• 융합정보논문지
• /
• 제8권6호
• /
• pp.59-66
• /
• 2018

보행 시 지면에 대한 수직력에 대한 전단력의 비율, 즉 보행자가 사용한 마찰계수(UCOF)는 미끄러짐 발생 가능성 있는 시점을 식별하는데 사용된다. 신발보행은 신발창 두께와 경도, 뒤꿈치 모양, 밑창 문양 등의 신발 디자인이 사용마찰계수를 변화시킬 것이다. 본 연구에서는 보행 시 신발 착용 유무에 따른 사용마찰계수(UCOF) 차이를 분석하기 위해 성인남녀 21명(여자 10명, 남자 11명, 나이: $25.2{\pm}2.3yrs$, 키: $165.6{\pm}7.2cm$, 몸무게: $62.2{\pm}7.8kg$)을 대상으로 보행속도, 지면반력, 사용마찰계수(UCOF) 최대 시점, CoP-CoM-수직선 각도의 차이를 알아보고, 사용마찰계수(UCOF)와의 상관관계를 분석하였다. 그 결과, 첫째, 보행 시 신발 착용으로 인해 체중수용기(제동기)의 더 이른 시점에 사용마찰계수가 최대치에 도달하고, 또 그 크기도 증가한다. 둘째, CoP-CoM의 Tangent 값과 사용마찰계수(UCOF1)와의 상관관계는 오른발 제동 초기시점(UCOF1_h)보다 추진 후기에 발생하는 왼발(다음발) 착지시점(UCOF2_h)에서 더 높은 상관관계를 보여, 제동기 보다는 추진기(다음 발 제동기)와의 연관성을 시사한다.

• 제어로봇시스템학회논문지
• /
• 제21권6호
• /
• pp.538-546
• /
• 2015

This paper describes an intelligent ankle assistive robot which provides assistive power to reduce ankle torque based on an analysis of ankle motion and muscle patterns during walking on level and sloped floors. The developed robot can assist ankle muscle power by driving an electric geared motor at the exact timing through the use of an accelerometer that detects gait phase and period, and a potentiometer to measure floor slope angle. A simple muscle assistive link mechanism is proposed to convert the motor torque into the foot assistive force. In particular, this mechanism doesn't restrain the wearer's ankle joint; hence, there is no danger of injury if the motor malfunctions. During walking, the link mechanism pushes down the top of the foot to assist the ankle torque, and it can also lift the foot by inversely driving the linkage, so this robot is useful for foot drop patients. The developed robot and control algorithm are experimentally verified through walking experiments and EMG (Electromyography) measurements.

• 대한족부족관절학회지
• /
• 제11권2호
• /
• pp.182-186
• /
• 2007

Purpose: We examined the relationship of interdigital neuroma occurring site and the surrounding structures, including the deep transverse metatarsal ligament (DTML) by cadaver study and clinical results. Materials and Methods: Seventeen fresh frozen cadavers study were done to evaluate the relationship of interdigital neuroma occuring site and the DTML at two phase of the gait cycle with 60 degree of metatarsophalangeal dorsiflexion and with 15 degrees of ankle dorsiflexion. We measured the distance from interdigital nerve bifurcation of the common digital nerve to anterior margin of the DTML and longitudinal length of DTML itself. Clinically, we checked the location of interdigital neuroma and DTML length during surgery in 32 feet. Results: In the second and third web space, the mean distance from bifurcation of the common digital nerve of foot to the anterior margin of DTML was 16.7 mm, 15.1 mm in the mid-stance position, and 15.9 mm. 14.6 mm in heel-off position. Second, Third web space ligament itself length were average 12.8 mm, 10.6 mm. Clinically, all of the cases of interdigital neuroma started at the bifurcation area of the common digital nerve and interdigital neuroma was average 7.5 mm (range; 6-11 mm). Conclusion: Interdigital neuroma were located more distally than DTML in both the mid-stance and heel off stage. The main lesion was located between metatarsal head and metatarsophalangeal joint and more distal than the DTML anterior margin.

• 대한의용생체공학회:의공학회지
• /
• 제32권1호
• /
• pp.61-73
• /
• 2011

The purpose of this study was to investigate changes in the center of pressure (COP), ground reaction force (GRF) and joint angles of elderly people and young people while stair-descent. The participants in this experiment were 5 elderly people and 5 young people, each of which was asked to descend stairs of three different heights (8 cm, 16 cm, and 32 cm). As they climbed down the stairs, they received vibration stimulation on the lower limb. The change of COP, GRF and joint angles were analyzed during the standing phase. COP decreased as the Achilles tendon and tibialis anterior tendon were vibrated. Vertical GRF increased as the Achilles tendon was vibrated, and the joint angle differed according to vibration stimulation conditions. These results mean that ankle joint, knee joint and hip joint were influenced by the vibrations on the lower limb as the participants descended the stairs. It was concluded that the vibration stimulation on the lower limb allowed the participants to efficiently climb down the stairs.

• 한국운동역학회지
• /
• 제18권4호
• /
• pp.49-57
• /
• 2008

이 연구는 고령자를 대상으로 탄성저항운동을 수행하였을 경우 운동 전 후로 보행 시 지면반력 신호 크기와 이들의 variability에 어떠한 영향을 미치는 가를 구명하고자 하였다. 이를 위하여 여성 고령자 12명을 대상으로 12주간 탄성저항운동을 실시하였으며, 운동 전 후로 보행 시 3방향 지면반력 신호의 주파수 크기와 variability 값을 산출하였다. FFT(fast Fourier transform)를 이용하여 주파수 분석을 하였으며, PSD(power spectral density)를 계산하였다. 총 대상자들의 변이 계수(SD/Mean*100)을 이용하여 집단 간 variability를 계산하였다. 그 결과 다음과 같은 결론을 얻었다. 지면반력 신호의 주파수 크기는 좌우 방향에서 운동 전보다 운동 후에 작은 값을 보였으며, 통계적으로도 유의한 차이(p<.05)가 나타났다. 지면반력 신호의 variability에서는 좌우 방향에서 운동 전보다 운동 후에 큰 값이 나타났으며, 통계적으로도 유의한 차이(p<.05)가 나타났다.

• 한국전문물리치료학회지
• /
• 제23권4호
• /
• pp.27-37
• /
• 2016

Background: In previous studies regarding flexible pes planus, Foot orthosis, special shoes have been used as interventions for correcting malalignment and intrinsic muscles strengthening exercise have been regarded as interventions for foot function and supporting medial longitudinal arch during walking. However, some recent studies reported that strengthening extrinsic muscles as well as intrinsic muscles is more effective and active intervention for flexible pes planus. In particular, the tibialis posterior muscle of foot extrinsic muscles plays essential roles in maintaining the medial longitudinal arch during dynamic weight bearing and balance. In addition this muscle acts longer than other supination muscles during the stance phase in the gait cycle. Objects: This study aimed to investigate the effect of foot intrinsic muscle and tibialis posterior muscle strengthening exercise for plantar pressure and dynamic balance in adults with flexible pes planus. Methods: 16 young flexible pes planus adults (7 males, 9 females) were recruited and were randomized into two groups. The experimental group performed foot intrinsic muscle and tibialis posterior muscle strengthening training, the control group performed only foot intrinsic muscle strengthening training. All groups received strengthening training for 30 minutes five times a week for six weeks. Results: The experimental group had significantly lower plantar pressure of medial heel area than the control group in stand (p<.05). The experimental group had significantly higher dynamic balance ability than control group (p<.05). Conclusion: The results of this study provide evidence to suggest that foot intrinsic muscle and tibialis posterior muscle of extrinsic muscle strengthening exercises may improve plantar pressure distribution and dynamic balance ability in adults with flexible pes planus.

• 한국전문물리치료학회지
• /
• 제27권4호
• /
• pp.227-232
• /
• 2020

Background: Hallux valgus (HV) is a foot deformity developed by mediolateral deviation of the first metatarsophalangeal joint. Although various foot-toe orthoses were used to correct the HV angle, verification of the effects of kinetics variables such as ground reaction force (GRF) through three-dimensional (3D) gait analysis according to the various type of orthoses for HV is insufficient. Objects: This study aimed to investigate the effect of soft and hard types of foot and toe orthoses to correct HV deformity on the GRF in individuals with HV using 3D motion analysis system during walking. Methods: Twenty-six subjects participated in the experiment. Participants had HV angle of more than 15° in both feet. Two force platforms were used to obtain 3D GRF data for both feet and a 3D motion capture system with six infrared cameras was used to measure exact stance phase point such as heel strike or toe off period. Total walk trials of each participant were 8 to 10, the walkway length was 6 m. Two-way repeated measures ANOVA was used to determine the effects of each orthosis condition on the various GRF values. Results: The late anteroposterior maximal force and a first vertical peak force of the GRF showed that the hard type orthosis condition significantly increased GRF compared to the other orthosis conditions (p < 0.05). Conclusion: There were significant effects in GRF values when wearing the hard type foot orthosis. However, the hard type foot orthosis was uncomfortable to wear during walking. Therefore, it is necessary to develop a new foot-toe orthosis that can compensate for these disadvantages.

• 한국콘텐츠학회논문지
• /
• 제10권2호
• /
• pp.268-276
• /
• 2010

본 연구의 목적은 경사로를 오르는 동안 슬관절 굴곡각도와 족저압의 차이를 각각 다른 경사도에 따라 분석하고자 하는 것이다. 24명의 건강한 성인 참가자들에게 각각의 경사도($0^{\circ},\;3^{\circ},\;6{\circ},\;9^{\circ}$)를 걷게 한 후, Parotec system을 이용하여 족저압을 측정하였으며, 걷는 모습을 캠코더로 녹화 한 후 Dartfish system을 이용하여 슬관절 각도를 분석하였으며, 수집된 데이터는 SPSS/PC 통계 프로그램을 이용하여 일원배치분산분석으로 분석하였다. 결과는 각 경사로에 따라 슬관절 굴곡 각도는 통계학적으로 유의한 차이가 나타났으며, 족저압은 좌측 하지의 발뒤꿈치 외측 부위(1번 감지기), 중족부 내측 부위(9번 감지기), 전족부 내측 부위(15번, 16번 감지기), 그리고 우측 하지에서는 발뒤꿈치 외측 부위(3번 감지기)에서 통계학적으로 유의한 차이를 보였다. 슬관절 각도가 $10{\sim}20^{\circ}$ 사이에서 발뒤꿈치 외측 부위 및 내측 부위의 족저압이 통계학적으로 유의하게 높게 나타났다.

• 대한기계학회논문집A
• /
• 제24권3호
• /
• pp.613-624
• /
• 2000

In this study, new design method of prosthetic foot was suggested which can evaluate the performance of prosthetic foot by implementing amputee's gait simulation using the finite element analysis. The basic shape of ESPF(Energy Storing Prosthetic Foot) was designed which is suitable for the below-knee amputee considering mechanical properties and kinematic properties. And, the performance evaluations were performed using the Taguchi method with orthogonal array L25. As a result, average main effect of factors for the ESPF's performance were calculated and then optimum condition of given shape was selected. Essential particulars for the performance evaluation from the simulation result were the quantity of external work needed in stance phase, the quantity of transferred energy from the ESPF through the knee, and the vertical displacement of knee at toe-off. Reasonable optimum condition was obtained from the using performance index. From this study, it was found that it is necessary for the design of ESPF to consider the geometrical data related to the magnitude of load on elastic material.

• 한국운동역학회지
• /
• 제27권1호
• /
• pp.35-43
• /
• 2017

Objective: The purpose of this study was to determine how gaze angle affects muscle activity and kinematic variables during treadmill walking and to offer scientific information for effective and safe treadmill training environment. Method: Ten male subjects who have no musculoskeletal disorder were recruited. Eight pairs of surface electrodes were attached to the right side of the body to monitor the upper trapezius (UT), rectus abdominis (RA), erector spinae (ES), rectus femoris (RF), bicep femoris (BF), tibialis anterior (TA), medialis gastrocnemius (MG), and lateral gastrocnemius (LG). Two digital camcorders were used to obtain 3-D kinematics of the lower extremity. Each subject walked on a treadmill with a TV monitor at three different heights (eye level; EL, 20% above eye level; AE, 20% below eye level; BE) at speed of 5.0 km/h. For each trial being analyzed, five critical instants and four phases were identified from the video recording. For each dependent variable, one-way ANOVA with repeated measures was used to determine whether there were significant differences among three different conditions (p<.05). When a significant difference was found, post hoc analyses were performed using the contrast procedure. Results: This study found that average and peak IEMG values for EL were generally smaller than the corresponding values for AE and BE but the differences were not statically significant. There were also no significant changes in kinematic variables among three different gaze angles. Conclusion: Based on the results of this study, gaze angle does not affect muscle activity and kinematic variables during treadmill walking. However, it is interesting to note that walking with BE may increase the muscle activity of the trapezius and the lower extremity. Moreover, it may hinder proper dorsiflexion during landing phase. Thus, it seems to reasonable to suggest that inappropriate gaze angle should be avoided in treadmill walking. It is obvious that increased walking speed may cause a significant changes in biomechanical parameters used in this study. It is recommended that future studies be conducted which are similar to the present investigation but using different walking speed.