillary nerve conduction studies.

BACKGROUND: Various techniques are described for proximal motor nerve conduction studies (NCSs). We investigated alternative reference electrode (E2) locations for accessory and axillary NCSs. METHODS: Multi-channel recordings were made from trapezius or deltoid referred to different sites, and from those sites referred to a remote electrode. Responses were compared using grouped statistics, and correlation analysis. RESULTS: For accessory NCSs, all belly:E2 montages showed comparable responses but axillary NCSs were more variable. Low amplitude contamination was seen at the sternum and contralateral acromion but greater distortion using other potential E2 sites. In both accessory and axillary studies, the ipsilateral acromion showed moderate activity, which correlated with the belly:remote response. CONCLUSIONS: Variation in E2 electrode sites may significantly distort the measured compound muscle action potential (CMAP). For accessory and axillary NCS, a sternal reference has favorable characteristics. Other sites, such as ipsilateral acromion or deltoid insertion, may not yield a representative CMAP.

Low interrater reliability of brachial plexus MRI in chronic inflammatory neuropathies.

INTRODUCTION: Magnetic resonance imaging of the brachial plexus shows nerve thickening in approximately half of the patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and multifocal motor neuropathy (MMN). The reliability of qualitative evaluation of brachial plexus MRI has not been studied previously. METHODS: We performed an interrater study in a retrospective cohort of 19 patients with CIDP, 17 patients with MMN, and 14 controls. The objective was to assess interrater variability between radiologists by using a predefined scoring system that allowed the distinction of no, possible, or definite nerve thickening. RESULTS: Raters agreed in 26 of 50 (52%) brachial plexus images; κ-coefficient was 0.30 (SE 0.08, 95% confidence interval 0.14-0.46, P < .0005). DISCUSSION: Our results provide evidence that interrater reliability of qualitative evaluation of brachial plexus MRI is low. Objective criteria for abnormality are required to optimize the diagnostic value of MRI for inflammatory neuropathies.

Anatomic Variation of the Phrenic Nerve and Brachial Plexus Encountered during 100 Supraclavicular Decompressions for Neurogenic Thoracic Outlet Syndrome with Associated Postoperative Neurologic Complications.

BACKGROUND: The objective of this study was to characterize phrenic nerve and brachial plexus variation encountered during supraclavicular decompression for neurogenic thoracic outlet syndrome and to identify associated postoperative neurologic complications. METHODS: A multicenter retrospective review was performed to evaluate anatomic variation of the phrenic nerve and brachial plexus from November 2010 to July 2018. After initial characterization, the following two groups were identified: variant anatomy (VA) group and standard anatomy (SA) group. Complications were analyzed and compared between the two groups. RESULTS: In total, 105 patients were identified, and 100 patients met inclusion criteria. Any anatomic variation of the standard course or configuration of the phrenic nerve and/or brachial plexus was encountered in 47 (47%) patients. Phrenic nerve anatomic variations were identified in 28 (28%) patients. These included 9 duplicated nerves, 6 lateral accessory nerves, 8 medial displacement, and 5 lateral displacement. Brachial plexus anatomic variation was found in 34 (34%) patients. The most common variant configuration of a fused middle and inferior trunk was identified in 25 (25%) patients. Combined phrenic nerve and brachial plexus anatomic variation was demonstrated in 15 (15%) patients. The VA and SA groups consisted of 47 and 53 patients, respectively. Transient phrenic nerve injury with postoperative elevation of the ipsilateral hemidiaphragm was documented in 3 (6.4%) patients in the VA group and 6 (11.3%) patients in the SA group (P = 0.49). Permanent phrenic nerve injury was identified in 1 (2.1%) patient in the VA group (P = 0.47) and none in the SA group. Transient brachial plexopathy was encountered in 1 (1.9%) patient in the SA group (P = 1.0) with full recovery to normal function. CONCLUSIONS: Anatomic variability of the phrenic nerve and brachial plexus are encountered more frequently than previously reported. While the incidence of nerve injury is low, surgeons operating within the thoracic aperture should be familiar with variant anatomy to reduce postoperative complications.

Pressure algometry and palpation of the upper limb peripheral nervous system in subjects with hand osteoarthritis are repeatable and suggest central changes.

STUDY DESIGN: Case-control study. INTRODUCTION: A subset of patients with hand osteoarthritis (OA) shows evidence of central pain phenotypes. PURPOSE OF THE STUDY: To examine whether differences exist in experimental pain responses in the affected and nonaffected sides of patients with unilateral hand OA. To investigate the test-retest reliability of pressure algometry and manual digital palpation in patients with unilateral hand OA. METHODS: The hand OA group consisted of 20 patients, and the control group consisted of 20 healthy subjects. Pressure pain threshold (PPT) measurements were made 2 times, consisting of 3 repeat trials, each using computerized algometry and manual digital palpation. Grip and key strength (dynamometer), pain (visual analog scale), and function (Disabilities of the Arm, Shoulder and Hand [short version]) were also measured. The 2-way analysis of variance was conducted to determine the differences between sides and groups. Intraclass correlation coefficient (ICC) and standard error of measurement were calculated. RESULTS: Patients with hand OA had decreased PPTs over the thumb carpometacarpal joint as well as radial and median nerves compared with controls (all P < .01). No significant group effect by side interaction was detected for any measure. The minimal detectable change values needed to detect change in subjects with hand OA were C5-C6 joint (0.3-0.5 kg/cm2), carpometacarpal joint (0.3-0.5 kg/cm2), hamate bone (0.2-0.4 kg/cm2), radial nerve (0.2-0.8 kg/cm2), median nerve (0.3-0.6 kg/cm2), and ulnar nerve (0.2-0.4 kg/cm2) for PPT. Test-retest reliability was calculated for both hands of participants with OA (ICC, 0.98-0.99) and healthy participants (ICC, 0.74-0.99). DISCUSSION: Although pressure algometry and manual digital palpation are techniques already used in previous studies and have been shown to be reproducible and moderately reliable for joint palpation, this current study suggests that pressure algometry and manual digital palpation could also be reliable methods of determining nerve sensitivity of the radial, ulnar and median nerves in subjects with hand OA. CONCLUSIONS: Hyperalgesia in patients with hand OA might be associated with clinical measures, and bilateral signs in unilateral OA could suggest central changes.

Comparison of MRI and motor evoked potential with triple stimulation technique for the detection of brachial plexus abnormalities in multifocal motor neuropathy.

BACKGROUND: Conduction blocks (CB) are the diagnostic hallmark of multifocal motor neuropathy (MMN). Conventional nerve conduction studies cannot detect CB above Erb's point. Our purpose was to compare the performance of the motor evoked potential with triple stimulation technique (MEP-TST) and MRI in the detection of abnormalities of the brachial plexus. METHODS: Examinations were performed on 26 patients with MMN (11 definite, 6 probable, 9 possible), of whom 7 had no CB. RESULTS: MEP-TST detected proximal CB in 19/26 patients. Plexus MRI showed T2 hyperintensity in 18/26 patients, with nerve enlargement in 14/18. A combination of both techniques increased the detection rate of brachial plexus abnormalities to 96% of patients (25/26). CONCLUSIONS: MEP-TST and MRI have high sensitivities for detecting brachial plexus abnormalities. A combination of the two techniques increases the detection rate of supportive criteria for the diagnosis of MMN.

What Range of Motion is Achieved 5 Years After External Rotationplasty of the Shoulder in Infants with an Obstetric Brachial Plexus Injury?

BACKGROUND: Obstetric brachial plexus injuries result from traction injuries during delivery, and 30% of these children have persisting functional limitations related to an external rotation deficit of the shoulder. Little is known about the long-term effect of soft-tissue procedures of the shoulder in patients with obstetric brachial plexus injuries. QUESTIONS/PURPOSES: (1) After soft-tissue release for patients with passive external rotation less than 20° and age younger than 2 years and for patients older than 2 years with good external rotation strength, what are the improvements in passive external rotation and abduction arcs at 1 and 5 years? (2) For patients who underwent staged tendon transfer after soft-tissue release, what are the improvements in active external rotation and abduction arcs at 1 and 5 years? (3) For patients with passive external rotation less than 20° and no active external rotation, what are the improvements in active external rotation and abduction arcs at 1 and 5 years? METHODS: This was a retrospective analysis of a longitudinally maintained institutional database. Between 1996 and 2009, 149 children underwent a soft-tissue procedure of the shoulder for an internal rotation contracture. The inclusion criteria were treatment with an internal contracture release and/or tendon transfer, a maximum age of 18 years at the time of surgery, and a minimum follow-up period of 2 years. Six patients were older than 18 years at the time of surgery and 31 children were seen at our clinic until 1 year postoperatively, but because they had good clinical results and lived far away from our center, these children were discharged to physical therapists in their hometown for annual follow-up. Thus, 112 children (59 boys) were available for analysis. Patients with passive external rotation less than 20° and age younger than 2 years and patients older than 2 years with good external rotation strength received soft-tissue release only (n = 37). Of these patients, 17 children did not have adequate active external rotation, and second-stage tendon transfer surgery was performed. For patients with passive external rotation less than 20° with no active external rotation, single-stage contracture release with tendon transfer was performed (n = 68). When no contracture was present (greater than 20° of external rotation) but the patient had an active deficit (n = 7), tendon transfer alone was performed; this group was not analyzed. A functional assessment of the shoulder was performed preoperatively and postoperatively at 6 weeks, 3 months, and annually thereafter and included abduction, external rotation in adduction and abduction, and the Mallet scale. RESULTS: Internal contracture release resulted in an improvement in passive external rotation in adduction and abduction of 29° (95% confidence interval, 21 to 38; p < 0.001) and 17° (95% CI, 10 to 24; p < 0.001) at 1 year of follow-up and 25° (95% CI, 15-35; p < 0.001) and 15° (95% CI, 7 to 24; p = 0.001) at 5 years. Because of insufficient strength of the external rotators after release, 46% of the children (17 of 37) underwent an additional tendon transfer for active external rotation, resulting in an improvement in active external rotation in adduction and abduction at each successive follow-up visit. Patients with staged transfers had improved active function; improvements in active external rotation in adduction and abduction were 49° (95% CI, 28 to 69; p < 0.05) and 45° (95% CI, 11 to 79; p < 0.001) at 1 year of follow-up and 38° (95% CI, 19 to 58; p < 0.05) and 23° (95% CI, -8 to 55; p < 0.001) at 5 years. In patients starting with less than 20° of passive external rotation and no active external rotation, after single-stage contracture release and tendon transfer, active ROM was improved. Active external rotation in adduction and abduction were 75° (95% CI, 66 to 84; p < 0.001) and 50° (95% CI, 43 to 57; p < 0.001) at 1 year of follow-up and 65° (95% CI, 50 to 79; p < 0.001) and 40° (95% CI, 28 to 52; p < 0.001) at 5 years. CONCLUSION: Young children with obstetric brachial plexus injuries who have internal rotation contractures may benefit from soft-tissue release. When active external rotation is lacking, soft-tissue release combined with tendon transfer improved active external rotation in this small series. Future studies on the degree of glenohumeral deformities and functional outcome might give more insight into the level of increase in external rotation. LEVEL OF EVIDENCE: Level III, therapeutic study.

Influence of a nerve injury proximal to the suprascapular nerve on healing of repaired rotator cuff tear.

BACKGROUND: Massive rotator cuff tears have a high rate of re-injury because of severe fatty infiltration. Our data showed that injuries proximal to the suprascapular nerve may be one cause of massive rotator cuff tears. The purpose of this study was to evaluate, using a rat model, how brachial plexus injury associated with a massive rotator cuff tear influences healing of the rotator cuff repair. METHODS: Seventy Sprague-Dawley rats were divided into three groups: rotator cuff tear with BP injury (DT group) (n = 28), rotator cuff tear without brachial plexus injury (T group) (n = 28), and a sham-operated group (n = 14). In the DT group, the rotator cuff tear was made and repaired 4 weeks after brachial plexus ligation. The gross assessment (evaluated the wet weight), biomechanical testing (evaluated the yield stress and the Young's modulus) and histological analyses (using the Bonar scale) were performed at baseline in the sham group, and at 4 and 12 weeks postoperatively in the DT and T groups (n = 7/group/time). RESULTS: Mean wet weight and yield stress were significantly lower in the DT group than in the T group. Additionally, the mean Young's modulus was significantly higher in the DT group than in the T group. Histologically, greater tendon degeneration was observed around the musculotendinous junction in the DT group than in the T group. CONCLUSION: The gross, biomechanical and histological data show that the repaired rotator cuff tendon with brachial plexus injury in rats does not heal as well as a repaired tendon without an accompanying brachial plexus injury. This suggests that more proximal neuropathy is one risk factor for re-tear of a repaired rotator cuff tendon.

Comparison of spinal accessory nerve transfer to supra-scapular nerve vs. shoulder arthrodesis in adults with brachial plexus injury.

BACKGROUND: Restoring shoulder mobility, stability, and strength is a key goal in patients with brachial plexus injuries. Shoulder arthrodesis is chiefly used as an adjunct to, or after failure of, initial direct nerve surgery. The objective of this study was to compare clinical and functional shoulder outcomes after direct nerve transfer vs. shoulder arthrodesis in adults with supra-clavicular brachial plexus injuries. HYPOTHESIS: Shoulder arthrodesis, currently used as a salvage procedure in brachial palsy injuries, deserves to be viewed to a valid alternative to direct nerve transfer. MATERIAL AND METHODS: A retrospective study was conducted in 58 patients with a follow-up of at least 2 years. Among them, 20 were managed by transfer of a spinal accessory nerve fascicle to the supra-scapular nerve and 38 by shoulder arthrodesis. Outcome measures were shoulder range-of-motion, isometric shoulder strength, and the Disabilities of the Arm, Shoulder, and Hand (DASH) score. RESULTS: Mean age at surgery was 24 years and mean follow-up was 46 months (range, 24-156 months). Motion ranges of the shoulder were not significantly different between the two treatment groups. Data variance was significantly greater in the nerve transfer group than in the shoulder arthrodesis group for scapular antepulsion (p=0.0011), abduction (p<0.001), and external rotation (p=0.0066). Strength was significantly greater in the arthrodesis group in all directions of motion. The DASH scores showed no significant between-group differences. CONCLUSIONS: The results of this study conflict with the widely help opinion that nerve transfer to the supra-scapularis nerve produces better clinical outcomes compared to shoulder arthrodesis. Nerve transfer was not better than shoulder arthrodesis in our patients. The data variance heterogeneity suggests poor predictability and reliability of nerve transfer, in contrast to the modest but predictable and uniform results of shoulder arthrodesis. LEVEL OF EVIDENCE: IV, retrospective observational comparative study.

Kinematic profiles during activities of daily living in adults with traumatic brachial plexus injuries.

BACKGROUND: Injuries to the brachial plexus leave individuals with lasting effects in upper extremity motor function, even with successful surgical restoration of elbow flexion. Quantitatively describing independent patient function during activities of daily living utilizing motion analysis could aid in prioritization of secondary surgical targets, as well as serve as an outcome measure. This study explored the upper extremity kinematic profiles during activities of daily living in adults with brachial plexus injury. METHODS: Eight adult participants (4 subjects with brachial plexus injury, 4 healthy controls) completed activities of daily living during one motion capture setting. Trunk, shoulder, and elbow joint minima, maxima, and range of motion were calculated and compared between groups. Kinematic profiles over a motion cycle were compared between groups using statistical parametric mapping. FINDINGS: Subjects with brachial plexus injuries had significantly greater trunk range of motion during feeding and dressing tasks compared to control subjects. This compensatory trunk motion was accompanied by limited shoulder external rotation demonstrated using conventional descriptors and statistical parametric mapping. INTERPRETATION: Significant compensatory trunk motion is required to complete select activities of daily living in subjects with brachial plexus injury. Additionally, restoration of shoulder external rotation would be a beneficial secondary target of surgical restoration of motor function. These aspects should be considered in treatment planning, as they could impact patient outcomes. Combining conventional descriptors of patient motion (e.g. joint minima, maxima, and range of motion) with statistical parametric mapping can provide a rich description of patient compensations and limitations.

Clinical, electrodiagnostic and imaging features of true neurogenic thoracic outlet syndrome: Experience at a tertiary referral center.

OBJECTIVE: True neurogenic thoracic outlet syndrome (TN-TOS) is an extremely rare neuromuscular disease. We report clinical, electrodiagnostic and radiologic features of patients with TN-TOS. METHODS: Retrospective chart review of patients satisfying criteria was done. Nerve conduction study (NCS) and needle electromyography (EMG) of upper extremity were reviewed. Brachial plexus MRI and computed tomography angiography (CTA) were also reviewed. RESULTS: Thirteen TN-TOS patients were identified. The most common neurologic signs were hypesthesia in the medial forearm or ulnar digits and weakness of the abductor pollicis brevis (APB) muscle. In NCS, medial antebrachial cutaneous (MABC) sensory nerve action potential amplitude was decreased in all tested patients. The APB muscle was most commonly involved in EMG. Among radiologic criteria, focal stenosis of subclavian artery in CTA was the most common finding. CONCLUSION: We confirmed that TN-TOS is T1 predominant lower roots/trunk brachial plexopathy with clinical and electrodiagnostic features. Radiologic studies may be used to detect structural abnormalities. SIGNIFICANCE: As MABC NCS showed abnormal results in all tested patients, it should be added to electrodiagnostic study as screening method. If present, structural abnormalities might be confirmed with radiologic studies.

Brachial plexus injury and resting-state fMRI: Need for consensus.

OBJECTIVE: The purpose of the study is to conduct the systematic review of literature available on resting-state functional MRI (fMRI) and brachial plexus injury. METHODS: We reviewed all the literature that are available on PubMed; keywords used were resting state, brachial plexus injury, and functional imaging. The reference papers listed were also reviewed. The research items were restricted to publications in English. Some papers have also incorporated studies such as task-based fMRI and transcranial magnetic stimulation (TMS), but only resting-state studies were included for this review. RESULTS: A total of 13 papers were identified, and only 10 were reviewed based on the criteria. The reviewed papers were further categorized on the basis of whether or not any surgical intervention was done. Seven papers have surgical management such as contralateral cervical 7 (CC7) neurotisation or intercostal nerve (ICN) musculocutaneous nerve (MCN) neurotisation. CONCLUSION: There is conclusive evidence showing that there is cortical reorganisation following brachial plexus injury in both birth and traumatic cases. The changes are restricted to some of the resting-state networks only (default mode network, sensorimotor network, in particular). However, no study till date has focused on a far more longitudinal approach at studying these changes. It will be interesting to see the exact time and effect of these changes.