Scapular dyskinesis and overhead athletes: A systematic review of electromyography studies.

OBJECTIVE: Understanding how the main scapular muscles behave in overhead athletes with scapular dyskinesis (SD). DESIGN: Systematic Review. SETTING: Electronic searches were performed in Pubmed (MedLine), Embase, CINAHL, and SPORTDiscus databases. PARTICIPANTS: Overhead athletes with SD. MAIN OUTCOME MEASURES: Electromyographic activity of the upper (UT), middle (MT), and lower (LT) trapezius, and serratus anterior (SA). RESULTS: Eight studies were included in this review. The UT activity showed a tended to increase its activity mainly during tasks over 90° compared to 45°. SA activity had similar behavior, mainly during isometric tasks. The MT also increased its activity mainly in tasks with overhead angulations when compared to lower angulations. The LT activation tended to decrease its EMG activity at angulations below 60° in overhead athletes with SD. CONCLUSIONS: The EMG behaviour of UT and SA for non-athletes appears to differ from what has already been described in the literature. The MT seems to be the most neglected muscle for scapular stabilization in overhead athletes with SD. The decrease in LT activity suggests that this may have implications for the performance of these athletes.

Long-term effects of running exercises on natural grass, artificial turf, and synthetic surfaces on ground reaction force components in individuals with overpronated feet: A randomized controlled trial.

BACKGROUND: Overpronated feet are associated with alteration of lower limb mechanics. Also, quantifying ground reaction force-related changes due to exercise on different surfaces is important for understanding the potential risk of injuries. RESEARCH QUESTION: What are the long-term effects of running exercises on natural grass, artificial turf, and synthetic surfaces on ground reaction force components in individuals with overpronated feet? METHODS: Of 82 contacted individuals with overpronated feet aged 18-30, 22 were excluded because they did not meet inclusion criteria (20), and two declined to participate. Sixty individuals were included in randomization, the control (n = 15), hard court or synthetic surface (n = 15), natural grass (n = 15), and artificial turf (n = 15) groups. There was a sample loss of 8 individuals because of personal problems (2 in each group). The intervention groups performed running exercises on natural grass, artificial turf, and synthetic surfaces over eight weeks, three sessions per week. No training or test-related injuries were reported throughout the study. A force plate was embedded midway through the 18-running concrete path to collect ground reaction force data while running on stable ground before and after interventions. RESULTS: Findings demonstrated significant group-by-time interactions for vertical loading rate (p = 0.016, ETA=0.297). Post-hoc analyses showed increased loading rate amplitude in two natural grass and artificial turf groups (but not in the control and synthetic surface groups) post-intervention. SIGNIFICANCE: Running training on natural grass and artificial turf surfaces may place individuals with overpronated feet at a higher risk of injury while running on a stable surface.

The interaction effect of different footwear types and static navicular drop or dynamic ankle pronation on the joint stiffness of the lower limb during running.

BACKGROUND: Although the effects of footwear type on joint stiffness have previously been investigated, researchers did not consider foot flexibility. Thus, the present investigation aimed to determine the interaction effects of footwear type, static navicular drop and dynamic ankle pronation on dynamic joint stiffness in running. RESEARCH QUESTION: Does the footwear types in interaction with the foot posture affect the stiffness of the joints of the lower limb? METHODS: Forty-seven male individuals participated in this study. Firstly, they were divided into the high navicular, low navicular, and normal navicular drop. Secondly, they were divided into the high dynamic ankle pronation, low dynamic ankle pronation, and normal dynamic ankle pronation groups. Participants performed three running trials at 3 ± 0.2 m/s at minimalist footwear, conventional footwear, and barefoot conditions. We collected the ground reaction forces and three-dimensional kinematic data and calculated joint stiffness over the stance phase. RESULTS: There was no significant main effect of navicular drop or dynamic ankle pronation on dynamic joint stiffness for the ankle, knee, and hip (p > 0.05). However, footwear type significantly affected dynamic joint stiffness. The pairwise comparison revealed that the ankle and hip dynamic joint stiffness magnitudes in the conventional footwear condition were greater than in the barefoot and minimalist footwear conditions (p 0.001). In contrast, the knee dynamic joint stiffness magnitude in the conventional footwear condition was lesser than in barefoot and minimalist footwear conditions (p 0.001). SIGNIFICANCE: The navicular drop or dynamic ankle pronation did not influence lower limb joint stiffness, and there was no significant interaction between navicular drop or dynamic ankle pronation and footwear on lower limb dynamic joint stiffness. However, conventional footwear increased the ankle and hip dynamic joint stiffness while reducing knee dynamic joint stiffness, leading to changes in transfer energy, which could have implications for relative injury risk.

Role of gluteus maximus and medius activation in the lower limb biomechanical control during functional single-leg Tasks: A systematic review.

OBJECTIVES: Single-leg (SL) tasks are included as assessment and intervention strategies in several dysfunctions due to the inherent motor control requirement. The recruitment of gluteus maximus (GMAX) and medius (GMED) muscles is essential for proper biomechanical control of the knee and hip joints. The study aims to identify the role of gluteal activation in the biomechanical control of the lower limb during SL tasks. METHODS: This is a systematic review with searches performed in Pubmed, CINAHL, MEDLINE, Web of Science, and Sportdiscus databases. Cross-sectional studies carried out with asymptomatic individuals were selected, containing hip and knee kinematic and kinetic outcomes assessed through 3D or 2D movement analysis and EMG activity of GMED and GMAX muscles. Two independent reviewers performed the procedures to select the studies, determine the methodological quality and extract the data. RESULTS: The initial search resulted in 391 studies, and after the assessment procedures, 11 studies were included. Lower GMAX activation was associated with greater hip internal rotation (HIR) excursion and greater HIR moment, and lower GMED activation was associated with greater hip adduction (HAD)/knee abduction (KAB) excursions and greater KAB moment during single-leg squat (SLS). CONCLUSIONS: The SL tasks showed a relevant association between the gluteal EMG and other biomechanical outcomes, mainly the SLS task. Interpretation must be cautious, as most studies present high and moderate methodological quality, especially on kinetic data.

Could emotional and sensitization status affect postural sway in adults with knee osteoarthritis?

BACKGROUND AND PURPOSE: The manipulation of sensory conditions and attentional demand affect the postural sway in older adults with knee osteoarthritis (KOA). However, it is not known if emotional and sensitization status affects postural sway in this population. This study aimed to test if older adults with mild and moderate knee osteoarthritis with symptoms of depression and high sensitization would change the profile of postural sway. METHODS: Design: A cross-sectional study was undertaken. PARTICIPANTS: The center of pressure parameters of 30 older adults with mild and moderate knee osteoarthritis and 15 healthy controls were evaluated under different conditions manipulating the visual and attentional demand. We used the pressure pain threshold to measure the sensitization status. Furthermore, we applied the Beck Depression Inventory index to assess emotional status. RESULTS: Manipulating the visual demand affected the center of pressure parameters for both groups, without differences between them. Compared to the healthy control group, the knee osteoarthritis group presented with worse scores on the Beck Depression Inventory, lower pressure pain threshold scores, and the correlations between the symptoms of depression and sensitization status ranged from weak to moderate. Finally, in the knee osteoarthritis group, we observed few and weak significant associations between the center of pressure parameters and the Beck Depression Inventory and the pressure pain threshold scores. DISCUSSION: Emotional and sensitization status seem not to be more associated with the center of pressure of older adults with mild to moderate KOA than healthy adults. Thus, it suggests that this population can safely maintain postural sway, irrespective of depression symptoms and high sensitization.

Long-term training on sand changes lower limb muscle activities during running in runners with over-pronated feet.

BACKGROUND: Running on sand could be a promising exercise intervention for the treatment of over-pronated feet. However, there is a lack of knowledge about the effects of running on sand on muscle activities. Therefore, this study aims to evaluate the long-term effects of running on sand on the activities of selected lower limb muscles in individuals with OPF compared with healthy controls. METHODS: Sixty recreational adult male runners with over-pronated feet (foot posture index > 10) were divided into two equal groups (intervention and control). Participants ran barefoot at a pre-defined speed (⁓3.3 m/s) over level stable ground both before and after long-term training on the sand. Muscle activities were recorded using a surface bipolar electromyography system. RESULTS: For the intervention group, we found a reduced foot posture index (p < 0.001; d = 2.00) and significant group-by-time interactions for gluteus medius activity during the mid-stance phase (p < 0.028; d = 0.59). Significantly higher gluteus medius activity (p = 0.028, d = 0.569) was found during the post-test. We also observed significant group-by-time interactions for medial gastrocnemius activity during the push-off phase (p < 0.041; d = 0.54). Significantly larger medial gastrocnemius activity (p = 0.041; d = 0.636) was found during the post-test compared to the pre-test. CONCLUSIONS: Long-term running on sand resulted in reduced pronation, increased medial gastrocnemius activity, and improved frontal plane pelvic stability due to higher gluteus medius activity. TRIAL REGISTRATION: IRCT20191211045704N1. Registered 25 February 2020. Retrospectively registered.

Analysis of ground reaction forces and muscle activity in individuals with anterior cruciate ligament reconstruction during different running strike patterns.

BACKGROUND: Anterior cruciate ligament reconstruction provides successful clinical outcomes. However, reconstruction cannot restore normative lower limb mechanics during running. While numerous studies have investigated running characteristics in individuals with anterior cruciate ligament reconstruction, no study has been compared foot strike patterns among them. RESEARCH QUESTION: If ground reaction forces and lower extremity muscle activities in individuals with anterior cruciate ligament reconstruction and healthy control ones differ during three running strike patterns? METHODS: In this cross-sectional study, fourteen healthy adult males and fourteen adult males with anterior cruciate ligament reconstruction were recruited to participate. Surface electromyography of selected lower limb muscles and ground reaction forces were measured during three-strike patterns: rearfoot strike pattern, midfoot strike pattern, and forefoot strike pattern during barefoot running (∼ 3.3 m/s). RESULTS: The results revealed that the strike patterns influenced the peak lateral ground reaction force (P < 0.001) and peak vertical impact ground reaction force (P = 0.002) during the stance phase of running for both groups. The strike pattern also influenced the tibialis anterior (P < 0.001) and vastus lateralis (P = 0.035) activities during the early stance phase for both groups. However, the vastus medialis (P = 0.030) presented reduced activity, and the biceps femoris (P = 0.039) presented increased activity in the anterior cruciate ligament reconstruction group. Tibialis anterior (P = 0.021), gastrocnemius medialis (P < 0.001) and vastus medialis (P < 0.001) presented lesser activity irrespective of strike patterns in the anterior cruciate ligament reconstruction group. SIGNIFICANCE: Running with a forefoot strike pattern may be associated with lesser rearfoot eversion due to lower peak lateral ground reaction forces than running with a rearfoot strike pattern or midfoot strike pattern. Moreover, the altered muscle activities could contribute to the elevated risk of future joint injury in the anterior cruciate ligament reconstruction population.

Discrimination between healthy and patients with Parkinson's disease from hand resting activity using inertial measurement unit.

BACKGROUND: Parkinson's disease (PD) is a neurological disease that affects the motor system. The associated motor symptoms are muscle rigidity or stiffness, bradykinesia, tremors, and gait disturbances. The correct diagnosis, especially in the initial stages, is fundamental to the life quality of the individual with PD. However, the methods used for diagnosis of PD are still based on subjective criteria. As a result, the objective of this study is the proposal of a method for the discrimination of individuals with PD (in the initial stages of the disease) from healthy groups, based on the inertial sensor recordings. METHODS: A total of 27 participants were selected, 15 individuals previously diagnosed with PD and 12 healthy individuals. The data collection was performed using inertial sensors (positioned on the back of the hand and on the back of the forearm). Different numbers of features were used to compare the values of sensitivity, specificity, precision, and accuracy of the classifiers. For group classification, 4 classifiers were used and compared, those being [Random Forest (RF), Support Vector Machine (SVM), K-Nearest Neighbor (KNN), and Naive Bayes (NB)]. RESULTS: When all individuals with PD were analyzed, the best performance for sensitivity and accuracy (0.875 and 0.800, respectively) was found in the SVM classifier, fed with 20% and 10% of the features, respectively, while the best performance for specificity and precision (0.933 and 0.917, respectively) was associated with the RF classifier fed with 20% of all the features. When only individuals with PD and score 1 on the Hoehn and Yahr scale (HY) were analyzed, the best performances for sensitivity, precision and accuracy (0.933, 0.778 and 0.848, respectively) were from the SVM classifier, fed with 40% of all features, and the best result for precision (0.800) was connected to the NB classifier, fed with 20% of all features. CONCLUSION: Through an analysis of all individuals in this study with PD, the best classifier for the detection of PD (sensitivity) was the SVM fed with 20% of the features and the best classifier for ruling out PD (specificity) was the RF classifier fed with 20% of the features. When analyzing individuals with PD and score HY = 1, the SVM classifier was superior across the sensitivity, precision, and accuracy, and the NB classifier was superior in the specificity. The obtained result indicates that objective methods can be applied to help in the evaluation of PD.

Hyperalgesia affects muscle activity and knee range of motion during a single-limb mini squat in individuals with knee osteoarthritis: a cross-sectional study.

BACKGROUND: The effect of hyperalgesia on functionality remains uncertain for individuals with knee osteoarthritis (KOA). This study aimed examine the clinical measures and hyperalgesia's effect on muscle activity, knee range of motion (ROM) and postural control during the single-leg mini squat (SLMS) in individuals with KOA, determining the correlation between variables. METHODS: In this cross-sectional study, 60 individuals, 30 healthy (HG, 57.4 ± 6.86 years), and 30 with mild to moderate KOA (KOAG, 59.4 ± 5.46 years) were evaluated by the visual analog scale (VAS), Western Ontario and McMaster Universities Index (WOMAC), and the pressure pain threshold (PPT) in subcutaneous, myotomal, and sclerotomal structures. Muscle activity, knee ROM and postural control were assessed during a SLMS. The analyses were performed in the two phases of the SLMS. Phase 1 - during descending movement (eccentric contraction), Phase 2 - during ascending movement (concentric contraction). Analysis of covariance was applied for each variable separately, using weight as a co-variable. We used Spearman's test for determining the correlation. RESULTS: There was no difference between groups for age, height, and postural control (p > 0.059), but KOAG presented the highest values for VAS and WOMAC (p = 0.000). In addition, EMG activity was higher in KOAG for gastrocnemius medialis and tibialis anterior muscles during phase 1 (p < 0.027), and for gastrocnemius medialis and gluteus medius muscles during phase 2 (p < 0.007), and reduced values for PPT and knee ROM (p = 0.000). Also, the correlations between PPT with muscle activity and postural control were moderate (rho< 0.482), while strong relationships were observed between some PPT points with VAS and WOMAC (rho> 0.507). CONCLUSION: Hyperalgesia affects the functionality during a single-limb mini squat. There is an important correlation between hyperalgesia and muscle activity, postural control, and clinical measures in individuals with KOA.

Biomechanical analysis during single-leg squat in individuals with knee osteoarthritis.

Backgroud: The single-leg squat (SLS) is a functional task to evaluate the abnormal movement patterns and potential neuromuscular deficits in the lower limbs. Still, it is unknown if SLS could provide information to older adults with knee osteoarthritis (KOA). The study's objective was to analyze the EMG pattern, kinematics, and postural control in individuals with and without KOA during SLS. METHODS: Participated in this study, 60 volunteers of both sexes, 30 had KOA (allocated into the KOA group - KOAG), and 30 were healthy (allocated into the Healthy Group - HG) performing the single-leg squat. Surface electromyography (EMG) was assessed for the gastrocnemius medialis (GM), biceps femoris (BF), gluteus medius (GLM), rectus femoris (RF), vastus medialis (VM), vastus lateralis (VL), and tibialis anterior (TA) in two phases (downward - P1 and upward - P2). The kinematic data was evaluated using an electrogoniometer. The center of pressure (CoP) was obtained using data collected from a force plate. RESULTS: EMG activity was increased for GM and TA muscles during the P1 of the movement and the GM and GLM muscles during P2 of the movement. The angular displacement of the KOAG was lower when compared with the HG. There was no statistical difference for the co-contraction and postural control data. CONCLUSIONS: The SLS analysis showed that EMG activity of the muscles TA, GM, and GLM was increased in the KOAG, but this pattern could be affected by fear of movement leading to reduced knee angular displacement.

Effects of an elastic resistance band exercise program on kinetics and muscle activities during walking in young adults with genu valgus: A double-blinded randomized controlled trial.

BACKGROUND: This double-blinded randomized-controlled-trial aimed to identify the effects of an elastic band resistance training on walking kinetics and muscle activities in young adults with genu valgus. METHODS: Forty-two male young adults aged 22.5(2.7) years with genu valgus were randomly allocated to two experimental groups. The intervention group (n = 21) conducted a 14-weeks elastic band resistance training. The control group was passive during the intervention period and received the same treatment after the post-tests. Pre and post training, ground reaction forces and lower limb muscle activities were recorded during walking. FINDINGS: Results revealed significant group-by-time interactions for peak medial ground reaction force and time-to-peak for posterior ground reaction force in favor of the intervention group (p < 0.012; d = 0.83-3.76). Resistance training with elastic bands resulted in significantly larger peak medial ground reaction force (p < 0.001; d = 1.45) and longer time-to-peak for posterior ground reaction force (p < 0.001; d = 1.85). Finding showed significant group-by-time interactions for peak positive free moment amplitudes in favor of the intervention group (p < 0.001; d = 1.18-2.02). Resistance training resulted in a lower peak positive free moment amplitude (p = 0.001; d = 1.46). With regards to muscle activities, the analysis revealed significant group-by-time interactions for rectus femoris and gluteus medius activities during the push-off phase in favor of the intervention group (p < 0.038; d = 0.68-0.89). Resistance training induced higher rectus femoris (p = 0.038; d = 0.84) and gluteus medius (p = 0.007; d = 0.54) activities. INTERPRETATION: This study proved the effectiveness of resistance training using elastic bands on kinetics and muscle activities during walking in male adults with genu valgus disorder. Given that this training regime is low cost, effective, and easy-to-administer, we suggest that it should be implemented as a rehabilitative or preventive means for young adults with genu valgus.

Body coordination during sit-to-stand in blind and sighted female children.

Detecting coordination pattern and coordination variability help us to find how joints organize collaboratively to perform sit-to-stand (STS) under restricted visual input. This experiment aimed to compare the coordination of the trunk, hip, knee, and ankle and its variability between individuals with long- and short-term restricted visual input during STS. Forty-five female children participated in this study, including fifteen congenitally blind (CB) children and 30 healthy children. The healthy children were divided randomly into two groups: one group in which the participants were instructed to keep their eyes open (EO) and another to keep their eyes closed (EC) for 20 min before the test. In the standing phase, CB children had a decreased ankle-knee vector angle on the nondominant (ND) side compared to that of healthy children. In the sagittal plane, a small coefficient-of-correspondences (CoC) was observed at seat-off (hip-trunk CoC on the dominant (D) side and ankle-hip CoC on the ND side) and in the preparation phase (ankle-hip CoC on the ND side and bilateral hip CoC). In the frontal plane (at the end: ankle-knee, in the standing phase: bilateral hip) a high CoC was observed (in the standing phase: knee-trunk CoC on the D side). The EC group had smaller CoCs at initiation event (knee-trunk and bilateral knee CoCs on both sides), the end event (ankle-knee and ankle-hip CoCs on the ND side), and in the standing phase (bilateral hip CoC) in the frontal plane than the other groups. The findings reveal that vector and CoC variables are altered because of long- and short-term restricted visual data and should be a focus in rehabilitation programs.

What is the influence of severity levels of knee osteoarthritis on gait initiation?

BACKGROUND: The anticipatory postural adjustments required for gait initiation have not yet been investigated in older adults with different levels of severity of knee osteoarthritis. This study aimed to evaluate the anticipatory postural adjustments adopted by older adults with different severity levels of knee osteoarthritis during gait initiation. METHODS: Sixty-seven older adults with knee osteoarthritis (mild, moderate, and severe levels) and 11 healthy older adults control were evaluated bilaterally with a force plate to analyze gait initiation. The center of pressure trajectory during gait initiation was divided into four phases: three anticipatory postural adjustments, and a locomotor phase. The length, duration, and velocity of each phase were calculated. FINDINGS: The results showed that during the right and left limbs swing forward, the severe and moderate knee osteoarthritis groups presented a significant reduction in the length of anticipatory postural adjustment phases, locomotion, duration, and velocity (P < 0.05). The severe knee osteoarthritis group presented a significantly higher body mass index (P < 0.003) than the other groups. However, just the healthy group presented a correlation between body mass index and anticipatory postural adjustments. INTERPRETATION: Our results demonstrated that older adults with severe and moderate levels of knee osteoarthritis adopt longer lasting and slower anticipatory postural adjustment phases, lower locomotion, and lower center of pressure displacement during gait initiation, suggesting that this population has adaptive strategy in performing gait initiation, which is significantly changed by the knee osteoarthritis severity level.

Effect of a corrective exercise program on gait kinetics and muscle activities in older adults with both low back pain and pronated feet: A double-blind, randomized controlled trial.

BACKGROUND: Low back pain is among the most common health problems seen in primary care. This study aimed to evaluate the effect of a corrective exercise program on GRF components, back pain, disability score, and muscle activities in back pain patients with pronated feet during walking. RESEARCH QUESTION: What is the effect of corrective exercise program on gait kinetics, back pain, disability score, and muscle activities in back pain patients with pronated feet during walking? METHODS: Thirty-six older adults with both back pain and pronated feet volunteered to participate in this study. They were randomly divided into two equal groups (experimental and control groups). Kinetic and EMG data were recorded during both pre and posttest. Visual analog pain scale and Roland-Morris disability questionnaire were used to assess back pain and disability values, respectively. RESULTS: In the experimental group but not in the control group, walking speed was significantly increased from pre to posttest (p = 0.001). The loading rate and free moment values were similar during both the pre and posttest (p > 0.05). In the experimental group but not in the control group, the disability score, back pain, tibialis anterior activity, and rectus abdominis activity were decreased during the posttest than that in the pretest (p < 0.001). SIGNIFICANCE: Higher walking speed, lower muscle activity and pain, lower disability score along with similar loading rate and free moments in the experimental group compared with the control group after the training protocol demonstrate the improvement of gait efficiency.

The relationship between running kinematics and the pelvic floor muscle function of female runners.

INTRODUCTION AND HYPOTHESIS: To date, no study has investigated the correlation between pelvic floor muscle function and urinary incontinence in female runners. The aim of the study was to investigate the relationship between pelvic floor muscle function and to correlate urinary leakage as measured by the modified pad test with kinematic variables of running. METHODS: The sample consisted of 11 incontinent and 17 continent runners. On day 1, they performed a maximum velocity test on a treadmill using an incremental protocol. Their pelvic floor muscles were evaluated using vaginal palpation and manometry, and the adapted pad test was used to evaluate the severity of urinary incontinence. Then, running kinematics were evaluated on a treadmill using a circuit camera to capture vertical displacement, knee flexion during the load response phase, and the initial contact of the foot with the ground for subsequent analysis. The pad test was performed during the kinematic evaluation. RESULTS: The vaginal squeeze pressure of the continent group (mean = 43.40 mmHg, SD = 21.75) was higher in descriptive terms than that of the incontinent group (mean = 38.94 mmHg, SD = 31.08), but the difference was not statistically significant (p = 0.66). There was an association between the weekly training load and urinary leakage. No associations were found between pelvic floor muscle function or urinary leakage and the kinematic variables. CONCLUSIONS: Despite the correlation between the weekly training load and the severity of urinary leakage, no relationships were found between pelvic floor muscle functioning and the kinematics of running.

Do the center of mass strategies change with restricted vision during the sit-to-stand task?

BACKGROUND: The relationship between the visual sensory and center-of-mass characteristics during the sit-to-stand task is not well documented. Do the center of mass strategies change with restricted vision during the sit-to-stand task? METHODS: The participants in this study were fifteen girls with congenital blindness (age (94.6 (5.6) months), mass (25.6 (2.0) kg), and height (1.3 (0.0) m)) and 30 healthy girls with no visual impairment who were divided randomly into two groups. The two experimental condition groups consisted of one in which the participants were assigned to keep their eyes open (age (95.8 (5.4) months), by mass (26.1 (5.1) kg), and by height (1.3 (0.0) m)) and the other in which the participants were assigned to keep their eyes closed (age (93.8 (0.0) months), by mass (24.2 (0.0) kg), and by height (1.1 (0.0) m)) for 20 min before the test. The center-of-mass displacement of the foot, leg, and thigh were calculated for dominance and non-dominance during the sit-to-stand performance at initiation, seat-off, and end events. FINDINGS: Congenital blindness was associated with the non-dominant center-of-mass displacement of the foot increasing upwards during all events (initiation, p = 0.025; seat-off, p = 0.036; end, p = 0.034), as well the non-dominant center of mass of the foot moving anteriorly during the initiation point (p = 0.016). In addition, the center-of-mass displacements for the dominant and non-dominant feet (initiation, p = 0.006, and p = 0.016; seat-off, p = 0.006, and p = 0.014; end, p = 0.006, and p = 0.013, respectively) and legs (16.98%, p = 0.024, d = 0.95; and 17.88%, p = 0.032, d = 0.99, respectively) in the eyes-closed group shifted to a forward direction, and the center of mass of the non-dominant foot (initiation, p = 0.024; seat-off, p = 0.021; end, p = 0.012) moved significantly upwards. Furthermore, the whole body center of the mass velocity (anterior-posterior axis (initiation, p = 0.042; seat-off, p = 0.006; end, p = 0.005)) in the eyes-closed group was smaller than that in the eyes-open group. INTERPRETATION: The findings show that the sit-to-stand center of the mass components in blind children may have clinical importance for the rehabilitation of these subjects.

Is it possible to stabilize the trunk using rhythmic stabilization in the upper limb? A cross-sectional study of asymptomatic individuals.

Objective: The study aim was to evaluate the immediate effect of rhythmic stabilization on local and distant muscles involved in a functional reach. Method: Prospective, observational cross-sectional study. Eight right-handed and non-impaired individuals (4 females and 4 males) aged 18-24 years (21.5 ± 1.58 years) were evaluated. Bilateral electromyographic recording of the biceps brachii, triceps brachii, multifidus lumbar, and rectus abdominis muscles was performed during three different tasks. Task 1 involved functional reach, while Task 2 involved rhythmic stabilization followed by a functional reach. Task 3 was similar to Task 2, but with 3 repetitions before a functional reach. Results: The results showed no difference between the tasks or sides. However, an interaction was observed between each side and muscles, with greater activation of the right multifidus lumbar muscle. Conclusion: Rhythmic stabilization during the task of reaching promotes an increase of multifidus activity ipsilateral to its application. Thus, this particular technique of proprioceptive neuromuscular facilitation can be useful for improving stability of the trunk and can be used in clinical practice for this purpose. Level of Evidence: 5.

Kinematic and electromyographic analysis of school children gait with and without load in the backpack

AbstractIntroduction: Excessive load on the backpacks can lead to musculoskeletal injuries and gait alterations. The objective of this study was to analyze the electromyographic (EMG) activity in association to the kinematic during the stance and balance phases of gait performed with and without the use of the backpack. Methods Twelve volunteers have executed a gait cycle in 3 tasks: without the school backpack (SM), with a backpack with load equivalent to 10% (M10) and 20% (M20) of the body weight (BW). It was evaluated the ankle, knee and hip angular excursion (AE), linear displacement (LD) of the toe and ankle, knee, hip, shoulder, head and EMG activity of the tibialis anterior (TA), vastus medialis (VM), rectus abdominis (RA), gastrocnemius lateral (GL), biceps femoris (BF) and spinal erector (EE) muscles. Results In the LD in the stance phase there was an AP increase for the toe and ankle, hip and head (p<0.043). In the balance phase for VT (vertical) direction, the shoulder presented a smaller displacement as well as the toe, ankle, knee, hip, shoulder and head in the ML direction. In the AP direction, the toe displacement was smaller as well as the ankle (p < 0.038). The AE in both phases was smaller for the hip (p <0.006). In the balance phase the IEMG was higher for the RA (p = 0.034). Conclusion These results suggest that the transport of school backpacks with loads of more than 10%BW causes changes in the kinematic and in the muscular recruitment pattern.

Secondary hyperalgesia occurs regardless of unilateral or bilateral knee osteoarthritis involvement in individuals with mild or moderate level / A hiperalgesia secundária ocorre independentemente do envolvimento unilateral ou bilateral da osteoartrite de joelho em indivíduos com doença leve ou moderada

ABSTRACT Background: Secondary hyperalgesia in individuals with less severe levels of knee osteoarthritis remains unclear. The objective of this study was to measure the pressure pain threshold of individuals with mild or moderate knee osteoarthritis and compare with no osteoarthritis. Methods: Ten healthy controls and 30 individuals with mild or moderate knee osteoarthritis divided into two groups (unilateral and bilateral involvement) were included. Dermatomes in lumbar levels (L1, L2, L3, L4 and L5) and sacral level (S1 and S2), myotomes (vastus medialis, vastus lateralis, rectus femoris, adductor longus, tibialis anterior, peroneus longus, iliacus, quadratus lumborum, and popliteus muscles), and sclerotomes in lumbar levels (L1-L2, L2-L3, L3-L4, L4-L5 supraspinous ligaments), over the L5-S1 and S1-S2 sacral areas, pes anserinus bursae, and at the patellar tendon pressure pain threshold were assessed and compared between individuals with and without knee osteoarthritis. Results: Knee osteoarthritis groups (unilateral and bilateral) reported lower pressure pain threshold compared to the control group in most areas (dermatomes, myotomes, and sclerotomes). There were no between group differences in the supra-spinous ligaments and over the L5-S1 and S1-S2 sacral areas of the sclerotomes. No difference was seen between knee osteoarthritis. Conclusion: These findings suggest that individuals with mild to moderate knee osteoarthritis had primary and secondary hyperalgesia, independent of unilateral or bilateral involvement. These results suggest that the pain have to be an assertive focus in the clinical practice, independent of the level of severity or involvement of knee osteoarthritis.

RESUMO Introdução: A ocorrência de hiperalgesia secundária em indivíduos com níveis menos graves de osteoartrite de joelho ainda é incerta. O objetivo deste estudo foi medir o limiar de dor à pressão (LDP) de indivíduos com osteoartrite de joelho (OAJ) leve ou moderada e comparar com indivíduos sem osteoartrite. Métodos: Foram incluídos 10 controles saudáveis e 30 indivíduos com OAJ leve ou moderada, divididos em dois grupos (envolvimento unilateral e bilateral). Foi avaliado e comparado o LDP em dermátomos (L1, L2, L3, L4, L5, S1 e S2), miótomos (músculos vasto medial, vasto lateral, reto femoral, adutor longo, tibial anterior, fibular longo, ilíaco, quadrado lombar e poplíteo) e esclerótomos (ligamentos supraespinais L1-L2, L2-L3, L3-L4, L4-L5), sobre as áreas sacrais L5-S1 e S1-S2, bolsa anserina e tendão patelar entre os indivíduos com e sem OAJ. Resultados: Os grupos OAJ (unilateral e bilateral) relataram menor LDP em comparação com o grupo controle na maior parte das áreas (dermátomos, miótomos e esclerótomos). Não houve diferenças entre os grupos nos ligamentos supraespinais e ao longo das áreas sacrais L5-S1 e S1-S2 dos esclerótomos. Não foi observada qualquer diferença entre os indivíduos com OAJ. Conclusão: Esses achados sugerem que os indivíduos com OAJ leve a moderada tinham hiperalgesia primária e secundária, independentemente do acometimento unilateral ou bilateral. Esses resultados sugerem que a dor precisa ser um foco assertivo na prática clínica, independentemente do grau de gravidade ou envolvimento da OAJ.

Evaluation of musculoskeletal symptoms and of work ability in a higher education institution / Avaliação dos sintomas osteomusculares e da capacidade para o trabalho em uma instituição de ensino superior

Introduction Work-related musculoskeletal disorders (WMSDs) represent a significant object of study for the field of occupational health, as they can lead to absenteeism, compensation costs and different levels of functional disability. Nonetheless, there are few studies assessing WMSDs in public higher education institutions. Objective The present study aimed to investigate, describe and correlate musculoskeletal symptoms and work ability of staff members of the Federal University of Alfenas (Unifal-MG), in the state of Minas Gerais, Brazil. Materials and methods A descriptive and correlational study was conducted with 213 professors, 188 administrative technicians and 124 outsourced staff members using two self-administered questionnaires: the Work Ability Index (WAI) and the Nordic Musculoskeletal Questionnaire (NMQ). Results Most of the teaching staff presented good work ability 47.9% (n = 102). Among administrative technicians and outsourced staff, on the other hand, excellent work ability predominated, with 43.6% (n = 82 technicians) and 51.61% (n = 68 outsourced). The most affected region among professors and administrative staff was the neck/cervical area 36.15% (n = 77 professors); and 28.19% (n = 53 technicians). Among outsourced staff, the lower back was reported as the main source of pain, with 23.28% (n = 29). Conclusions The presence of pain interfered in the work ability of workers regardless of the affected region. Having another occupation outside the institution did not influence pain of self-assessed staff members. The work ability of Unifal-MG staff was classified as good or excellent; thus, we recommend preventive work for this population, directed at the physical and mental aspects of work activities in order to maintain or improve such rates. .

Introdução Os distúrbios osteomusculares relacionados ao trabalho (Dort) representam preocupação para a saúde ocupacional, uma vez que geram absenteísmo, custos com indenizações, além de diferentes graus de incapacidade funcional. Mesmo assim, são escassos os estudos que os tenham avaliado em instituições públicas de ensino superior. Objetivo Este trabalho buscou investigar, descrever e correlacionar os sintomas osteomusculares e a capacidade para o trabalho dos servidores da Universidade Federal de Alfenas (Unifal-MG), no estado de Minas Gerais. Materiais e métodos Estudo descritivo-correlacional, que caracterizou 213 professores, 188 técnicos administrativos e 124 funcionários terceirizados, por meio de dois questionários autoaplicáveis: o Índice de Capacidade para o Trabalho (ICT) e o Questionário Nórdico de Sintomas Osteomusculares (QNSO). Resultados A maioria dos professores apresentou boa capacidade para o trabalho 47,9% (n = 102). Já entre os técnicos administrativos e funcionários terceirizados, predominou ótima capacidade com 43,6% (n = 82 técnicos) e 51,61% (n = 68 terceirizados). As regiões mais acometidas por dor entre os professores e os técnicos administrativos foram o pescoço/região cervical 36,15% (n = 77 docentes); e 28,19% (n = 53 técnicos). Já a região lombar foi a que se destacou entre os terceirizados como a principal fonte de dor, 23,28% (n = 29). Conclusões A presença de dor interfere na capacidade de trabalho do indivíduo, independente da região acometida. A ocupação externa não influenciou o estado doloroso dos servidores autoavaliados. A capacidade dos colaboradores da Unifal-MG foi classificada como boa ou ótima, por isso sugere-se um trabalho preventivo, com abordagem nos aspectos físicos e mentais da atividade laboral, visando a manutenção ou melhoria desse índice. .