• Journal of Korean Foot and Ankle Society
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• v.9 no.2
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• pp.167-172
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• 2005

Purpose: We report our results of arthroscopic treatment of symptomatic avulsion fracture of the malleolus in chronic ankle pain, and also analyzed the clinical and radiological features for evaluating the good candidate for arthroscopic treatment. Materials and Methods: Fourteen patients who were diagnosed with intra-articular avulsion fractures of the malleolus received arthroscopic surgery and were followed up for at least a year. The clinical and radiological characters including MRI and arthroscopic findings were reviewed. Clinical assessments were done according to the AOFAS score system. Results: There was a history of inversion type of the injury in most cases and local tenderness of lesion site was a unique. MRI study showed thickened anterior talofibular ligament (ATFL) in 8 cases (57%) and discontinued ATFL in 3 cases (21%). Enhanced signal surrounding soft tissue corresponding to synovial inflammation and impingement was found in 12 cases (86%). Preoperative score of all patients were $74.0{\pm}5.5$, which improved to $89.3{\pm}6.7$ at the follow-up after the treatment (P<0.001). Conclusion: Most patients had history of injury and localized tenderness in the area coinciding with radiological findings. Thickened ATFL and contrast enhancement around the ossicle were frequently found. Symptomatic avulsion fractures of the malleolus associated with the clinical and radiological findings above could be a good candidate for arthroscopic treatment.

• Journal of the Korean Society for Nondestructive Testing
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• v.22 no.4
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• pp.386-392
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• 2002

Ultrasonic has been proposed as an attractive means of detecting bone loss. There have been several commercial ultrasound devices developed for measuring the heel to predict fracture at other bones. However, these devices select only single point of heel bone as measurement site. It causes poor assessment of bone quality due to the error of transducer positioning. In an effort to improve current ultrasound systems, we evaluated the linear scanning method which provides better prediction of bone quality and an accurate image of bone shape. The system used in this study biaxially scans a heel bone using automated linear scanning technique. The results demonstrated that the values of ultrasound parameters varied with different positions within bone specimen. It has been also found that the linear scanning method could better pre야ct bone quality, eliminating the error of transducer positioning.

• Archives of Reconstructive Microsurgery
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• v.16 no.1
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• pp.48-51
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• 2007

There could be several methods for trochanteric reconstruction including local flap, pedicled perforator flaps, free flap, etc. We performed greater trochanteric reconstruction with lumbar artery perforator free flap in some aberrant method. So we report this experience with review of literatures. A 42-year-old man visited our hospital with a large soft tissue defect in his left greater trochanteric area by traffic accident. The patient had wide skin and soft tissue defect combined with open femur fracture. During one month period of admission, he underwent femur open reduction and wound debridement four times. After that we planned thoracodorsal perforator free flap reconstruction. The flap was outlined as large as $20{\times}15\;cm$ and elevated in a suprafascial plane from the lateral border. During intramuscular perforator dissection, we found that two 1.5 mm diametered perforator vessels coursed inferomedially toward second lumbar region. Finally the flap became lumbar artery perforator flap based on second lumbar artery perforator as a main pedicle. After flap transfer, the perforator vessels were connected with inferior gluteal artery and vein microsurgically. The operation was successful without uneventful course. We found no significant postoperative complication and donor site morbidity during six months follow up periods. Lumbar artery perforator flap could be an alternative procedure for thoracodorsal perforator flap in some patients with anatomic variant features.

• Archives of Reconstructive Microsurgery
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• v.2 no.1
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• pp.20-28
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• 1993

From 1981 to 1991, twenty one vascularized bone grafts had been performed for the treatment of large bone defects of the extremities, with average follow-up of 65.4 months. Fibulae were used in 15 patients Including two cases of osteocutaneous flap, iliums in 5 including two of osteocutaneous flap, and osteocutneous rib in one. Ten of these patients were treated for segmental defects derived from trauma or infection sequelae of long bones, while eight for locally aggressive benign or malignant bone tumors ; and three for congenital pseudarthrosis of tibia. The location of the lesions were 8 cases in tibia; 7 in humerus ; 3 in forearm bone ; 2 in foot ; and 1 in femur. The length of bone defects were averaged as 10 cm, ranging from 3 to 17.5. In eighteen patients(85.7%), the operation was successful. The duration from operation to bony union was average 5.1 months on successful cases, and three of them needed additional procedures, such as bone graft and electrical stimulation to promote bony union. Local recurrence was found in one case of chondrosarcoma, resulting in AK amputation. Wound infections were noted each one case on donor or recipient site. In five cases, the fracture of grafted bone, which united with cast immobilization in four, occurred average 16.7 months after operation.

• Archives of Reconstructive Microsurgery
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• v.2 no.1
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• pp.29-41
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• 1993

Recent advances in microsurgery have made it possible to provide a continued circulation of blood to the grafted bone so as to ensure viability. With the nutrient blood supply preserved, healing of the graft to the recipient bone is facilitated without the usual replacement of the graft by creeping substitution. We reviewed 34 cases of vascularized osteocutaneous fibular transfers to the infected tibial defect complicated with skin defect, which were performed from May, 1982 to January, 1992, and the following results were obtained: 1. Despite of uncontrolled bone infection with skin defect, the vascularized osteocutaneous fibular flap transfer could be performed. 2. In the vascularized osteocutaneous fibula transfer, the patency of anastomoses could be indirectly monitored by observing the color of the skin flap. 3. The vascularized fibula had been hypertrophied with bony union during the follow-up period of 13 months to 6 years and 4 months(average, 30 months) and there was no resorption of the grafted fibula. 4. There was no fracture of the grafted fibula in parti resection of involved tibia. 5. The hypertrophic potentiality of grafted fibula could be inhibited by the infection status as operation site.

• Journal of the Korean Society for Railway
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• v.13 no.2
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• pp.179-185
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• 2010

In order to secure safety for the buckling and fracture of continuous welded rail and improve the efficiency of maintenance work, it is very important that grasp the characteristics of rail temperature. Recently, the maximum air temperature in summer season rises gradually and the minimum air temperature in winter season is decreasing gradually due to the climate change. Therefore, these phenomenon influences in the change amount of yearly rail temperature and can cause change of laying and maintenance temperature. In this study, actual measurement of rail temperature including climatic factors is carried out by constructing the temperature and climate measurement system as realistic as possible. Through the intensive investigation of actual data, it is founded that the existing prediction formulas for rail temperature may be used only in certain climatic conditions (certain combination of climatic factors). It may be more reasonable that the rail temperature considering actual climatic factors in site is predicted on probabilistic approach.

• Journal of Ocean Engineering and Technology
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• v.4 no.1
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• pp.88-100
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• 1990

Among the test methods to evaluate stress-corrosion cracking(SCC) on the basis of fracture mechanics, constant displacement(bolt) loading method using modified-WOL specimen is practically convenient. In this test method, compliance formula is generally required to calculate load(consequently $K_{ISCC}$). There are many problems in using the analytic compliance formula to calculate $K_{ISCC}$, so we had proposed the experimental $K_{ISCC}$ evaluation technique in the previous report. This study has employed the slightly altered configuration of modified-WOL specimen made of weldable structural stee(BS360-50D). With these specimens, stress-corrosion tests have been performed in $H_2S$ gas saturated 20% HCl solution. Through the test, the problems as mentioned earlier have been discussed again, and the proposed evaluation technique has been verified. And the stress-corrosion cracks and hydrogen blisters have been investigated in the initiation step with the aids of metallurgical micrographs, SEM fractographs, and EPMA analysis. The inclusions segregated in the mid-thickness region traps hydrogen to produce the hydrogen blistering. The applied or residual stress does not contribute the occurrence of the blister. Hydrogen absorbed into the mid-thickness region is consumed to produce the blistering so that stress-corrosion crack could hardly be detected at that region. The stress-corrosion cracks initiate from the inclusions and propagate in radial pattern. And the initiation site is remote from the crack tip and is inclined from the crack plane, which is assumed to be caused by the triaxial stress and the amount of the absorbed hydrogen.

• Archives of Plastic Surgery
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• v.33 no.6
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• pp.688-694
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• 2006

Purpose: Reconstruction of the craniofacial defects can be carried out with autogenous tissues, allogenic implants, or alloplastic materials. Titanium mesh systems have been used for bony reconstruction in non load-bearing areas. They offer several advantages: immediate availibility without any donor site morbidity, easy handling, stable 3-D reconstruction, and low susceptibility to infection. The aim of this study is to evaluate the usefulness and complications of titanium mesh system in the reconstruction of the craniofacial defects. Methods: From Jan. 2000, to Dec. 2004, we performed reconstruction of craniofacial bone defects in 21 patients who had benign or malignant tumor and fracture events in the cranium, orbit, nasal bone, maxilla, zygoma and the mandible. The size of the defects ranged from $1.0{\times}1.5cm$ to $12{\times}10cm$. Two different mesh systems, micro-titanium augmentation mesh and dynamic mesh was used for bony reconstruction in non load-bearing areas. The patients were evaluated from 1 to 4 yrs clinically and radiographically with a mean follow up period of 1.5 yrs. Results: There were no serious complications, including wound infection, foreign body reaction, exposures or loos of the mesh, central infection and pathologic findings of bone around mesh exception of one patient, who had expired of skull base tumor recurrence. Long-term stability of the reconstructions and the overall functional and aesthetic outcome was excellent. Conclusion: Our experiences demonstrate that the Titanium mesh system is a relatively safe and efficient method in the craniofacial reconstruction and have broadens our choices of therapeutic procedures in the craniomaxillofacial surgery.

• Journal of the Korea Safety Management & Science
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• v.18 no.1
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• pp.9-15
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• 2016

In this study, the current regulations to be adequate in industrial site have to be renew in order to prevent the fatal injuries by mobile cranes. Fatal injury analyses were conducted with several accident cases by the mobile cranes. For each accident, the causes of the injuries were examined and proper safety measures were proposed. This study proposed a revision of the standard guideline as an accident prevention measures through in-depth analysis of fatal accidents. First, fatality rate per 10,000 persons by the mobiles cranes was 0.57 in 2011. Second, the in-depth analysis of the mobile crane accidents showed that the main factors of the accidents were the overturn of mobile crane, the fracture of connection part between mobile crane boom and rope, the breaking of rope and the misunderstanding over the signal between a mobile crane driver and workers around a mobile crane. Third, the order of high defection of connecting parts was bucket bolt, bracket and extension parts. Fourth, since there were several cases of overturn of mobile crane by itself in the in-depth analysis of the mobile crane, the over slop-proof device was proposed as the main alternative in this study. Fifth, the revision of standards of safety factor that shall be more than 10, of connecting parts of mobile crane was proposed.

• Composites Research
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• v.26 no.5
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• pp.328-333
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• 2013

In this study, bone plate made of glass/polypropylene composite material which was applied to an artificial bone was tested to check the service ability under fatigue loading. To check serviceability of composite bone plates fatigue test was carried out considering changes in the moisture absorption rate, locking position of screws and loading condition. Test results showed that all the tested specimens had the fatigue life more than one million cycles which was much higher fatigue life than the expected value of 650,000 cycles. Screw position was not critical impact on the deformation of the fracture site. In this paper, the mechanical performance of the glass/polypropylene composite was verified by fatigue test under various water absorption conditions, and this result may give useful information on the design of composite bone plate.