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Context: A winged scapula (WS) is associated with faulty posture caused by weakness of the serratus anterior (SA), which mainly acts as a scapular stabilizer muscle. It is important to accurately assess and train the SA muscle with a focus on scapula stabilizers during musculoskeletal rehabilitation of individuals with a WS. Objective: The authors examined muscle activity in the SA and pectoralis major (PM), upper trapezius (UT), and anterior deltoid (AD) as well as shoulder protraction strength during isometric shoulder protraction in individuals with and without a WS. Design: Cross-sectional study. Setting: A clinical biomechanics laboratory. Participants: In total, 27 males with no shoulder, neck, or upper-extremity pain participated. Main Outcome Measures: Isometric shoulder protraction strength was collected and surface electromyography used to measure the activity of the SA, PM, UT, and AD muscles and selective SA activity ratio to other shoulder muscles. Results: Electromyography activity of the SA muscle and shoulder protraction strength were significantly lower in individuals with a WS compared with the non-WS group (P <.05). In contrast, PM muscle activity and the PM-to-SA, UT-to-SA, and AD-to-SA ratios were significantly greater in individuals with a WS than in individuals without winging (P <.05). Conclusions: Isometric shoulder protraction for measuring SA strength in individuals with a WS should focus on isolated muscle activity of the SA, and SA strengthening exercises are important for individuals with a WS. [ABSTRACT FROM AUTHOR]

BACKGROUND: The abductor hallucis (AbH) is a key muscle in the stability of the foot by supporting the medial longitudinal arch (MLA). Individuals with flat foot show a flattening of the MLA with a decreased selective AbH activity relative to the other foot extrinsic muscles during functional movement. OBJECTIVE: To examine the selective muscle activity of the abductor hallucis (AbH) during single-leg mini-squat (SMS) in subjects with flat foot and normal individuals. METHODS: Twenty-four healthy adults (13 men and 11 women) with flat or normal feet participated in this study. All subjects performed single minisquat (SMS), and data were collected using sEMG from the AbH, TA, and GCM during SMS. RESULTS: An inter-gender comparison of the EMG data revealed no difference. The EMG activity of the AbH in individuals with flat foot was significantly lower than that of individuals with normal feet. Moreover, the AbH/TA ratio in subjects with flat foot, , was significantly lower than that in subjects with normal feet. CONCLUSION: In a clinical setting, clinicians should focus on strengthening exercises of the AbH muscle due to reduced activation of the AbH muscle in individuals with flat foot. The selective muscle activity of the AbH muscle during SMS should be emphasized. [ABSTRACT FROM AUTHOR]

BACKGROUND: The abdominal draw-in maneuver (ADIM) has been suggested to increase trunk stabilizing muscle activity; however, no study has identified the effects of the ADIM on trunk muscles and trunk movements during lifting and lowering (L & L) tasks. OBJECTIVE: We examined the effects of the ADIM on transversus abdominis (TrA) thickness during standing, the activity of the TrA, internal oblique (IO) and multifidus (MF), and the kinematics of the lumbo-pelvic-hip complex during L & L tasks. METHODS: Fifteen male participants practiced expirations without and with the ADIM using ultrasound biofeedback. After training for each condition, the participants performed expirations with and without the ADIM in the standing position and during L & L tasks. TrA thickness during the standing position and muscular activities (EMG) of the bilateral TrA/IO and MF, and the peak angle of the lumbo-pelvic-hip complex in the sagittal plane during L & L tasks were measured. RESULTS: TrA thickness during standing was increased with expiration with ADIM compared to that without the ADIM (p < 0.05). When performing expiration with the ADIM, increased activity of the TrA/IO and MF was observed by EMG, as well as peak pelvic anterior tilt and hip flexion with decreased peak lumbar flexion during L & L tasks (p < 0.05). CONCLUSIONS: The ADIM could be an effective strategy to improve trunk stability and reduce lumbar flexion during L & L tasks. [ABSTRACT FROM AUTHOR]

Abstract Background During maximal isometric protraction, it is important to determine the optimal resistance intensity in subjects with a winged scapula, for inducing isolated activity of the serratus anterior against the pectoralis major, which is activated as a synergistic muscle. The aim of the present study was to determine electromyographic activities of the serratus anterior and pectoralis major muscles during isometric shoulder protraction at different levels in subjects with and without a winged scapula. Methods Thirty male subjects performed isometric shoulder protraction in a sitting position at different resistance intensity levels (100%, 80%, and 60% of maximal protraction strength). Surface electromyographic data of the serratus anterior and pectoralis major muscles were gathered simultaneously using fixed instrumentation to measure isometric shoulder protraction. Findings Muscle activity of the serratus anterior in subjects without a winged scapula was significantly greater than that of subjects with a winged scapula across all three conditions, whereas muscle activity of the pectoralis major was lower in subjects without a winged scapula. In addition, winged scapula muscle activity corresponding to maximal protraction was significantly greater than that in the submaximal condition. Interpretation In a clinical setting, submaximal resistance can be more optimal than maximal effort during isometric shoulder protraction in individuals with a winged scapula. Highlights • Individuals with winged scapula showed decreased serratus anterior muscle activity. • Selective activation of the serratus anterior increased at submaximal intensity. • A submaximal effort level is recommended for individuals with a winged scapula. [ABSTRACT FROM AUTHOR]