• The Journal of Korean Physical Therapy
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• v.27 no.5
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• pp.304-310
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• 2015

Purpose: The purpose of this study was to examine the change in the kinematics and kinetics of the knee joint depending on high-heeled shoes during sit-to-stand (SitTS) task. Methods: Nineteen healthy females participated in this study. The subjects performed the SitTS task wearing high-heeled shoes and barefoot. The experiment was repeated three times for each task with foot conditions. The kinematics and kinetics of the knee joint were measured and analyzed using a 3D motion analysis system. Results: The result of this study showed kinematic and kinetics differences in knee joints during the SitTS task based on high-heeled shoes. Significant differences in knee flexion angle were observed during SitTS. The knee extensor force showed statistically significant differences during SitTS tasks. At the initial of SitTS, the knee flexor and extensor moment showed significant differences. The knee extensor moment showed statistically significant differences at the terminal of SitTS. At the maximum of SitTS, the knee extensor moment showed statistically significant differences. Conclusion: Therefore, wearing high-heeled shoes during SitTS movements in daily life is considered to influence knee joint kinematics and kinetics due to the HH, suggesting the possibility of increased risk of patellofemoral pain, and knee osteoarthritis caused by changes in loading of the knee joint.

• Physical Therapy Korea
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• v.26 no.1
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• pp.60-66
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• 2019

Background: Knee osteoarthritis (OA) is a single most arthritic disease. Knee joint space width (JSW) is commonly used for grading severity of knee OA. However, previous studies did not established criterion validity and test-retest reliability of ultrasound (US) image for measuring JSW. Objects: The aim of this study was to establish criterion validity and test-retest reliability of US measurement of medial and lateral knee JSW. Methods: Twenty-nine subjects with knee OA were participated. The US and X-ray were used to measure knee JSW. One sample Kolmogorov-Smirnov test was used to confirm the data normal distribution. Pearson correlation coefficient and ICC were used to calculated and establish criterion validity and test-retest reliability, respectively. Results: US measurement of medial and lateral knee JSW was highly correlated with radiographic imaging measure (r=.714 and .704, respectively). Test-retest reliabilities of medial and lateral knee JSW were excellent correlated (ICC=.959 for medial side and .988 for lateral side, respectively). Conclusion: US may be valid tool to measure knee JSW.

• Korean Journal of Applied Biomechanics
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• v.24 no.1
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• pp.27-33
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• 2014

In volleyball, the most common injuries are anterior cruciate ligament (ACL) tears. For this reason, volleyball players frequently use knee brace as prophylactic and rehabilitation measures. The purpose of the study was to investigate the effects of knee brace on anterior cruciate ligament injuries risk factors during spike take off in female volleyball players. Fifteen female volleyball players were recruited and performed randomly spike take off with and without knee brace. Kinematics and ground reaction data were collected to estimate the anterior cruciate ligament injuries risk factors. The ACL risk factors are knee maximum flexion angle, thigh maximum adduction angle, thigh maximum internal rotation angle, shank maximum abduction angle, shank maximum external rotation angle, knee maximum extension moment and knee maximum abduction moment. Data were analyzed with paired samples t-test with Bonfferoni collection. Female volleyball players with knee brace had no significant results in knee maximum flexion angle, thigh maximum adduction angle, thigh maximum internal rotation angle, shank maximum abduction angle and shank maximum external rotation angle compare to without knee brace. Female volleyball players, however, with knee brace showed more reduced knee maximum extension moment and knee maximal abduction moment than without knee brace. In conclusion, Female volleyball players with knee brace reduced anterior cruciate ligament stress.

• The Journal of Korean Physical Therapy
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• v.15 no.3
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• pp.166-172
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• 2003

The aim of this study is to present the basic reference data of age and specific gait parameters for comparisons of the gait characteristics depended on amputation length of the Unilateral Trans-Tibial Prostheses. The basic gait parameters were extracted from 10 Adult, and 20 below knee(B/K) patients, 50 to 60 years of age using VICON 512 Motion Analyzer. The results were as follows; 1. The mean Cadence of the above knee(A/K) patients and below knee(B/K) patients were $87.77{\pm}8.64$ steps/min, to $99.84{\pm}11.14$ steps/min.(p<0.05) 2. The mean Walking Speed of the above knee(A/K) patients and below knee(B/K) patients were $0.84{\pm}0.15$ m/s, to $0.96{\pm}0.25$ m/s.(p>0.05) 3. The mean Stride Length of the above knee(A/K) patients and below knee(B/K) patients were $1.14{\pm}0.14\;m$, to $1.14{\pm}0.22m$.(p>0.05) 4. The mean maximal angles of joint on the hip flexion motion for different above knee(A/K) patients and below knee(B/K) patients were $34.75{\pm}10.18_{\circ}$, to $32.32{\pm}6.34_{\circ}$.(p>0.05) 5. The mean maximal angles of joint on the knee flexion motion for different above knee(A/K) patients and below knee(B/K) patients were $66.97{\pm}15.08_{\circ}$, to $52.65{\pm}9.21_{\circ}$. (p<0.05) 6. The mean maximal angles of joint on the ankle dorsi-flexion motion for different above knee(A/K) patients and below knee(B/K) patients were $14.41{\pm}4.82_{\circ}$, to $10.04{\pm}3.49_{\circ}$.(p>0.05) 7. The mean maximal angles of joint on the ankle plantar-flexion motion for different above knee(A/K) patients and below knee(B/K) patients were $5.77{\pm}3.17_{\circ}$, to $2.75{\pm}4.49_{\circ}$.(p>0.05)

• Physical Therapy Korea
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• v.12 no.1
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• pp.45-54
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• 2005

The quadriceps-angle (Q-angle) and the ratio of hamstring/quadriceps (H/Q) are important for the stability of the knee and for protection from excessive stress. The aim of this study was to examine the association between Q-angle and H/Q ratio with and without knee osteoarthritis. We compared knee osteoarthritis patients with symptom-free women. The mean age of the patients in the arthritis group (25 women, osteoarthritis) was 59.7 years. The non-arthritis group consisted of 25 women with a mean age of 55.2 years. Of the 25 women with osteoarthritis, 5 had the condition in their left knee, 5 had it in their right knee, and 15 had it on both sides. There was no significant difference in the knee Q-angle of the left and right knees of the arthritis group and the non-arthritis-group (p>.05). The strength of all the muscles around the involved right knee in the arthritis group was significantly weaker than that of the non-arthritis group (p<.05). However, in the left knee, only the strength of the knee extensors and internal rotators was significantly weaker than that of the non-arthritis group (p<.05). The Q-angle was not associated with the H/Q ratio and internal rotators/external rotators ratio of the involved knee in the arthritis group (p>.05). Neither was the Q-angle associated with the pain level of an involved knee in the arthritis group (p>.05). The knee pain was not associated with the H/Q ratio of the involved knee in the arthritis group (p>.05). The Q-angle was not associated with the ratio of H/Q and pain level of the involved knee in the osteoarthritis women.

• Steel and Composite Structures
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• v.13 no.1
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• pp.1-13
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• 2012

In this study, a new structural bracing system named 'Hat Knee Bracing' (HKB) is presented. In this structural system, a special form of diagonal braces, which is connected to the knee elements instead of beam-column joints, is investigated. The diagonal elements provide lateral stiffness during moderate earthquakes. However the knee elements, which is a fuse-like component, is designed to have one plastic joint in the knee elements for dissipation of the energy caused by strong earthquake. First, a suitable shape for brace and knee elements is proposed through elastic studying of the system and several practical parameters are established. Afterward, by developing applicable and highly accurate models in Drain-2DX, the inelastic behavior of the system is carefully considered. In addition, with inelastic study of the new bracing system and comparison with the prevalent Knee Bracing Frame system (KBF model) in nonlinear static and dynamic analysis, the seismic behavior of the new bracing system is reasonably evaluated.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.4
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• pp.715-720
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• 2011

We performed this study to assess pain in patients with knee osteoarthritis. Participants were 120 Patients(men 26 and women 94) with knee osteoarthritis. Pain evaluations were conducted using survey composed of 12 items by interview with oriental medicine doctor. Collected data were analyzed by IBM SPSS Statistics 19.0. Women were 3.8 times more than men(21.7% vs 78.3%). Approximately 80% of participants were overweight and obesity. Descending stair is most painful action for knee osteoarthritis patients. The average degree of knee pain was more than moderate. 5. People diagnosed as arthritis before had the much higher knee pain than never diagnosed before. This study showed female gender, overweight and obesity were associated with the risk of knee arthritis and participants complained knee pain more than moderate. It is hoped that our findings provide information that help the treatment of knee osteoarthritis.

• PNF and Movement
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• v.11 no.2
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• pp.111-117
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• 2013

Purpose : The purpose of this study was to examine the activity of the knee flexor and extensor with ankle plantar flexion and dorsiflexion. Methods : A total of 18 subjects(Male 6, female 12) performed 4 lower extremity patterns of PNF and the activities of the vastus medialis oblique, rectus femoris, vastus lateralis, biceps femoris, semitendinosus ipsilateral sides were measured using electromyography. Results : During 4 lower extremity patterns of PNF, knee flexor and extensor muscle activity were significantly difference. Knee extensors were shown to be higher knee extension and ankle dorsiflexion combined pattern. Knee flexors were shown to be higher knee flexion and ankle plantarflexion combined pattern. Conclusion : We suggest that it is efficient to strengthening of knee extensors with ankle dorsiflexion and to strengthening of knee flexors with ankle plantar flexion. Also, for the functioning as toe standing, we have to choice appropriate movement pattern.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.6_1
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• pp.917-925
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• 2022

The purpose of this study was to investigate the effect of wearing a soft knee brace during balance training on paretic side foot pressure and knee joint muscle strength in stroke patients. The recruited 20 stroke patients were randomized into 10 experimental group and 10 control group. All subjects were subjected to balance training, and only the experimental group was trained in balance while wearing a soft knee brace. Experimental group and the control group before and after the intervention showed significant increases in foot pressure and knee joint muscle strength on the paralyzed side (p<0.05), experimental group showed a significant increase in foot pressure and knee joint muscle strength compared to the control group (p<0.05). This study confirmed that wearing a soft knee brace had a positive effect on paretic side foot pressure and knee joint muscle strength in stroke patients.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.2
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• pp.165-171
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• 2016

A prosthetic knee for above-knee (AK) amputee is categorized into passive and active type. The passive prosthetic knee is generally made by elastic material. Although AK amputee can easily walk by using passive prosthetic leg, knee joint motions are not similar to ordinary persons. The active prosthetic leg can control the knee angle owing to the actuator and microprocessor. However, the active type is not cost-effective and the stability may be lost due to the malfunction of sensors. In order to resolve these disadvantages of passive and active type, a semi-active prosthetic knee which can control the knee angle is proposed in this work. The proposed semi-active one requires a less input energy but provides active type performance. In order to achieve this goal, in this work, a semi-active prosthetic knee using magneto-rheological (MR) damper for AK amputees is designed. The MR damper can support the weight of body by using less energy than actuator of active prosthetic. It can control knee angle by inducing the magnetic field at the time of stance phase. This salient characteristic is evaluated and presented in this work.