[Purpose] The purpose of this study was to investigate the changes in hip, knee and ankle kinematic variables of the lower extremities at different gait speeds. [Subjects and Methods] Forty healthy subjects who had no previous history of neurological, musculo-skeletal or other medical conditions that could affect gait were recruited. The subjects were asked to walk 10 m down a walkway at three different gait speeds: normal gait speed, and self-selected fast, and slow speeds. The experimental order was randomly chosen across these gaits. The hip, knee and ankle kinematic data were evaluated using a VICON 3D motion analysis system and force plates. [Results] The flexion peak and external rotation peak of the knee joint significantly increased with the increase of gait speed. The plantarflexion peaks of the ankle joint significantly increased with increase of gait speed. However, none of the kinematic data of the hip joint were significantly dependent on increase of gait speed. [Conclusion] The relationship of the knee and ankle joint can be described as coupling motion which is dependent on gait speed. Our present findings suggest that coupling motion of the knee joint and plantarflexion of the ankle joint significantly increase with increase of gait speed. These results will provide important insight into gait mechanisms for the evaluation of pathological populations.

[Purpose] This study investigated upper-extremity muscle activities in natural, ideal, and corrected head positions. [Subjects and Methods] Forty subjects with a forward head posture and rounded shoulder were recruited and randomly assigned to the natural head position group (n = 13), ideal head position group (n = 14), or corrected head position group (n = 13). Muscle activities were measured using a four-channel surface electromyography system at the sternocleidomastoideus, upper and lower trapezius, and serratus anterior muscles on the right side during an overhead reaching task. [Results] The muscle activities of the upper trapezius and serratus anterior differed significantly among head positions. Post hoc tests revealed significant differences between natural and ideal head positions, and natural and ideal head positions for both the upper trapezius and serratus anterior. [Conclusion] Recovery of normal upper trapezius and serratus anterior muscle functions plays an important role in correcting forward head posture and rounded shoulders.

OBJECTIVE:The major contributors to physical disability after stroke are the negative impairments related to loss of functional ability and muscle strength. The aim of this study was to examine the effects of close kinetic chain (CKC) exercise and open kinetic chain (OKC) exercise on muscle activation of the paretic lower limb and balance in chronic stroke subjects. METHODS: Thirty-three patients with chronic stroke of over 6 months were enrolled. They were randomly allocated to three groups: CKC exercise group (n = 11), OKC exercise group (n = 11), and control group (n = 11). CKC and OKC exercise groups were trained 5 times per week for 6 weeks. The control group maintained routine activities and did not participate in any regular exercise program. All subjects were measured on muscle activation of the paretic lower limb and balance. RESULTS: Muscle activation of rectus femoris (RF) and biceps femoris (BF)was significantly increased in both CKC exercise and OKC exercise groups, compared to the control group. However, muscle activation of gastrocnemius (GC) and tibialis anterior (TA) was significantly increased in only the CKC exercise group. Antero-posterior (A-P) andmedio-lateral (M-L) sway velocities (both with EO and EC) were decreased with the application of CKC exercise. CONCLUSION: These findings indicate that the CKC exercise can improve lower limb muscle strength, and balance in chronic stroke, and it may carry over into an improvement in functional performance.

[Purpose] This study examined whether transcranial direct current stimulation (tDCS) of both the pre-supplementary motor area (pre-SMA) and primary sensoriomotor cortex (M1) alters the response time in response inhibition using the stop-signal task (SST). [Methods] Forty healthy subjects were enrolled in this study. The subjects were randomly tested under the three: the pre-SMA tDCS, M1 tDCS, and Sham tDCS conditions. All subjects performed a SST in two consecutive phases: without or after the delivery of anodal tDCS over one of the target sites (pre-SMA or the M1) and under the Sham tDCS condition. [Results] Our findings demonstrated significant reductions in the stop processing times after the anodal tDCS over pre-SMA, and change response times were significantly greater under the pre-SMA tDCS condition compared to both the M1 tDCS condition and the Sham tDCS condition. There was no significant major effect after delivery of the tDCS for the go processing times observed among the three conditions. [Conclusion] Anodal tDCS of the pre-SMA or M1 during performance of the SST resulted in enhancement of the volitional stop movement in inhibitory control. Our results suggest that when concurrently applied with the SST, tDCS might be a useful adjuvant therapeutic modality for modulation of the response inhibition and its related dynamic behavioral changes between motor execution and suppression.

[Purpose] Assessment of posture is an important goal of physical therapy interventions for preventing the progression of forward head posture (FHP). The purpose of this study was to determine the inter- and intra-rater reliabilities of the assessment of FHP. [Subjects and Methods] We recruited 45 participants (20 male subjects, 25 female subjects) from a university student population. Two physical therapists assessed FHP using images of head extension. FHP is characterized by the measurement of angles and distances between anatomical landmarks. Forward shoulder angle of 54° or less was defined as FHP. Intra- and inter-rater reliabilities were estimated using Kendall’s Taub correlation coefficients. [Results] Intra-class correlation of intra-rater measurements indicated an excellent level of reliability (0.91), and intra-class correlation of inter-rater measurements showed a good level of reliability in the assessment of FHP (0.75). [Conclusion] Assessment of FHP is an important component of evaluation and affects the design of the treatment regimen. The assessment of FHP was reliably measured by two physical therapists. It could therefore become a useful method for assessing FHP in the clinical setting. Future studies will be needed to provide more detailed quantitative data for accurate assessment of posture.