Characterization of stroke-related upper limb motor impairments across various upper limb activities by use of kinematic core set measures

Background Upper limb kinematic assessments provide quantifiable information on qualitative movement behavior and limitations after stroke. A comprehensive characterization of spatiotemporal kinematics of stroke subjects during upper limb daily living activities is lacking. Herein, kinematic expressions were investigated with respect to different movement types and impairment levels for the entire task as well as for motion subphases. Method Chronic stroke subjects with upper limb movement impairments and healthy subjects performed a set of daily living activities including gesture and grasp movements. Kinematic measures of trunk displacement, shoulder flexion/extension, shoulder abduction/adduction, elbow flexion/extension, forearm pronation/supination, wrist flexion/extension, movement time, hand peak velocity, number of velocity peaks (NVP), and spectral arc length (SPARC) were extracted for the whole movement as well as the subphases of reaching distally and proximally. The effects of the factors gesture versus grasp movements, and the impairment level on the kinematics of the whole task were tested. Similarities considering the metrics expressions and relations were investigated for the subphases of reaching proximally and distally between tasks and subgroups. Results Data of 26 stroke and 5 healthy subjects were included. Gesture and grasp movements were differently expressed across subjects. Gestures were performed with larger shoulder motions besides higher peak velocity. Grasp movements were expressed by larger trunk, forearm, and wrist motions. Trunk displacement, movement time, and NVP increased and shoulder flexion/extension decreased significantly with increased impairment level. Across tasks, phases of reaching distally were comparable in terms of trunk displacement, shoulder motions and peak velocity, while reaching proximally showed comparable expressions in trunk motions. Consistent metric relations during reaching distally were found between shoulder flexion/extension, elbow flexion/extension, peak velocity, and between movement time, NVP, and SPARC. Reaching proximally revealed reproducible correlations between forearm pronation/supination and wrist flexion/extension, movement time and NVP. Conclusion Spatiotemporal differences between gestures versus grasp movements and between different impairment levels were confirmed. The consistencies of metric expressions during movement subphases across tasks can be useful for linking kinematic assessment standards and daily living measures in future research and performing task and study comparisons. Trial registration: ClinicalTrials.gov Identifier NCT03135093. Registered 26 April 2017, https://clinicaltrials.gov/ct2/show/NCT03135093.

Evaluation of a four-week Adjunct Compensatory Training for the treatment of climbing-specific overstrain syndromes of the shoulder

Background Although climbing is an increasingly popular sport, there is a lack of scientific evaluation of suitable training methods for climbers, especially with a view to prevention and rehabilitation. A specific rehabilitation program, Adjunct Compensatory Training (ACT), has recently been presented, but it has not been evaluated scientifically to date. Objective To investigate the effects of Adjunct Compensatory Training on climbing-specific overstrain syndromes of the shoulder. Methods Twenty active boulderers and climbers with an average age of 28.9 (± 7.4) years performed a guided shoulder program of six specific exercises from the ACT program over a period of four weeks. They were examined before and after the intervention. Pre- and post-interventional measurements included the Constant-Murley Score, the QuickDASH Score and the measurement of shoulder ROM (range of motion). Results The Constant-Murley Score increased from 82 (± 10.0) to 104.1 (± 8.2) at follow-up (p < 0.001). The VAS value for bouldering and climbing decreased from 5.25 (± 1.4) before to 2.4 (± 1.6) after the intervention (p < 0.001). Shoulder flexion increased from 167.5 (± 14.9) to 173.1 (± 7.7) after the intervention (p < 0.05), abduction from 172.5 (± 14.9) to 179.6 (± 5.9) (n. s.), external rotation from neutral zero position from 77.6 (± 16.8) to 86.3 ± (8.3) (p < 0.05). Feasibility and acceptance of the intervention were good. Ninety-five percent of the participants continued to exercise, and 100 percent recommended the program to others. Conclusion The ACT led to an improvement in pain, activities of daily living, range of motion and strength in boulderers and climbers with overstrain symptoms of the shoulder. It is also classified as a realistically feasible workout. The extent to which this effect will continue, and whether or not the program can prevent injuries, remains to be seen. It can only be presumed that regular exercises prevent shoulder injuries in the climbing population.

Regaining motion among patients with shoulder pathology - are all exercises equal?

Background Little information exists to guide the choice of exercise for regaining shoulder range of motion (ROM). The purpose of this study was to compare the maximal ROM reached, pain and difficulty associated with 4 commonly prescribed exercises. Methods Forty (9 females) patients with various shoulder disorders and a limited flexion ROM performed 4 exercises for regaining shoulder flexion ROM in a randomized order. Exercises included the self-assisted flexion, forward bow, table slide and rope-and-pulley. Participants were videotaped while performing all exercises and the maximal flexion angle reached during each exercise was recorded using Kinovea motion analysis freeware (Kinovea 0.8.15). Pain intensity and the perceived level of difficulty associated with each exercise were also recorded. Results The forward bow and table slide generated significantly greater ROM compared with the self-assisted flexion and rope-and-pulley (P ≤ 0.005). The self-assisted flexion was associated with a greater pain intensity compared with the table slide and rope-and-pulley (P = 0.002) and a greater perceived level of difficulty compared with the table slide (P = 0.006). Conclusions Due to the greater ROM allowed, and similar or even lower level of pain or difficulty, clinicians may wish to initially recommend the forward bow and table slide for regaining shoulder flexion ROM.

Age and Not the Preferred Limb Influences the Kinematic Structure of Pointing Movements

In goal-directed movements, effective open-loop control reduces the need for feedback-based corrective submovements. The purpose of this study was to determine the influence of hand preference and aging on submovements during single- and two-joint pointing movements. A total of 12 young and 12 older right-handed participants performed pointing movements that involved either elbow extension or a combination of elbow extension and horizontal shoulder flexion with their right and left arms to a target. Kinematics were used to separate the movements into their primary and secondary submovements. The older adults exhibited slower movements, used secondary submovements more often, and produced relatively shorter primary submovements. However, there were no interlimb differences for either age group or for the single- and two-joint movements. These findings indicate that open-loop control is similar between arms but compromised in older compared to younger adults.

The Relationship Between Speed and Strength in the Beach Volleyball Serve

The objective of this study was to analyze the relationship between isometric force produced in different joints and its effects on the power kick serve speed in beach volleyball as a predictive aspect to improve sports performance. Seven athletes competing at national and international levels (mean ± standard deviation; age: 21.6 ± 3.20 years; body height: 1.87 ± 0.08 cm; body mass 80.18 ± 7.11 kg) were evaluated using maximum isometric force contractions (i.e., spinal and knee extension, grip by a hand dynamometer (handgrip), internal shoulder rotation, shoulder flexion, elbow flexion and extension, and wrist flexion). Speed of the ball was recorded with a pistol radar and force was measured with a strain gauge. Results showed a relationship between isometric force developed in the internal rotation of the shoulder and speed of the ball (r = 0.76*; p < 0.05). In the remaining isometric exercises, positive low to moderate correlations were found in the spine and knee extension (r = 0.56; p = 0.200) and elbow flexion (r = 0.41; p = 0.375). On the other hand, the remaining isometric exercises obtained weak or non-significant correlations. Force developed in the internal rotation of the shoulder highly correlated with the speed of the power kick, explaining, together with the elbow flexion and the extension of the knee and back, much of the variability of the power kick of beach volleyball athletes.

Sensors for Wheelchair Tennis: Measuring Trunk and Shoulder Biomechanics and Upper Extremity Vibration during Backhand Stroke

This study was the first to compare the differences in trunk/shoulder kinematics and impact vibration of the upper extremity during backhand strokes in wheelchair tennis players and the able-bodied players relative to standing and sitting positions, adopting an electromagnetic system along with wearable tri-axial accelerometers upon target body segments. A total of 15 wheelchair tennis players and 15 able-bodied tennis players enrolled. Compared to players in standing positions, wheelchair players demonstrated significant larger forward trunk rotation in the pre-preparation, acceleration, and deceleration phase. Significant higher trunk angular velocity/acceleration and shoulder flexion/internal rotation angular velocity/acceleration were also found. When able-bodied players changed from standing to sitting positions, significant changes were observed in the degree of forward rotation of the trunk and shoulder external rotation. These indicated that when the functions of the lower limbs and trunk are lacking or cannot be used effectively, “biomechanical solutions” such as considerable reinforcing movements need to be made before the hitting movement. The differences between wheelchair tennis players and able-bodied players in sitting positions could represent the progress made as the wheelchair players evolve from novices to experts. Knowledge about how sport biomechanics change regarding specific disabilities can facilitate safe and inclusive participation in disability sports such as wheelchair tennis.

Reaching higher: External scapula assistance can improve upper limb function in humans with irreversible scapula alata

Background Scapular dyskinesis, i.e., the deviant mobility or function of the scapula, hampers upper limb function in daily life. A typical sign of scapular dyskinesis is a scapula alata—a protrusion of the shoulder blade during arm elevation. While some reversible causes of scapula alata can be treated with therapy, other, irreversible causes require invasive surgical interventions. When surgery is not an option, however, severe limitations arise as standard approaches for assisting the scapula in daily life do not exist. The aim of this study was to quantify functional improvements when external, i.e., non-invasive, scapula assistance is provided. Methods The study was designed as a randomized controlled crossover trial. Eight participants with a scapula alata due to muscular dystrophy performed arm elevations in shoulder flexion and abduction while unassisted (baseline), externally assisted by a trained therapist, and externally assisted by a novel, textile-based scapula orthosis. Results With therapist assistance, average arm elevation increased by 17.3° in flexion (p < 0.001, 95% confidence interval of the mean $$C{I}_{95\%}=\hspace{0.17em}\left[9.8^\circ , 24.9^\circ \right]$$ C I 95 % = 9 . 8 ∘ , 24 . 9 ∘ ), and by 11.2° in abduction (p < 0.01, $$C{I}_{95\%}=\left[4.7^\circ , 17.7^\circ \right]$$ C I 95 % = 4 . 7 ∘ , 17 . 7 ∘ ), constituting the potential of external scapula assistance. With orthosis assistance, average arm elevation increased by 6.2° in flexion ($$C{I}_{95\%}=\left[0.4^\circ ,11.9^\circ \right]$$ C I 95 % = 0 . 4 ∘ , 11 . 9 ∘ ) and by 5.8° in abduction ($$C{I}_{95\%}=\left[3.0^\circ ,8.5^\circ \right]$$ C I 95 % = 3 . 0 ∘ , 8 . 5 ∘ ). Remarkably, in three participants, the orthosis was at least as effective as the therapist. Moreover, orthosis assistance reduced average perceived exertion by 1.25 points (Borg Scale) when elevating a filled bottle during a simulated daily living task. Conclusion These findings indicate a large potential for future advancements in orthotics. Already now, the textile-based scapula orthosis presented here is a feasible tool for leveraging the benefits of external scapula assistance when a therapist is unavailable, as encountered in daily life scenarios. Trial Registration ClincalTrials.gov (ID NCT04154098). Registered: November 6th 2019, https://clinicaltrials.gov/ct2/show/NCT04154098?term=scapula+orthosis&draw=2&rank=1 Graphic abstract

Age-Related Differences in Corticospinal Excitability and Anticipatory Postural Adjustments of the Trunk

Anticipatory postural adjustments (APAs) are a feedforward mechanism for the maintenance of postural stability and are delayed in old adults. We previously showed in young adults that APAs of the trunk induced by a fast shoulder movement were mediated, at least in part, by a cortical mechanism. However, it remains unclear the relationship between delayed APAs and motor cortical excitability in ageing. Using transcranial magnetic stimulation we examined motor evoked potentials (MEPs) of the erector spinae (ES) muscles in healthy young and old adults prior to a fast shoulder flexion task. A recognition reaction time (RRT) paradigm was used where participants responded to a visual stimulus by flexing their shoulders bilaterally as fast as possible. The activity of bilateral anterior deltoid (AD) and ES muscles was recorded using electromyography (EMG). The onset of AD and ES EMG was measured to represent RRT and APAs, respectively. We found increases in amplitudes of ES MEPs at 40 ms than 50 ms prior to the EMG onset of the AD in both groups. The amplitude of ES MEPs at 40 ms prior to the onset of AD EMG correlated with the onset of ES activity counterbalancing the perturbation induced by the shoulder task in the elderly participants only. Our findings suggest that timing of increasing corticospinal excitability prior to a self-paced perturbation becomes more relevant with ageing in modulating postural control of the trunk.

Correlation between Shoulder Range of Motion, Upper Extremity Disability and Quality of Life in Female Breast Cancer Survivors Post Modified Radical Mastectomy: A Pilot Study

Background: Many complications may occur after modified radical mastectomy (MRM) such as restricted shoulder mobility, wound infection, seroma formation, pain and lymph edema. Purpose: To find the correlation between shoulder flexion and abduction range of motion (ROM) with upper extremity disability and quality of life in female post MRM. Methodology: A cross section observation study was conducted in a tertiary care hospital. A total of 20 breast cancer survivors who underwent MRM before 6 months or more were included. Their affected side shoulder flexion and abduction ROM was measured using universal goniometer, upper extremity disability was assessed using Upper Extremity Functional Index (UEFI) and Quality of Life was assessed using WHOQoL-BREF questionnaire. Results: Karl Pearson’s correlation coefficient was used to find the correlation. Strong positive correlation was found between shoulder flexion ROM and UEFI score, physical, psychological and environmental domains, whereas moderate positive correlation was found between shoulder flexion ROM and overall QoL, these were statistically significant (p<0.001). But there was weak positive correlation found between shoulder flexion ROM and social domain of WHOQoL-BREF which was statistically not significant (p>0.001). Further strong positive correlation was found between shoulder abduction ROM and UEFI score, overall Qol, physical and psychological domain and moderate positive correlation was found between shoulder abduction ROM and environmental domain whereas again weak positive correlation found with social domain which was statistically not significant (p>0.001). Conclusion: Decreased shoulder ROM can increase upper extremity disability and affect overall QoL in breast cancer survivors post MRM. Keywords: Breast cancer survivors, Modified Radical Mastectomy, Quality of Life, Shoulder ROM, Upper extremity disability.