Arm Abduction Research Articles

Arm position on portable neonatal/infant ICU chest radiograph can mimic lamellar effusion

Introduction/BackgroundArm malposition in neonatal ICU radiographs may result in overlap of the arm soft tissues and chest wall giving the appearance of lamellar effusions. We aimed to determine the frequency of arm malposition on portable neonatal/infant intensive care unit (N/IICU) chest radiographs and the proportion of these mimicking lamellar effusions. Material and MethodsWe evaluated a subgroup of supine portable chest radiographs performed at the N/IICU. Two reviewers, at a tertiary pediatric hospital located in the USA, evaluated each radiograph in consensus and classified arm position for either side independently as (1) acceptable: arm abducted and separated from the chest and (2) compromised: arm down and in contact with chest soft tissue. The compromised cases were evaluated regarding any overlap between soft tissues of the arm and chest of sufficient degree to mimic a lamellar effusion. ResultsWe reviewed 300 radiographs performed at the N/IICU (600 hemithoraces). The mean age was 1.8 ± 1.8 months. Of 600 hemithoraces, 233 (39%) showed arms down and in contact with the chest. In seven (1%) cases, the arm position was compromised and mimicked a lamellar effusion. We identified 32 (5%) true lamellar effusions in the whole sample; in 14 of the 32 cases with lamellar effusion, the radiographs were performed with the arms down. ConclusionPortable chest radiographs performed in the N/IICU without proper arm abduction represent a potential for misinterpretation of chest radiographs. Although the prevalence of mimickers of lamellar effusion is only around 1%, the prevalence of arms down on a portable chest radiograph is considerably high (39%).

Arm abduction angle at ball release influences shoulder forces and torques during the windmill softball pitch

Objectives:Shoulder pain and ligamentous injury is a common complaint among fast pitch softball pitchers. In addition to extreme shoulder joint motion during pitch delivery, sudden deceleration immediately after ball release places increased stress across the shoulder joint. Some pitchers release the ball with the throwing arm tucked close to the trunk, while others let the arm float outwards in a more abducted position. The position of the arm at ball release (BR) may be key to the mechanism of shoulder pain. Previous work demonstrated that during the change up pitch, softball pitchers with upper extremity pain demonstrated greater shoulder abduction at stride and less trunk lateral flexion at BR compared to athletes without pain (Oliver et al 2018). The purpose of this study was to test the hypothesis that placement of the arm closer to the trunk (shoulder adduction) at ball release will produce less shoulder stress during fastball windmill pitches.Methods:Twenty-six female fast pitch softball pitchers with a mean age of 18 +/- 6 y, including 16 high school, 7 collegiate, and 3 professional athletes, underwent 3D biomechanical pitch analyses using 20 Vicon high-speed motion capture cameras (240 hz). All pitchers threw the standard 13.11 m mound-to-plate distance at a strike zone target while a radar gun collected pitch speeds. The fastest, most accurate fastball pitches for each subject were selected for analyses (average of 5 pitches per subject). A total of 103 pitches were used to calculate: shoulder abduction angle and shoulder compression force during the BR phase (10 frames surrounding BR) and peak shoulder torques. Pearson correlations were performed to determine the relationship of shoulder frontal plane (adduction/abduction) angle during the ball release phase to these biomechanical measures.Results:The smallest abduction shoulder angle reached during the BR phase (avg: 14.06 +/- 6.71 degrees) demonstrated a significant positive correlation with shoulder compression force, p=0.008 and with peak flexion torque, p< 0.001 (Table 1). This shoulder abduction angle during the BR phase demonstrated negative correlations with peak shoulder adduction torque, p<0.001 and shoulder internal rotation torque, p< 0.001.Conclusion:These initial findings support the hypothesis that pitchers who release the ball with their arm close to their trunk demonstrate lower shoulder compression forces and shoulder flexion torques than those with a more abducted arm position. Future studies are needed to explore the interplay of pitching technique mechanics, shoulder joint stresses, and injury history to inform pitching instruction and injury prevention efforts.Table 1.The relationship between shoulder frontal plane angle during ball release with shoulder compression force and torquesMeasureAverage SDRPBall release phase peak shoulder compression force7.791.53 BW0.258*0.008Peak shoulder internal rotation torque-27.4528.65 Nm-0.377*P < 0.001Peak shoulder adduction torque-47.8649.59 Nm-0.479*P < 0.001Peak shoulder flexion torque60.7946.01 Nm0.530*P < 0.001*Established level of significance p<0.05

Changes in In Vivo Glenohumeral Joint Contact Patterns After Arthroscopic Superior Capsule Reconstruction

Objectives:Patients with irreparable rotator cuff tears (RCT) exhibit functional limitations believed to be caused by superior migration of the humerus1,2. One viable treatment is superior capsule reconstruction (SCR). SCR has been shown to restore stability of the glenohumeral (GH) joint in cadavers1, but its effectiveness at controlling in vivo humeral motion is unknown. Outcomes are typically evaluated through standard clinical radiographs to assess acromial-humeral distance (AHD), and patient-reported outcomes (PROs) such as ASES and Visual Analog Scale3. Reported changes in AHD are inconsistent, with some studies reporting an increase in AHD of 2.6 to 3.2 mm4,7, while other studies reported no significant change5,6 in AHD after SCR. Scapulohumeral rhythm (SHR), a measure of shoulder motion fluidity, has been reported at 2:1 (glenohumeral to scapulothoracic motion) in healthy individuals9, but the effects of SCR on SHR are unknown. The aim of this study was to determine the effect of SCR on static and dynamic AHD, shoulder function, and patient-reported outcomes. We hypothesized that after SCR, static and dynamic AHD would increase, SHR would approximate that of a healthy shoulder, maximum GH abduction would increase, and PROs would improve.Methods:Ten patients with irreparable RCT provided informed consent prior to receiving human dermal allograft SCR. To date, seven (6M, 1F, age 60 ± 8 years) have returned for 1 year post-operative testing. ASES, DASH, and WORC surveys were completed before (PRE), 6 months (6MO-POST), and 1-year after SCR (1YR-POST). Synchronized biplane radiographs of the shoulder were collected PRE and 1YR-POST at 50 images/s while patients performed 3 trials of scapular plane arm abduction. Six degree of freedom GH and scapular kinematics were determined with sub-millimeter accuracy by matching subject-specific CT-based bone models of the humerus and scapula to radiographs using a validated volumetric tracking technique8. AHD was calculated as the minimum distance between the acromion and the humerus at 5° increments of GH abduction. Scapulohumeral rhythm (SHR) was calculated by finding the average change in glenohumeral abduction per degree of scapular upward rotation during scapular abduction.Differences between PRE and 1YR-POST SHR and static AHD distance were evaluated using a paired t-test with significance set at p < 0.05. Changes in PROs were compared to the minimum clinically important difference (MCID).Results:There was a trend toward decreasing static AHD from PRE to 1YR-POST (average decrease: 1.5±1.6mm (p=0.06), however, dynamic AHD did not change from PRE to 1 YR-POST between 45° and 95° of glenohumeral abduction (all p > 0.11) (Figure 1). There was a trend toward increased SHR from 1.1 ± 0.5 PRE to 1.5 ± 0.3 1YR-POST (p = 0.08) (Figure 2), while the increase in maximum GH abduction during scapular abduction from PRE (76.7°±24.5°) to 1YR-POST (91.8°±14.9°) was not statistically significant (p = 0.14) (Figure 2). ASES, WORC, and DASH scores improved beyond the minimum clinically important difference from PRE to 1YR-POST (Table 1) for all patients.Conclusion:In general, SHR tended to more closely resemble that of a healthy shoulder following SCR. Althoughaverage maximum GH abduction was higher postoperatively than preoperatively, that increase was not statistically significant and may reflect that most patients in our cohort had reasonable preoperative abduction. In contrast to those quantitative measures of shoulder function, patient-reported qualitative outcomes all improved significantly. Conflicting results between static and dynamic AHD during higher glenohumeral abduction angles suggest SCR does not appear to affect AHD in higher abduction angles, though the static AHD suggests there may be a difference at lower abduction angles. Dynamic measurements of AHD at lower abduction angles will be necessary to fully characterize the dynamic changes of AHD following SCR.Figure 1.Patient-reported outcomes. Bolded scores represent changes greater than the minimum clinically important different (MCID) compared to PRE and average contact center locations ± 1 standard deviation throughout scapular plane abdjuction. Black + indicates the glenoid center with anterior (A) and posterior (P) directions indicated on the glenoid.

Upper limb kinematics during the first year after stroke: the stroke arm longitudinal study at the University of Gothenburg (SALGOT)

BackgroundReduction of compensation and improved movement quality indicate recovery after stroke. Since clinical measures alone are often inadequate to distinguish between behavioral recovery and compensation, kinematic analysis of functional tasks has been recommended.ObjectiveTo quantify longitudinal changes and residual deficits in movement performance and quality during the first year after stroke using kinematic analysis of drinking task.MethodsA total of 56 participants with first ever stroke causing upper extremity impairment were extracted from a non-selected stroke unit cohort (Stroke Arm Longitudinal Study at the University of Gothenburg-SALGOT). Participants needed to able to perform the drinking task with the more-affected arm at least on 2 occasions out of 6 (3 days, 10 days, 4 weeks, and 3, 6, and 12 months) during the first year to be included. A cohort of 60 healthy individuals was used as reference. Longitudinal changes were analyzed using linear mixed models.ResultsMovement time, number of movement units, peak angular velocity of the elbow, peak hand velocity, and trunk displacement improved significantly over the first 3 months with a peak at 6 months. Movement time and peak hand velocity reached levels comparable to healthy at 3 months, but number of movement units, peak elbow angular velocity, trunk displacement, and arm abduction remained different from healthy over the first year after stroke.ConclusionsEven when the recovery patterns of kinematics follow the known nonlinear pattern, not all kinematic measures reach the levels in par with healthy controls at one year post stroke. Since the number of movement units, peak angular velocity, trunk displacement, and arm abduction remained impaired over the first year, they might be the most suited measures to distinguish behavioral recovery from compensation strategies.Trial registrationClinicalTrials: NCT01115348. 4 May 2010. Retrospectively registered.

Impact of scapular notching on glenoid fixation in reverse total shoulder arthroplasty: an in vitro and finite element study

The high incidence of scapular notching in reverse total shoulder arthroplasty (RTSA) has spurred several methods to minimize bone loss. However, up to 93% of RTSAs accompanying scapular notching have been reported to maintain good implant stability for over 10 years. This study was conducted to investigate the relationship between scapular notching and glenoid fixation in RTSA. Cadaveric testing was performed to measure the notch-induced variations in strain on the scapular surface and micromotion at the bone-prosthesis interface during arm abductions of 30°, 60°, and 90°. Finite element analysis was used to further study the bone and screw stresses as well as the bone-prosthesis micromotion in cases with a grade 4 notch during complicated arm motions. The notch resulted in an apparent increase in inferior screw stress in the root of the screw cap and at the notch-screw conjunction. However, the maximum stress (172 MPa) along the screw after notching is still much less than the fatigue strength of the titanium screw (600 MPa) under cyclic loading. The bone-prosthesis micromotion results did not present significant notch-induced variations. Scapular notching will lead to few impacts on the stability of an RTSA on the glenoid side. This finding may explain the long-term longevity of RTSA in cases of severe scapular notching. The relationship between scapular notching and weak regions along the inferior screw may explain why fractures of the inferior screw are sometimes reported in patients with RTSA clinically.

P48 A case of myasthenia gravis presenting to the rheumatology clinic

Abstract Background A 32-year-old Lithuanian lady, with a 6-year history of undifferentiated inflammatory arthritis and autoimmune neutropenia, contacted her rheumatologist reporting a constellation of new symptoms. This began with a month’s history of facial weakness and slurred speech. She progressively experienced nasal regurgitation on drinking fluids, reduced exercise tolerance, as well as difficulty chewing, swallowing, and coughing. Her symptoms initially came on in the evening but subsequently appeared earlier in the day. There were no symptoms suggestive of infection. Her arthritis had been well-controlled on hydroxychloroquine and sulfasalazine. She was previously on methotrexate, but this was discontinued due to plans to conceive. Methods Clinical examination during an urgent outpatient review yielded dysphonic, mildly dysarthric speech. Extraocular movements were normal with no ophthalmoplegia. There was mild lower motor neurone facial weakness and an absent gag reflex. She demonstrated fatiguability on repetitive tongue movements and arm abduction. There were no upper motor neurone or cerebellar signs. Blood tests showed normal inflammatory markers, full blood count, creatine kinase, immunoglobulins, liver, and renal profile. Her anti-nuclear antibody titre, previously weakly positive at time of diagnosis of inflammatory arthritis, was 1:1280 (homogenous). Anti-cyclic citrullinated peptide, rheumatoid factor, and extractable nuclear antigens were negative. Virology screen was unremarkable. Neurology input was sought. Anti-acetylcholine receptor antibody was positive at 5.2nmol/L (normal range 0-0.45nmol/L), anti-muscle specific receptor tyrosine kinase antibody was negative. Nerve conduction studies showed decremental response on repetitive stimulation of her left nasalis, consistent with a post-synaptic neuromuscular junction transmission disorder. There was no evidence of myopathy. Results The clinical symptoms and the investigations led to the diagnosis of myasthenia gravis with predominant bulbar features. Computed tomography showed no evidence of thymoma or thymic hyperplasia. Magnetic resonance imaging of the brain showed no evidence of space-occupying lesion or brainstem abnormality. She initially received pyridostigmine 30mg three times daily with propantheline cover to which she reported a good response. A viral illness led to deterioration of her symptoms of breathlessness and worsening dysphagia resulting in a hospital admission. She received intravenous immunoglobulins 20g daily for three days. Hydroxychloroquine and sulfasalazine were replaced with methotrexate 15mg weekly. She now remains on pyridostigmine 90mg five times daily and 10mg prednisolone daily with good effect. Conclusion Myasthenia gravis is a rare condition (prevalence of 10-20 per 100,000 in the United Kingdom). However, this occurs at a higher prevalence in autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus. This case illustrates the importance of remaining vigilant about symptoms which patients may disclose in the rheumatology clinic which may not fit with their known diagnosis. Her previous use of methotrexate for her arthritis could have masked her myasthenic symptoms which became apparent after the drug was stopped for a prolonged period. Disclosures S. Yeoh None. S. Salam None. G. Christofi None. V. Morris None.

Microsurgical Resection of Lung Carcinoma Spinal Cord Metastasis: 2-Dimensional Operative Video.

This video demonstrates microsurgical resection of intramedullary spinal cord metastasis of lung adenocarcinoma. Lung cancer is the predominant cause of rare metastatic intramedullary involvement of the spinal cord.1-4 Because of severe disabilities, these tumors should be considered for treatment with the goal of complete removal to preserve neurological functioning.5-9 Surgical resection improves symptoms, preserves ambulatory status, and increases survival time twice that of nonsurgical treatments.3,8,10 Surgery can be effective in arresting neurological decline.11,12 To our knowledge, this is the first video report of an intramedullary spinal cord metastasis resection. A 69-yr-old male with history of lung cancer presented with acute onset left arm abduction, forearm flexion, and hand weakness (3/5) and gait disturbance. Cervical spine MRI revealed C4/C5 nonhomogenously enhancing intramedullary tumor measuring 22×10×7 mm. Sagittal T2-weighted image demonstrated extensive cord edema. The C4 and C5 laminectomies were performed. Microsurgical techniques were employed.13-15 Metastasis involved the left lateral aspect of the cord with invasion of 2 left dorsal sensory nerve roots, which were resected. Further transection of the dentate ligament relaxed the spinal cord, enabling safer tumor resection. Pial dissection using bipolar forceps, microscissors, and microdissector enabled tumor delivery. Following resection, dural closure was reinforced with previously harvested fat tissue graft to prevent CSF leak.16 Postoperative MRI revealed complete macroscopic resection with improvement of spinal cord swelling. Patient improved his gate and his left arm motor strength was stable. Subsequently, patient received focal adjuvant radiotherapy. Written consent was obtained directly from the patient.

A Comparison Study on the Electrical Activity of Arm Abduction Muscles During Shoulder Abduction and Scaption Between Shooting Disciplines

Objective: Considering the positions that the shooter chooses during shooting in different disciplines, it seems that the activity of deltoid and supraspinatus muscles which are common muscles during movement, varies in different disciplines. Therefore, the purpose of the present study was to evaluate and compare the electrical activity of deltoid and supraspinatus muscles between three shooting disciplines. Methods: 24 shooters (8 archers, 8 air pistol shooters, and 8 air rifle shooters) participated in the study. They performed shoulder abduction and scaption at 60 and 90 degrees. The electrical activity of deltoid and supraspinatus muscles was then recorded using surface electromyography. The data were analyzed by using ANOVA and Tukey’s test at the significance level of P&lt;0.05. Results: The activity of anterior deltoid muscle at 60 and 90 degrees of abduction and the activity of middle deltoid and supraspinatus muscles only at 90 degree of abduction was significantly higher in the archery group than in the air pistol group (P&lt;0.05). Conclusion: The higher electrical activity of deltoid and supraspinatus muscles in archery sport may be related to the tensile force of the bow and the greater arm angle at the shoulder joint during this type of shooting compared to air pistol and air rifle shooting.

Measurement of Outlet Pressures Favors Rib Resection for Decompression of Thoracic Outlet Syndrome

When conservative therapy for thoracic outlet syndrome fails, scalenectomy with or without first-rib resection (FRR) is the treatment of choice. We measured pressure in the costoclavicular space before and after FRR at time of neurogenic thoracic outlet syndrome release to evaluate whether FRR is required to completely decompress the costoclavicular space. Using a supraclavicular exposure for anterior-middle scalenectomy with FRR, costoclavicular space pressures were measured using a balloon catheter with the patient's arm in neutral anatomic position, secondarily, the arm abducted and externally rotated. Pressures were recorded in both arm positions before scalenectomy, after scalenectomy, and after FRR. Paired Student's t test was used to compare differences in group means for paired samples. Patient-reported outcomes were reported using the Derkash classification and quick disabilities of the arm, shoulder, and hand (qDASH) questionnaire. Fifteen patients (16 cases) surgically treated for neurogenic thoracic outlet syndrome were included in this retrospective study. There was no significant difference in pressure change between arm positions before scalenectomy (161.56 ± 71.65 mm Hg difference) or after scalenectomy (148.5 ± 80.24 mm Hg difference). There was a significant difference in pressure change between post-scalenectomy and post-FRR arm positions; mean pressure change between arm positions after FRR was 50.56 ± 40.28 mm Hg. Mean postoperative qDASH score was 20 ± 23.2. All patients reported improvement in symptoms and functional status. Supraclavicular first rib resection for management of neurogenic thoracic outlet syndrome can be safely performed with favorable outcomes. The pressure increase in the costoclavicular space caused by arm abduction and external rotation was significantly reduced only after FRR, raising concerns about potential incomplete costoclavicular space decompression with scalenectomy alone for neurogenic thoracic outlet syndrome management.

Stress distribution in the humerus during elevation of the arm and external abduction

ObjectiveThe purpose of this study is to estimate stress distribution occurring in the humerus during elevation and external rotation of the arm.Methods: contact forces and moments were estimated using telemeterized shoulder implants. An accurate three-dimensional (3D) finite element (FE) model of the natural scapula was developed, and loaded by data obtained by instrumented prosthesis. ResultsStresses of about 40 MPa were found on the homerus during the elevation phase acting at 30° and 80°, while a peak of 60 MPa was found during the external rotation phase at 20°. The stress aging on scapula was of about 45 MPa, while the acromion was subjected at about 30 MPa. Stresses aging on ligaments were of about 15 MPa. ConclusionThese results indicated that the transfer of major muscle and joint reaction take place predominantly through the thick bony ridges, and stresses induced can be dangerous especially for patients with shoulder problems or during the first post-operative weeks after shoulder fractures or joint replacements.

Relationship between anthropometric and electromyographic variables of the scapular muscles

PurposeTo determine the relationship between skinfolds and onset latency of scapular muscles in healthy young adults.MethodsA cross-sectional study was carried out at the Biomechanics and Motor Control Laboratory of Saint Thomas University, Talca, Chile. Overall, 36 participants between 18 and 24 years of age were selected. The axillary, pectoral, and subscapular skinfolds were measured, as well as the electromyographic onset latency of the scapular muscles (serratus anterior and trapezius) when performing a voluntary arm abduction task. The Pearson correlation coefficient was used.ResultsThere was a positive correlation between the axillary skinfold and the lower trapezius (&lt;i&gt;r&lt;/i&gt; = 0.51, &lt;i&gt;p&lt;/i&gt; = 0.002) and serratus anterior (&lt;i&gt;r&lt;/i&gt; = 0.53, &lt;i&gt;p&lt;/i&gt; = 0.001) muscle onset latencies, and also between the subscapular skinfold and the lower trapezius (&lt;i&gt;r&lt;/i&gt; = 0.38, &lt;i&gt;p&lt;/i&gt; = 0.022) and serratus anterior (&lt;i&gt;r&lt;/i&gt; = 0.73, &lt;i&gt;p&lt;/i&gt; &lt; 0.001) muscle onset latencies.ConclusionsDuring a voluntary abduction arm movement, a greater thickness of axillary and subscapular skinfolds is related to an increase in the lower trapezius and serratus anterior muscle onset latencies.

Clinical effectiveness of ultrasound guided subacromial-subdeltoid bursa injection of botulinum toxin type A in hemiplegic shoulder pain: A retrospective cohort study.

Hemiplegic shoulder pain (HSP), which occurs in most patients with hemiplegia, causes considerable distress and worsens outcomes in rehabilitation. Although they have received the treatments such as anti-inflammatory drugs or physical therapy, many of the individuals remain suffering from shoulder pain 6 months after acute stroke event. In this retrospective study, we evaluated the effectiveness of ultrasound guided subacromial-subdeltoid (SASD) bursa injections with botulinum toxin type A (BoNT/A) compared to steroids for refractory HSP.The data were collected retrospectively by reviewing the patient's medical records and pain questionnaires in our rehabilitation center. In total, 38 patients who received ultrasound guided SASD bursa injection (BoNT/A group, n = 18; corticosteroid group, n = 20) were included. The pain visual analog scale (VAS) score at rest and during arm passive abduction, Fugl-Meyer score of upper limbs (F-M score) were evaluated before, 2, 4, 8, and 12 weeks after injection.Both 2 groups obtained a significant improvement of VAS score at rest or during arms passive abduction compared to baseline score (within group compare, P < .05). There were no significant differences of pain score improvement between two groups at week 2, 4, 8, and 12 after injection either at rest or during passive arm abduction (between 2 groups compare, P > .05). There were also no differences in results of the post treatment F-M score between 2 groups (between 2 groups compare, P > .05). Similarly, during the follow-up period no collateral effects were reported after BoNT/A injection.SASD bursa BoNT/A injection can substantially reduce the pain as corticosteroid in patients with HSP. BoNT/A injection could be a useful strategy for replacing steroids as a treatment for refractory HSP especially in the patients who cannot tolerate the steroids injection.

Anatomy and Biomechanic of the Shoulder

The shoulder is one of the most complex joints of the human body. Consequently, they are susceptible to injury and degeneration. Mechanical shoulder pathology typically results when overuse, extremes of motion, or excessive forces overwhelm intrinsic material properties of the shoulder complex resulting in tears of the rotator cuff, capsule, and labrum.The fundamental central component of the shoulder complex is the glenohumeral joint. It has a ball-and-socket configuration with a surface area ratio of the humeral head to glenoid fossa of about 3:1 with an appearance similar to a golf ball on a tee. Overall, there is minimal bony covering and limited contact areas that allow extensive translational and rotational ability in all three planes.The glenohumeral joint has 2 groups of stabilizers, which are static (passive) and dynamic (active) restrains. Static stabilizers include the concavity of the glenoid fossa, glenoid fossa retroversion and superior angulation, glenoid labrum, the joint capsule, and glenohumeral ligaments, and a vacuum effect from negative intra-articular pressure.Dynamic stabilization is merely the coordinated contraction of the rotator cuff muscles that create forces that compress the articular surfaces of the humeral head into the concave surface of the glenoid fossa.During upper extremity movement, the effects of static stabilizers are minimized and dynamic or active stabilizers become the dominant forces responsible for glenohumeral stabilityThe simple act of arm elevation is a complex task that occurs via the combination of glenohumeral and scapulothoracic motion, together known as scapulohumeral rhythm. In the first 1200, glenohumeral arm abduction, the supraspinatus and deltoid work together and create a force couple that promotes stability, while raising the arm (deltoid contraction).In addition, the humerus must undergo 450 external rotation to not only clear the greater tuberosity posteriorly but also loosen the inferior glenohumeral ligament (IGHL) to allow maximum elevation.There are several anatomical updates regarding the rotator cuff and capsular footprint. The footprint of the supraspinatus on the greater tuberosity is much smaller than previously believed, and this area of the greater tuberosity is actually occupied by a substantial amount of the infraspinatus. The superior-most insertion of the subscapularis tendon extends a thin tendinous slip, which attaches to the fovea capitis of the humerus. The teres minor muscle inserts to the lowest impression of the greater tuberosity of the humerus and additionally inserts to the posterior side of the surgical neck of the humerus.

NONPRODUCTIVE COUGH AS PREAMBLE OF RESPIRATORY FAILURE IN A PATIENT WITH HYPEREOSINOPHILIC SYNDROME

SESSION TITLE: Tuesday Medical Student/Resident Case Report Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: 10/22/2019 01:00 PM - 02:00 PM INTRODUCTION: Hypereosinophilic syndrome (HES) is a rare disorder characterized by peripheral blood eosinophilia of 〖1.5 x 10〗ˆ3/μL or higher and evidence of end organ manifestations attributable to the eosinophilia and not otherwise explained in the clinical setting. HES has an unknown prevalence, most often affects people age 20 through 50. Few patients with prolonged eosinophilia develop organ dysfunction that characterizes HES. CASE PRESENTATION: This is the case of a healthy 52-year-old man without history of significant systemic illness who presents with non-productive cough, daily febrile episodes and left upper extremity pain for a period 2 months. On physical examination, lungs are clear upon chest auscultation and left sided axillary pain is elicited upon arm abduction. Initial blood work revealed WBC 〖40.62 x 10〗ˆ3/μL; eosinophil count 〖23.56 x 10〗ˆ3/μL, elevated sedimentation rate 112 mm/hr. Initial diagnosing testing for HES was performed. Complete blood count was remarkable for increasing trend in leukocytes and eosinophils. Routine chemistries, including liver function tests were within normal limits. Quantitative serum immunoglobulin levels, including IgE were normal. Serum troponin, echocardiogram, electrocardiogram, Pulmonary function tests revealed no abnormalities. Bone marrow biopsy including cytogenetics had no myeloproliferative abnormalities. Flexible bronchoscopy with bronchoalveolar lavage revealed eosinophils count less than 3%, no evidence of bacteria, viral or fungal infection. Serology examination for diagnosis of parasitic infection, HIV testing, antineutrophil antibodies ANCA, Serum tryptase and B12 levels, PET scan, lymph node biopsy, EBV viral load were completely negative. The patient’s eosinophilia continued to rise, peaking at 56.00 x 103/μL, despite high-dose prednisone therapy (200 mg by mouth daily), he went in to respiratory failure, cardiac arrest and developed multi organ dysfunction. Hydroxyurea (1 g daily) was added. He improved after the addition of hydroxyurea, and a decrease trending of his eosinophil count was seen. Hydroxyurea was discontinued, and prednisone was tapered. DISCUSSION: HES is a rare heterogeneous disease, any organ system is vulnerable to get affected. The symptoms are common in many other medical problems, making an initial diagnosis more difficult. Sometimes no underlying cause can be found for an observed eosinophilia, even after an extensive diagnostic evaluation. In the absence of an identifiable reactive cause for the eosinophilia, a diagnosis of idiopathic HES can be established if there is evidence of organ involvement and dysfunction. CONCLUSIONS: Our case illustrates the importance of considering diagnosis in patients with significant eosinophilia. Have a high index of suspicion in the background of persistent peripheral eosinophilia; after exclusion of secondary causes. Reference #1: https://doi.org/10.1182/asheducation-2018.1.326 ASH Education Book November 30, 2018 vol. 2018 no. 1 326-331 Reference #2: Klion AD. How I treat hypereosinophilic syndromes. Blood. 2015;126(9):1069-1077. Reference #3: Khoury P, Abiodun AO, Holland-Thomas N, Fay MP, Klion AD. Hypereosinophilic syndrome subtype predicts responsiveness to glucocorticoids. J Allergy Clin Immunol Pract. 2018;6(1):190-195. DISCLOSURES: No relevant relationships by Hector Cintron-Colon, source=Web Response No relevant relationships by Ricardo Fernandez, source=Web Response No relevant relationships by Vanessa Fonseca Ferrer, source=Web Response No relevant relationships by WIlliam Marrero, source=Web Response No relevant relationships by Luis Piñeiro, source=Web Response

The use of a probe stabilizer to reduce musculoskeletal overload of ultrasound operators in routine diagnostic echocardiographic imaging

Introduction: Echocardiography is essential in the evaluation of patients with cardiovascular disease. Repetitive movements, however, expose ultrasound operators to a high risk of musculoskeletal strain injuries. Aim: We investigated to what extent a probe stabilizer could reduce repetitive movements. Materials and methods: The study population consisted of 31 male patients referred for routine transthoracic echocardiography. A good apical acoustic window was prerequisite for inclusion. Standard apical views and measurements were first recorded without using the probe stabilizer. Afterwards, the same apical views and measurements were acquired with utilization of the probe stabilizer. During the entire procedure, shoulder abduction and muscle activity of right forearm flexor and extensor muscles were recorded. To this purpose, an EMG-sensor was attached to the right lower arm and a gyroscope to the right shoulder blade. Results: Extreme right arm abduction (>30˚) occurred in 58% of the time with use of the stabilizer and in 98% of the time without (p <0.01). Activity of right forearm extensor muscles was 42% with and 60% without stabilizer (p = 0.04). For the flexor muscles these percentages were 47% and 87%, respectively (p <0.01). Use of the stabilizer did not affect the time needed for image acquisition (308s versus 309s, respectively, p = 0.46). Conclusions: This study demonstrated that the use of a stabilizer during acquisition of apical views in routine transthoracic echocardiography reduces the total time of shoulder abduction and the use of the right forearm muscles, while acquisition time was not affected.

Internal impingement of the shoulder: An international survey of 261 orthopaedic surgeons

BackgroundInternal impingement of the shoulder (IIS) is a specific disorder of young overhead-throwing athletes that was first described in 1991. The many non-operative and surgical treatments suggested to date have produced mixed outcomes. The objective of this study was to compare the practices of surgeons in France versus other countries regarding the diagnosis and treatment of IIS. HypothesisDiagnostic and therapeutic practices regarding IIS differ between surgeons in France and in other countries. Material and methodsA 21-item questionnaire in French and English was emailed to the 1300 members of the French Arthroscopy Society and to surgeons from countries other than France. The questionnaire collected information on knowledge about IIS (2 items), the frequency of IIS in clinical practice (2 items), the diagnosis of IIS (6 items), the non-operative and surgical treatment of IIS (3 and 5 items, respectively), and return-to-sports rates after treatment for IIS (3 items). ResultsThe completed questionnaire was sent back by 261 surgeons, 206 in France and 55 in other countries, including 42 in Japan. Among the respondents, 90% knew about IIS. Experience with IIS in terms of number of patients seen or surgical treatments performed was greater in the international group (45% vs. 19% in France, p<0.001). Posterior shoulder pain in the arm cocking position was the most widely recognised symptom (99% in France, 74% internationally, p<0.001), followed by excessive external rotation during arm abduction (55% vs. 65%, p=0.23). The most commonly sought lesions were those of the postero-superior labrum and articular surface of the rotator cuff. Rotator cuff debridement was among the surgical options according to most respondents (74% vs. 70%). In contrast, postero-superior glenoidplasty was cited almost only by surgeons in France (67% vs. 4%, p<0.001). The proportion of patients who are able to return to sports was estimated at 50% to 75% by most respondents. DiscussionMost respondents had theoretical knowledge about IIS, but surgery was rarely performed in France. Only very few athletes in France play baseball, which is responsible for most sports injuries of the shoulder seen in Japan. This fact, combined with differences in the lesions or even the diagnoses, may have contributed to the differences in the responses to the survey items between the French and international groups.

Effectiveness of early rehabilitation on range of motion, muscle strength and arm function after breast cancer surgery: a systematic review of randomized controlled trials

Objective: The objective was to evaluate the effectiveness of early rehabilitation on arm range of motion (ROM), strength and function after breast cancer surgery (BCS). Data sources: PubMed, MEDLINE, Bireme, Embase, LILACS and CINAHL databases were searched. Methods: Two independent reviewers selected randomized controlled trials evaluating women who underwent early rehabilitation to restore arm ROM, strength or function after BCS. Cochrane Collaboration recommendations and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Methodological quality was assessed by the PEDro scale. The International Classification of Functioning, Disability and Health was considered to analyze results. Effect size (ES) was calculated for clinical relevance interpretation of the outcomes of interest, and the evidence was summarized through the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Results: Up to June 2019, a total of 1658 references were identified and 15 studies were included. Twelve of them presented adequate methodological quality. A total of 1710 patients were evaluated. Few studies performed the simultaneous assessment of variables related to body structure and function and patient-reported outcomes. A moderate level of evidence was synthesized regarding the effectiveness of ROM exercises for improving arm flexion, abduction and external rotation (ES: 0.45–2.5). A low level of evidence was synthesized regarding the effectiveness of isolated strengthening exercises for patient-reported arm function. ROM exercises associated with muscle strengthening exhibited a moderate level of evidence for improving shoulder flexion (ES: 1.4–2.4). Conclusion: Both ROM and strengthening exercises associated with ROM exercises improved shoulder flexion, abduction and external rotation ROM after BCS. Shoulder abduction and external rotation showed less recovery, irrespective of the intervention applied.

Middle-aged adults cocontract with arm ADductors during arm ABduction, while young adults do not. Adaptations to preserve pain-free function?

Middle-aged individuals cocontract with adductor muscles during abduction. This may be crucial for counteracting deltoid forces, depressing the humerus and ensuring free passage of subacromial tissues underneath the acromion during abduction. We questioned whether adductor co-contraction is always present, or develops during ageing, in which case it may explain the age-related character of common shoulder conditions such as Subacromial Pain Syndrome. In a cross-sectional analysis with electromyography (EMG), activation patterns of the latissimus dorsi, teres major, pectoralis major and deltoid muscle were assessed during isometric force tasks in 60 asymptomatic individuals between 21 and 60 years old. Cocontraction was expressed as the degree of antagonistic activation relative to the same muscle’s degree of agonistic activation, resulting in an activation ratio between −1 and 1, where lower values indicate more cocontraction. Using linear regression analyses, we found age-related decreases in the activation ratio of the latissimus dorsi (regression estimate: −0.004, 95% CI: −0.007 to 0.0, p-value: 0.042) and teres major (regression estimate: −0.013, 95% CI: −0.019 to −0.008, p-value: <0.001). In contrast to young individuals, middle-aged individuals showed a high degree of adductor cocontraction during abduction. This may indicate that during ageing, alterations in activation patterns are required for preserving pain-free shoulder function.

Visual estimation of shoulder posture: accuracy and reliability across five planes of motion

Background: Visual estimation is still widely used by physiotherapists in clinical practice. The accuracy and reliability of visual estimation are under question and vary with the joint being evaluated. The utility of using visual estimation to evaluate shoulder angular posture is inconclusive and has yet to be evaluated across a comprehensive range of planes and postures.Objective: The purpose of this observational, cross-sectional study was to determine whether visual estimation is an accurate and reliable procedure for determining shoulder angular postures in a range of shoulder motions.Methods: Sixty-three physical therapy students viewed digital photographs of an asymptomatic volunteer to visually estimate degrees of arm abduction, flexion, extension, internal rotation, and external rotation. Six photographs from each plane of movement were shown, at positions spanning the available range of motion, and participants were asked to estimate the angular posture. Estimates were averaged, and errors from computer measurements were calculated. Differences between estimates and measurements were determined with t-tests.Results: The overall accuracy of the visual estimates is considered poor to fair. Root mean square errors were reasonable, from 5° to 17°, but the 95% spread of the data reached a maximum of 53°. Estimates were most accurate at the abduction and flexion postures closest to 90°. Most estimates for extension were underestimated, while more internal rotation estimates were overestimated. Reliability ranged from poor to fair (0.12–0.63).Conclusions: Using visual estimation to evaluate shoulder planar postures results in a wide range of error. Physiotherapy students should be encouraged to use more objective measurement methods.

In Which Arm Position Is a Hill-Sachs Lesion Created?

Background: It has been believed that a Hill-Sachs lesion (HSL) is created with the arm in abduction and external rotation at the time of dislocation. However, no studies have clarified the arm position in which an HSL is created. Purpose: To determine the arm position in which an HSL is created. Study Design: Descriptive laboratory study. Methods: The computed tomography images of 100 shoulders of 100 patients (72 males and 28 females; mean age, 30 years old) with recurrent anterior dislocation of the shoulder were investigated using an image analyzing software. Three-dimensional surface bone models of the scapula and humerus were created separately. The humerus was moved so that the HSL perfectly fit the anterior rim of the glenoid. This arm position was recorded 3-dimensionally. Results: Considering the scapulohumeral rhythm, the average arm position in which the HSL and the anterior glenoid rim best fit was 74° of abduction, 27° of external rotation, and 3° of horizontal flexion relative to the trunk. Conclusion: The arm position when an HSL and the anterior glenoid rim best fit is 74° of abduction, 27° of external rotation, and 3° of horizontal flexion, which seems to be the arm position when the HSL has been created. This result suggests 2 possibilities: dislocation occurred in this midrange position or HSL was not created at the time of dislocation but later in the mid–range of motion. However, as we have no information on the arm position at the time of dislocation, we cannot conclude which of these possibilities is true in our study. Clinical Relevance: This study gives us a better understanding of the timing of HSL occurrence. Shoulder dislocation may occur at the end range of motion or in the mid–range of motion, but an HSL is created in the mid–range of motion.