Shoulder Elevation Research Articles

Pseudoparalysis and pseudoparesis of the shoulder

Abstract Background Clinical presentation of massive rotator cuff tears range from pain to loss of active range of motion. Pseudoparalysis and pseudoparesis are defined inconsistently in the literature, but both include limited active with maintained passive range of motion. Objective This article aims to provide a consistent definition of pseudoparalysis and pseudoparesis of the shoulder and show structural and biomechanical differences between these two types of rotator cuff tear with their implications for treatment. Methods A literature review including key and basic papers discussing clinical symptoms, biomechanical differences, and their impact on therapeutic options for pseudoparalysis and pseudoparesis was performed. Results Biomechanically, structural differences between pseudoparalysis (active scapular plane abduction <45°) and pseudoparesis (active scapular plane abduction 45–90°) exist. For massive posterosuperior rotator cuff tears, the integrity of the inferior subscapularis tendon is the most predictive factor for active humeral elevation. Patients with pseudoparalysis have a higher grade of subscapularis tendon involvement (>50%) and fatty infiltration of the subscapularis muscle. Treatment options depend on the acuteness and repairability of the tear. Rotator cuff repair can reliably reverse the active loss of active range of motion in acute and reparable rotator cuff tears. In chronic and irreparable cases reverse total shoulder arthroplasty is the most reliable treatment option in elderly patients. Conclusion The most concise definition of pseudoparalysis is a massive rotator cuff tear that leads to limited active (<45° shoulder elevation) with free passive range of motion in the absence of neurologic deficits as the reason for loss of active elevation. The integrity of the subscapularis tendon is the most important difference between a pseudoparalytic and pseudoparetic (active shoulder elevation 45–90°) shoulder. Decision-making for surgical options depends more on reparability of the tendon tear and patient age than on differentiation between pseudoparalysis and pseudoparesis.

The impact of experimental pain on shoulder movement during an arm elevated reaching task in a virtual reality environment.

BackgroundPeople with chronic shoulder pain have been shown to present with motor adaptations during arm movements. These adaptations may create abnormal physical stress on shoulder tendons and muscles. However, how and why these adaptations develop from the acute stage of pain is still not well‐understood.ObjectiveTo investigate motor adaptations following acute experimental shoulder pain during upper limb reaching.MethodsForty participants were assigned to the Control or Pain group. They completed a task consisting of reaching targets in a virtual reality environment at three time points: (1) baseline (both groups pain‐free), (2) experimental phase (Pain group experiencing acute shoulder pain induced by injecting hypertonic saline into subacromial space), and (3) Post experimental phase (both groups pain‐free). Electromyographic (EMG) activity, kinematics, and performance data were collected.ResultsThe Pain group showed altered movement planning and execution as shown by a significant increased delay to reach muscles EMG peak and a loss of accuracy, compared to controls that have decreased their mean delay to reach muscles peak and improved their movement speed through the phases. The Pain group also showed protective kinematic adaptations using less shoulder elevation and elbow flexion, which persisted when they no longer felt the experimental pain.ConclusionAcute experimental pain altered movement planning and execution, which affected task performance. Kinematic data also suggest that such adaptations may persist over time, which could explain those observed in chronic pain populations.

Scapular Dyskinesis, Shoulder Joint Position Sense, and Functional Level After Arthroscopic Bankart Repair.

Background:Scapular kinesia is an important component of glenohumeral rhythm and shoulder stability. No studies have evaluated scapular dyskinesis and its relationship to shoulder proprioception in patients who have undergone arthroscopic Bankart repair (ABR).Purpose:To investigate scapular dyskinesis, proprioception, and functional level after ABR.Study Design:Cohort study; Level of evidence, 3.Methods:This study included 13 male patients who underwent ABR (ABR group; mean age, 30 years; range, 24-36 years) and 13 sex- and age-matched healthy individuals (control group). The age, height, weight, and dominant side of all participants were collected. Scapular dyskinesis was evaluated using the lateral scapular slide test and the scapular dyskinesis test; proprioception was measured by the active angle reproduction test using a smartphone goniometer application, and functional level was assessed using the upper-quarter Y-balance test for dynamic stability as well as the Rowe score and Walch-Duplay score for quality of life and return to activities of daily living.Results:The presence of static scapular dyskinesis in the neutral position, at 45° of abduction, and at 90° of abduction as well as the presence of dynamic scapular dyskinesis was higher in the ABR group compared with the control group (P ≤ .04 for all). Shoulder joint position sense (absolute error) at 40° and 100° of shoulder elevation and shoulder functional level according to the Rowe score were worse in the ABR patients compared with the healthy controls (P ≤ .02 for all). Dynamic scapular dyskinesis was negatively related to shoulder joint position sense at 40° of shoulder elevation (r = –0.64; P = .01). Static scapular movement as measured on the lateral scapular slide test was moderately related to the Rowe score (r = 0.58; P = .03).Conclusion:Scapular kinematics and proprioception should be evaluated after ABR. Treatment approaches to improve scapular control and proprioceptive sense should be included in the rehabilitation program for patients after ABR.

Fatigue, Stress, and Performance during Alternating Physical and Cognitive Tasks-Effects of the Temporal Pattern of Alternations.

In occupational life, performing cognitive work tasks in between fatiguing physical work tasks may allow recovery and reduce stress without losing productive working time. The temporal pattern of such alternations is likely a determinant of the recovery effect, influencing both stress and fatigue; the difficulty of the cognitive task (CT) would also be a likely determinant. The aim of this study was to determine to what extent the temporal pattern of alternations between a repetitive physical task and a CT of different difficulties influenced perceived fatigability, performance fatigability, stress-related outcomes, and performance. Fifteen women performed four work sessions comprising 110 min of repeated bouts of a repetitive physical task (pipetting), alternating with a CT (n-back). Sessions differed in bout cycle time (short: 7 + 3 min versus long: 14 + 6 min) and CT difficulty (CTdiff; easy versus difficult). Fatigue was assessed from recordings of maximal voluntary contraction force in shoulder elevations and handgrip pre- and post-work, electromyography (EMG) from the right trapezius and right forearm extensors during work, and repeated self-ratings of fatigue and pain throughout the session. Stress was assessed using electrocardiography (heart rate variability), salivary alpha-amylase, and self-reports. Perceived fatigue increased significantly over time for all protocols and more in long-cycle than short-cycle conditions. EMG activity did not increase markedly over time in any condition. Neither objective nor subjective indicators suggested that stress increased over time, regardless of the temporal pattern. Pipetting performance remained stable in all conditions. Cognitive performance, measured by the proportions of correct positive and false positive answers, differed between CTdiff levels but remained stable over time, with no significant difference between temporal patterns. In summary, temporal patterns of alternating tasks influenced fatigue to some extent but had no obvious influence on stress indicators or performance. Thus, designing job rotation with alternating physical and cognitive work should consider the temporal patterns of alternations to minimize fatigue.

Whole-body kinematics during a simulated sprint in flat-water kayakers

ABSTRACT Success in sprint kayaking depends on the propulsive power generated by trunk, pelvis, shoulder and lower limb movements. However, no studies have examined whole-body kinematics over a simulated distance. We aimed to study the changes in movement patterns of kayakers performing a 500-m kayak sprint. Eleven young K1 sprint kayakers (three females; age: 16.5 ± 1.9 years, height: 174.1 ± 7.1 cm and weight: 66.1 ± 6.2 kg) performed an incremental test on a kayak ergometer to assess their Peak Oxygen Uptake (V̇O2peak). They then performed a 500-m sprint trial on the same ergometer, and the positions of 40 reflective markers were recorded to assess whole-body kinematics. Joint angles over time were computed for the trunk and right shoulder, hip, knee, and ankle. Changes of joint kinematics during the test were assessed with Statistical Parametric Mapping, calculating at each time node the linear regression between joint angles waveforms and the time of the rowing cycle, p < .05. Cardiometabolic responses confirmed that the participants achieved a maximal effort (V̇O2 and HR reached 99 ± 11% and 94 ± 6% of peak values, respectively). Paddle velocity negatively correlated with sprint time. The shoulder (elevation, rotation and flexion), trunk (lateral flexion and rotation) and hip (abduction) angles significantly changed over time in different phases of the stroke cycle during the simulated sprint. No significant differences over time were found for knee and ankle flexion. A high-intensity sprint may affect the shoulder, trunk and hip kinematics of kayak paddling. The kinematic analysis of kayakers’ paddling during simulated metabolic-demanding tasks can provide useful insights to coaches and athletes.

Effect of Handrail Height and Age on Trunk and Shoulder Kinematics Following Perturbation-Evoked Grasping Reactions During Gait.

To characterize the effect of handrail height and age on trunk and shoulder kinematics, and concomitant handrail forces, on balance recovery reactions during gait. Falls are the leading cause of unintentional injury in adults in North America. Handrails can significantly enhance balance recovery and help individuals to avoid falls, provided that their design allows users across the lifespan to reach and grasp the rail after balance loss, and control their trunk by applying hand-contact forces to the rail. However, the effect of handrail height and age on trunk and shoulder kinematics when recovering from perturbations during gait is unknown. Fourteen younger and 13 older adults experienced balance loss (sudden platform translations) while walking beside a height-adjustable handrail. Handrail height was varied from 30 to 44 inches (76 to 112 cm). Trunk and shoulder kinematics were measured via 3D motion capture; applied handrail forces were collected from load cells mounted to the rail. As handrail height increased (up to 42 inches/107 cm), peak trunk angular displacement and velocity generally decreased, while shoulder elevation angles during reaching and peak handrail forces did not differ significantly between 36 and 42 inches (91 and 107 cm). Age was associated with reduced peak trunk angular displacements, but did not affect applied handrail forces. Higher handrails (up to 42 inches) may be advantageous for trunk control when recovering from destabilizations during gait. Our results can inform building codes, workplace safety standards, and accessibility standards, for safer handrail design.

Biomechanics of an Accessory Clavicular Head to the Sternocleidomastoid Muscle: Cadaveric Case and 3D Modeling

Introduction & Objective The sternocleidomastoid (SCM) is a muscle of the head and neck. Its sternal (SH) and clavicular (CH) heads ascend the neck, merge, and insert on the skull. An accessory clavicular head (ACH) can develop from a remnant slip of the trapezius when the SCM and trapezius separate from the same embryological muscle mass. Variations in gross presentation of accessory SCM heads have been well documented, but their mechanics are less described and the literature could benefit from 3D modeling of a SCMACH. The objective of this study is to examine a case of bilateral SCMACH on a human cadaver and calculate its biomechanical capacity through direct measurements and 3D modeling. Materials & Methods Bilateral SCMs with ACHs were dissected, eviscerated, and photographed (iPad Pro, Apple, Inc.). Image color contrast was utilized to aide structure identification (Adobe Photoshop 20.0.9). Muscles, fascicle bundles, attachments, and pennation angles were measured (ImageJ, 1.52q) before removing and weighing each muscle belly (Ohaus Scale, Model V22PWE1501T). Each head's physiological cross-sectional area (PCSA) was calculated and multiplied by an accepted specific tension value for fast-acting skeletal muscle (22.5 N cm-2) to determine their theoretical maximal isometric forces (MIF) of contraction. MIFACH was compared to MIFSH,CH and considered for its mechanical effect on clavicle and skull movements. All calculations were derived from mean values between the bilateral SCM heads. 3D modeling is in process and will be used to determine angles and force vectors created by SCMACH on the clavicle and skull. Additionally, electron microscopy imaging is in process to evaluate SCMACH sarcomere state. Results The SCMACH had a mass of 3.41 grams and measured 16.8 cm in total length. Its muscle fibers were parallel and composed 15.8 cm (94.0%) of the muscle's total length. Its 3.0 cm wide origin attached to the clavicle 5.6 cm lateral to the sternoclavicular joint, and it inserted with the SCMSH,CH on the mastoid process and superior nuchal line. The PCSA of the SCMSH, SCMCH, and SCMACH was 1.02 cm2, 0.54 cm2, and 0.20 cm2, generating MIFs of 23.03 N, 12.04 N, and 4.59 N, respectively. In this regard, the MIFACH would have increased the force of the normal SCMSH,CH on the skull by 13.1%. Compared to the MIFCH alone, the MIFACH would exert 38.1% more force on the clavicle at a more distal location from the clavicle's fulcrum than SCMCH. Conclusions & Significance Presence of a SCMACH can generate considerably more force on the distal clavicle and posteroinferior skull than normal. This additional capacity to the normal SCM could assist in shoulder elevation, ipsilateral neck flexion, contralateral head rotation as well as help maintain static support and position of the pectoral girdle and neck/head. Alternatively, it could decrease access to neurovascular structures of the neck, complicate physical examination and radiologic imaging, and impact fractures of the clavicle. The force vectors acting on the pectoral girdle are dimensionally complex, so 3D modeling and biomechanical analysis is necessary for a complete investigation. The gross imaging, 3D modeling, and biomechanics of the SCMACH presented in this study may help clinicians with diagnoses, procedures, and treatments pertaining to the head and neck.

Dissociating Sensorimotor Recovery and Compensation During Exoskeleton Training Following Stroke.

The quality of arm movements typically improves in the sub-acute phase of stroke affecting the upper extremity. Here, we used whole arm kinematic analysis during reaching movements to distinguish whether these improvements are due to true recovery or to compensation. Fifty-three participants with post-acute stroke performed ∼80 reaching movement tests during 4 weeks of training with the ArmeoSpring exoskeleton. All participants showed improvements in end-effector performance, as measured by movement smoothness. Four ArmeoSpring angles, shoulder horizontal (SH) rotation, shoulder elevation (SE), elbow rotation, and forearm rotation, were recorded and analyzed. We first characterized healthy joint coordination patterns by performing a sparse principal component analysis on these four joint velocities recorded during reaching tests performed by young control participants. We found that two dominant joint correlations [SH with elbow rotation and SE with forearm rotation] explained over 95% of variance of joint velocity data. We identified two clusters of stroke participants by comparing the evolution of these two correlations in all tests. In the “Recoverer” cluster (N = 19), both joint correlations converged toward the respective correlations for control participants. Thus, Recoverers relearned how to generate smooth end-effector movements while developing joint movement patterns similar to those of control participants. In the “Compensator” cluster (N = 34), at least one of the two joint correlations diverged from the corresponding correlation of control participants. Compensators relearned how to generate smooth end-effector movements by discovering various new compensatory movement patterns dissimilar to those of control participants. New compensatory patterns included atypical decoupling of the SE and forearm joints, and atypical coupling of the SH rotation and elbow joints. There was no difference in clinical impairment level between the two groups either at the onset or at the end of training as assessed with the Upper Extremity Fugl-Meyer scale. However, at the start of training, the Recoverers showed significantly faster improvements in end-effector movement smoothness than the Compensators. Our analysis can be used to inform neurorehabilitation clinicians on how to provide movement feedback during practice and suggest avenues for refining exoskeleton robot therapy to reduce compensatory patterns.

Fitness Policies Within the Fire Service: A Pilot Investigation of Exercise Adherence on Fitness Outcomes Among Rural Firefighters.

The purpose of this study was to investigate the adherence to departmental fitness policies and to evaluate the impact of on-duty firefighters' adherence to fitness outcomes. This cross-sectional designed study utilized a convenience sample of 40 career firefighters from one department in rural southeast Georgia. Onsite gym attendance logs were recorded during a 10-month period. Firefighters were classified as lowest (0-16 sessions), low (17-30 sessions), moderate (31-44 sessions), or high (45+ sessions) adherence for analyses based on gym attendance. The fitness outcomes were retrieved from required annual fitness testing, including measurements of muscular strength (1RMest leg press and 1RMest bench press), muscular endurance (pushup), muscle power (vertical jump), cardiovascular fitness (submaximal treadmill), mobility (functional movement screen), and flexibility (shoulder elevation). Only 12.5% (n = 5) of firefighters complied with the department's fitness policy of a minimum 75% adherence rate. Furthermore, there were significant differences (P ≤ .05) between various muscular strength, endurance, and flexibility between adherence rates. This study indicated that firefighters that complied more with the fitness policies were more physically fit than those that did not. Considerations should be made to promote and enforce departmental fitness policies to ensure that firefighters can physically perform their responsibilities.

Sensing and Control of a Multi-Joint Soft Wearable Robot for Upper-Limb Assistance and Rehabilitation

In the field of wearable robotics, there has been increased interest in the creation of soft wearable robots to provide assistance and rehabilitation for those with physical impairments. Compared to traditional robots, these devices have the potential to be fully portable and lightweight, a flexibility that may allow for increased utilization time as well as enable use outside of a clinical environment. In this letter, we present a textile-based multi-joint soft wearable robot to assist the upper limb, in particular shoulder elevation and elbow extension. Before developing a portable fluidic supply system, we leverage an off-board actuation system for power and control, with the worn components weighting less than half kilogram. We showed that this robot can be mechanically transparent when powered off, not restricting users from performing movements associated with activities of daily living. Three IMUs were placed on the torso, upper arm and forearm to measure the shoulder and elbow kinematics. We found an average RMSE of ~ 5 degrees when compared to an optical motion capture system. We implemented dynamic Gravity Compensation (GC) and Joint Trajectory Tracking (JTT) controllers that actively modulated actuator pressure in response to IMU readings. The controller performances were evaluated in a study with eight healthy individuals. Using the GC controller, subject shoulder muscle activity decreased with increasing magnitude of assistance and for the JTT controller, we obtained low tracking errors (mean ~ 6 degrees RMSE). Future work will evaluate the potential of the robot to assist with activities in post-stroke rehabilitation.

Pilot Study: Physical Examination Evidence of Acupuncture Principal Meridian Coupling.

Objective: This pilot study of acupuncture primary channel coupling examined the effect of anterior tibialis (AT) muscle activation (Stomach = ST channel distribution muscle) on ipsilateral anterior deltoid shoulder elevation strength (Large Intestine = LI channel distribution muscle). Design: Pilot study: prospective before and after trial, nonblinded. Materials and Methods: Twenty healthy adults ages 20-60 years without shoulder pathology were recruited from our institution. All subjects consented with the IRB-approved minimal risk protocol for this study. Average shoulder elevation break strength (kg) with arm elevated 90° from side was measured by dynamometer over 3 trials for each of 4 conditions: standing (baseline), standing with ipsilateral AT activation, seated with legs dangling ipsilateral AT activation, and seated with legs dangling ipsilateral gastrocsoleus (GS) activation. The main outcome measures were percentage decrement in shoulder elevation strength in AT and GS conditions compared with baseline. Paired t-test with a statistical significance alpha level of 0.05 was used for all statistical analyses. Results: A statistically and clinically significant 9.5%-12.5% (P < 0.001) decrease in shoulder elevation strength was found with ipsilateral AT activation whether in the standing or seated position. Reciprocal inhibition of the AT muscle through GS activation in the seated position produced markedly smaller 3%-4% decreases in shoulder elevation strength from baseline. Conclusions: This study provides quantitative physical examination evidence of LI-ST channel coupling, demonstrating a statistically (P < 0.001) and clinically significant decrement in shoulder elevation strength (9.5%-12.5%) with ipsilateral AT activation. These findings support the acupuncture concept of primary channel coupling, with results suggesting a neural basis for these results rather than from a fascial signaling mechanism.

EMG activity of the serratus anterior and trapezius muscles during elevation and PUSH UP exercises

BackgroundElevation and push up (Pu) exercises are considered to be beneficial for the rehabilitation of shoulder complex pathology. Despite their clinical utility, there is a lack of evidence comparing scapulothoracic muscles recruitment during these exercises. ObjectiveTo evaluate the EMG activity of upper trapezius (UT), Lower Trapezius (LT), Upper Serratus anterior (USa) and Lower Serratus anterior (LSa) muscles during a variety of elevation and Pu exercises. MethodsThirteen healthy participants (non, athlete, male, mean ± standard deviation; age: 21.1 ± 1.8 years; height: 1.80 m ± 0.04; weight: 79 ± 12 kg) were assessed. EMG data was collected during Scaption, wall slide and elevation with external rotation (EleEr) with and without load. Pu classic, Pu plus (PuP) on stable/unstable surfaces and Pu with shoulder internal rotation were also assessed. ResultsUT had a significant higher activity during ‘Scaption load’ (p < .05) and LT in ‘EleEr load’ and ‘Scaption load’ (p < .05). USa and LSa had a significant higher activity on ‘PuP unstable surface’ and ‘PuP internal rotation’ compared to elevation exercises (p < .05). Scaption had greater activity ratio compared to the other exercises on UT/LT (p < .05). Pu variations had lower results in UT/USa and UT/LSa ratios compared to shoulder elevation exercises (p < .05). ConclusionsElevation exercises produce significant effects on upper and lower trapezius activation while Pu exercises on Sa muscles. Wall slide exercise notes the lowest activation in all muscles. A descending order of muscle activity during different variations of elevation and Pu exercises is provided in order to guide exercise selection in everyday clinical practice.

Kinetic and kinematic determinants of shuttlecock speed in the forehand jump smash performed by elite male Malaysian badminton players

ABSTRACT Badminton is the fastest racket sport in the world with smash speeds reaching over 111 m/s (400 kph). This study examined the forehand jump smash in badminton using synchronised force plates and full-body motion capture to quantify relationships to shuttlecock speed through correlations. Nineteen elite male Malaysian badminton players were recorded performing forehand jump smashes with the fastest, most accurate jump smash from each player analysed. The fastest smash by each participant was on average 97 m/s with a peak of 105 m/s. A correlational analysis revealed that a faster smash speed was characterised by a more internally rotated shoulder, a less elevated shoulder, and less extended elbow at contact. The positioning of the arm at contact appears to be critical in developing greater shuttlecock smash speeds. Vertical ground reaction force and rate of force development were not correlated with shuttlecock speed, and further investigation is required as to their importance for performance of the jump smash e.g., greater jump height and shuttle angle. It is recommended that players/coaches focus on not over-extending the elbow or excessively elevating the upper arm at contact when trying to maximise smash speed.

Analysis of Preoperative and Operative Factors Influencing Postoperative Shoulder Imbalance in Lenke Type 1 Adolescent Idiopathic Scoliosis.

Postoperative shoulder imbalance is a common complication in adolescent idiopathic scoliosis and may impair patient satisfaction. The little data in the literature on the prediction and treatment of postoperative shoulder imbalance is incongruous. According to some studies, postoperative shoulder imbalance depends on the superior instrumented vertebral bodies, skeletal maturity, extent of correction and flexibility of the major curve. Can preoperative radiological parameters from X-ray and traction films as well as correction of the curves be used to identify a factor impacting on postoperative shoulder imbalance? Prospective data in adolescent idiopathic scoliosis with thoracic curve (Lenke type 1), operated on between 2015 and 2018 at a scoliosis centre, were analysed retrospectively based on full-length X-rays of the spine (pre-/postOP and follow-up (FU)) and preoperative-traction films: age; correction of proximal, main and lumbar curve; shoulder height [mm]; clavicle angle [°]; T1 tilt [°]; coronal plumb line deviation [mm]. The findings were expressed as means with standard deviation. Changes in parameters over time (postOP-FU) were compared by t test (significance level α = 0.05). The correlation between preOP parameters and extent of correction with postoperative shoulder imbalance (≥ 15 mm) was determined by Pearson correlation and regression classification analysis. 55 patients with adolescent idiopathic scoliosis, mean age of 15 ± 1.4 years. The FU-rate after a mean of 15 months was 80% (n = 44). Correction of proximal, main and lumbar curve: 47.0%, 75.8% and 68.8%, respectively, without statistically significant change (Δ) in FU (p > 0.05). Shoulder height was - 11.0 ± 12.7 mm (preOP), 15.5 ± 13.4 mm (postOP), 10.1 ± 10.6 mm (FU) (p < 0.05). 38% of those with adolescent idiopathic scoliosis had preOP right shoulder elevation; 55% (postOP) and 32% (FU) respectively had postoperative shoulder imbalance (left shoulder elevation). Strong statistical correlation was found for Δshoulder position (FU-preOP) with pre-OP shoulder position (r = - 0.7), and Δshoulder position (pre-OP traction films) (r = 0.5) with pre-OP clavicle angle (r = - 0.5). On regression classification analysis, 81.8% of cases did display postoperative shoulder imbalance if proximal curve correction was ≤ 64.4%; main and lumbar curve correction, Δshoulder elevation (preOP traction films) played a secondary role. One common complication even in Lenke type 1 adolescent idiopathic scoliosis is postoperative shoulder imbalance. Preoperative planning should include traction films, preoperative shoulder position and clavicle angle to avoid postoperative shoulder imbalance. Moderate correction of proximal curve is critical for postoperative shoulder balance.

Shoulder Joint Position Sense Can Be Reduced by Sensory Reference Frame Transformations.

Joint position sense (JPS) is commonly evaluated using an angle replication protocol with vision occluded. However, multiple sources of sensory information are integrated when moving limbs accurately, not just proprioception. The purpose of this study was to examine different availability of vision during an active JPS protocol at the shoulder. Specifically, the effects of four conditions of vision availability were examined for three target shoulder elevation angles (50°, 70° & 90°): vision occluded continuously (P-P); vision available continuously (VP-VP); vision occluded only during target memorization (P-VP); and vision occluded only during target position replication (VP-P). There were 18 participants (M age = 21, SD = 1 years). We used separate repeated ANOVAs to examine the effect of condition and target angle on participants' absolute error (AE, a measure of accuracy) and constant error (CE, a measure of directional bias). We found a significant main effect for condition and angle for both dependent variables (p < 0.01), and follow-up analysis indicated that participants were most accurate in the VP-VP condition and least accurate in the P-VP condition. Further follow-up analysis showed that accuracy improved with higher target elevation angles, consistent with previous research findings. Constant error results were similar, as there was a prominent tendency to overshoot the target. Unsurprisingly, participants performed best at the angle replication protocol with their eyes open. However, while accuracy was reduced when vision was occluded during target memorization, it was restored during target replication. This finding may have indicated an accuracy cost due to introduced noise when transforming sensory information from a proprioceptive reference frame into a visual reference frame.

The clinical outcomes and tuberosity healing after reverse total shoulder arthroplasty for acute proximal humeral fracture using the turned stem tension band technique

BackgroundRecent studies have reported the clinical effectiveness of tuberosity healing after reverse total shoulder arthroplasty in patients with proximal humeral fractures with respect to joint stability, long-term survival, and postoperative range of motion. However, it is challenging to achieve robust fixation of the fragile bone fragments in elderly patients. This study aimed to report on the radiographic and clinical outcomes of patients who underwent reverse total shoulder arthroplasty for acute proximal humeral fractures using a Turned stem Tension Band technique–a simple suture configuration that can apply a compressive force on both tuberosities at the same time. MethodsEighteen patients who underwent reverse total shoulder arthroplasty for complex proximal humeral fractures (age 80.4 ± 4.7 years, range 70–87 years), using our Turned stem Tension Band technique, were included in this study and evaluated postoperatively for range of motion, American Shoulder and Elbow Surgeons score, Numerical Rating Scale, and tuberosity healing, with minimum 2-years follow-up (mean 34.5 months, range 24–60 months). ResultsAt the final follow-up, mean range of motion results were active flexion, 119 ± 34°; active abduction, 116 ± 35°; active external rotation, 27 ± 12°; and active internal rotation, L3. Six of 11 (55%) patients with 4-part dislocated fractures had neurological disorders from the time of injury; of these, three patients obtained shoulder elevation under 90° at the final follow-up. The mean American Shoulder and Elbow Surgeons score was 77.3 ± 10.7, and the mean Numerical Rating Scale was 1.2 ± 0.9. Fifteen of 18 (83%) patients were satisfied with the results. The tuberosity healing rate was 100% (18 of 18). ConclusionsThe Turned stem Tension Band technique in reverse total shoulder arthroplasty for proximal humeral fractures provides a robust fixation, regardless of the fracture pattern, which results in a high tuberosity healing rate.

Comparison of thoracoscopy vs. thoracotomy on musculoskeletal outcomes of children with congenital pulmonary airway malformation (CPAM)

Background: It has been postulated that video-assisted thoracoscopic surgery (VATS) is superior than conventional thoracotomy for resection of congenital pulmonary airway malformation (CPAM) in terms of shorter hospital length of stay, reduced post-operative complication and better long-term pulmonary outcome. However, there is limited available data concerning the effect of VATS and conventional thoracotomy on musculoskeletal aspects in patients with CPAM. This study aims to compare the long-term effects of both surgical techniques on musculoskeletal outcomes in this group of patients.Methods: Thirty-five patients with mean age of 11.38 years old who underwent VATS or conventional thoracotomy for CPAM resection were recruited in this study. The mean follow-up time was 10.42 years (5.48 to 17.71 years). Musculoskeletal examination included screening of musculoskeletal deformities (elevation of shoulder, asymmetry of nipple level, breast/ pectoral muscle maldevelopment, winging of scapula, scoliosis), measurement of bilateral chest wall in relation to anatomical parameter, and testing of shoulder range of motion and power.Results: The prevalence of winged scapula was significantly lower in patients who underwent VATS than thoracotomy (13% vs 58%, p = 0.008). There is also a smaller reduction in operated-side chest wall vertical distance in VATS patients (0.982 vs 0.956, p = 0.058). There were no significant difference in prevalence of other musculoskeletal deformities, other chest wall measurements, shoulder range of motion and power between two groups.Conclusion: Thoracoscopy decreases the incidence of scapular winging but has no effect on effect on other musculoskeletal deformities.

Assessment of alternative methods for informal caregivers to perform patient repositioning tasks

Manual patient handling tasks put formal and informal caregivers at risk of musculoskeletal injury. Intervention research to reduce risks to informal caregivers is limited. This study examined effects of slide sheet use when individual informal caregivers performed patient boosting and turning tasks. Three methods of slide sheet use and a baseline method (no slide sheet) were compared, to reposition a 70 kg individual. Muscle activity, ground reaction force, posture, and rating of perceived exertion were significantly affected by task method. Erector Spinae activity was reduced in boosting and turning away tasks with the slide sheet. Shoulder elevation, torso angle, and normalized vertical ground reaction force were also reduced with the slide sheet during boosting. The turn towards task was generally not improved with the slide sheet. Overall, using a slide sheet provided biomechanical benefits to individual caregivers performing two common patient handling tasks: boosting and turning patient away from caregiver.

Dynamic Ultrasonographic Evaluation of the Scapulohumeral Joint during Shoulder Elevation

Dynamic Ultrasonographic Evaluation of the Scapulohumeral Joint during Shoulder Elevation

Does Margin Convergence Reverse Pseudoparalysis in Patients with Irreparable Rotator Cuff Tears?

Margin convergence has been shown to restore muscle tension in a cadaveric model of a rotator cuff tear. However, the clinical utility of this technique remains uncertain for patients with pseudoparalysis caused by an irreparable rotator cuff tear. (1) For patients with massive irreparable rotator cuff tears, in what proportion of patients does margin convergence reverse pseudoparalysis? (2) In patients with massive irreparable rotator cuff tears, does margin convergence improve American Shoulder and Elbow Surgeons (ASES) scores? (3) What is the survivorship free from MRI evidence of retear after margin convergence? Between 2000 and 2015, we treated 203 patients for pseudoparalysis with a rotator cuff tear. Pseudoparalysis was defined as active elevation less than 90° with no stiffness, which a physical therapist evaluated in the sitting position using a goniometer after subacromial injection of 10 cc lidocaine to eliminate pain. Of those, we considered patients who underwent at least 3 weeks of unsuccessful nonoperative treatment in our hospital as potentially eligible. Twenty-one percent (43 of 203) who either improved or were lost to follow-up within 3 weeks of nonoperative treatment were excluded. A further 12% (25 of 203) were excluded because of cervical palsy, axillary nerve palsy after dislocation or subluxation, and development of severe shoulder stiffness (passive shoulder elevation < 90°). Repair was the first-line treatment, but if tears were considered irreparable with the torn tendon unable to reach the original footprint after mobilizing the cuff during surgery, margin convergence was used. When margin convergence failed, the procedure was converted to hemiarthroplasty using a small humeral head to help complete the repair. Therefore, 21% (42 of 203) of patients treated with regular repair (18% [36 of 203]) or hemiarthroplasty (3% [6 of 203]) were excluded. That left 93 patients eligible for consideration. Of those, 13 patients were lost before the minimum study follow-up of 2 years or had incomplete datasets, and 86% (80 of 93) were analyzed (49 men and 31 women; mean age 68 ± 9 years; mean follow-up 26 ± 4 months). Seventy-six percent (61 of 80) were not evaluated in the last 5 years. We considered reversal of pseudoparalysis as our primary study outcome of interest; we defined this as greater than 90° active forward elevation; physical therapists in care measured this in the sitting position by using goniometers. Clinical outcomes were evaluated based on the ASES score from chart review, active ROM in the shoulder measured by the physical therapists, and the 8-month Kaplan-Meier survivorship free from MRI evidence of retear graded by the first author. Pseudoparalysis was reversed in 93% (74 of 80) patients, and improvement in ASES scores was observed at the final follow-up (preoperative 22 ± 10 to postoperative 62 ± 21, mean difference 40 [95% CI 35 to 45]; p < 0.01). The 8-month Kaplan-Meier survivorship free from MRI evidence of retear after surgery was 72% (95% CI 63% to 81%). There were no differences in clinical scores between patients with and without retears (intact ASES 64 ± 24, re-tear ASES 59 ± 10, mean difference 6 [95% CI -5 to 16]; p = 0.27). Margin convergence can be a good option for treating patients with pseudoparalysis and irreparable rotator cuff tears despite the relatively high retear rates. The proportion of pseudoparalysis reversal was lower in patients with three-tendon involvement. Further studies will be needed to define the appropriate procedure in this group. Level IV, therapeutic study.