• 한국운동역학회지
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• 제24권2호
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• pp.95-101
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• 2014

The purpose of this study was to investigate the training and detraining effects of a 8-week water exercise on lower extremities coordination during obstacle gait in the female elderly. Eight elderly participants (age: $76.58{\pm}4.97$ yrs, height: $148.88{\pm}7.19$ cm, body mass: $56.62{\pm}6.82$ kg, and leg length: $82.36{\pm}2.98$ cm), who stayed at the Seoul K welfare center, were recruited for this study. All participants had no history of orthopedic abnormality within the past 1 year and completed the aquatic exercise program which lasted for 8 weeks. To identify the training and detraining effect of 8 weeks of water exercise, a 3-D motion analysis with 7 infrared cameras and one force plate sampling frequency set at 100 Hz and 1,000 Hz, respectively, was performed. A two-way ANOVA was performed to find training and detraining effects among diferent obstacle heights. In this study significant level was set at .05. Significant training effects of LTS (lead foot thigh and shank) coordination in all obstacle height were found (p<.05). It is also found that the training effect of LTS remained 37%, 58%, and 25% in obstacle height of 30%, 40%, and 50%, respectively. Lead foot showed the greater detraining effect of coordination compared with trail foot, and SF (shank and foot) coordination revealed better detraining effects of coordination compare with TS (thigh and shank) in both feet. Based on the findings, a 8 week water exercise give an positive effects to the elderly in terms of segment cooperation which potentially helps reducing their accident falls. The magnitude of detraining may also help the elderly to find the retraining moment.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제48권1호
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• pp.50-58
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• 2022

Objectives: Osteoarthritis (OA) is the most prevalent and disabling joint disease in the world. Temporomandibular joint (TMJ) exercise is a widely used treatment and could be a beneficial and long-term tool for treating TMJ OA. The present study aims to evaluate the effects of therapeutic exercise in the conservative treatment of TMJ OA. Materials and Methods: A single-group experimental pre-post test was performed. We included patients who met the diagnostic criteria for TMJ OA. Outcome variables were pain intensity (visual analogue scale), functionality (Helkimo index), and structural changes (ultrasound). Follow-up periods were at months 1, 3, and 6. The intervention included a home-based program with thermotherapy, manual therapy, and therapeutic exercise during the entire follow-up period. Results: We included 15 patients and 26 joints, all women with a median age of 57 years (range, 49-62 years). Median change in pain intensity on joint palpation, mouth opening, and at rest at the first month was 47.5 mm, 51 mm, and 60 mm, respectively, and 48 mm, 49.5 mm, and 42.5 mm, at six months (P=0.001). The Helkimo index showed significant improvement in medians from baseline severe dysfunction (17 points) to minimal dysfunction at three and six months (2 points) (P=0.001). Ultrasound showed improved disc position. Conclusion: This study demonstrated significant improvements in pain, function, and joint disc position and represents a valuable tool for the long-term treatment of patients with TMJ OA.

• 대한의용생체공학회:의공학회지
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• 제31권3호
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• pp.199-209
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• 2010

The locking compression plates-distal femur(LCP-DF) are being widely used for surgical management of the extra-articular complex fractures of the distal femur. They feature locking mechanism between the screws and the screw holes of the plate to provide stronger fixation force with less number of screws than conventional compression bone plate. However, their biomechanical efficacies are not fully understood, especially regarding the number of the screws inserted and their optimal configurations. In this study, we investigated effects of various screw configurations in the shaft and the condylar regions of the femur in relation to structural stability of LCP-DF system. For this purpose, a baseline 3-D finite element (FE) model of the femur was constructed from CT-scan images of a normal healthy male and was validated. The extra-articular complex fracture of the distal femur was made with a 4-cm defect. Surgical reduction with LCP-DF and bone screws were added laterally. To simulate various cases of post-op screw configurations, screws were inserted in the shaft (3~5 screws) and the condylar (4~6 screws) regions. Particular attention was paid at the shaft region where screws were inserted either in clustered or evenly-spaced fashion. Tied-contact conditions were assigned at the bone screws-plate whereas general contact condition was assumed at the interfaces between LCP-DF and bone screws. Axial compressive load of 1,610N(2.3 BW) was applied on the femoral head to reflect joint reaction force. An average of 5% increase in stiffness was found with increase in screw numbers (from 4 to 6) in the condylar region, as compared to negligible increase (less than 1%) at the shaft regardless of the number of screws inserted or its distribution, whether clustered or evenly-spaced. At the condylar region, screw insertion at the holes near the fracture interface and posterior locations contributed greater increase in stiffness (9~13%) than any other locations. Our results suggested that the screw insertion at the condylar region can be more effective than at the shaft during surgical treatment of fracture of the distal femur with LCP-DF. In addition, screw insertion at the holes close to the fracture interface should be accompanied to ensure better fracture healing.

• 대한치과교정학회지
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• 제18권1호
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• pp.189-207
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• 1988

In almost all biologic systems, mechanically induced electric charge separation is a fundamental phenomenon. Since the hypothesis was established that the generation of electric potentials in bone by mechanical stress including muscular force might control the activity in bone by mechanical stress including muscular force might control the activity of osseous cells and their biopolymeric byproduct, the concept of electrically mediate growth mechanism, which involves biological growth and bone remodeling by any means, in living systems has been applied clinically and experimentally to orthopedic fracture repair, the regulation of orthodontic tooth movement, epiphyseal cartilage regeneration, etc. On the other hand, recent numerous research data available show apparently that the mandibular condyle has the characteristics of growth center as well as growth site. In addition, there exists a considerable difference of opinion as to the role of external pterygoid muscle in condylar growth. In view of these evidences, this. experiment was performed to investigate the effect of the galavic current on the growth of the mandible and condyle for elucidating the nature of condylar growth. The bimetallic device was composed of silver and platinum electrode connected with resistor (3.9 Mohm), which was expected to produce galvanic current of 23.6 nA according to the galvanic principle. The 25 Sprague-Dawley rats were divided into two group, 2 week group comprising 8 animals exposed to satanic current for 2 weeks and 3 control animals not exposed for 2 weeks, 4 week group comprising 10 animals in experimental group and 4 animals in control group applied for 4 weeks respectively. The experimental rats were subjected to application of the galvanic current invasively to codylar head surface and the control groups with sham electrode. On the basis of anatomic and histologic data from the mandibular condyle of experimental and control group, the following results were obtained. 1. After 2 weeks, there was no increase of mandibular size in experimental group over that of the control group. 2. After 4 weeks, the size of the condylar head was larger in experimental group than that of the control. 3. In 2 week group, the thickness of the mitotic compartment and hypertrophic chondroblastic layer was increased in experimental group. 4. In 4 week group, the number and the size of the hypertrophic chondroblasts were increased significantly on experimental group over that of the control group. 5. The application of the satanic current caused an increase in chondrocytic hypertrophy and intercellular matrix in both groups.

• Journal of Korean Neurosurgical Society
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• 제30권10호
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• pp.1210-1219
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• 2001

서 론 : 후방 경유 경추 융합을 위한 후관절 금속판 고정술은 외상성 및 퇴행성 불안정성의 치료에 효과적인 방법이다. 후관절 금속판 고정의 안정성은 여러 가지 인자에 의해 결정된다. 이중 하나가 나사못의 삽입깊이이다. 이 방법이 처음 소개될 때에는 양피질골성 삽입이 이용되었다. 외과의사의 관심은 어떻게 안전하면서 생역학적으로 강력한 고정을 얻느냐에 있다. 목 적 : 이 연구의 목적은 사체에서 단피질성과 양피질성 나사못 삽입술을 시행한 후 안전성, pull-out 강도, 방사선학적 특성을 분석하고 나사못의 삽입에 대한 교육 훈련의 수준에 따른 영향을 평가하는데 있다. 방 법 : 평균 나이 78.9세인 21구의 사체에 대하여, Magerl의 기술을 변형하여 C3-C6(n=168)까지 3.5mm AO 나사못을 양쪽 후관절에 삽입하였다. 수술중 방사선 사진영상은 사용되지 않았다. 오른 쪽(단피질성 삽입)은 14mm 나사못(11mm의 유효 길이)을 이용하고, 왼쪽은 양피질성 삽입을 시도하였다. 각 사체는 3개의 군으로 나누어 척추 수술 수련의 수준이 다른 받은 3명의 척추 외과 의사들(전임 강사, 임상 강사, 수석 레지던트)이 수술을 시행했다. 수술 후 경추를 떼어내어 나사못의 위치를 육안적으로 확인하고 방사선학적으로 안정성과 삽입 위치 (1,2,3)를 평가하였다. 척수, 후관절, 신경근과 척추 동맥에 대한 나사못의 위치를"만족할 만한","위험한", 그리고"직접적인 손상"으로 구분하였다. material testing machine을 이용하여 모든 나사못에 대해서 Pull-out 강도를 측정하였다. 결 과 : 대다수의 나사못(92.9%)은 만족할 만한 상태였다. 전예에서 척수에 대한 위험성은 없다. 오른 편(단피질성 : 14mm) 나사못의 98.9%는"만족할 만한"에 속했다. 그리고 왼쪽 편(양피질성)의 68.1%는"만족할 만한"에 속했다. 양피질성 나사못 군에서 5.8%의 척추 동맥에 대한 직접적인 손상이 있었고 신경근의 직접적인 손상 발생율은 17.4%였다. 반면에 단피질성 나사못 군에서는 이들에 대한 직접적인 손상은 없었다. 양피질성 나사못에서 보인"직접 손상"의 거의 대부분은 외과 의사의 경험 부족으로 발생하였다. 나사못의 안정성과 삽입 위치 사이에는 특별한 관련이 없었다. 모든 나사못의 pull-out 강도는 $542.0{\pm}296.6N$였다. 단피질성에 있어서의 pull-out 강도($519.0{\pm}289.9N$)와 양피질성($565.2{\pm}306N$) 나사못에는 아무런 통계학적으로 의미있는 차이점을 발견할 수 없었다(p>0.05). 나사못 삽입위치와 pull-out 강도 사이에는 의미있는 차이가 없었다. 결 론 : 이번 연구는 경추 후관절 나사못 고정술시 단피질성과 양피질성 나사못의 안정성과 효능을 집중적으로 알아보았다. 명백한 것은 14mm의 나사못(효과적인 길이는 11mm)이 보다 긴 양피질성 나사못 보다 손상의 위험이 훨씬 낮고 거의 동등한 pull-out강도를 갖는다는 것이다. 또한, 수술시 방사선 영상을 사용할 수 없을 때, 훈련과 축적된 경험에 의해 나사못 삽입의 정확성과 안전성이 향상될 수 있다.