Myoelectric prosthesis users and non-disabled individuals wearing a simulated prosthesis exhibit similar compensatory movement strategies.

BACKGROUND: Research studies on upper limb prosthesis function often rely on the use of simulated myoelectric prostheses (attached to and operated by individuals with intact limbs), primarily to increase participant sample size. However, it is not known if these devices elicit the same movement strategies as myoelectric prostheses (operated by individuals with amputation). The objective of this study was to address the question of whether non-disabled individuals using simulated prostheses employ the same compensatory movements (measured by hand and upper body kinematics) as individuals who use actual myoelectric prostheses. METHODS: The upper limb movements of two participant groups were investigated: (1) twelve non-disabled individuals wearing a simulated prosthesis, and (2) three individuals with transradial amputation using their custom-fitted myoelectric devices. Motion capture was used for data collection while participants performed a standardized functional task. Performance metrics, hand movements, and upper body angular kinematics were calculated. For each participant group, these measures were compared to those from a normative baseline dataset. Each deviation from normative movement behaviour, by either participant group, indicated that compensatory movements were used during task performance. RESULTS: Results show that participants using either a simulated or actual myoelectric prosthesis exhibited similar deviations from normative behaviour in phase durations, hand velocities, hand trajectories, number of movement units, grip aperture plateaus, and trunk and shoulder ranges of motion. CONCLUSIONS: This study suggests that the use of a simulated prosthetic device in upper limb research offers a reasonable approximation of compensatory movements employed by a low- to moderately-skilled transradial myoelectric prosthesis user.

Development and reliability of the rating of compensatory movements in upper limb prosthesis wearers during work-related tasks.

STUDY DESIGN: Reliability study. INTRODUCTION: Quantifying compensatory movements during work-related tasks may help to prevent musculoskeletal complaints in individuals with upper limb absence. PURPOSE OF THE STUDY: (1) To develop a qualitative scoring system for rating compensatory shoulder and trunk movements in upper limb prosthesis wearers during the performance of functional capacity evaluation tests adjusted for use by 1-handed individuals (functional capacity evaluation-one handed [FCE-OH]); (2) to examine the interrater and intrarater reliability of the scoring system; and (3) to assess its feasibility. METHODS: Movement patterns of 12 videotaped upper limb prosthesis wearers and 20 controls were analyzed. Compensatory movements were defined for each FCE-OH test, and a scoring system was developed, pilot tested, and adjusted. During reliability testing, 18 raters (12 FCE experts and 6 physiotherapists/gait analysts) scored videotapes of upper limb prosthesis wearers performing 4 FCE-OH tests 2 times (2 weeks apart). Agreement was expressed in % and kappa value. Feasibility (focus area's "acceptability", "demand," and "implementation") was determined by using a questionnaire. RESULTS: After 2 rounds of pilot testing and adjusting, reliability of a third version was tested. The interrater reliability for the first and second rating sessions were к = 0.54 (confidence interval [CI]: 0.52-0.57) and к = 0.64 (CI: 0.61-0.66), respectively. The intrarater reliability was к = 0.77 (CI: 0.72-0.82). The feasibility was good but could be improved by a training program. DISCUSSION: It seems possible to identify compensatory movements in upper limb prosthesis wearers during the performance of FCE-OH tests reliably by observation using the developed observational scoring system. CONCLUSIONS: Interrater reliability was satisfactory in most instances; intrarater reliability was good. Feasibility was established.

Flexible and static wrist units in upper limb prosthesis users: functionality scores, user satisfaction and compensatory movements.

BACKGROUND: The current study examines the relevance of prosthetic wrist movement to facilitate activities of daily living or to prevent overuse complaints. Prosthesis hands with wrist flexion/extension capabilities are commercially available, but research on the users' experiences with flexible wrists is limited. METHODS: In this study, eight transradial amputees using a myoelectric prosthesis tested two prosthesis wrists with flexion/extension capabilities, the Flex-wrist (Otto Bock) and Multi-flex wrist (Motion Control), in their flexible and static conditions. Differences between the wrists were assessed on the levels of functionality, user satisfaction and compensatory movements after two weeks use. RESULTS: No significant differences between flexible and static wrist conditions were found on activity performance tests and standardized questionnaires on satisfaction. Inter-individual variation was remarkably large. Participants' satisfaction tended to be in favour of flexible wrists. All participants but one indicated that they would choose a prosthesis hand with wrist flexion/extension capabilities if allowed a new prosthesis. Shoulder joint angles, reflecting compensatory movements, showed no clear differences between wrist conditions. CONCLUSIONS: Overall, positive effects of flexible wrists are hard to objectify. Users seem to be more satisfied with flexible wrists. A person's needs, work and prosthesis skills should be taken into account when prescribing a prosthesis wrist. TRIAL REGISTRATION: Nederlands Trial Register NTR3984 .

Visuomotor adaptation, internal modelling, and compensatory movements in children with developmental coordination disorder.

BACKGROUND: Developmental coordination disorder (DCD) is one of the most prevalent developmental disorders in school-aged children. The mechanisms and etiology underlying DCD remain somewhat unclear. Altered visuomotor adaptation and internal model deficits are discussed in the literature. AIMS: The study aimed to investigate visuomotor adaptation and internal modelling to determine whether and to what extent visuomotor learning might be impaired in children with DCD compared to typically developing children (TD). Further, possible compensatory movements during visuomotor learning were explored. METHODS AND PROCEDURES: Participants were 12 children with DCD (age 12.4 ± 1.8, four female) and 18 age-matched TD (12.3 ± 1.8, five female). Visuomotor learning was measured with the Motor task manager. Compensatory movements were parameterized by spatial and temporal variables. OUTCOMES AND RESULTS: Despite no differences in visuomotor adaptation or internal modelling, significant main effects for group were found in parameters representing movement accuracy, motor speed, and movement variability between DCD and TD. CONCLUSIONS AND IMPLICATIONS: Children with DCD showed comparable performances in visuomotor adaptation and internal modelling to TD. However, movement variability was increased, whereas movement accuracy and motor speed were reduced, suggesting decreased motor acuity in children with DCD.

Movement Component Analysis of Reaching Strategies in Individuals With Stroke: Preliminary Study.

BACKGROUND: Upper limb motor paresis is a major symptom of stroke, which limits activities of daily living and compromises the quality of life. Kinematic analysis offers an in-depth and objective means to evaluate poststroke upper limb paresis, with anticipation for its effective application in clinical settings. OBJECTIVE: This study aims to compare the movement strategies of patients with hemiparesis due to stroke and healthy individuals in forward reach and hand-to-mouth reach, using a simple methodology designed to quantify the contribution of various movement components to the reaching action. METHODS: A 3D motion analysis was conducted, using a simplified marker set (placed at the mandible, the seventh cervical vertebra, acromion, lateral epicondyle of the humerus, metacarpophalangeal [MP] joint of the index finger, and greater trochanter of the femur). For the forward reach task, we measured the distance the index finger's MP joint traveled from its starting position to the forward target location on the anterior-posterior axis. For the hand-to-mouth reach task, the shortening of the vertical distance between the index finger MP joint and the position of the chin at the start of the measurement was measured. For both measurements, the contributions of relevant upper limb and trunk movements were calculated. RESULTS: A total of 20 healthy individuals and 10 patients with stroke participated in this study. In the forward reach task, the contribution of shoulder or elbow flexion was significantly smaller in participants with stroke than in healthy participants (mean 52.5%, SD 24.5% vs mean 85.2%, SD 4.5%; P<.001), whereas the contribution of trunk flexion was significantly larger in stroke participants than in healthy participants (mean 34.0%, SD 28.5% vs mean 3.0%, SD 2.8%; P<.001). In the hand-to-mouth reach task, the contribution of shoulder or elbow flexion was significantly smaller in participants with stroke than in healthy participants (mean 71.8%, SD 23.7% vs mean 90.7%, SD 11.8%; P=.009), whereas shoulder girdle elevation and shoulder abduction were significantly larger in participants with stroke than in healthy participants (mean 10.5%, SD 5.7% vs mean 6.5%, SD 3.0%; P=.02 and mean 16.5%, SD 18.7% vs mean 3.0%, SD 10.4%; P=.02, respectively). CONCLUSIONS: Compared with healthy participants, participants with stroke achieved a significantly greater distance via trunk flexion in the forward reach task and shoulder abduction and shoulder girdle elevation in the hand-to-mouth reach task, both of these differences are regarded as compensatory movements. Understanding the characteristics of individual motor strategies, such as dependence on compensatory movements, may contribute to tailored goal setting in stroke rehabilitation.

Judokas Show Increased Resilience to Unpredictable Stance Perturbations.

Combat sports are characterized by frequent large-scale stance perturbations that may lead to falls. In the present investigation, we compared compensatory arm and leg movements in response to unpredictable stance perturbations between judokas and other athletes whose sports present reduced balance demand, relative to combat sports. Specifically, we tested judokas (n = 9), and a group of swimmers and runners (n = 11, controls) in sudden support base displacements in the mediolateral direction, generated by a movable electronic platform, in the following modes: (a) rotation, (b) translation, and (c) combined rotation-translation. The platform was displaced to either side, in three peak velocities (cm/second or o/second) of 20 (low), 30 (moderate), or 40 (high), resulting in 18 distinct perturbations. We evaluated postural responses with a scale for analyzing the stability of compensatory arm and leg movements (CALM). Results showed that, in the most challenging perturbations, judokas had higher stability scores (arm, leg, and global) than did the comparison group. Higher scores for judokas reflected their increased rate of motionless arm and leg responses and absence of near-falls, compared to 30% falls in the most challenging perturbations for the swimmers and runners. As a practical application, judo training may help achieve stable compensatory limb movements in a way that parallels the benefits obtained from perturbation-based balance training in laboratory settings.

Knee biomechanical factors associated with patellofemoral pain in recreational runners.

BACKGROUND: Patellofemoral pain (PFP) is a common injury among runners. Knee biomechanical factors associated with PFP, however, remain unclear. The purpose of this study was to determine possible associations between knee biomechanics and symptoms of PFP in recreational runners. METHODS: Fifteen male and 15 female recreational runners with PFP were enrolled as the PFP group, 30 matched runners without PFP were recruited as the control group. The PFP group was tested running with and without knee pain, while the control group had only one running test. Reflective marker coordinates and ground reaction force data were collected in each test. Knee kinematics and kinetics during running were reduced and compared between groups (PFP group without knee pain and control group) and between pain conditions (PFP group with knee pain and without knee pain), as well as between sexes. RESULTS: Female and male participants with PFP had an increased peak knee valgus angle when running without pain compared to matched controls (P = 0.001), and to themselves when running with pain (P = 0.001). Male participants with PFP also had an increased peak knee flexion angle when running without pain compared to matched controls (P = 0.008), however did not decrease their peak knee flexion angle when running with pain (P = 0.245). No significant main effect of group or pain condition on any peak knee joint moment during running was detected (P ≥ 0.175). CONCLUSIONS: Increased peak knee valgus angle during running appears to be a critical biomechanical factor associated with PFP in recreational runners, while decreasing knee valgus angle during running may be an adaptation to reduce symptoms of PFP. Increased peak knee flexion angle during running appears to be another biomechanical factor associated with PFP that is sex specific for male recreational runners.

Usefulness of 2D Video Analysis for Evaluation of Shoulder Range of Motion during Upper Limb Exercise in Patients with Psychiatric Disorders.

Aging and its associated problems related to movement impacts the care of people with psychiatric disorders. This study sought to clarify the usefulness of 2D video analysis for evaluating shoulder range of motion (ROM) during upper limb exercises in patients with psychiatric disorders. Subjects (N=54) were patients with psychiatric disorders categorized as the following:having either a high or low activities of daily living (ADL) score using the Barthel Index;experiencing shoulder ROM limitation, and whether or not compensatory movements were exhibited. Compensatory movement was also considered in patients with Parkinsonism, cerebrovascular disease, and cognitive dysfunction. Shoulder joint ROM was measured using a goniometer and active ROM was captured using ImageJ. No significant difference between passive ROM measured by a goniometer and active ROM measured by ImageJ considering disease groups, ADL level, and shoulder ROM limitation was found. Factoring in compensatory movements, however, significant differences were found between passive and active ROM:existence compensatory movement group, left side (z=-2.30, p=0.02);nonexistence compensatory movement group, right side (z=-2.63, p<0.001). Image-evaluating devices help assess ROM in patients with psychiatric disorders, enhancing the development of physical rehabilitation programs to regain critical ADL, sustaining self-care capabilities. J. Med. Invest. 69 : 70-79, February, 2022.

Automating provision of feedback to stroke patients with and without information on compensatory movements: A pilot study.

Providing effective feedback to patients in a rehabilitation training program is essential. As technologies are being developed to support patient training, they need to be able to provide the users with feedback on their performance. As there are various aspects on which feedback can be given (e.g., task success and presence of compensatory movements), it is important to ensure that users are not overwhelmed by too much information given too frequently by the assistive technology. We created a rule-based set of guidelines for the desired hierarchy, timing, and content of feedback to be used when stroke patients train with an upper-limb exercise platform which we developed. The feedback applies to both success on task completion and to the execution of compensatory movements, and is based on input collected from clinicians in a previous study. We recruited 11 stroke patients 1-72 months from injury onset. Ten participants completed the training; each trained with the rehabilitation platform in two configurations: with motor feedback (MF) and with no motor feedback (control condition) (CT). The two conditions were identical, except for the feedback content provided: in both conditions they received feedback on task success; in the MF condition they also received feedback on making undesired compensatory movements during the task. Participants preferred the configuration that provided feedback on both task success and quality of movement (MF). This pilot experiment demonstrates the feasibility of a system providing both task-success and movement-quality feedback to patients based on a decision tree which we developed.

Pathway-specific cortico-muscular coherence in proximal-to-distal compensation during fine motor control of finger extension after stroke.

Objective.Proximal-to-distal compensation is commonly observed in the upper extremity (UE) after a stroke, mainly due to the impaired fine motor control in hand joints. However, little is known about its related neural reorganization. This study investigated the pathway-specific corticomuscular interaction in proximal-to-distal UE compensation during fine motor control of finger extension post-stroke by directed corticomuscular coherence (dCMC).Approach.We recruited 14 chronic stroke participants and 11 unimpaired controls. Electroencephalogram (EEG) from the sensorimotor area was concurrently recorded with electromyography (EMG) from extensor digitorum (ED), flexor digitorum (FD), triceps brachii (TRI) and biceps brachii (BIC) muscles in both sides of the stroke participants and in the dominant (right) side of the controls during the unilateral isometric finger extension at 20% maximal voluntary contractions. The dCMC was analyzed in descending (EEG → EMG) and ascending pathways (EMG → EEG) via the directed coherence. It was also analyzed in stable (segments with higher EMG stability) and less-stable periods (segments with lower EMG stability) subdivided from the whole movement period to investigate the fine motor control. Finally, the corticomuscular conduction time was estimated by dCMC phase delay.Main results.The affected limb had significantly lower descending dCMC in distal UE (ED and FD) than BIC (P< 0.05). It showed the descending dominance (significantly higher descending dCMC than the ascending,P< 0.05) in proximal UE (BIC and TRI) rather than the distal UE as in the controls. In the less-stable period, the affected limb had significantly lower EMG stability but higher ascending dCMC (P< 0.05) in distal UE than the controls. Furthermore, significantly prolonged descending conduction time (∼38.8 ms) was found in ED in the affected limb than the unaffected (∼26.94 ms) and control limbs (∼25.74 ms) (P< 0.05).Significance.The proximal-to-distal UE compensation in fine motor control post-stroke exhibited altered descending dominance from the distal to proximal UE, increased ascending feedbacks from the distal UE for fine motor control, and prolonged descending conduction time in the agonist muscle.

Analysis of Compensatory Movements Using a Supernumerary Robotic Hand for Upper Limb Assistance.

Recently, extratheses, aka Supernumerary Robotic Limbs (SRLs), are emerging as a new trend in the field of assistive and rehabilitation devices. We proposed the SoftHand X, a system composed of an anthropomorphic soft hand extrathesis, with a gravity support boom and a control interface for the patient. In preliminary tests, the system exhibited a positive outlook toward assisting impaired people during daily life activities and fighting learned-non-use of the impaired arm. However, similar to many robot-aided therapies, the use of the system may induce side effects that can be detrimental and worsen patients' conditions. One of the most common is the onset of alternative grasping strategies and compensatory movements, which clinicians absolutely need to counter in physical therapy. Before embarking in systematic experimentation with the SoftHand X on patients, it is essential that the system is demonstrated not to lead to an increase of compensation habits. This paper provides a detailed description of the compensatory movements performed by healthy subjects using the SoftHand X. Eleven right-handed healthy subjects were involved within an experimental protocol in which kinematic data of the upper body and EMG signals of the arm were acquired. Each subject executed tasks with and without the robotic system, considering this last situation as reference of optimal behavior. A comparison between two different configurations of the robotic hand was performed to understand if this aspect may affect the compensatory movements. Results demonstrated that the use of the apparatus reduces the range of motion of the wrist, elbow and shoulder, while it increases the range of the trunk and head movements. On the other hand, EMG analysis indicated that muscle activation was very similar among all the conditions. Results obtained suggest that the system may be used as assistive device without causing an over-use of the arm joints, and opens the way to clinical trials with patients.

THE EFFECTS OF POSTURAL AND ANATOMICAL ALIGNMENT ON SPEED, POWER, AND ATHLETIC PERFORMANCE IN MALE COLLEGIATE ATHLETES: A RANDOMIZED CONTROLLED TRIAL.

BACKGROUND: Many human beings are strongly influenced by right-sided dominance. This may cause potentially pathologic or dysfunctional asymmetries within the innominates of the pelvis, which in turn influences movement throughout the body including the glenohumeral (GH), vertebral, femoral acetabular (FA), sacroiliac, and costovertebral joints. Techniques based upon the science of Postural Restoration® may help correct these asymmetries and improve multiple physiological and mechanical aspects of sports performance. PURPOSE: To examine difference between non-manual, Postural Restoration® exercises and traditional postural interventions on anatomical alignment, available range of motion and symmetry, and speed and power in active college-aged males. STUDY DESIGN: Randomized control trial, pretest-posttest control group design. METHODS: 25 male collegiate students (age = 21 ± 3 years) who met the ACSM guidelines to be considered physically active were chosen to participate. Participants completed a vertical jump test using a power analyzer (Tendo Sport, Lexington, SC, USA) and the pro agility test. Anatomical alignment was assessed through an adduction drop test, extension drop test, and standard goniometric measurements including femoral acetabular external rotation (ER), internal rotation (IR), flexion, and abduction, and glenohumeral internal rotation. Participants were randomly assigned to either non-manual, Postural Restoration® techniques or traditional posture improvement exercises. Following a four-week intervention period, participants were reassessed using the same aforementioned outcomes completed pre-intervention. RESULTS: Participants who completed the non-manual, Postural Restoration® techniques demonstrated significant improvements in pro-agility scores (-0.03 ± 0.10 seconds; p=0.0005). Neither set of interventions improved vertical jump scores (Treatment: + 35.7 ± 288.02 W, p=0.1000; Control: -10.08 ± 301.04 W, p=0.381). Areas of anatomical alignment that demonstrated significant change included the treatment group for FA IR (p=0.010) and FA abduction (p=0.035) symmetry and the left adduction drop test (p=0.039). CONCLUSION: Non-manual exercise techniques based upon the science of Postural Restoration® may equalize asymmetries present in FA internal rotation and hip abduction. Improvements in symmetry of joint motion may indicate a restoration of neutrality of the pelvis and femoroacetabular joints. By improving anatomical alignment, through establishing a neutral pelvis, athletes may demonstrate improved neuromechanical efficiency, and kinesthetic control of multi-directional motions required for enhanced sports performance markers. LEVEL OF EVIDENCE: 1b.