The effects of smartphone multitasking on gait and dynamic balance.

[Purpose] This study was performed to analyze the influence of smartphone multitasking on gait and dynamic balance. [Subjects and Methods] The subjects were 19 male and 20 female university students. There were 4 types of gait tasks: General Gait (walking without a task), Task Gait 1 (walking while writing a message), Task Gait 2 (walking while writing a message and listening to music), Task Gait 3 (walking while writing a message and having a conversation). To exclude the learning effect, the order of tasks was randomized. The Zebris FDM-T treadmill system (Zebris Medical GmbH, Germany) was used to measure left and right step length and width, and a 10 m walking test (10MWT) was conducted for gait velocity. In addition, a Timed Up and Go test (TUG) was used to measure dynamic balance. All the tasks were performed 3 times, and the mean of the measured values was analyzed. [Results] There were no statistically significant differences in step length and width. There were statistically significant differences in the 10MWT and TUG tests. [Conclusion] Using a smartphone while walking decreases a person's dynamic balance and walking ability. It is considered that accident rates are higher when using a smartphone.

Relationship between position sense and reposition errors according to the degree of upper crossed syndrome.

[Purpose] The purpose of this study was to compare reposition errors in subjects with upper crossed syndrome to examine the effects of upper crossed syndrome on position senses. [Subjects and Methods] A sample population of 60 subjects was randomly divided into three groups of 20: a normal group, a mild group, a moderate group. A cervical range of motion device was attached to the head of each subject using straps and the reposition errors of cervical flexion, extension, right lateral flexion, left lateral flexion, right rotation and left rotation were measured. [Results] The normal group showed smaller reposition errors than the mild group and the mild group showed smaller reposition errors than the moderate group but none of the differences among the three groups was significant. [Conclusion] Reposition errors increased in the order of the normal, mild, moderate group but the differences were not significant. In addition, the degree of the subjects' postural misalignment was higher in the moderate than in the mild group. These results demonstrate that cervical spine position sense declines as postural misalignment becomes more severe.

Maximum force and the center of pressure trajectory length according to foot angles during stair walking.

[Purpose] Walking with the feet turned inward or outward often causes issues for the people with these walking patterns. The purpose of this study was to examine the influence of in-toeing and out-toeing on maximum force and the center of pressure (COP) trajectory length during stair walking. [Subjects and Methods] The subjects were 30 female university students without orthopedic diseases of the foot. The foot angle was divided into three types: in-toeing, normal, and out-toeing. A plantar pressure measurement instrument was used, and the maximum force was obtained by dividing the foot into six regions covering the anterior medial-lateral, middle medial-lateral, and posterior medial-lateral regions. The COP trajectory length was statistically calculated by measuring the medial-lateral, anterior-posterior, and total travel distances. [Results] During stair climbing, the maximum force was significantly different in the anterior lateral region. During stair descending, the maximum force was significantly different in the anterior lateral, middle medial, middle lateral, posterior medial, and posterior lateral regions. The COP trajectory length showed a statistically significant difference in the medio-lateral travel distance. [Conclusion] Walking with abnormal foot angles causes deformed foot structures and can result in musculoskeletal disabilities in the long term. Therefore, therapeutic intervention is required to maintain normal foot angles.

Changes in angular kinematics of the paretic lower limb at different orthotic angles of plantar flexion limitation of an ankle-foot-orthosis for stroke patients.

[Purpose] An ankle-foot-orthosis (AFO) is an assistive brace that allows stroke patients to achieve an independent gait. Therefore, we examined whether or not the orthotic angle for plantar flexion limitation affects the kinematic parameters of the hip and knee joints on the affected side of patients with stroke. [Subjects and Methods] Fifteen patients with chronic hemiplegia were recruited for this study. Kinematic three-dimensional data was acquired, while patients walked along a walkway wearing AFOs under five different conditions of 0°, 5°, 10°, 15°, and 20° of plantar stop limitation angle in the orthotic joint. Peak angles of the hip and knee joints on the affected side were analyzed. [Results] At the peak angle of the knee joint, statistically significant differences were found only at mid-stance in the sagittal plane and the horizontal plane. However, no significant differences were observed among any of the orthotic limitation angles in the frontal plane. [Conclusion] According to the results, an orthotic limitation angle of more than 10° elicits changes in the knee joint angle at mid-stance in the sagittal and horizontal planes. This study provided basic data on postural changes of patients with stroke.