Non-dominant Limb Research Articles

Retrospective Study of Autologous Arteriovenous Fistula Creation as Vascular Access for Hemodialysis

IntroductionAn autologous arteriovenous fistula (AVF) creation is a common vascular procedure forhemodialysis (HD) patients. This surgical procedure aim is to design a vascular conduct thatwithstands hemodialysis for a durable period. However, the functional outcome of this procedurevaries and depends on patients’ various predictors. .MethodsA retrospective observational study was carried out to evaluate the functional outcome of AVFcreation at the cardiothoracic vascular surgery unit of the surgery department of B.P KoiralaInstitute of Health Sciences from February 2019 to February 2020. The medical file of the patientswas studied, relevant data entered and analyzed in SPSS statistical software.ResultsThere were a total of 112 autologous AVF created during the study period. The mean age ofthe patients was 48.66±15.64 years. There were 75(67%) males and 37(33%) females. The mostcommon limb of fistula creation was left non-dominant upper limb 95(84.8%) and right upper limb17(15.2%). The most common type of AVF was radiocephalic fistula 66(58.9%) and brachiocephalicfistula 46(41.1%). There were 92(82.1%) mature fistula at eight weeks follow-up. These include54(48.2%) radiocephalic fistulas and 38(33.9%) brachiocephalic fistulas. There were 20(17.8%)delayed matured fistulas at 12 weeks (12 radiocephalic and 8 brachiocephalic AVF).ConclusionsThe creation of an autologous AVF for hemodialysis in the upper limb has fewer complications andthe maturation of the AVF depends on the vessel’s diameter. Radio-cephalic and BrachiocephalicAVF usually matures between six to eight weeks duration

Multiparametric Skin Assessment in a Monocentric Cohort of Systemic Sclerosis Patients: Is There a Role for Ultra-High Frequency Ultrasound?

Background: To assess skin involvement in a cohort of patients with systemic sclerosis (SSc) by comparing results obtained from modified Rodnan skin score (mRSS), durometry and ultra-high frequency ultrasound (UHFUS). Methods: SSc patients were enrolled along with healthy controls (HC), assessing disease-specific characteristics. Five regions of interest were investigated in the non-dominant upper limb. Each patient underwent a rheumatological evaluation of the mRSS, dermatological measurement with a durometer, and radiological UHFUS assessment with a 70 MHz probe calculating the mean grayscale value (MGV). Results: Forty-seven SSc patients (87.2% female, mean age 56.4 years) and 15 HC comparable for age and sex were enrolled. Durometry showed a positive correlation with mRSS in most regions of interest (p = 0.025, ρ = 0.34 in mean). When performing UHFUS, SSc patients had a significantly thicker epidermal layer (p < 0.001) and lower epidermal MGV (p = 0.01) than HC in almost all the different regions of interest. Lower values of dermal MGV were found at the distal and intermediate phalanx (p < 0.01). No relationships were found between UHFUS results either with mRSS or durometry. Conclusions: UHFUS is an emergent tool for skin assessment in SSc, showing significant alterations concerning skin thickness and echogenicity when compared with HC. The lack of correlations between UHFUS and both mRSS and durometry suggests that these are not equivalent techniques but may represent complementary methods for a full non-invasive skin evaluation in SSc.

Teaching Video NeuroImages: Susac syndrome's acute onset callosal disconnection

A 59-year-old right-handed hypertensive diabetic and previously alcoholic man presented acute confusional state followed by apathy, dysexecutive syndrome, clumsy left hand, and apraxic gait. A year later, his wife noticed impaired hearing. Neurologic examination revealed marked callosal apraxia (nondominant limb ideomotor apraxia, disconnection variant) and left stereoagnosis due to callosal disconnection (video). Left hand agraphia was present without aphasia. MRI showed punched out holes through corpus callosum, sparing the calloso-septal interface (figure 1). Audiometry revealed left neurosensorial loss. Fluorescein retinography demonstrated hyperfluorescence of arterial vessel wall (figure 2), confirming the hypothesis of Susac syndrome.1

ANTERIOR CRUCIATE LIGAMENT-INJURED FEMALE ADOLESCENTS USE MORE THEIR NON-INJURED LIMB TO PERFORM A COUNTERMOVEMENT JUMP IN RELATION TO THE INJURED LIMB

To investigate if the countermovement jump height differs between ACL injured and uninjured female adolescents and to explore kinematic differences between limbs. Additionally, the association between isometric knee extension strength and jump height was investigated.Thirty-one ACL injured female adolescents (ACLi, 15.3 ± 1.4yrs, 163.9 ± 6.6cm, 63.0 ± 9.3kg) and thirty-eight uninjured (CON, 13.2±1.7yrs, 161.7 ± 8.1cm, 50.6 ± 11.1kg) participated in this study. All participants performed a countermovement jump task, with 3D kinematics collected using a motion analysis system (Vicon, Nexus, Oxford, UK) at 200Hz, and a maximum isometric knee extension task on an isokinetic dynamometer (Biodex Medical Systems, New York, USA) for three trials. The peak torque was extracted from the isometric trials. Independent samples t-test compared the maximum jump height normalised by the dominant leg length between groups, paired samples t-test compared the maximum hip and knee extension and ankle plantar flexion velocities before take-off between limbs in both groups, and a Pearson's correlation test investigated the association between the isometric knee extension strength and jump height.The ACLi jumped 13% lower compared to the CON (p=0.022). In the ACLi, the maximum hip and knee extension and ankle plantar flexion velocities were greater in the non-injured limb, compared to the injured limb; however, no differences between limbs were found in the CON. The isometric knee extension strength of both limbs was positively correlated with jump height (limb 1: r=0.329; p=0.006, and limb 2: r=0.386; p=0.001; whereas limb 1 corresponds to the ACLi injured limb and CON non-dominant limb, and limb 2 to the ACLi non-injured limb and CON dominant limb).ACL injured female adolescents present lower jump height than controls and greater contribution of their non-injured limb, compared to their injured limb, during a countermovement jump task. Also, current results indicate that jump height is positively related to isometric knee extension strength measure.

ROLE OF RING EXTERNAL FIXATOR IN OPEN INTRA-ARTICULAR DISTAL HUMERUS FRACTURE

Standard fixation for intra-articular distal humerus fracture is open reduction and internal fixation (ORIF). However, high energy fractures of the distal humerus are often accompanied with soft tissue injuries and or vascular injuries which limits the use of internal fixation. In our report, we describe a highly complex distal humerus fracture that showed promising healing via a ring external fixator.A 26-year-old man sustained a Gustillo Anderson Grade IIIB intra-articular distal humerus fracture of the non-dominant limb with bone loss at the lateral column. The injury was managed with aggressive wound debridement and cross elbow stabilization via a hinged ring external fixator. Post operative wound managed with foam dressing. Post-operatively, early controlled mobilization of elbow commenced. Fracture union achieved by 9 weeks and frame removed once fracture united. No surgical site infection or non-union observed throughout follow up. At 2 years follow up, flexion - extension of elbow is 20°- 100°, forearm supination 65°, forearm pronation 60° with no significant valgus or varus deformity.The extent of normal anatomic restoration in elbow fracture fixation determines the quality of elbow function with most common complication being elbow stiffness. Ring fixator is a non-invasive external device which provides firm stabilization of fracture while allowing for adequate soft tissue management. It provides continuous axial micro-movements in the frame which promotes callus formation while avoiding translation or angulation between the fragments. In appropriate frame design, they allow for early rehabilitation of joint where normal range of motion can be allowed in controlled manner immediately post-fixation.Functional outcome of elbow fracture from ring external fixation is comparable to ORIF due to better rehabilitation and lower complications. Ring external fixator in our patient achieved acceptable functional outcome and fracture alignment meanwhile the fracture was not complicated with common complications seen in ORIF.In conclusion, ring external fixator is as effective as ORIF in treating complex distal humeral fractures and should be considered for definitive fixation in such fractures.

The effects of equipment carriage on functional movement quality among law enforcement officers

Law enforcement officers (LEOs) use protective equipment to ensure safety. However, equipment carriage has been shown to impair movement quality and may increase the risk of musculoskeletal injury. Therefore, the objective of this study was to investigate the influence of equipment load carriage on functional movement as measured by the Functional Movement Screen (FMS). It was hypothesised that FMS scores would be negatively impacted by equipment carriage. A counterbalanced cross-over study was utilised and a convenience sample of 31 males and one female active-duty LEOs were included. Participants completed the FMS under two conditions: with and without equipment. Significant median decreases in the equipment condition were observed for hurdle step, shoulder mobility, and rotary stability (p < .01), and deep squat and dominant limb active straight leg raise (ASLR) (p < .05). The non-dominant limb ASLR and trunk stability push-up were similar between conditions (p > .05). Load carriage appears to impair functional movement among LEOs. Practitioner summary: Equipment carriage interferes with functional movement and neither of the two load carriage systems tested were superior to the other. When choosing between duty belt verses duty belt and outer carrier vest carriage, LEO preference, body type, and acclimation to a given carriage type should be considered.

Intersession reliability of quadriceps corticospinal excitability: A functional transcranial magnetic stimulation study

Recording transcranial magnetic stimulation-derived measures during a closed kinetic chain task can serve as a functional technique to assess corticomotor function, which may have implications for activities of daily living or lower extremity injury in physically active individuals. Given the novelty of TMS use in this way, our purpose was to first determine the intersession reliability of quadriceps corticospinal excitability during a single-leg squat. We used a descriptive laboratory study to assess 20 physically active females (22.1 ± 2.5 years, 1.7 ± 0.7 m, 66.3 ± 13.6 kg, Tegner Activity Scale: 5.90 ± 1.12) over a 14-day period. Two-way mixed effects Intraclass Correlation Coefficients (3,1) (ICC) for absolute agreement were used to assess intersession reliability. The active motor threshold (AMT) and normalized motor evoked potential (MEP) amplitudes were assessed in the vastus medialis of each limb. The dominant limb AMTs demonstrated moderate-to-good reliability (ICC = 0.771, 95% CI = 0.51–0.90; p < 0.001). The non-dominant limb AMTs (ICC = 0.364, 95% CI = 0.00–0.68, p = 0.047), dominant limb MEPs (ICC = 0.192, 95% CI = 0.00–0.71; p = 0.340), and non-dominant limb MEPs (ICC = 0.272, 95% CI = 0.00–0.71; p = 0.235) demonstrated poor-to-moderate reliability. These findings may provide insight into corticomotor function during activities requiring weight-bearing, single-leg movement. However, variability in agreement suggests further work is warranted to improve the standardization of this technique prior to incorporating in clinical outcomes research.

Influence of the Hawthorne effect on spatiotemporal parameters, kinematics, ground reaction force, and the symmetry of the dominant and nondominant lower limbs during gait

The Hawthorne effect is a change in behavior resulting from awareness of being observed or evaluated. This study aimed to determine whether awareness of being evaluated or presence of an observer influence gait. Twenty-one young women were asked to walk in three conditions. In the first condition (unawareness of evaluation; UE), participants were aware that it was a practice trial, and there was no observer. In the second condition (awareness of evaluation; AE), participants were aware that their gait was being evaluated. The third condition (AE + researcher observation; RO) was similar to the second condition except that an additional researcher observed the participant' gait. The spatiotemporal, kinematic, ground reaction forces, and ratio index (symmetry of both lower limbs) were compared among the three conditions. A higher ratio index indicated a relative increase in the value on left versus right. Gait speed (P = 0.012) and stride length (right and left; P = 0.006 and 0.007, respectively) were significantly increased in the AE + RO than in UE. Range of motion of the right hip and left ankle was significantly greater in AE than in UE (P = 0.039 and 0.012, respectively). The ratio index of ground reaction force during push-off was significantly higher in AE and AE + RO conditions than in UE (P < 0.001 and P = 0.004, respectively). The Hawthorne effect (awareness of being evaluated or presence of an observer) potentially influences gait. Thus, factors that influence gait analysis should be considered when evaluating normal gait.

Effects of walking football on adherence, safety, quality of life and physical fitness in patients with prostate cancer: Findings from the PROSTATA_MOVE randomized controlled trial.

To analyze the feasibility and impact of a walking football (WF) program on quality of life (QoL), cardiorespiratory fitness (CRF), muscle strength, and balance program in men with prostate cancer under androgen deprivation therapy (ADT). Fifty patients with prostate cancer (stages IIb-IVb) under ADT were randomized to a 16-week WF program plus usual care (n=25) or usual care control group (n=25). The WF program consisted of three 90-minute sessions per week. Recruitment, withdrawal, adherence, enjoyment rate, and safety of the intervention were recorded throughout the study. Cardiorespiratory fitness was assessed before and after the interventions, while handgrip strength, lower limb muscle strength, static balance, and QoL were assessed before, during (week 8), and after (week 16) the interventions. Adverse events during sessions were also recorded. The WF group showed high levels of adherence (81.6 ± 15.9%) and enjoyment rate (4.5 ± 0.5 out of 5 points). In the intention-to-treat analysis, the WF group showed an improvement in chair sit-to-stand (p=0.035) compared to the control group. Within-group comparisons showed that handgrip strength in the dominant upper limb (p=0.024), maximal isometric muscle strength in the non-dominant lower limb (p=0.006), and balance in the dominant limb (p=0.009) improved over time in the WF group but not in the usual care group. The results obtained from the per-protocol analysis indicate that CRF improved significantly in the WF group as compared to the control group (p=0.035). Within-group analysis revealed that CRF (p=0.036), muscle strength in dominant (p=0.006) and non-dominant (p=0.001) lower limbs, and balance in the non-dominant lower limb (p=0.023) improved after 16 weeks of WF, but not in the control group. One major traumatic injury (muscle tear) was reported with a complete recovery before the end of the intervention. This study suggests that WF is feasible, safe, and enjoyable in patients with prostate cancer under hormonal therapy. Furthermore, patients who adhere to the WF program can expect cardiorespiratory fitness, muscle strength, and balance improvements. clinicaltrials.gov, identifier NCT04062162.

The association between muscle mass quantity and its quality in physically active older women

In this study, the authors aim to determine whether lower limb strength is related to lower limb lean mass and whether this relationship is affected by lower limb functionality in physically active older women. Twenty-six women underwent measures of knee muscles strength and lean mass of lower limbs. Bilateral strength of the knee flexors and extensors was measured by an isokinetic dynamometer. The concentric peak torque was measured at an angular velocity of 60°/s. Lean mass of the lower limbs was measured by bio-impedance analysis. Pearson’s correlation analysis revealed significant association between the strength of the knee flexors and lean mass on non-dominant limb only (r = .427, p = .03). Researchers revealed that strategies aiming to prevent lean mass and muscle strength losses should be specifically targeted to individual muscles or muscle groups, even in physically active older women. To improve overall mobility, the strengthening of larger muscle such as hamstring is crucial.

Lumbopelvic-Hip Rhythm in People with Lumbar Flexion-with-Rotation Syndrome during Hip Internal Rotation.

According to previous research, hip internal rotation (HIR) aggravates low back pain (LBP) symptoms, especially in patients with lumbar flexion with rotation (F + R) syndrome. Therefore, the present study aimed to examine the lumbopelvic-hip rhythm during the HIR test in patients with this syndrome. In this cross-sectional study, 20 men without LBP and 20 matched men with LBP, subcategorized in the F+R subgroup, participated. The participants performed the HIR test. Kinematics data were recorded using a motion analysis system. After processing the kinematics, a comparison was made in the hip and pelvic kinematics between the groups. A statistical analysis based on an independent t test revealed a significant increased (P < 0.05) pelvic rotation during the tests with the dominant ( P = 0.007) and nondominant limbs (P = 0.025) in those with LBP. The analysis also showed that during the test with the dominant lower limb, the pelvis and hip moved with a more synchronized pattern in patients with LBP (P = 0.001). In the patients with lumbar F + R syndrome, there was a tendency for early pelvic rotation during the dominant HIR test. Moreover, LBP people also exhibited a greater pelvic rotation range of motion in the first half and whole pathways of the test. These impairments could be a risk factor for the development of LBP symptoms in these patients.

Test−Retest Reliability of Isokinetic Ankle, Knee and Hip Strength in Physically Active Adults Using Biodex System 4 Pro

The isokinetic dynamometry is considered a gold standard in muscle strength testing. The reliability of lower limb isokinetic strength measurements has not been thoroughly evaluated. To examine the test-retest reliability of isokinetic ankle plantar and dorsiflexion, ankle inversion and eversion, knee extension and flexion and hip abduction and adduction strength in physically active adults using Biodex System 4 Pro. Peak torques (PTs) and average peak torques (APTs) of the dominant and nondominant lower limbs were tested twice in 19 physically active adults 7 to 14 days apart. The intraclass correlation coefficients (ICC) values varied from excellent to moderate and coefficient of variation of typical error (CVTE) values were 6.6-19.5%. Change in the mean expressed as a percent varied from -3.1% to 9.6%. There was no difference in the reliability between PT and APT values. Dominant lower limb was more reliable in every case if there was difference between limbs. Test-retest reliability of isokinetic ankle, knee and hip strength in physically active adults using Biodex System 4 is mostly good or excellent. However, the observed range of the random variation has to be noted when using it in scientific follow-up studies or evaluation of patient progress in clinical settings.

Diagnostics Using the Change-of-Direction and Acceleration Test (CODAT) of the Biomechanical Patterns Associated with Knee Injury in Female Futsal Players: A Cross-Sectional Analytical Study

The primary aim of this study was to identify kinematic differences at initial contact between female futsal players with and without previous knee injury, using a functional motor pattern test. The secondary aim was to determine kinematic differences between the dominant and non-dominant limb in the whole group, using the same test. A cross-sectional study was performed in 16 female futsal players allocated into two groups: eight females with a previous knee injury, i.e., affected by the valgus collapse mechanism without surgical intervention, and eight with no previous injury. The evaluation protocol included the change-of-direction and acceleration test (CODAT). One registration was made for each lower limb, i.e., the dominant (the preferred kicking limb) and non-dominant limb. A 3D motion capture system (Qualisys AB, Göteborg, Sweden) was used to analyze the kinematics. The Cohen's d effect sizes between the groups demonstrated a strong effect size towards more physiological positions in the non-injured group in the following kinematics in the dominant limb: hip adduction (Cohen's d = 0.82), hip internal rotation (Cohen's d = 0.88), and ipsilateral pelvis rotation (Cohen's d = 1.06). The t-test for the dominant and non-dominant limb in the whole group showed the following differences in knee valgus: dominant limb (9.02 ± 7.31 degrees) and non-dominant limb (1.27 ± 9.05 degrees) (p = 0.049). Conclusions: The players with no previous history of knee injury had a more physiological position for avoiding the valgus collapse mechanism in the hip adduction and internal rotation, and in the pelvis rotation in the dominant limb. All the players showed more knee valgus in the dominant limb, which is the limb at greater risk of injury.

Computerized and functional reaction time in varsity-level female collegiate athletes with and without a concussion history.

To 1) determine the association between computerized and functional reaction time, and 2) compare functional reaction times between female athletes with and without a concussion history. Cross-sectional study. Twenty female college athletes with concussion history (age = 19.1 ± 1.5 years, height = 166.9 ± 6.7 cm, mass = 62.8 ± 6.9 kg, median total concussion = 1.0 [interquartile range = 1.0, 2.0]), and 28 female college athletes without concussion history (age = 19.1 ± 1.0 years, height = 172.7 ± 8.3 cm, mass = 65.4 ± 8.4 kg). Functional reaction time was assessed during jump landing and dominant and non-dominant limb cutting. Computerized assessments included simple, complex, Stroop, and composite reaction times. Partial correlations investigated the associations between functional and computerized reaction time assessments while covarying for time between computerized and functional reaction time assessments. Analysis of covariance compared functional and computerized reaction time, covarying for time since concussion. There were no significant correlations between functional and computerized reaction time assessments (p-range = 0.318 to 0.999, partial correlation range = -0.149 to 0.072). Reaction time did not differ between groups during any functional (p-range = 0.057 to 0.920) or computerized (p-range = 0.605 to 0.860) reaction time assessments. Post-concussion reaction time is commonly assessed via computerized measures, but our data suggest computerized reaction time assessments are not characterizing reaction time during sport-like movements in varsity-level female athletes. Future research should investigate confounding factors of functional reaction time.

Effects of far-infrared radiation lamp therapy on recovery from muscle damage induced by eccentric exercise

ABSTRACT The present study investigated the effects of a far-infrared radiation (FIR) lamp therapy on changes in muscle damage and proprioception markers after maximal eccentric exercise of the elbow flexors (EF: Study 1) and the knee flexors (KF: Study 2) in comparison to a sham treatment condition. In each study, 24 healthy sedentary women were assigned to a FIR or a sham treatment group (n = 12/group). They performed 72 maximal EF eccentric contractions (Study 1) or 100 maximal KF eccentric contractions (Study 2) with their non-dominant limbs. They received a 30-min FIR (wavelength: 8–14 µm) or sham treatment at 1, 25, 49, 73 and 97 h post-exercise to the exercised muscles. Maximum voluntary isometric contraction (MVC) torque, muscle soreness, plasma creatine kinase activity, and proprioception assessed by position sense, joint reaction angle, and force match were measured before, and 0.5, 24, 48, 72, 96 and 120 h post-exercise. The outcome measures showed significant changes (P < 0.05) at 0.5-hour post-exercise (before treatment) similarly (P > 0.05) between the conditions in both studies. However, changes in all measures at 24–120 h post-exercise were smaller (P < 0.05) for the FIR than sham condition in both studies. For example, MVC torque returned to the baseline by 72 h post-exercise for the FIR condition in both studies, but was still 19 ± 6% (Study 1) or 17 ± 12% (Study 2) lower than the baseline at 120 h post-exercise for the sham condition. These results suggested that the FIR lamp therapy was effective for accelerating recovery from muscle damage.

Balance improvements in healthy subjects are independent to postural strategies involved in the training

BackgroundAdequate postural strategies have a pivotal role in ensuring balance during the performance of daily or sport activities. These strategies are responsible for the management of center of mass kinematics and depend on the magnitude of perturbations and posture assumed by a subject. Research questionAre there differences in postural performance after a standardized balance training performed in sitting versus standing posture in healthy subjects? Does a standardized unilateral balance training with the dominant or non-dominant limb improve balance on trained and untrained limbs in healthy subjects? MethodsSeventy-five healthy subjects reporting a right-leg dominance were randomized into a Sitting, Standing, Dominant, Non-dominant or Control groups. In the Experiment 1, Sitting group performed a 3-week balance training in seated posture, whereas Standing group performed the same training in bipedal stance. In the Experiment 2, Dominant and Non-dominant groups underwent a 3-week standardized unilateral balance training on the dominant and non-dominant limbs, respectively. Control group underwent no intervention and was included in both experiments. Dynamic (Lower Quarter Y-Balance Test with the dominant and non-dominant limbs and trunk and lower limb 3D kinematics) and static (center of pressure kinematics in bipedal and bilateral single-limb stance) balance were assessed before and after the training, and at 4 weeks follow-up. ResultsA standardized balance training in sitting or standing posture improved balance without between-group differences, while a unilateral balance training with the dominant or non-dominant limb improved postural stability on the trained and untrained limbs. Trunk and lower limb joints range of motion increased independently to their involvement in the training. SignificanceThese results may allow clinicians to plan effective balance interventions even when a training in standing posture is not possible or in subjects with restricted limb weight-bearing.

Repeatability and Temporal Consistency of Lower Limb Biomechanical Variables Expressing Interlimb Coordination during the Double-Support Phase in People with and without Stroke Sequelae

Reliable biomechanical methods to assess interlimb coordination during the double-support phase in post-stroke subjects are needed for assessing movement dysfunction and related variability. The data obtained could provide a significant contribution for designing rehabilitation programs and for their monitorisation. The present study aimed to determine the minimum number of gait cycles needed to obtain adequate values of repeatability and temporal consistency of lower limb kinematic, kinetic, and electromyographic parameters during the double support of walking in people with and without stroke sequelae. Eleven post-stroke and thirteen healthy participants performed 20 gait trials at self-selected speed in two separate moments with an interval between 72 h and 7 days. The joint position, the external mechanical work on the centre of mass, and the surface electromyographic activity of the tibialis anterior, soleus, gastrocnemius medialis, rectus femoris, vastus medialis, biceps femoris, and gluteus maximus muscles were extracted for analysis. Both the contralesional and ipsilesional and dominant and non-dominant limbs of participants with and without stroke sequelae, respectively, were evaluated either in trailing or leading positions. The intraclass correlation coefficient was used for assessing intra-session and inter-session consistency analysis. For most of the kinematic and the kinetic variables studied in each session, two to three trials were required for both groups, limbs, and positions. The electromyographic variables presented higher variability, requiring, therefore, a number of trials ranging from 2 to >10. Globally, the number of trials required inter-session ranged from 1 to >10 for kinematic, from 1 to 9 for kinetic, and 1 to >10 for electromyographic variables. Thus, for the double support analysis, three gait trials were required in order to assess the kinematic and kinetic variables in cross-sectional studies, while for longitudinal studies, a higher number of trials (>10) were required for kinematic, kinetic, and electromyographic variables.

Limb Dominance Effects on Seated Single-Arm Shot-Put Limb Symmetry Indices Following Shoulder Rehabilitation

Typically, most clinical return to activity guidelines recommend that an injured shoulder achieve a 90% to 100% functional performance test limb symmetry index (LSI); however, as previous research demonstrated a 103% to 111% dominant limb bias in seated single-arm shot-put test (SSASPT) performance, the typical criteria might not be appropriate for interpreting SSASPT LSI. Thus, the current objective was to evaluate SSASP LSI differences between dominant and nondominant involved shoulders and to determine how many patients met the suggested 90% to 100% LSI criteria, as well as the 103% for dominant (89% for nondominant) normative SSASPT threshold reported in the literature, at the time of discharge. Cross-sectional. Patients with shoulder injury or surgery (n = 78) completed the SSASPT at the time of discharge from rehabilitation and were grouped according to whether the involved shoulder was the dominant (n = 42) or nondominant (n = 32) limb. LSI (involved/uninvolved × 100) was computed from the average of 3 SSASPT trial distances completed with each limb. The LSI for the nondominant involved group (88.9% [12.4%]) was significantly less (confidence intervalDiff, -12.1% to -22.1%) than the dominant involved group (106.0% [9.3%]). While 95.2% of patients in the dominant involved group exhibited LSI > 90%, only 43.8% of patients in the nondominant involved group attained LSI > 90%. Across the entire cohort, the odds of a nondominant involved LSI being below the respective SSASPT normative range were 2.04 (95% confidence interval, 0.80-5.21) times higher than the odds of a dominant involved LSI being below the normative range. Patients with dominant limb involvement exhibited higher LSI than patients with nondominant limb involvement at discharge from rehabilitation. Particularly when the nondominant shoulder is involved, these results suggest that patients with shoulder injury and surgery may require longer rehabilitation to attain higher levels of upper-extremity function.

Analysis of motor characteristics ofreaching movements in children with cerebral palsy

Studies confirm that children with cerebral palsy (CwCP) have difficulty with simple, everyday movements like reaching for objects. Accurate reaching requires that shoulder and elbow joints are coordinated to move the hand along a smooth path to the desired target location. Here we examined multijoint coordination by comparing reaching performance in the affected and unaffected limbs of CwCP (nine children, six girls and three boys, aged 8–10 years) to reaching performance in the non-dominant and dominant limbs of typically-developing age- and gender-matched control (CTR) children. The hypothesis was that CwCP would show the effects of coordination deficits in both their affected and unaffected limbs. All children performed two sessions (one session with each arm) of speeded reaching movements to three targets arranged to manipulate the required pattern of shoulder and elbow coordination. The movements were tracked with a motion tracker allowing us to assess the following measures: movement distance, duration, and speed, hand-path deviation from linearity, final position accuracy and precision, and measures of shoulder and elbow excursion. We found that CwCP made reaches that covered a greater distance and took more time, that their shoulder and elbow rotations were larger, and that their movements showed greater deviation from linearity than the movements performed by CTR children. Children with CP were also more variable than CTR children on every measure except movement duration. The pattern of shoulder and elbow rotation observed in the CwCP group represents a coordination pattern that is significantly different from the pattern used by CTR children and may represent a greater reliance by CwCP on proximal muscular control systems. The discussion section considers the role that the cortical-spinal system may play in multijoint coordination.

Effect of sleep deprivation on postural control and dynamic stability in healthy young adults

BackgroundPostural control results from non-linear interactions of multiple neuromusculoskeletal elements and contextual factors. The use of non-linear analyses that consider the temporal evolution of postural adjustments, such as sample entropy, could inform about the changes in postural control due to contextual disturbances such as sleep deprivation. Research questionWhat are the effects of sleep deprivation on static postural control and dynamic stability in healthy young adults? MethodsA quasi-experimental study was performed with 17 healthy young males submitted to 24 h of monitored sleep deprivation. The postural control was measured using sample entropy, area, and total average velocity of the center of pressure on a force platform. The dynamic stability was measured using the Modified Star Excursion Balance Test (SEBTm) composite score for each lower limb. Repeated-measures analysis of variance (baseline × 12 h × 15 h × 18 h × 21 h × 24 h of sleep deprivation) verified the effect of sleep deprivation in the postural control variables. Paired t-test compared the composite score of the SEBTm between baseline and 24 h sleep deprivation. ResultsSample entropy decreased after 18 h of sleep deprivation (p = 0.032) and 24 h of sleep deprivation (p = 0.001). Despite the significant main effect for the area (p = 0.012) and speed (p = 0.007) of the center of pressure, no pairwise differences were identified in the post hoc analysis. The non-dominant lower limb SEBTm composite score was reduced after 24 h of sleep deprivation (p = 0.033), and no difference was observed in the dominant limb. SignificanceSleep deprivation reduced the adaptability in static postural control and dynamic stability of the non-dominant lower limb of healthy young male adults. Sample entropy seemed more sensitive to capture the effects of sleep deprivation than the classical postural control variables.