The effect of muscle-biased manual therapy on shoulder kinematics, muscle performance, functional impairment, and pain in patients with frozen shoulder.

BACKGROUND: Frozen shoulder (FS) is characterized by restricted active and passive shoulder mobility and pain. PURPOSE: Compare the effect of muscle-biased manual therapy (MM) and regular physical therapy (RPT) in patients with FS. STUDY DESIGN: Pretest-post-test control group study design. METHODS: We recruited 34 patients with FS and compared the effect of 12-session MM and RPT. The outcome measures were scapular kinematics and muscle activation, scapular alignment, shoulder range of motion, and pain intensity. Two-way analysis of variance was used to examine the intervention effect with α = 0.05. RESULTS: Both programs resulted in similar improvements in pain and shoulder function. Compared to the RPT, MM resulted in increased posterior tilt (MM: 7.04°-16.09°, RPT: -2.50° to -4.37°; p = 0.002; ES = 0.261) and lower trapezius activation (MM: 260.61%-470.90%, RPT: 322.64%-313.33%; p = 0.033; ES = 0.134) during scaption, and increased posterior tilt (MM: 0.70°-15.16°, RPT: -9.66° to -6.44°; p = 0.007; ES = 0.205) during the hand-to-neck task. The MM group also showed increased GH backward elevation (MM: 37.18°-42.79°, RPT: 43.64°-40.83°; p = 0.004, ES = 0.237) and scapular downward rotation (MM: -2.48° to 6.80°, RPT: 1.93°-1.44°; p < 0.001; ES = 0.404) during the thumb-to-waist task, enhanced shoulder abduction (MM: 84.6°-102.3°, RPT: 85.1°-92.9°; p = 0.02; ES = 0.153), and improved scapular alignment (MM: 10.4-9.65 cm, RPT: 9.41-9.56 cm; p = 0.02; ES = 0.114). CONCLUSIONS: MM was superior to the RPT regarding scapular neuromuscular performance. Clinicians should consider adding muscle-biased treatment when treating FS.

Alterations in kinematics of temporomandibular joint associated with chronic neck pain.

BACKGROUND: Temporomandibular disorder (TMD) is an umbrella term for pain and dysfunction of the temporomandibular joint (TMJ) and its associated structures. Patients with TMD show changes in TMJ kinematics and masticatory muscle activation. TMD is commonly comorbid with non-specific chronic neck pain (NCNP), which may be one of the risk factors for TMD. OBJECTIVES: This study aimed to investigate whether patients with NCNP have altered TMJ kinematics and masticatory muscle activity. METHODS: This was a cross-sectional exploratory study including 19 healthy participants and 20 patients with NCNP but without TMD symptoms. TMJ kinematics was measured during mouth opening and closing, jaw protrusion and jaw lateral deviation. Surface electromyography was used to record the muscle activity of the anterior temporalis, masseter, sternocleidomastoid and upper trapezius while clenching. Furthermore, cervical posture, cervical range of motion (ROM) and pressure-pain threshold of the neck and masticatory muscles were measured. RESULTS: Compared with the healthy group, the NCNP group showed significantly reduced upper cervical rotation ROM (p = .041) and increased condylar path length (p = .02), condylar translation (opening p = .034, closing p = .011) and mechanical pain sensitivity of the upper trapezius (p = .018). Increased condylar translation was significantly correlated with reduced upper cervical mobility and poor cervical posture (r = -0.322 to -0.397; p = .012-.046). CONCLUSION: Increased condylar translation and path length in patients with NCNP may indicate poor control of TMJ articular movement, which may result from neck pain or may be a compensation for limited neck mobility. Evaluation of excessive TMJ translation may be considered in patients with NCNP.

Immunopathogenesis of Acute Flare of Chronic Hepatitis B: With Emphasis on the Role of Cytokines and Chemokines.

Acute flares (AFs) of chronic hepatitis B usually occur during the immune-active stage (both immune clearance phase and immune reactivation phase), as the host immune system tries to control the virus. Successful host immune control over viral replication is usually presented as hepatitis B surface antigen seroclearance; however, 20-30% individuals with chronic hepatitis B may encounter repeated AFs with accumulative liver injuries, finally leading to the development of cirrhosis and hepatocellular carcinoma. AF can also develop in other clinical situations such as organ transplantation, cancer chemotherapy, and under treatment for chronic hepatitis B or treatment for chronic hepatitis C in patients with co-infected hepatitis B/hepatitis C. Understanding the natural history and immunopathogenesis of AF would help develop effective strategies to eradicate the virus and improve the clinical outcomes of patients with chronic hepatitis B. In this review article, the immunopathogenesis of AF, and the involvement of innate and adaptive immune responses on the development of hepatitis B flare will be briefly reviewed, with the emphasis on the role of cytokines and chemokines.

Kinetic Chain Exercise Intervention Improved Spiking Consistency and Kinematics in Volleyball Players With Scapular Dyskinesis.

ABSTRACT: Chang, C-C, Chang, C-M, and Shih, Y-F. Kinetic chain exercise intervention improved spiking consistency and kinematics in volleyball players with Scapular Dyskinesis. J Strength Cond Res 36(10): 2844-2852, 2022-Scapular dyskinesis (SD) is a common problem among volleyball players with chronic shoulder pain. This randomized controlled study examined the effectiveness of kinetic chain (KC) training on neuromuscular performance of the scapula and trunk during volleyball spikes. Forty volleyball players with SD and chronic shoulder pain received 4 weeks of KC training or the conventional shoulder exercise training (CT). Shoulder pain was assessed using the visual analogue scale (VAS) every week. The kinematics and muscle activation of the shoulder and upper trunk, and proprioceptive feedback magnitude (PFM) for scapular movement consistency, were recorded at the maximum shoulder flexion (T1) and ball contact (T2) during spiking tasks. The two-way repeated measures analysis of variances was used to assess the between-group differences before and after the intervention. The results showed a significant time by group interaction for the upper trunk rotation ( p < 0.001) and PFM ( p = 0.03) at T2. The post-hoc test indicated that the KC group significantly increased contralateral rotation of the upper trunk (9.63 ± 4.19° vs. -4.25 ± 10.05°), and improved movement consistency (error: 8.88 ± 11.52° vs. 19.73 ± 12.79°) at T2 compared with the CT group. Significant time effects were also identified for VAS, scapular upward rotation (T1 and T2), upper trunk contralateral side-bending and PFM at T1, and upper trunk contralateral rotation at T2. In conclusion, both KC and CT training would relieve shoulder pain and improve scapular and trunk movement, whereas the KC program was more effective for increasing scapular movement consistency and upper trunk rotation during volleyball spikes.

Effects of Kinesio tape on supporting medial foot arch in runners with functional flatfoot: a preliminary study.

This study aimed to evaluate the anti-pronation effects of Kinesio tape on flexible flatfoot during running. Nine volunteers participated in a crossover trail of two conditions: with Kinesio tape (KT) or without taping (NT). The running consisted of 9 stages of different inclines on a treadmill over 28 minutes. Navicular drop distance (NDD) was measured before and after the running. Electromyography, the relative plantar pressure, Rating of Perceived Exertion and Visual Analogue Scale were recorded at each stage. After the application of Kinesio tapes over the tibialis posterior and transverse arch, the NDD reduced significantly and the relative posterior pressure reduced during stage 8. Without taping, the NDD decreased slightly after exercise. Comparing between conditions, the tibialis anterior were more activated with Kinesio tape in stages 4 and 5. During the latter half of the running, the medial gastrocnemius and peroneus longus reduced their activity in the KT and NT conditions respectively. In conclusion, the Kinesio tapes intended to facilitate the tibialis posterior and reinforce the transverse arch can reduce NDD in individuals with flexible flatfoot immediately after application, and increase muscle activity of their tibialis anterior during the first 15 minutes of the running.

Can short-term effectiveness of anti-pronation taping predict the long-term outcomes of customized foot orthoses: developing predictors to identify characteristics of patients with plantar heel pain likely to benefit from customized foot orthoses.

BACKGROUND: Foot orthoses are widely used to manage plantar heel pain (PHP). However, the evidence concerning the effect of foot orthoses on PHP is not conclusive. The study aims to identify the characteristics of patients with PHP likely to achieve a positive outcome after customized foot orthoses and to verify the concept that patients who respond positively to anti-pronation taping would achieve a positive prognosis after wearing foot orthoses for six months. METHODS: This is a prospective observational cohort study. Seventy-four patients with PHP underwent a baseline examination and received anti-pronation taping to their painful feet. The taping effects on pain and function were assessed at the 7-day follow-up visit. Then, all patients received an intervention for their PHP with customized foot orthoses for six months. Outcome was assessed with a numeric pain rating scale, the patient-specific functional scale, the foot function index, and the global rating of perceived change. Significant reduction of pain, increase of function, and perception of a meaningful improvement were considered a positive response. RESULTS: Of 74 patients, 49 had a positive response to the customized foot orthosis treatment. Five predictors were identified: (1) the average pain intensity decreased by over 1.5 points with taping, (2) the range of ankle plantarflexion > 54 degrees, (3) the strength of ankle plantarflexors on the symptomatic side was equal to or stronger than that on the other side, (4) the range of hip internal rotation < 39 degrees, and (5) the range of hip external rotation > 45 degrees. The presence of three or more predictors increased the rate of achieving positive outcome from 66 to 89%. CONCLUSIONS: The predictors of customized foot orthosis outcome in patients with PHP are related to several physical measures of a lower extremity. Findings of the study can be used to screen and select patients with PHP for foot orthosis intervention. Moreover, patients who respond positively to anti-pronation taping would also benefit from the customized foot orthoses. However, since there was no control group in the current study, it is inappropriate to draw conclusions about the effectiveness of the foot orthoses treatment. TRIAL REGISTRATION: The trial was retrospectively registered with the Australian and New Zealand Clinical Trials Registry (ACTRN 12617000119392 ).

Effects of Kinesiology Taping on Scapular Reposition Accuracy, Kinematics, and Muscle Activity in Athletes With Shoulder Impingement Syndrome: A Randomized Controlled Study.

CONTEXT: Scapular proprioception is a key concern in managing shoulder impingement syndrome (SIS). However, no study has examined the effect of elastic taping on scapular proprioception performance. OBJECTIVE: To investigate the immediate effect of kinesiology taping (KT) on scapular reposition accuracy, kinematics, and muscle activation in individuals with SIS. DESIGN: Randomized controlled study. SETTING: Musculoskeletal laboratory, National Yang-Ming University, Taiwan. PARTICIPANTS: Thirty overhead athletes with SIS. INTERVENTIONS: KT or placebo taping over the upper and lower trapezius muscles. MAIN OUTCOME MEASURES: The primary outcome measures were scapular joint position sense, measured as the reposition errors, in the direction of scapular elevation and protraction. The secondary outcomes were scapular kinematics and muscle activity of the upper trapezius, lower trapezius, and serratus anterior during arm elevation in the scapular plane (scaption). RESULTS: Compared with placebo taping, KT significantly decreased the reposition errors of upward/downward rotation (P = .04) and anterior/posterior tilt (P = .04) during scapular protraction. KT also improved scapular kinematics (significant group by taping effect for posterior tilt, P = .03) during scaption. Kinesiology and placebo tapings had a similar effect on upper trapezius muscle activation (significant taping effect, P = .003) during scaption. CONCLUSIONS: Our study identified the positive effects of KT on scapular joint position sense and movement control. Future studies with a longer period of follow-up and clinical measurement might help to clarify the clinical effect and mechanisms of elastic taping in individuals with SIS.

Viral Factors Affecting the Clinical Outcomes of Chronic Hepatitis B.

Chronic hepatitis B (CHB) exhibits a variety of clinical outcomes, ranging from spontaneous resolution of hepatitis B to severe adverse consequences, including the development of cirrhosis, hepatic failure, and hepatocellular carcinoma. The heterogeneous clinical courses of chronic hepatitis B virus (HBV) infection reflect the complex host-virus interactions, and point to the difficulty and necessity of identifying the patients at risk. With the advance of HBV virology, several viral factors have been found to be associated with the long-term clinical outcomes of CHB patients. Different viral factors probe different aspects of CHB. Integration of these viral factors may help to determine the disease state of patients more accurately, and identify the patients who require timely antiviral therapy to prevent the development of detrimental clinical outcomes. In this article, we will introduce the conventional and emerging viral factors that are associated with clinical outcomes and discuss their utility in a clinical setting.

The immediate effect of muscle release intervention on muscle activity and shoulder kinematics in patients with frozen shoulder: a cross-sectional, exploratory study.

BACKGROUND: Contractile tissue plays an important role in mobility deficits in frozen shoulder (FS). However, no study has assessed the effect of the muscle release technique on the muscle activation and kinematics in individuals with FS. The purposes of this study were to assess the differences in shoulder muscle activity and kinematics between the FS and asymptomatic groups; and to determine the immediate effects of muscle release intervention in the FS group. METHODS: Twenty patients with FS and 20 asymptomatic controls were recruited. The outcome measures included muscle activity of the upper and lower trapezius (UT and LT), infraspinatus (ISp), pectoralis major (PM), and teres major (TM), shoulder kinematics (humeral elevation, scapular posterior tilt (PT) and upward rotation (UR), shoulder mobility, and pain. Participants in the FS group received one-session of heat and manual muscle release. Measurements were obtained at baseline, and immediately after intervention. Multivariate analysis of variance was used for data analysis. The level of significance was set at α=0.05. RESULTS: Compared to the controls, the FS group revealed significantly decreased LT (difference =55.89%, P=0.001) and ISp muscle activity (difference =26.32%, P =0.043) during the scaption task, and increased PM activity (difference =6.31%, P =0.014) during the thumb to waist task. The FS group showed decreased humeral elevation, scapular PT, and UR (difference = 35.36°, 10.18°, 6.73° respectively, P <0.05). Muscle release intervention immediately decreased pain (VAS drop 1.7, P <0.001); improved muscle activity during scaption (UT: 12.68% increase, LT: 35.46% increase, P <0.05) and hand to neck (UT: 12.14% increase, LT: 34.04% increase, P <0.05) task; and increased peak humeral elevation and scapular PT during scaption (95.18°±15.83° to 98.24°±15.57°, P=0.034; 11.06°±3.94° to 14.36°±4.65°, P=0.002), and increased scapular PT during the hand to neck (9.47°±3.86° to 12.80°±8.33°, P=0.025) task. No statistical significance was found for other group comparisons or intervention effect. CONCLUSION: Patients with FS presented with altered shoulder muscle activity and kinematics, and one-session of heat and manual muscle release showed beneficial effects on shoulder muscle performance, kinematics, mobility, and pain. TRIAL REGISTRATION: Retrospectively registered on Jan 18, 2016 (ACTRN 12616000031460 ).

Investigating the Effects of Peripheral Electrical Stimulation on Corticomuscular Functional Connectivity Stroke Survivors.

BACKGROUND: Electrical stimulation (ES) in the periphery can induce brain plasticity and has been used clinically to promote motor recovery in patients with central nervous system lesion. Electroencephalogram (EEG) and electromyogram (EMG) are readily applicable in clinical settings and can detect real-time functional connectivity between motor cortex and muscles with EEG-EMG (corticomuscular) coherence. OBJECTIVE: The purpose of this study was to determine whether EEG-EMG coherence can detect changes in corticomuscular control induced by peripheral ES. METHODS: Fifteen healthy young adults and 15 stroke survivors received 40-min electrical stimulation session on median nerve. The stimulation (1-ms rectangular pulse, 100 Hz) was delivered with a 20-s on-20-s off cycle, and the intensity was set at the subjects' highest tolerable level without muscle contraction or pain. Both before and after the stimulation session, subjects performed a 20-s steady-hold thumb flexion at 50% maximal voluntary contraction (MVC) while EEG and EMG were collected. RESULTS: Our results demonstrated that after ES, EEG-EMG coherence in gamma band increased significantly for 22.1 and 48.6% in healthy adults and stroke survivors, respectively. In addition, after ES, force steadiness was also improved in both groups, as indicated by the decrease in force fluctuation during steady-hold contraction (-1.7% MVC and -3.9%MVC for healthy and stroke individuals, respectively). CONCLUSIONS: Our results demonstrated that EEG-EMG coherence can detect ES-induced changes in the neuromuscular system. Also, because gamma coherence is linked to afferent inputs encoding, improvement in motor performance is likely related to ES-elicited strong sensory input and enhanced sensorimotor integration.

Predictors for identifying patients with patellofemoral pain syndrome responding to femoral nerve mobilization.

OBJECTIVE: To identify the predictors for successful neurodynamic management in patients with patellofemoral pain syndrome. DESIGN: Prospective cohort, prediction rule study. SETTING: Hospital. PARTICIPANTS: Patients with patellofemoral pain syndrome (N=51) underwent clinical examination and measurement of physical parameters, including femoral slump test, lower-extremity alignment, flexibility and muscle strength, and functional level. INTERVENTION: Patients received 6 treatment sessions of femoral nerve mobilization within 2 weeks. MAIN OUTCOME MEASURES: Pain level during functional testing was assessed before and after the first and sixth session of treatment. Patients were then grouped into responder and nonresponder groups. Criteria for the responder group was a pain score decrease ≥50% or Global Rating Scale score ≥4. Chi-square and independent t tests were used to identify potential variables with a significance level of .10, and stepwise logistic regression was used to find predictors with a significance level of .05. RESULTS: Twenty-five patients responded to the initial treatment (immediate effect), and 28 patients responded after 6 sessions (longer-term effect). A positive femoral slump test was identified as the predictor for the immediate treatment effect. The prediction factors for the longer-term effect included responding to femoral nerve mobilization the first time and a bilateral difference in hip extension angles. Application of the clinical predictors improved the success rate to 90% for 1 treatment session and 93% for 6 treatment sessions. CONCLUSIONS: Clinicians could use the positive femoral slump test and a bilateral difference in hip extension angles during the femoral slump test to determine whether or not patients with patellofemoral pain syndrome might benefit from femoral nerve mobilization.

Translation, Cross-Cultural Adaptation, and Validation of the Traditional Chinese Version of the VISA-P Questionnaire.

Background: The Victorian Institute of Sport Assessment-Patella (VISA-P) questionnaire is a widely accepted instrument for measuring the severity of symptoms and pain in patients having sustained patellar tendinopathy. Purpose: To adapt the VISA-P questionnaire cross-culturally to a traditional Chinese version (VISA-P-Ch) and validate its psychometric properties. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: The VISA-P questionnaire was adapted to a traditional Chinese version following international recommended guidelines, including translation, synthesis, back translation, revision by expert committee, pretesting, and validation. The psychometric properties were tested in 15 healthy controls and 15 participants with patellar tendinopathy. Face validity was judged by the authors and participants. Known-groups validity was tested by comparing the VISA-P-Ch scores between symptomatic and asymptomatic participants using an independent t test. Concurrent validity was determined by comparing the Blazina classification of the participants against VISA-P-Ch scores using the Spearman correlation coefficient. Test-retest reliability was assessed by calculating the intraclass correlation coefficient (ICC) following a 24- to 48-hour interval. Internal consistency was determined by the Cronbach alpha. Results: The expert committee and participants reported good face validity of the VISA-P-Ch. Significantly higher scores were found in the control group than in the patellar tendinopathy group (98.47 ± 3.04 vs 65 ± 11.9; P < .001). Concurrent validity showed a high correlation between VISA-P-Ch and the Blazina classification system (r = -0.899; P < .01). The test-retest reliability was excellent (ICC = 0.964). Internal consistency was found to be good for both the first and second assessments (Cronbach α = 0.834 and 0.851). Conclusion: The VISA-P-Ch was proven to be a reliable and valid questionnaire with similar psychometric properties as the original VISA-P.

Scapula-focused exercises with or without biofeedback increase corticospinal excitability in recreational overhead athletes with shoulder impingement.

CONTEXT: Individuals with shoulder impingement syndrome (SIS) exhibit changed corticospinal excitability, scapular kinematics, and scapular muscle activation patterns. To restore the scapular kinematics and muscle activation patterns in individuals with SIS, treatment protocols usually include scapula-focused exercises, such as scapular orientation training and strength training. OBJECTIVE: To investigate whether these two types of scapular exercise can reverse the changed corticospinal excitability of recreational overhead athletes with SIS. DESIGN: Randomized Controlled Clinical Trial. SETTING: University laboratory. PATIENTS OR OTHER PARTICIPANTS: Forty-one recreational overhead athletes with SIS (n=20 in the scapular orientation group with age= 26.45±4.13 years; height= 171.85±7.88 cm; mass= 66.70±10.68 kg; n=21 in the strengthening group with age= 26.43±5.55 years; height= 171.62±5.87 cm; mass= 68.67±10.18 kg). INTERVENTIONS: Both groups performed a 30-minute training protocol consisting of three exercises to strengthen the lower trapezius and serratus anterior muscles without overactivating the upper trapezius. Participants in the scapular orientation group were instructed to consciously activate their scapular muscles with electromyographic biofeedback and cues, whereas the strengthening group did not have biofeedback or cues for scapular motion. MAIN OUTCOME MEASURES: Corticospinal excitability was assessed using transcranial magnetic stimulation. Scapular kinematics and muscle activation during arm elevation were also measured. RESULTS: After the training, both groups demonstrated a significant increase in motor evoked potentials in lower trapezius (P=0.004) and significant increases in scapular upward rotation (P=0.032), lower trapezius activation (P<0.001), and serratus anterior activation (P<0.001) during arm elevation. Moreover, the scapular orientation group showed higher lower trapezius activation levels during arm elevation following the training, compared with the strengthening group (P=0.028). CONCLUSIONS: With or without biofeedback and cues, scapula-focused exercises improved scapular control and increased corticospinal excitability. Adding biofeedback and cues for scapular control during exercise helped facilitate greater lower trapezius activation, and thus, feedback and cues are recommended during scapula-focused training.

Effects of early aquatic exercise intervention on trunk strength and functional recovery of patients with lumbar fusion: a randomized controlled trial.

This study investigated the effectiveness of an early aquatic exercise program on trunk muscle function and functional recovery of patients with lumbar fusion. Twenty-eight subjects were divided into two equal groups. Patients in the aquatic group performed two 60-min aquatic exercise sessions and three 60-min home exercise sessions per week for 6 weeks, whereas those in the control group performed five sessions of 60-min home exercises per week for 6 weeks. The primary outcomes were the Numerical Pain Rating Scale (NPRS) and Oswestry Disability Index (ODI), and the secondary outcomes were Timed Up and Go Test (TUGT), trunk flexor and extensor muscle strength, lumbopelvic stability, and lumbar multifidus muscle thickness measured pre- and post-intervention. Compared with participants in the control group, those in the experimental group showed significant improvement in NPRS, ODI, trunk extensor strength, lumbopelvic control, lumbar multifidus muscle thickness, and relative change in multifidus muscle thickness (significant time by group interactions, P < 0.05). Participants in both groups showed significant time effects (P < 0.001) for TUGT and trunk flexor strength outcome. Aquatic exercise combined with home exercise was superior to home exercise alone in reducing pain, disability and improving muscle strength, lumbopelvic stability, and lumbar multifidus muscle thickness.

Specificity of the femoral slump test for the assessment of experimentally induced anterior knee pain.

OBJECTIVE: To assess the specificity of the femoral slump test (FST) when assessing experimentally induced anterior knee pain. DESIGN: Cross-sectional, exploratory study. SETTING: Research laboratory. PARTICIPANTS: Asymptomatic subjects (N=12; 6 men; 6 women) for the study. An experimental pain model was used to simulate anterior knee pain by injecting .25 mL of hypertonic saline solution (5% NaCl) into the medial infrapatellar fat pad. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: The changes in pain intensity and diameter after applying the structure differential maneuver (neck flexion/extension) during the FST were recorded and analyzed. RESULTS: Results revealed that the structure differential maneuver of the FST did not alter the pain intensity or diameter in 9 (neck extension) and 10 (neck flexion) out of 12 subjects, which meant that the FST provided appropriate testing responses in 75% to 83% cases when the anterior knee pain did not originate in neural tissues. CONCLUSIONS: The FST had a specificity of more than .75 when detecting nerve mechanosensitivity problems of anterior knee pain.

Lower extremity kinematics in children with and without flexible flatfoot: a comparative study.

BACKGROUND: A high percentage of young children present with flatfeet. Although the percentage of those with flatfeet declines with age, about 15% of the population maintains a flat arch. A reduction in longitudinal arch height usually combines with excessive subtalar joint pronation and may be related to other musculoskeletal problems of the lower extremity kinetic chain. The purpose of this study is to describe and compare the lower extremity kinematics between children with normal arches and those with flexible flatfeet, with the intent of providing practical information for decision making when treating children with flexible flatfeet. METHODS: Twenty children with flexible flatfeet (years age mean (SD), 9.7 (0.9) years) and 10 children with normal arches (yeas age mean (SD), 9.6 (1.2) years) were included. Kinematic data (maximum and minimum angles, and movement range, velocity, and excursion) of the hip, knee and rearfoot were collected during walking using Liberty Electromagnetic Tracking System. Kinematic variables were compared between the normal arches and flexible flatfeet groups using repeated measures mixed effects ANOVA. RESULTS: Movement patterns at the hip, knee and ankle joints were similar between children with flexible flatfeet and with normal arches. The results of ANOVA showed no significant main effect or interaction in any of the kinematic variables (P ≥ 0.05). CONCLUSIONS: This study identified no kinematic adaptation during walking in children with flexible flatfoot. We suggested that future research should take the influence of the mid-foot and forefoot into consideration when examining lower extremity kinematics in children with flexible flatfoot.

Effects of Different Pedaling Positions on Muscle Usage and Energy Expenditure in Amateur Cyclists.

BACKGROUND: Inappropriate cycling positions may affect muscle usage strategy and raise the level of fatigue or risk of sport injury. Dynamic bike fitting is a growing trend meant to help cyclists select proper bikes and adjust them to fit their ergometry. The purpose of this study is to investigate how the "knee forward of foot" (KFOF) distance, an important dynamic bike fitting variable, influences the muscle activation, muscle usage strategy, and rate of energy expenditure during cycling. METHODS: Six amateur cyclists were recruited to perform the short-distance ride test (SRT) and the graded exercise tests (GXT) with pedaling positions at four different KFOF distances (+20, 0, -20, and -40 mm). The surface electromyographic (EMG) and portable energy metabolism systems were used to monitor the muscle activation and energy expenditure. The outcome measures included the EMG root-mean-square (RMS) amplitudes of eight muscles in the lower extremity during the SRT, the regression line of the changes in the EMG RMS amplitude and median frequency (MF), and the heart rate and oxygen consumption during the GXT. RESULTS: Our results revealed significant differences in the muscle activation of vastus lateralis, vastus medialis, and semitendinosus among four different pedaling positions during the SRT. During GXT, no statistically significant differences in muscle usage strategy and energy expenditure were found among different KFOF. However, most cyclists had the highest rate of energy expenditure with either KFOF at -40 mm or 20 mm. CONCLUSIONS: The KFOF distance altered muscle activation in the SRT; however, no significant influence on the muscle usage strategy was found in the GXT. A higher rate of energy expenditure in the extreme pedaling positions of KFOF was observed in most amateur cyclists, so professional assistance for proper bike fitting was recommended.

Altered corticospinal excitability of scapular muscles in individuals with shoulder impingement syndrome.

The purpose of this study is to assess and compare corticospinal excitability in the upper and lower trapezius and serratus anterior muscles in participants with and without shoulder impingement syndrome (SIS). Fourteen participants with SIS, and 14 without SIS were recruited through convenient sampling in this study. Transcranial magnetic stimulation assessment of the scapular muscles was performed while the participants were holding their arm at 90 degrees scaption. The motor-evoked potential (MEP), active motor threshold (AMT), latency of MEP, cortical silent period (CSP), activated area and center of gravity (COG) of cortical mapping were compared between groups using the Mann-Whitney U tests. The SIS group demonstrated following significances, higher AMTs of the lower trapezius (SIS: 0.60 ± 0.06; Comparison: 0.54 ± 0.07, p = 0.028) and the serratus anterior (SIS: 0.59 ± 0.04; Comparison: 0.54 ± 0.06, p = 0.022), longer CSP of the lower trapezius (SIS: 62.23 ± 22.87 ms; Comparison: 45.22 ± 14.64 ms, p = 0.019), and posteriorly shifted COG in the upper trapezius (SIS: 1.88 ± 1.06; Comparison: 2.76 ± 1.55, p = 0.048) and the serratus anterior (SIS: 2.13 ± 1.02; Comparison: 3.12 ± 1.88, p = 0.043), than the control group. In conclusion, participants with SIS demonstrated different organization of the corticospinal system, including decreased excitability, increased inhibition, and shift in motor representation of the scapular muscles.

Application of wedged foot orthosis effectively reduces pain in runners with pronated foot: a randomized clinical study.

OBJECTIVE: To examine the effects of foot orthosis intervention during a 60-minute running test in pronated-foot runners with overuse knee or foot pain during running. DESIGN: A randomized, controlled design. SETTING: Sports gym. PARTICIPANTS: Twenty-four runners with pronated foot who experienced pain over anterior knee or foot region during running were recruited and randomized into the treatment, or the control, group. INTERVENTIONS: A soft insole with a semi-rigid rearfoot medial wedge was given to the treatment group, and a soft insole without corrective posting was applied to the control group. OUTCOME MEASURES: The immediate and short-term effects of orthosis application on incidence of pain, pain intensity and onset time were evaluated using the 60-minutes treadmill test. RESULTS: Immediately after wearing the foot orthosis, pain incidence reduced in the treatment group but not in the control group (P = 0.04). After two weeks, seven (58%) subjects in the treatment group and one (8%) in the control group were free of pain during the test (P = 0.01). The pain intensity score decreased significantly after orthosis application, from 35.5 to 17.2 (immediate effect, P = 0.014), then to 12.3 (short-term effect, P < 0.001). CONCLUSION: The rearfoot medially-wedged insole was a useful intervention for preventing or reducing painful knee or foot symptoms during running in runners with pronated foot.

Influence of pain location and hand dominance on scapular kinematics and EMG activities: an exploratory study.

BACKGROUND: Assessment of three-dimensional kinematics and electromyography (EMG) activities is common in patients with chronic neck pain. However, the effect of hand dominance and neck pain location on the measurement of movement and EMG characteristics is still unclear. Therefore, the purpose of this study was to investigate the effect of neck pain location and arm dominance on the scapular kinematics and muscle EMG activities in patients with chronic neck pain. METHODS: Thirty subjects (10 males, 20 females; mean age (sd): 38 (11.9) years) with chronic neck pain for more than 3 months were recruited. The scapular kinematics and EMG activity of the upper trapezius and sternocleidomastoid muscles were measured during the bilateral arm elevation task. The three-way repeated measures ANOVA was used to examine the effect of neck pain location and hand dominance on the measurement of kinematics and EMG muscle activities. RESULTS: The movement of scapular posterior tilt was significantly influenced by arm dominance (P = 0.001) and by the interaction of arm dominance and elevation angle (P = 0.002). The movement of scapular upward/downward rotation was affected by the interaction of arm dominance and elevation angle (P = 0.02). The location of pain did not show any significant influence on the scapular movement and muscle activities. CONCLUSIONS: Hand dominance could have an influence on the scapular kinematics, which should be taken into consideration when describing and comparing neuromuscular characteristics in individuals with chronic neck pain.