• International Journal of Precision Engineering and Manufacturing
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• v.9 no.1
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• pp.30-33
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• 2008

Understanding the characteristics of amputee gait is key in developing more advanced prostheses. The aim of this study was to quantitatively analyze a stair-climbing task for transfemoral amputees with a prosthesis and to predict the muscle forces and joint moments at musculoskeletal joints using a dynamic analysis. A three-dimensional musculoskeletal model of the lower extremities was constructed from a gait analysis using transformation software for two transfemoral amputees and ten healthy people. The measured ground reaction forces and kinematical data of each joint from the gait analysis were used as input data for an inverse dynamic analysis. Dynamic analyses of an transfemoral amputee climbing stairs were performed using musculoskeletal models. The results showed that the summed muscle forces of the hip extensor of an amputated leg were greater than those of a sound leg. The opposite was true at the hip abductor and knee flexor of an amputated leg. We also found that higher moments at the hip and knee joints of the sound leg were required to overcome the flexion moment caused by the body weight and amputated leg. Dynamic analyses using musculoskeletal models may be a useful means to predict muscle forces and joint moments for specific motion tasks related to rehabilitation therapy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.276-282
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• 2016

This study examined the effects of 8-weeks hip muscle training on the hip joint abductor muscle isokinetic strength and foot pressure distribution in elite players with chronic ankle instability (N=19). A total of 19 subjects had chronic ankle instability from at least 2 ankle sprains, and were given 8-weeks hip muscle training exercise. The hip muscle strength of the elite players with chronic ankle instability increased significantly, but the foot pressure distribution and ratio of the foot pressure distribution of the elite players with chronic ankle instability did not reach statistical significance and the ratio of the foot pressure distribution showed a similar trend. These results suggest that the strength and foot pressure distribution of the affected-side might increase to that of the unaffected-side. The 8-weeks hip muscle training helped improve the chronic ankle instability of the elite players. Therefore, the hip muscle strength and foot pressure distribution are the primary factors of a rehabilitation program on ankle sprains.

• Physical Therapy Korea
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• v.31 no.2
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• pp.123-130
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• 2024

Background: Weakness of gluteus medius (Gmed) is related with musculoskeletal disorders. Individuals who experience weakness in the Gmed may activate the tensor fasciae latae (TFL) as a compensatory mechanism. Application of isometric hip extension (IHE) with Thera-band may affect the activities of the Gmed, gluteus maximus (Gmax), and TFL, and the activity ratio of Gmed/TFL during side-lying hip abduction (SHA). Objects: To determine the influences of IHE during SHA on Gmed, Gmax, and TFL activities in participants with Gmed weakness. Methods: Three types of SHA exercises were performed: 1) traditional SHA in the frontal plane (SHA-T), 2) SHA with IHE applying Thera-band in the frontal plane (SHA-IHE), 3) and SHA with isometric hip flexion (IHF) applying Thera-band in the frontal plane (SHA-IHF). Results: SHA-IHE significantly showed higher Gmed and Gmax activities than SHA-T and SHA-IHF. SHA-IHF significantly showed higher activity of TFL than SHA-T or SHA-IHE. The activity ratio of Gmed/TFL was significantly higher in the SHA-IHE, SHA-T, and SHA-IHF, in that order. Conclusion: The SHA-IHE resulted in higher activities of Gmed, Gmax and a higher muscle ratio of Gmed/TFL.

• Korean Journal of Applied Biomechanics
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• v.20 no.1
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• pp.75-81
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• 2010

Knee osteoarthritis is one of the most prevalent arthritis that weakens the muscles. This study focused on evaluating muscular functionality of knee osteoarthritis subjects. Muscular strengths of muscles around knee and hip joints of middle-aged female subjects aged over 40 suffering from knee osteoarthritis were evaluated by isokinetic dynanometer. Also, relation between the observed muscle imbalance in knee and hip joints and visual analogue scale was investigated. Subjects performed 8-weeks exercise on weakened muscles - particularly on knee extensors and hip abductors - and had their isokinetic muscular functionalities analyzed again. After the 8-weeks exercise, subjects' thigh circumferences were increased, accompanied with muscular strength improvements and decrease in visual analogue scale. Hence we emphasize the importance of exercise for muscular strength enhancement of knee extensors and hip abductors, in rehabilitation programs for knee osteoarthritis.

• The Korean Journal of Pain
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• v.8 no.1
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• pp.149-151
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• 1995

Piriformis syndrome is a syndrome of low back and leg radiating pain thought to be due to a chronic contracture of the piriformis muscle that causes irritation of the sciatic nerve. The piriformis muscle is a flat pyramidal muscle, an external rotator and abductor of the hip, originating from the front of the sacrum and inner aspect of the sacroiliac joint, then passes laterally out of the sciatic notch to attach posteriorly to the greater trochanter of the femur, the sciatic nerve passes between the two bellies of the muscle. Mechanical irritation of the sciatic nerve by an inflammatory reaction of the piriformis muscle and its fascia at this pelvic level causes pain to radiate in the dermatomal regions of the nerve roots similar to that disk entrapment. diagnosis of piriformis syndrome is made primary on the basis of history and clinical examination. The incidence is considerably higher in women, with the reported ratio of women to men of 6:1. These patients frequently present with associated symptoms of pelvic pain and/or dyspareunia. Symptoms are usually unilateral but occasionally be bilateral. We had a 42 year-old woman patient with low back and left leg radiating pain and dyspareunia treated by caudal steroid and local anesthetic.

• Journal of The Korean Society of Integrative Medicine
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• v.3 no.2
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• pp.47-54
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• 2015

Purpose: This study was to investigate the effects of lumbar stabilization exercise and lower extremity strengthening program on pain, lower extremity muscle in patients with chronic low back pain. Method: The subject were randomly divided two groups. 15 people who were conducted lower extremity exercises and lumbar stabilization exercises called the combined exercise group and other(15 people) who were only conducted lower extremity exercise group. The assessment tools were the pain level and the led muscle power. Exercise was conducted for eight weeks. Result: Pain of the combined exercise group showed significant differences in the change in pain level(p<.05). The leg muscle power showed significant differences within group which hip flexor, extensor muscles and abductor muscles. there were significant differences within combined exercise group (p<.05). But the knee joint in each group showed a significant difference within group (p<.05). Conclusion: This study suggest that the lumbar stabilization exercises and lower extremity exercises showed more efficient results in the pain levels and leg muscles power than only the lower extremity exercise for patients with lumbar instability.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.4
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• pp.127-137
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• 2016

PURPOSE: This study aimed to compare the effects of side-lying hip abduction exercise with and without vibration on pain, disability, strength and balance in individuals with low back pain. METHODS: 30 participants enrolled in this study were randomly assigned to an experimental group (EG, n=15) for side-lying hip abduction with vibration and a control group (CG, n=15) for side-lying hip abduction without vibration. Both groups were treated 3 times per week for 4 weeks. Pain (Numeric Rating Scale), disability (Korean Oswestry Disability Index), hip abductor muscle strength, and static balance were measured in both groups before and after the program. Results were analyzed using paired t-test for comparing the difference within the group and independent t-test for comparing the difference between two groups. RESULTS: Compared to the CG, the EG showed significantly greater reductions in pain and disability (p<.05). There was a significant difference in all balance categories of both the painful and non-painful sides within the EG (p<.05). Balance showed a significant decrease except the envelope area (ENV) on the non-painful side within the CG (p<.05). There was a significant increase in all balance categories except ENV of non-painful side between the two groups (p<.05). Balance increased on both the painful and non-painful sides in the EG. Balance improved on the painful side in the CG, but significantly decreased on the non-painful side (p<.05). CONCLUSION: Side-lying hip abduction exercise with vibration is considered an effective treatment for pain, disability and balance in individuals with low back pain.

• Physical Therapy Korea
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• v.30 no.3
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• pp.194-201
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• 2023

Background: Falls are a common and serious problem in the elderly population. Muscle strength and balance are important factors in the prevention of falls. The Y-balance test (YBT) is used to assess dynamic postural control and shows excellent test-retest reliability. However, no studies have examined the relationship between lower-limb strength and YBT scores in elderly women. Objects: This study aimed to examine the relationship between lower-limb strength and YBT scores in elderly women. Methods: Thirty community-dwelling elderly women participated in the study. Lower-limb strength including hip flexor, hip extensor, hip abductor (HAB), hip adductor (HAD), knee flexor, knee extensor, ankle dorsiflexor, and ankle plantar flexor (PF) muscles was examined using a smart KEMA strength sensor (KOREATECH Inc.), and the YBT was used to assess dynamic balance. Relationship between lower-limb strength and YBT was demonstrated using a Pearson's correlation coefficient. Results: HAB strength (r = 0.388, p < 0.05), HAD strength (r = 0.362, p < 0.05), and ankle PF strength (r = 0.391, p < 0.05) positively correlated with the YBT-anterior direction distance. Ankle PF strength was positively correlated with the YBT-posteromedial direction distance (r = 0.396, p < 0.05) and composite score (r = 0.376, p < 0.05). Conclusion: The results of this study suggest that HAB, HAD, and ankle PF strengths should be considered for dynamic postural control in elderly women.

• PNF and Movement
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• v.17 no.1
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• pp.93-101
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• 2019

Purpose: This study aimed to investigate lower extremity muscle activation to the variable weight shift on the affected side of patients with hemiplegia. Methods: Eighteen patients with chronic hemiplegia volunteered to participate in this study. All participants performed three types of weight shift (sideways, forward, and backward) in limits of stability on the affected side. Muscle activation in a paralyzed leg was measured with electromyography on the gluteus medius, tensor fasciae latae, rectus femoris, and biceps femoris; furthermore, the attached area was recommended by SENIAM projects. Each weight shift was performed three times, and then the mean value of the three measurements was analyzed. The data were analyzed by measuring the symmetrically standing position with the reference voluntary contraction (RVC) and was standardized with the percentage of RVC method. Results: No significant difference in lower extremity muscle activation occurred according to the three types of variable weight shift. However, significant differences in lower extremity muscle activation did occur with each weight shift position. In addition, activation increased at the rectus femoris and decreased at the gluteus medius and tensor fasciae latae. Conclusion: Hip abductor muscle strength training and variable weight shifts on the affected side must increase to improve patients'balance and limits of stability.

• Hip & pelvis
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• v.35 no.2
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• pp.99-107
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• 2023

Purpose: Bipolar hemiarthroplasty has recently been acknowledged as an effective option for treatment of unstable intertrochanteric fracture. Trochanteric fragment nonunion can cause postoperative weakness of the abductor muscle and dislocation; therefore, reduction and fixation of the fragment is essential. The purpose of this study was to perform an evaluation and analysis of the outcomes of bipolar hemiarthroplasty using a useful wiring technique for management of unstable intertrochanteric fractures. Materials and Methods: A total of 217 patients who underwent bipolar hemiarthroplasty using a cementless stem and a wiring technique for management of unstable intertrochanteric femoral fractures (AO/OTA classification 31-A2) at our hospital from January 2017 to December 2020 were included in this study. Evaluation of clinical outcomes was performed using the Harris hip score (HHS) and the ambulatory capacity reported by patients was classified according to Koval stage at six months postoperatively. Evaluation of radiologic outcomes for subsidence, breakage of wiring, and loosening was also performed using plain radiographs at six months postoperatively. Results: Among 217 patients, five patients died during the follow-up period as a result of problems unrelated to the operation. The mean HHS was 75±12 and the mean Koval category before the injury was 2.5±1.8. A broken wire was detected around the greater trochanter and lesser trochanter in 25 patients (11.5%). The mean distance of stem subsidence was 2.2±1.7 mm. Conclusion: Our wiring fixation technique can be regarded as an effective additional surgical option for fixation of trochanteric fracture fragments during performance of bipolar hemiarthroplasty.