• 제목/요약/키워드: Weight-bearing

검색결과 994건 처리시간 0.028초

인공발목관절의 표면 마모 특성 (Surface Tribology of Total Ankle Joint Replacement)

  • Jeong, Yong-Hoon;Jung, Tae-Gon;Yang, Jae-Woong;Park, Kwang-Min;Lee, Su-Won
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2016년도 추계학술대회 논문집
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    • pp.117-117
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    • 2016
  • Total ankle replacement (TAR) is a visible option in the surgical treatment of degenerative or inflammatory diseases of ankle joint. it is attributed to the current TAR which has improvements in surgical technique, uncemented implant fixation and minimally constrained articulation. In the clinical result, they can show promised surgical result when compared to earlier attempts in TAR. However, TAR is still not as successful as total knee replacement (TKR) or total hip replacement (THR), it needs to be note that there are limitations in concerning of long term performance of TAR, the high failure rate still associated with wear of the PE (polyethylene) component that has related with their material property and surface roughness. The aim of this study was to introduce the tribology characteristics of total ankle joint prosthesis with one of TDR model which was fabricated to try multi-axis wear test as a region of motion in ankle joint. The wear specimen of TDR was prepared with Ti-6Al-4V alloy and UHMWPE (ultra-high molecular weight polyethylene) for tibia-talus and bearing component, respectively. A wear test was carried out using a Force 5 (AMTI, Massachusetts, US) wear simulator which can be allowed to move in three axis to flexion-extension ($+3^{\circ}{\sim}-6^{\circ}$), internal-external axial rotation (${\pm}5^{\circ}$), as well as sinusoidal compressive load (1.6 kN, R=10). All tests were performed following standard ISO 14243, wear rate was calculated with weight loss of UHMWPE bearing while the specimen has tested at certain cycles. As based on the preliminary results, wear rate of UHMWPE bearing was $7.9{\times}10^{-6}mg/cycles$ ($R^2=0.86$), calculated loss weight until $10^7cycles$ was 79 mg, respectively.

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트레드밀 훈련이 경직성 양하지 마비 아동의 대동작 운동 기능에 미치는 영향 (The Effects of Treadmill Training on Spastic Cerebral Palsy Children's Gross Motor Functions)

  • 최현진;김윤환
    • 대한물리치료과학회지
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    • 제19권3호
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    • pp.23-30
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    • 2012
  • The purpose of this study was to apply treadmill training through motor learning to cerebral palsy children and examine its effects on their Gross Motor Functions. The subjects of this study were 13 spastic diplegia children who had difficulty in independent gait, and GMFCS level III, IV. We performed treadmill gait training using the principle of weight bearing, based on 4times a week for 30 minutes before and after each session physical therapy we gave weight bearing treadmill training 5 to 10 minutes, during 7 weeks(April 9, 2012~May 26, 2012) fittingly for the children's gait characteristics. In order to test how the weight bearing treadmill training affects spastic diplegia children's gross motor functions, we measured body mobility with Gross Motor Function Measure (GMFM). These data were collected before and after the experiment and analyzed through comparison. Data collected from the 13 spastic diplegia children the results were as follows. For evaluating with regard to change in body mobility, significant difference was observed between before and after the experiment in measured gross motor functions, which were crawling, kneeling, standing, walking, jumping and running(p<0.05). According to the results of this study, when gait training through motor learning was applied to spastic cerebral palsy children, it made significant changes in their body mobility. Accordingly, for the effective application of gait training through motor learning to cerebral palsy children, it is considered necessary to make research from different angle on how such training affects children's mobility, activity of muscles in the lower limbs, and gait characteristics.

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Bilateral Patellar Groove Replacement in a Dog with Iatrogenic Trochlear Groove Damage

  • Kim, Yongrak;Park, Yunsik;Park, Jiyoung;Jeong, Seong Mok;Lee, Haebeom
    • 한국임상수의학회지
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    • 제33권5호
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    • pp.295-299
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    • 2016
  • A 2-year-old, 1.94 kg spayed female Toy Poodle was referred for revision surgery for patellar reluxation following surgery for bilateral medial patellar luxation (MPL). Intermittent non-weight-bearing lameness of the right hindlimb and weight-bearing lameness of the left hindlimb were evident on general inspection. A physical examination revealed that there was a bilateral grade 4 MPL. On radiographs, the medial and lateral trochlear ridge was bilaterally worn out. Patellar groove replacement (PGR) was performed in two stages to replace the bilateral femoral trochlea that had a severely worn out groove. Corrective femoral osteotomy with increasing anteversion angle, tibial tuberosity transposition, medial releasing, lateral imbrications and PGR were performed on the right hindlimb. Six months after surgery on the right hindlimb, a PGR prosthesis was positioned medially on the frontal plane and tibial tuberosity transposition and lateral imbrications were performed on the left hindlimb. Two weeks after surgery, reluxation of the patella occurred on the left hindlimb. The tibial tuberosity transposition was performed to realign the patella more laterally than the previous surgery, and a patellar sling was applied. Two years after the last surgery, the patient showed no pain on the stifle joint and satisfactory weight-bearing ambulation. Reluxation did not recur. PGR maybe a successful treatment for dogs with iatrogenically damaged and/or worn out patellar grooves.

아킬레스건 파열 이후의 능동적인 관절 범위 운동이 없는 간단한 재활 운동 방법 (Simple Postoperative Exercise of Acute Achilles Tendon Rupture without Active Range of Motion Exercise)

  • 황재광;정영주;서동교
    • 대한족부족관절학회지
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    • 제27권1호
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    • pp.12-16
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    • 2023
  • Purpose: Postoperative exercise for acute Achilles tendon rupture is important for a patient's return to daily life and sports. On the other hand, the protocol requires considerable effort to educate patients and continuous checking. This study evaluated the outcome of a new simple and delayed rehabilitation protocol after Achilles tendon rupture repair. Materials and Methods: From July 2014 to November 2020, one hundred eighty-three patients were operated on by one surgeon. The exercise protocol was classified into two methods. One group (immediate protocol, control group) started immediate full weight bearing with a 20° plantar flexion range of motion from two days postoperatively. Ankle dorsiflexion was restricted to 0°. The other group (delayed protocol, case group) started full weight bearing with a controlled ankle motion boot from two weeks postoperatively. No range of motion exercise was allowed until six weeks postoperatively. Age, sex, body mass index, ankle range of motion, muscle power, time to return to previous physical activity, functional score, and complication rate were evaluated. The results of the two groups were compared using a Mann-Whitney test. Statistical significance was set as p<0.05. Results: The range of motion, double heel rising, and one-leg standing were achieved faster in the control group (p<0.05). However, single-heel rising, repeated single-heel rising, return to previous activity (work, run, and sport), and functional scores showed no statistical difference (p>0.05). Conclusion: Simple and delayed postoperative rehabilitation of acute Achilles tendon rupture without active range of motion exercises showed satisfactory functional results and a low complication rate.

Numerical study of strength reduction-induced capillary rise effect for unsaturated soil

  • Shwan, Bestun J.
    • Geomechanics and Engineering
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    • 제31권4호
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    • pp.385-393
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    • 2022
  • Previous studies postulated insignificant capillary rise (hc) effect above the water table (Hw) for unsaturated soils. In addition, these studies utilised dry unit weight above Hw. This paper, therefore, addresses the effect of these postulations on strength where the influence of hc using a modified upper bound approach, Discontinuity Layout Optimization (UNSAT-DLO) for a simulated soil was predicted. Two different parametric studies to model passive earth pressure and bearing capacity problems are carried out to provide an insight into the effect of capillary rise on strength. Significant increase in strength, owing to unsaturated conditions, was obtained where the maximum increase was when suction slightly less or greater than the air entry suction. On the other hand, the results showed a negative effect of hc. For example, up to 8.24% decrease in passive thrust (Pp) was obtained at Hw=0 m when hc rose 1 m from 0 m. To put this into perspective, this was equivalent to a decrease of about 2° in 𝜙 at Hw=0 m and hc =0 m in order to obtain the same result at hc =1 m. For the bearing capacity problem, the effect was seen to be higher, up to 18.4% decrease in N𝛾 was obtained when hc rose from 0 m to 2.5 m at Hw =0 m. In addition, the results revealed a negative influence of assigning dry unit weight above Hw or hc.. However, considerable increase in strength was obtained when unsaturated unit weight above hc was assigned.

Effects of Visual Feedback Short Foot Exercise on Foot Pressure in Adults with Flexible Flat Foot

  • Jeong, Dawoon
    • 국제물리치료학회지
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    • 제10권4호
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    • pp.1934-1939
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    • 2019
  • Background: Flexible flat foot is that the medial longitudinal arch collapses in weight bearing and returns normal arch when weight is removed and the weight bearing shifts toward medial part of the foot, which can cause pathological problems in the alignment of the lower extremities and the entire body. Objective: To compare the foot pressure for adults with flexible flat foot. Design: Quasi-Experimental Study Methods: 24 participants with flexible flat foot were recruited and were randomly divided into Visual feedback Short Foot Exercise (VSFE) group and Short Foot Exercise (SFE) group. To compare changes of foot pressure about pre and post intervention, the contact pressure measurement was conducted. Results: In the VSFE, significant differences were observed for the foot pressure of the 1st toe, 1st, 3rd and 4-5th metatarsal, midfoot, medial and lateral heel (p<.05). The foot pressure of the 3rd and 4-5th metatarsal, midfoot showed significant differences in the SFE (p<.05). The contact pressure of the 1st toe, 3rd metatarsal showed significant differences between the groups. Conclusions: Visual feedback short foot exercise can be useful for moving the pressure from medial to lateral part, and can prevent possible pathological problems.

Free Flap Reconstruction in Patients with Traumatic Injury of the Forefoot

  • Kang, Shin Hyuk;Oh, Jeongseok;Eun, Seok Chan
    • Journal of Trauma and Injury
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    • 제32권3호
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    • pp.187-193
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    • 2019
  • Many techniques have been developed for reconstruction of the hand; however, less attention has been paid to foot reconstruction techniques. In particular, reconstruction of the forefoot and big toe has been considered a minor procedure despite the importance of these body parts for standing and walking. Most of the weight load on the foot is concentrated on the forefoot and big toe, whereas the other toes have a minor role in weight bearing. Moreover, the forefoot and big toe are important for maintaining balance and supporting the body when changing directions. Recently, attention has been focused on the aesthetic appearance and functional aspects of the body, which are important considerations in the field of reconstructive surgery. In patients for whom flap reconstruction in the forefoot and big toe is planned, clinicians should pay close attention to flap survival as well as functional and cosmetic outcomes of surgery. In particular, it is important to assess the ability of the flap to withstand functional weight bearing and maintain sufficient durability under shearing force. Recovery of protective sensation in the forefoot area can reduce the risk of flap loss and promote rapid rehabilitation and functional recovery. Here, we report our experience with two cases of successful reconstruction of the forefoot and big toe with a sensate anterolateral thigh flap, with a review of the relevant literature.

Anticancer and Radiosensitization Efficacy of Nanocomposite Withania somnifera Extract in Mice Bearing Tumor Cells

  • Abdallah, Nadia M;Noaman, Eman;Eltahawy, Noaman A;Badawi, Abdelfattah M;Kandil, Eman;Mansour, NA;Mohamed, Hebatallah E
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권9호
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    • pp.4367-4375
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    • 2016
  • The objective of the present study was to evaluate the anticancer and radio-sensitizing efficacy of a Withania somnifera extract/Gadolinium III oxide nanocomposite (WSGNC) in mice. WSGNC was injected to solid Ehrlich carcinoma-bearing mice via i.p. (227 mg/kg body weight) 3 times/week during 3 weeks. Irradiation was performed by whole body fractionated exposure to 6Gy, applied in 3 doses of 2 Gy/week over 3 weeks. Biochemical analyses as well as DNA fragmentation were performed. Treatment of solid Ehrlich carcinoma bearing mice with WSGNC combined with ${\gamma}$-radiation led to a significant decrease in the tumor size and weight associated with a significant decrease in mitochondrial enzyme activities, GSH content and SOD activity as well as a significant increase in caspase-3 activity, MDA concentration and DNA fragmentation in cancer tissues. Combined treatment of WSGNC and low dose of ${\gamma}$-radiation showed great amelioration in lipid peroxidation and antioxidant status (GSH content and SOD activity) in liver tissues in animals bearing tumors. It is concluded that WSGNC can be considered as a radio-sensitizer and anticancer modulator, suggesting a possible role in reducing the radiation exposure dose during radiotherapy.

편마비 환자의 보행훈련 시 기능적 전기자극 병용이 척수신경원의 흥분성 변화에 미치는 효과 (The Effect on Change of Spinal Neuron Excitability during Gait Training of Hemiplegia Patients by the Functional Electrical Stimulation)

  • 강양훈;윤세원;서삼기;박경순;김용억;김태열
    • The Journal of Korean Physical Therapy
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    • 제19권1호
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    • pp.11-22
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    • 2007
  • Purpose: The purpose of this study were to analysis the effect on change of spinal neuron excitability during gait training of hemiplegia patients by the functional electrical stimulation. Methods: Thirty six hemiplegia patients participated in this study. Stimulation conditions of FES were pulse rate 35pps, pulse width $250{\mu}s$, and on-time 0.3 second, treatment hour was 30 min. and treatment period was once a day for five days a week through six weeks. For functional evaluations before and after treatment, Modified Ashworth Scale (MAS), active range of motion (AROM), Hmax threshold, H/Mmax ratio were measured and the following conclusions were obtained. Results: Functional evaluation showed significant changes in experimental group as MAS(p<0.01), AROM(p<0.001), compared to control group. In spinal neuron excitability evaluation, change of Hmax threshold was significantly reduced in both non weight bearing (p<0.001) and bearing condition (p<0.05), H/Mmax ratio was significantly reduced in non weight bearing (p<0.05) and bearing condition (p<0.05). Conclusion: In conclusion, application of FES to hemiplegia patients in recovery stage during gait training improved mitigation of muscular spasticity, balance adjustment and moving ability and it was interpreted that it was caused by mitigation of muscular spasticity by the spinal neuron excitability.

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금령(金嶺) 및 기구광상(基邱鑛床)의 동광화작용(銅鑛化作用) (The Copper Mineralization of the Keumryeong and Kigu Ore Deposits)

  • 박희인;설용구
    • 자원환경지질
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    • 제25권3호
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    • pp.283-296
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    • 1992
  • The Keumryeong deposits is a low grade copper deposits in which copper minerals form disseminated grains and thin veinlets in felsic volcanics seem to be dacite. Alteration of the volcanics consists mainly pervasive propylitization and silicification. Potassic alteration characterized by biotite developed locally adjacent to southwestern contact of granodiorite body. Principal sulfide minerals in altered zone are mainly pyrite and lesser chalcopyrite. Chalcopyrite content in potassic zone is relatively higher than that of surrounding propylitized zone. Pyrite and chalcopyrite accompanies magnetite, molybdenite, sphalerite, pyrrhotite, arsenopyrite, pentlandite, marcasite, hematite, ilmenite, rutile, bismuthinite and native Bi as disseminations, veinlets and knots. Granodiorite body is propylitized and contains veinlets of pyrite, chalcopyrite and molybdenite. Fluid inclusions in sulfide-bearing quartz veinlets and quartz grains of felsic volcanics and granodiorite in altered zone consist of liquid-rich, vapor-rich, $CO_2-bearing$ and halite-bearing inclusions. These four types of inclusion intimately associated on a microscopic scale and indicate condensing or boiling of ore fluid during mineralization. Homogenization temperature of coexisting fluid inclusions are mostly in the range of 350 to $450^{\circ}C$. High salinity fluid contains 28.6 to 48.4 weight percent NaCI equivalent and moderate salinity fluid cotains 0.5 to 12.5 weight percent NaCl equivalent. Pressure estimated from $CO_2$ mole fraction of $CO_2-bearing$ inclusion range 160 to 375 bars. The Kigu copper deposits is a fissure filling copper vein developed 500 m south from the Keumryong deposits. Mineralogy and fluid inclusion data of the Kigu deposits are similar to that of the Keumryeong deposits. Homogenization temperature of fluid inclusions from the Kigu deposits are reasonable agreement with temperature estimated from sulfidation curve of cubanite-chalcopyrite-pyrite-pyrrhotite and pyrite-pyrrhotite mineral assemblages. Not only mineral occurrence and wall rock alteration in the Keumryeong deposits but also fluid inclusion data such as temperature, salinity, pressure and boiling evidences are similar to those of porphyry copper deposits.

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