Shoulder Abduction Strength Research Articles

Exploring frailty: muscle strength, functional capacity, activities of daily living and cognition in adult congenital heart disease

Purpose The study aimed to assess frailty in adults with congenital heart disease (ACHD) and to compare muscle strength, functional capacity, activities of daily living (ADL), and cognition between frail and non-frail ACHD patients. Materials and methods A cross-sectional study design was used. Sixty people with ACHD aged between 18 and 45 years were included. Frailty was determined according to the Fried criteria. Peripheral muscle strength was assessed with a digital dynamometer, functional capacity with the 6-min walk test (6MWT), ADL with the Glittre ADL test, and cognition with the Montreal Cognitive Assessment (MoCA) test. Results Frailty was seen in 38.33% (frail = 23 and non-frail = 37) of the participants. In the frail patients, dominant knee extensor strength (p = 0.002), shoulder abductor strength (p = 0.005), 6MWT distance (p = 0.021), and MoCA score (p = 0.005) were significantly lower than those in the non-frail patients. Glittre ADL test (p = 0.002) was significantly higher in the frail patients. Conclusions Muscle strength, functional capacity, ADL, functional mobility, and cognition were lower in the frail participants with ACHD. Early assessment of frailty in ACHD and planning individualized exercise training programs for frail individuals may be a strategy to reduce the impact of frailty on adverse clinical outcomes.

Upper extremity neuromuscular function can distinguish between individuals with and without glenohumeral labral repair

The purpose of this study was to determine whether common measures of neuromuscular function could distinguish injury status indicated by group membership (glenohumeral labral repair, uninjured controls). 16 individuals with glenohumeral labral repair (24.1 ± 5.0 years, 36.7 ± 33.3 months after surgery) and 14 uninjured controls (23.8 ± 2.7 years) volunteered. We measured mass-normalized shoulder abduction and wrist flexion maximal voluntary isometric contraction torque (Nm/kg), motoneuron pool excitability of the flexor carpi radialis (Hoffmann reflex), corticospinal excitability of the upper trapezius, middle deltoid, and flexor carpi radialis (active motor threshold [%]) bilaterally. Receiver operator characteristic curve analyses were performed to determine if each outcome could distinguish injury status along with their outcome thresholds. Binary logistic regression was used to determine the accuracy of classification for each outcome. Our results suggest shoulder abduction torque symmetry (≤95.5 %) and corticospinal excitability for the upper trapezius (≥41.0 %) demonstrated excellent diagnostic utility. Shoulder abduction torque (≤0.71 Nm/kg) and motoneuron pool excitability (≤0.23) demonstrated acceptable diagnostic utility. Shoulder abduction torque symmetry alone was the strongest indicator, and classified injury status with 90.0 % accuracy (p < 0.01). Overall, symmetric shoulder abduction strength most accurately distinguished individuals’ injury status, suggesting the utility of bilateral assessment in this population.

The Lycra arm sleeve for treatment of glenohumeral subluxation in people with sub-acute stroke: a randomized controlled (RC) feasibility study

ABSTRACT Background A Lycra arm sleeve has the potential to reduce glenohumeral subluxation (GHS) in people with stroke (PwS). Aims were (1) to provide feasibility data to inform a future fully powered randomized controlled trial, (2) to understand whether patients would be willing to be randomized, (3) to measure changes in GHS at 3 months after wearing the sleeve when compared to not wearing the sleeve. Method PwS ≥18 years with ≤3/5 shoulder abduction strength and able to give informed consent were recruited. The feasibility data on recruitment, screening, and retention rate at 12 weeks were collected. Participants were asked if they would be happy to be randomized into one of the two groups. The immediate group received the Lycra sleeve on recruitment and wore for up to 10 hours/day for 3 months. The delayed group received the sleeve after follow-up assessment at 3 months. GHS was assessed using diagnostic ultrasound method. Results Over one year, 257 patients were screened, 34 patients were eligible, and 31 (91%) were recruited. Retention at 3 months was 27 (87%). Of those eligible, all found randomization to be acceptable. In the immediate group, GHS showed reduction from 2.6 ± 0.7 cm (95% CI 2.0–3.1 cm) at baseline to 2.2 ± 0.4 cm (CI 2.0–2.5 cm) at 12 weeks. In the delayed group, mean GHS remained unchanged over 3 months period (2.3 ± 0.5 cm, CI 1.9–2.7 cm). Conclusion Recruitment was harder than anticipated, but there was high retention demonstrating feasible methodology. There is some indication of a clinical effect of Lycra sleeve on GHS early after stroke.

Insights into the Medial Pectoral Nerve Transfer for Shoulder Abduction in Brachial Plexus Injuries: A Retrospective Case Series Analysis

Treatment priority in C5, C6, and C7 brachial plexus root avulsion is the recovery of shoulder function through reinnervation of shoulder muscles. The medial pectoral nerve is a potential donor for axillary nerve transfer, but outcomes are sparsely reported. This study reports the results of medial pectoral nerve transfer to the axillary nerve. We conducted a retrospective analysis of 12 patients with traumatic brachial plexus injury (C5, C6, and C7 root avulsion) who underwent medial pectoral nerve transfer to the axillary nerve. Sociodemographic and clinical characteristics, including electromyography findings, were documented. We assessed postoperative shoulder abduction strength and range of motion. Statistical analyses compared presurgery and postsurgery outcomes and contrasted our results with those from a study using spinal accessory nerve transfer to the suprascapular nerve. Postsurgery, the mean shoulder abduction range of motion was 65.45°, with a median strength of M2. Significant improvement was noted compared to preoperative values. However, outcomes did not significantly surpass those from spinal accessory nerve transfer. Electromyography showed a low incidence of motor unit action potentials in the deltoid. Medial pectoral nerve transfer to the axillary nerve did not yield superior results in shoulder abduction and deltoid reinnervation in our group of patients. At present, different nerve donors may also need to be considered for deltoid muscle reinnervation in patients with C5, C6, and C7 root avulsion to achieve better shoulder abduction recovery.

Peripheral Nerve Stimulation of the Axillary Nerve Improves Chronic Shoulder Pain and Dysfunction Following Reverse Total Shoulder Arthroplasty: A Case Report.

Reverse total shoulder arthroplasty (rTSA) is an effective procedure to improve shoulder pain, range of motion, and function for a variety of conditions, including glenohumeral osteoarthritis and rotator cuff arthropathy. However, up to 22% of patients have persistent shoulder pain 12 to 24 months following rTSA, even in the absence of surgical complications. Currently, there are no widely accepted non-pharmacological treatments for persistent postoperative pain after rTSA. This case report details the successful management of a 64-year-old woman with chronic postoperative shoulder pain following rTSA. She was treated with single-lead percutaneous peripheral nerve stimulation to the right axillary nerve for eight weeks with 12 Hz motor-level stimulation. She demonstrated improvement in shoulder flexion active range of motion, shoulder flexion strength, and shoulder abduction strength. Her Shoulder Pain and Disability Index total score improved from 26.93% to 8.46% one year following treatment. She reported an overall Global Rating of Change of +7 one year following treatment. This case's success demonstrates that short term peripheral nerve stimulation may provide long-term improvement of persistent post-operative pain and dysfunction in patients with painful rTSA.

Effects of Eccentric Versus Concentric Strengthening in Patients With Subacromial Pain Syndrome: A Randomized Controlled Trial.

Subacromial pain syndrome (SPS) is the most common cause of shoulder pain. Therapeutic exercise is the first-line treatment for SPS; however, the ideal exercise type remains unclear. Here, we compared the effects of eccentric and concentric strengthening in patients with SPS. Adding isolated eccentric strengthening to a multimodal physiotherapy program (MPP) would lead to greater improvements in outcomes compared with either MPP alone or adding isolated concentric strengthening to the MPP. Randomized controlled trial. Level 2. A total of 45 patients were randomized to eccentric strengthening (ESG), concentric strengthening (CSG), and control (CG) groups; all groups received the MPP. The strengthening groups also performed group-specific strengthening. Shoulder pain, abduction and external rotation (ER) strength, joint position sense (JPS), the Constant-Murley Score (CMS), and the Disabilities of the Arm, Shoulder and Hand score were collected at baseline, after 12 weeks of treatment, and at week 24. For CMS, ESG exhibited a greater, but not clinically meaningful, improvement than CSG and CG (P < 0.05). Eccentric abduction strength increased in ESG compared with CG. From baseline to follow-up, abduction strength increased in ESG compared with CSG and CG. Eccentric abduction strength increased in CSG compared with CG. JPS at abduction improved in the ESG compared with CG. Other between-group comparisons were not significant (P > 0.05). In SPS, eccentric strengthening provided added benefits, improving shoulder abduction strength and JPS at abduction, and was superior to concentric strengthening for improving shoulder abduction strength. Neither strengthening approach had an additional effect on shoulder function, pain, ER strength, or rotational JPS. Clinicians could implement eccentric strengthening as a motor control retraining for strength and proprioception gain rather than for pain relief and reducing disability.

Physical, functional and personal variables affecting shoulder complaints in healthcare workers.

Work-related shoulder disorders adversely affect the quality of life and lead to increased costs related to decreased productivity and injury treatment. Therefore, understanding the relationship between strength, upper extremity function and work ability contributes to the development of interventions aimed to improve the well-being of healthcare workers. Correlate shoulder abduction and handgrip strength with upper extremity function and work ability in healthcare workers with shoulder complaints. 67 workers with shoulder pain in the last year were assessed by Disability of Arm, Shoulder and Hand (QuickDASH), Work Ability Index (WAI), isokinetic shoulder strength and isometric handgrip strength dynamometers. Data were analysed with Spearman's Correlation Coefficient (ρ= 0.05), SPSS 20.0®. 52% males, mean age 48.4 years, 42% physically active, most administrative and general services workers. Low correlation between handgrip strength and QuickDASH (r=-0.359; p = 0.004); low correlation between handgrip strength and WAI (r = 0.359; p = 0.003) and between shoulder abduction strength and the QuickDASH (r = -0.267; p = 0.049); no significant correlation between shoulder abduction strength and WAI (r = 0.001; p = 0.997). Handgrip and shoulder abduction strength were inversely associated with upper extremity dysfunction. Shoulder abduction strength was associated with work ability. The inclusion of strength assessment in workers is important to guide strategies to prevent musculoskeletal disorders.

Association between Shoulder Dysfunction and Concomitant Neck Disability in Patients with Shoulder Disorders.

This study aimed to investigate the impact of shoulder dysfunction on concomitant neck disability in patients with shoulder disorders. The participants were patients with subacromial impingement syndrome (SIS) and frozen shoulder (FS). Twenty patients with SIS and 21 with FS without cervical radiculopathy were enrolled. The participants were assessed for the 4-week prevalence of neck pain, Neck Disability Index (NDI), shoulder strength and range of motion, a short version of the Disabilities of the Arm, Shoulder, and Hand questionnaire (quick-DASH), and the Pain Catastrophizing Scale (PCS). The 4-week prevalence of neck pain was 12 out of 20 (60%) in patients with SIS and 13 out of 21 (62%) in patients with FS. The median NDIs were 13 and 12 for SIS and FS, respectively, with no statistically significant difference. About 41% (17/41) of the participants displayed an NDI greater than the cutoff value for disability in daily living. Although shoulder abduction strength correlated with the NDI in patients with SIS, the PCS score correlated with the NDI in patients with FS. Concomitant neck disability is a critical concern for patients with shoulder disorders. The clinical factors related to concomitant neck disability differ between SIS and FS, with specific interventions recommended for each condition.

The feasibility of an upper limb strength test protocol in children with Duchenne muscular dystrophy

Question This study aimed to develop and assess a protocol for evaluating upper limb strength and its association with functional abilities in children and adolescents diagnosed with Duchenne muscular dystrophy (DMD). Design A cross-sectional study. Participants Eleven male individuals diagnosed with DMD (aged 11 to 18 years). Intervention A systematic protocol for assessing the maximum voluntary isometric contraction (MVIC) of the upper limbs using grip and pull dynamometers was developed and conducted in conjunction with the Performance of Upper Limb (PUL) scale. Outcome measures Feasibility was evaluated by appraising the number of participants capable of successfully executing the strength test protocol. Correlations were conducted to examine the relationship between upper limb strength and PUL scores. Results The grip strength assessment was feasible for all participants, while the complete strength testing protocol was feasible for nine, excluding two individuals with non-ambulatory mobility. Significant correlations were found between overall upper limb strength and total PUL scores (rs = 0.742, p = 0.022), grip strength and distal PUL scores (rs=0.733, p = 0.010), shoulder abduction strength and PUL shoulder scores (rs=0.905, p = 0.005), and grip strength and overall PUL scores (rs=0.794, p = 0.004). The middle-level correlation was not statistically significant (rs=0.590, p = 0.094). Conclusion The established strength test protocol demonstrated feasibility among ambulatory participants. However, alternative approaches are essential for those with limited ambulation. The study identified a robust correlation between upper limb strength and functional abilities. Further extensive studies are required to validate these findings. Trial registration The present study is a part of a longitudinal intervention study registered at the ClinicalTrials.gov (NCT03963453).

Influence of motor imagery training on hip abductor muscle strength and bilateral transfer effect.

Motor imagery training could be an important treatment of reduced muscle function in patients and injured athletes. In this study, we investigated the efficacy of imagery training on maximal force production in a larger muscle group (hip abductors) and potential bilateral transfer effects. Healthy participants (n = 77) took part in two experimental studies using two imagery protocols (∼30min/day, 5days/week for 2 weeks) compared either with no practice (study 1), or with isometric exercise training (study 2). Maximal hip abduction isometric torque, electromyography amplitudes (trained and untrained limbs), handgrip strength, right shoulder abduction (strength and electromyography), and imagery capability were measured before and after the intervention. Post intervention, motor imagery groups of both studies exhibited significant increase in hip abductors strength (∼8%, trained side) and improved imagery capability. Further results showed that imagery training induced bilateral transfer effects on muscle strength and electromyography amplitude of hip abductors. Motor imagery training was effective in creating functional improvements in limb muscles of trained and untrained sides.

Relationship between shoulder abduction strength and rotator cuff tear in elderly women: a general population study

ObjectivesTo investigate the effect of age-related rotator cuff tears on shoulder strength in a general population cohort.DesignCross sectional observational study.SettingThis study was set in an outpatient clinic setting in Chingford,...

Acute Intermittent Hypoxia and UE Strength and Function changes in Multiple Sclerosis: A Case Report

Background/Purpose Recovery of upper extremity (UE) function is a priority for individuals with multiple sclerosis (MS) whose disease sequalae often results in loss of UE strength and motor control. Acute Intermittent Hypoxia (AIH) is a novel intervention where an individual breathes bouts of air with low oxygen (∼9% O2) to set off a cascade of cellular events that may induce neuroplasticity and improve motor function. This intervention has shown promising effects in individuals with motor incomplete spinal cord injury (iSCI), even after a single bout. The purpose of this case report was to assess the ability of a single-bout AIH protocol to improve UE strength and function in an individual with chronic, relapsing-remitting MS. Methods A 30-year-old, right-handed female with a 10-year history of MS (Expanded Disability Status Scale score 3.0), who presented with LUE weakness and increased LUE tone participated in two treatment sessions. In the first session, she received a sham intervention where she was delivered normal room air, through the hypoxia generator for the entire treatment. The following week she received AIH. The 9-Hole Peg Test (9HPT) and Hand-held dynamometry (HHD) were performed immediately before and after the intervention Results Following the single bout of AIH, compared to baseline, left shoulder abduction strength increased 8% immediately after treatment and 21% at the 30-minute assessment. Left wrist extension strength increased 26% and 30%, respectively. Left shoulder flexion and elbow extension did not change. Comparatively, right shoulder abduction strength increased 27% and 7%. Right wrist extension strength increased 12% and 1%. Functionally, the participant's 9HPT time decreased from 44.88 to 41.41 seconds on her left but increased from 15.69 to 16.06 seconds on her right. Discussion AIH treatment was well tolerated by our participant and a single bout of AIH resulted in positive changes in UE strength and function on her more involved side. These results are promising, and further research is required to further assess safety, feasibility, and potential efficacy of AIH in people with MS. Recovery of upper extremity (UE) function is a priority for individuals with multiple sclerosis (MS) whose disease sequalae often results in loss of UE strength and motor control. Acute Intermittent Hypoxia (AIH) is a novel intervention where an individual breathes bouts of air with low oxygen (∼9% O2) to set off a cascade of cellular events that may induce neuroplasticity and improve motor function. This intervention has shown promising effects in individuals with motor incomplete spinal cord injury (iSCI), even after a single bout. The purpose of this case report was to assess the ability of a single-bout AIH protocol to improve UE strength and function in an individual with chronic, relapsing-remitting MS. A 30-year-old, right-handed female with a 10-year history of MS (Expanded Disability Status Scale score 3.0), who presented with LUE weakness and increased LUE tone participated in two treatment sessions. In the first session, she received a sham intervention where she was delivered normal room air, through the hypoxia generator for the entire treatment. The following week she received AIH. The 9-Hole Peg Test (9HPT) and Hand-held dynamometry (HHD) were performed immediately before and after the intervention Following the single bout of AIH, compared to baseline, left shoulder abduction strength increased 8% immediately after treatment and 21% at the 30-minute assessment. Left wrist extension strength increased 26% and 30%, respectively. Left shoulder flexion and elbow extension did not change. Comparatively, right shoulder abduction strength increased 27% and 7%. Right wrist extension strength increased 12% and 1%. Functionally, the participant's 9HPT time decreased from 44.88 to 41.41 seconds on her left but increased from 15.69 to 16.06 seconds on her right. AIH treatment was well tolerated by our participant and a single bout of AIH resulted in positive changes in UE strength and function on her more involved side. These results are promising, and further research is required to further assess safety, feasibility, and potential efficacy of AIH in people with MS.

Paper 03: Suprascapular Neuropathy: Two Distinct Presentations and Outcomes of Decompression

Objectives: Suprascapular neuropathy due to nerve compression or tension at the suprascapular notch is an uncommon source of shoulder pain and rotator cuff weakness with recent increased recognition and treatment. Long considered an elusive diagnosis, work-up can be lengthy and patients may experience treatment delay. We aimed to review presentation patterns and outcomes of arthroscopic suprascapular nerve decompression in a predominantly young and active military population. Methods: The surgical databases of two surgeons were queried for patients treated with arthroscopic suprascapular nerve decompression at the suprascapular notch from 2013 to 2021. Patient data, presentation and workup findings, and outcome measures were collected through review of the electronic medical record. Primary outcome measures were rate of return to active-duty military service, shoulder abduction and external rotation strength, and VAS pain scores. Secondary outcome measures were American Shoulder and Elbow Surgeons (ASES) Shoulder Score, Visual Analogue Scale (VAS), and Single Assessment Numerical Evaluation (SANE) score. Results: Twenty-five patients were identified. Average age was 26.6 years and follow-up 17.9 months (4-62 months). There were two distinct primary presentation types in this cohort: the chief complaint was pain in 13 patients (52%) and weakness in 12 (48%). Supraspinatus and/or infraspinatus atrophy was present on MRI in 10/12 patients with weakness and 0/13 with pain. Electromyography was positive in 9/12 with weakness and negative when obtained in 5 patients with pain. Ultrasound-guided suprascapular nerve injection was performed in 10/13 with pain and provided mean 91% symptom relief. Patients with pain had longer duration of pre-operative symptoms (22.2 [±13.1] vs. 10.3 [±13.6] weeks). Postoperatively, the pain group had significant improvement in VAS scores (6.2 [±1.6] to 1.0 [±0.9]), while the weakness group had significant improvement in abduction and external rotation motor grading (3.7 [±0.7] to 4.7 [±0.4] and 3.3 [±0.8] to 4.4 [±0.6] respectively). Return to duty or sport was 92% at a mean of 14.6 (±9.3) weeks. Conclusions: In this young, active cohort, suprascapular neuropathy presented with one of two distinct primary presenting complaints: pain or weakness. Given different expected work-up findings, categorizing patients into one of these two groups may be beneficial in effectively diagnosing and treating suprascapular neuropathy. Outcomes after arthroscopic suprascapular nerve release at the suprascapular notch predictably led to successful pain relief and strength improvement in patients presenting with pain and weakness respectively. [Table: see text][Table: see text]

A Surgical Framework for the Management of Incomplete Axillary Nerve Injuries.

Axillary nerve injury is the most common nerve injury affecting shoulder function. Nerve repair, grafting, and/or end-to-end nerve transfers are used to reconstruct complete neurotmetic axillary nerve injuries. While many incomplete axillary nerve injuries self-resolve, axonotmetic injuries are unpredictable, and incomplete recovery occurs. Similarly, recovery may be further inhibited by superimposed compression neuropathy at the quadrangular space. The current framework for managing incomplete axillary injuries typically does not include surgery. This study is a retrospective analysis of 23 consecutive patients with incomplete axillary nerve palsy who underwent quadrangular space decompression with additional selective medial triceps to axillary end-to-side nerve transfers in 7 patients between 2015 and 2019. Primary outcome variables included the proportion of patients with shoulder abduction M3 or greater as measured on the Medical Research Council (MRC) scale, and shoulder pain measured on a Visual Analogue Scale (VAS). Secondary outcome variables included pre- and postoperative Disabilities of the Arm, Shoulder, and Hand Questionnaire (DASH) scores. A total of 23 patients met the inclusion criteria and underwent nerve surgery a mean 10.7 months after injury. Nineteen (83%) patients achieved MRC grade 3 shoulder abduction or greater after intervention, compared with only 4 (17%) patients preoperatively (p = 0.001). There was a significant decrease in VAS shoulder pain scores of 4.2 ± 2.5 preoperatively to 1.9 ± 2.4 postoperatively (p < 0.001). The DASH scores also decreased significantly from 48.8 ± 19.0 preoperatively to 30.7 ± 20.4 postoperatively (p < 0.001). Total follow-up was 17.3 ± 4.3 months. A surgical framework is presented for the appropriate diagnosis and surgical management of incomplete axillary nerve injury. Quadrangular space decompression with or without selective medial triceps to axillary end-to-side nerve transfers is associated with improvement in shoulder abduction strength, pain, and DASH scores in patients with incomplete axillary nerve palsy.

Biomechanical and functional analysis of the shoulder complex and thoracic spine in patients with subacromial impingement syndrome: A case control study.

The motions of the shoulder are mainly carried out through the glenohumeral joint, but are also assisted by the scapulothoracic joint. Therefore, changes in the biomechanics of the thoracic spine and scapula affect the function of the shoulder. However, there is limited information on the biomechanical and functional characteristics of the shoulder complex and thoracic spine in patients with subacromial impingement syndrome (SIS). In this study, the biomechanical and functional characteristics of the shoulder complex and thoracic spine were analyzed in patients with SIS compared to healthy individuals. A total of 108 participants were included in this study. Participants were classified into 2 groups, the SIS (n = 55) and healthy (n = 53) groups. The shoulder and thoracic range of motion (ROM), scapular position, and isokinetic shoulder strength were measured in all participants. The shoulder ROM was significantly decreased in the SIS group compared to the healthy group (P < .001). The thoracic spine ROM showed significantly limited extension in the SIS group (P < .001). The scapular position showed significantly increased anterior tilting (P = .005), internal rotation (P = .032), protraction (P < .001), and decreased upward rotation (P = .002) in the SIS group. The isokinetic shoulder external rotation (P < .001) and abduction (P < .001) strength were significantly lower in the SIS group. Patients with SIS showed reduced shoulder ROM and end-range extension of the thoracic spine compared to healthy individuals, and the scapula was in a more anterior-tilted, protracted, and downward rotated position. In addition, it showed lower external rotation and abduction strength. These results suggest the need for interventions to improve the limited thoracic extension and altered scapular position, which may affect shoulder ROM and muscle strength in the rehabilitation of patients with SIS.

The shoulder abductor strength is a novel predictor of tracheostomy in patients with traumatic cervical spinal cord injury

BackgroundEarly prediction of tracheostomy in traumatic cervical spinal cord injury (TCSCI) patients is often difficult. This study aims to clarify the association between shoulder abductor strength (SAS) and tracheostomy in patients with TCSCI.MethodsWe retrospectively analyzed 513 TCSCI patients who were treated in our hospital. All patients were divided into a tracheostomy group and a non-tracheostomy group. The SAS was assessed using the Medical Research Council (MRC) Scale for Muscle Strength grading. Potential predictors were assessed for their association with tracheostomy in patients. A nomogram was developed based on multivariable logistic regression analysis (MLRA) to visualize the predictive ability of the SAS. Validation of the nomogram was performed to judge whether the nomogram was reliable for visual analysis of the SAS. Receiver operating characteristics curve, specificity, and sensitivity were also performed to assess the predictive ability of the SAS.ResultsThe proportion of patients with the SAS grade 0–2 was significantly higher in the tracheostomy group than in the non-tracheostomy group (88.1% vs. 54.8%, p = 0.001). The SAS grade 0–2 was identified as a significant predictor of the tracheostomy (OR: 4.505; 95% CI: 2.080–9.758; p = 0.001). Points corresponding to both the SAS grade 0–2 and the neurological level of injury at C2-C4 were between 60 and 70 in the nomogram. The area under the curve for the SAS grade 0–2 was 0.692. The sensitivity of SAS grade 0–2 was 0.239. The specificity of SAS grade 0–2 was 0.951.ConclusionsSAS is a novel predictor of tracheostomy in patients after TCSCI. The SAS grade 0–2 had a good predictive ability of tracheostomy.

Double Fascicular Nerve Transfer to Restore Elbow Flexion Following Neuralgic Amyotrophy: A Case Report

Double fascicular nerve transfer (DFNT) involves transferring fascicles from the median and ulnar nerves to the musculocutaneous nerve to restore elbow flexion. We performed this procedure on a patient who was diagnosed with neuralgic amyotrophy (NA) 2 years previously. We aimed to investigate the short-term outcomes and feasibility of DFNT applied to non-traumatic neuropathy. A 63-year-old, right-handed man presented to us with persistent right elbow flexion weakness 24 months after receiving the diagnosis of NA. On examination, biceps strength was 0/5, and shoulder abduction strength was 3/5. Magnetic resonance neurography demonstrated muscle atrophy in the upper trunk. DFNT was considered to restore elbow flexion. The donor and recipient fascicles were then coapted (flexor digitorum superficialis to biceps brachii, flexor carpi ulnaris to brachialis). Postoperatively, paresthesia was reported in the area of ulnar innervation, and the patient complained of hand clumsiness. From postoperative day 10 onward, biceps muscle contracture was identified and on the 14th day, grade 3 elbow flexion strength was observed. We suggest that DFNT may be a safe and effective method to restore elbow flexion in patients with NA.

Quantifying Donor Deficits Following Nerve Transfer Surgery in Tetraplegia

Nerve transfer (NT) surgery can improve function in people with cervical spinal cord injury (SCI). However, the impact of donor nerve deficits remains unclear. The purpose of this study was to quantify donor deficits experienced by individuals with cervical SCI following NT. This prospective single-arm, comparative study included people with SCI undergoing upper extremity NTs. Myometry was used to assess muscle strength at baseline and follow-up. The Spinal Cord Independence Measure was used to measure the ability to perform activities of daily living. Ten individuals underwent 20 NTs to restore elbow extension (donor, posterior deltoid; n= 2), hand opening (donor, supinator; n= 7), and hand closing (donor, brachialis; n= 11). Shoulder abduction strength decreased (-5.6% at early and-4.5% late follow-up) in the elbow extension NT. Wrist extension strength decreased at early (-46.9% ± 30.3) and increased by late (76.4% ± 154.0) follow-up in the hand opening NT. No statistically significant change in elbow flexion strength was noted in the hand closing NT. Spinal Cord Independence Measure scores did not change significantly between baseline and early postoperative follow-up; they improved at late follow-up. Use of expendable donor nerves with redundant function to perform NT surgery has relatively little impact on strength or capacity to perform activities of daily living, even in the unique and highly vulnerable SCI population. Early, temporary loss in wrist extension strength can be seen after the supinator to posterior interosseous nerve transfer. This study offers quantitative data about possible diminution of donor function after NT, enabling hand surgeons to better counsel individuals contemplating upper extremity reconstruction. Prognostic I.

P.08 Phase 1 open-label trial of Rycal S48168 (ARM210) for RYR1-related myopathies

Pathogenic variants in the <i>RYR1</i> gene, encoding the skeletal muscle ryanodine receptor (RyR1), are the most common cause of non-dystrophic neuromuscular disorders. Pathogenic <i>RYR1</i> variants exhibit downstream consequences, including aberrant sarcoplasmic reticulum (SR) Ca²⁺ leak, hypersensitivity to RyR1 agonists, diminished SR Ca²⁺ release, and/or decreased RyR1 protein expression. Decreased RyR1-calstabin1 association, due to <i>RYR1</i> variants and/or post-translational modifications of the RyR1 channel, exacerbates SR Ca²⁺ leak with detrimental downstream effects on muscle function. Rycal compounds have been shown to restore RyR1-calstabin1 association, stabilize the <i>RyR1</i> closed state, and mitigate aberrant Ca²⁺ leak in <i>RYR1</i>-related myopathy (<i>RYR1</i>-RM) muscle biopsies. We conducted a phase 1 trial of S48168 (ARM210), a Rycal compound, in ambulatory adults with <i>RYR1</i>-RM (NCT04141670). The primary endpoint was safety and tolerability over a one-month dosing period. Pharmacokinetic (PK) studies, muscle biopsies, motor/muscle function tests, and a patient-reported fatigue questionnaire were also included. Seven eligible individuals were enrolled and received either the low dose (120 mg, n=3) or high dose (200 mg, n=4) of S48168 (ARM210) daily. Three treatment emergent adverse effects grade 2 or above were reported, all unrelated to S48168 (ARM210) and there were no serious adverse events. S48168 (ARM210) showed a dose-dependent PK profile and C_max remained within pre-defined safety margins. At one month, self-reported fatigue scores decreased and shoulder abduction strength trended higher in the high dose group, while handgrip strength increased in both dose groups, though these exploratory comparisons were descriptive. Other preliminary efficacy results were mixed. Given the favorable safety profile and efficacy trends, further clinical development of S48168 (ARM210) is warranted for <i>RYR1</i>-RM.

Evaluating the Influence of Gravity on Shoulder Strength Measures Assessed via Handheld Dynamometry.

Handheld dynamometry is a feasible, reliable, and cost-effective method for assessing shoulder strength. One limitation to this tool is the lack of standardized testing protocols and specified shoulder strength test positions. Although it is recommended that strength tests be performed in a gravity-eliminated position, this may not always be a feasible or practical testing protocol. There is limited research on the influence of gravity on strength measures; to our knowledge, no study has compared handheld dynamometry shoulder strength assessments based on body position and gravity. Therefore, the purpose of this study was to compare shoulder flexion, extension, and abduction strength assessed via handheld dynamometry between a gravity-eliminated and a gravity-influenced test position. This study was a comparison of shoulder strength based on test position. The test position was the independent variable, and the dependent variables were shoulder flexion, extension, and abduction strength. Supine (gravity-eliminated) and seated (gravity-influenced) strength measures were assessed in 20 healthy adults (19.4 [1.2]y) on the dominant arm. Paired t tests were used to determine differences between body positions for each test. Significance was accepted at P ≤ .05. There were no differences between supine and seated flexion and extension measures. Absolute supine shoulder abduction scores (152.5 [58.4]N) were significantly higher than seated scores (139.9 [55.6]N). Findings show that gravity should be considered when using handheld dynamometry scores as indicators of abductor shoulder strength and function.