응력완화용 완충재를 사용한 알루미나와 Ni-Cr-Fe 합금의 접합

이우천 대한금속재료학회(대한금속학회) 1995 대한금속·재료학회지 Vol.33 No.8

In order to prevent the cracking and fracture generated in the alumina/Inconel 600 joints after cooling, three types of insert materials with Ag-Cu-Ti filler metals was used in the joints. Effect of insert materials on the crack formation of the joints was investigated. The joints free from cracks were obtained when the laminates consisting of niobium of 250 ㎛ thick and copper of 50 ㎛ thick were used as insert materials. For the joints cooled at the rate of 4.8 ℃/min after brazing at 1113 K for 1.2 ks, the average shear strength was 75.7 MPa and the strength distribution showed the mixed mode.

염좌 후에 발생한 족관절 누공

이우천,김정훈,송재국,문정석,Lee, Woo-Chun,Kim, Jung-Hoon,Song, Jae-Kuk,Moon, Jeong-Seok 대한족부족관절학회 2002 대한족부족관절학회지 Vol.6 No.2

Purpose: To investigate the clinical features of fistulas of the ankle joints. Materials and Methods: Seven fistulas in seven patients were reviewed during Apr. 2000 to Mar. 2002, retrospectively. There are five men and two wemen. Average age was 47.7 years (range, 42-65 years). Average follow-up period was 1.4 years. There were six cystic lesions after ankle sprain and one patient with persistent discharge after excision of bursa over lateral malleolus. Results: Duration from injury to presentation was average 9.8 years. The site of preoperative swelling was mostly over the lateral malleolus in five patients. In one patient, the area of swelling was extended to the anterolateral ankle joint and in another patient there was extensive swelling from Achilles tendon to the anterolateral ankle joint. Concomitant symptoms were instability in three patients, pain and instability in three patients. Methods of surgery were simple repair in one, modified Brostrom in three, augmentation with periosteal flap in addition to modified Brostrom in two and Chrisman-Snook in addition to augmentation with periosteal flap and modified Brostrom in one. There were no recurrence of instability as well as fistula. Conclusion: We think that the fistula of the ankle joint should be included in the differential diagnosis of the cystic lesion over the lateral malleolus and the result of surgical treatment would be satisfactory in most cases.

족관절 퇴행성 관절염의 방사선학적 분석

이우천,강영훈,Lee, Woo-Chun,Kang, Yeong-Hun 대한족부족관절학회 2005 대한족부족관절학회지 Vol.9 No.2

Purpose: This study was performed to investigate the radiological characteristics of the degenerative arthritis of the ankle using the standing radiographs. Materials and Methods: From June 2001 to May 2005, 36 patients (56 ankles) who were treated for osteoarthritis of ankle were analysed. Angle of tibial shaft and tibial joint surface on AP view (TSA), angle of tibial joint surface on lateral view (TLS), tibial and medial malleolus angle (TMM) and talo-1st metatarsal angle were checked on standing radiograph. The patients with medial joint and total joint involvement were categorized into three stages according to the location of involvement. The degree of joint space narrowing was categorized into two groups. Results: There were no significant differences in TSA, TLS, TMM and talo-1st metatarsal angle with regard to the stage of arthritis. However, the difference between the less severe group and the severe group existed. Conclusion: Angular deformity was not correlated with stage, but correlated with severity. The deformity of distal tibial articular surface does not seem to be a cause of primary osteoartiritis, but rather a result from it.

성인 당뇨병 환자의 족부와 신발에 대한 조사

이우천,Lee, Woo-Chun 대한족부족관절학회 2004 대한족부족관절학회지 Vol.8 No.2

Purpose: To investigate the status of foot, preventive foot care and appropriateness of shoe size in patients with diabetes. Materials and Methods: One hundred and sixty-five patients who visited endocrinology clinic due to clinically proven diabetes mellitus were studied. Average age was 59.3 years (range, 36-90 years) and average duration of diabetes was $9.6{\pm}8.2$ years. Patients were questioned about their basic educational level and their foot and ankle problems. Physical examination of the foot was done including sensation testing of four areas of plantar surface with the 5.07 monofilament. Both feet and shoes were measured for width, length and the height of toes and toebox. Shoes were defined as properly fitting the foot if it is 5mm wider than the foot, and $20{\pm}30\;mm$ longer than the foot, and the height of toebox is more than 5mm higher than the height of the toes. Results: 48.5 percent of the patients were educated about how to select an appropriate shoewear. 47.3 percent of the patients had symptoms of neuropathy and 42.4 percent of patients were unable to feel the monofilament in at least one area. 25.5 percent of the patients had appropriate shoes in length, 63.6 percent of the patients in width, and 72.7 percent of the patients in the height of toebox. Conclusion: This study suggets that more patients needs to be educated about foot care and appropriate shoes which have adequate height of toebox as well as the length and width.

단순 방사선 상에서 발견할 수 없었던 거골 골연골 병변의 MRI 소견과 관절경 소견

이우천,심재찬,최덕신,Lee, Woo-Chun,Shim, Jae-Chan,Choi, Deog-Shin 대한족부족관절학회 2002 대한족부족관절학회지 Vol.6 No.2

Purpose: To investigate the MRI and arthroscopic findings of osteochondral lesion of the talus which looked normal on plane radiography. Materials and methods: We investigated the MRI and arthroscopic findings of seven osteochondral lesions in which there were no abnormal finding on plane radiography and no cystic changes on MRI. Average age was 31 years(range, 19-43 years). Arthroscopic findings were classified according to the Ferkel's criteria. Results: History of injury was reported in all cases and the average duration from injury to presentation was 4 years and 4 months. Low signal change in T1WI was found in 6 of 7 lesions, no signal change in 1 case. Low signal change in T2WI was found in 4, no signal change in 3. 6 STIR images were obtained. High signal change was found in 3, no signal change in 2 and intermediate signal change was in 1. Arthroscopic grading was A in 1, C in 1, D in 2 , E in 1 and F in 2. We could not find any correlation between the findings on MRI and arthroscopic examination. Conclusion: We suggest arthroscopic examination is needed for accurate diagnosis of the osteochondral lesions of the talus which looked normal on plane radiography, because they have various MRl findings and high likelihood of existence of unstable cartilage lesions.

증세가 있는 비골하 부 골

이우천,고한석,권강진,김승우,Lee, Woo-Chun,Ko, Han-Suk,Kwon, Kang-Jin,Kim, Sung-Woo 대한족부족관절학회 2001 대한족부족관절학회지 Vol.5 No.2

Purpose: To investigate clinical features and treatment of os subfibulare Materials and Methods: This is a retrospective study on twenty-eight patients who have symtoms associated with os subfibulare. We reviewed charts and radiographs. Thirteen patients were treated surgically and fifteen patients were treated conservatively. We analysed clinical results in 25 patients who were followed for more than one year. Results: Duration from the onset of symtoms to treatment was more than six months in twelve of thirteen surgically treated cases, and in only two of fifteen conservative treated cases. Surgical procedures were internal fixation of the os subfibulare in two patients, and resection of os subfibulare and ligament reconstructions in eleven patients. Clinical results were excellent in six, good in three and poor in two of operatively treated patients. In conservatively treated patients, five excellent, five good, one fair and one poor clinical results were obtained. Conclusion: Os subfibulare is not necessarily a cause of instability and pain, but in cases with chronic pain and/or instability, surgical treatment would result in satisfactory result.

족관절 족배 굴곡 각도의 측정

이우천,박현수,한영길,조정진,장병춘,이재율,엄기혁,라종득 대한스포츠의학회 1998 대한스포츠의학회지 Vol.16 No.1

Clinical measurement of ankle motion includes tarsal and tarsometatarsal as well as tibiotalar motion, and it is affected by knee position and weight-bearing. The purpose of this study is to determine the problem of each method of measurement, the difference in the angles measured by various methods, and to suggest a reference data to assess the tightness of the Achilles tendon. Dorsiflexion range of 80 healthy ankles was measured by 8 different methods. The dorsiflexion range of the Group 1, 2, 3 was measured when the foot was not weight-bearing and the knee was flexed 90° with the foot in inversion, eversion, and neutral position respectively and the means and standard deviation of each group were 13.8±5°, 27.5°±6° and 23.4±5° respectively. The dorsiflexion range of the Group 4, 5, 6 was measured with the foot in inversion, eversion and neutral position when the foot was not bearing weight, and the knee was extended and the means and standard deviations of each group were -6±5°, 10±4° and 7±4° respectively. The dorsiflexion range of the Group 7 and 8 was measured with the knee in flexed or extended position, when the subject was bearing weight and the mean and standard deviation of each group were 44±7° and 38±7° respectively. There were statistically significant differences between each group within the Groups 1·2·3, Groups 4·5·6, Groups 3·6 and Group 7·8(p<0.01). In conclusion, the measurement of dorsiflexion range of ankle motion need to be done with the foot in neutral position to minimize the effect of the shape of the foot or the motion in the foot. Measurement in weight-bearing condition is not recommended, because it might be affected by the degree of weight bearing. The difference in the dorsiflexion range between the Group 3(measured with the knee flexed) and the Group 6(measured with the knee extended) is 15.9±4.9°, and it be used as a reference angle to assess the presence of Achilles tightness.

비골건의 병변 : 3례 보고 Report of Three Cases

이우천,정현우,라종득 대한스포츠의학회 2000 대한스포츠의학회지 Vol.18 No.2

Recently peroneal tendon lesion is considered as a cause of lateral ankle and foot pain. We have treated three cases of peroneal tendon lesions operatively and followed for more than fourteen months. One case was a partial longitudinal tear of peroneus ongus tendon, the other case was a complete longitudinal tear of peroneus brevis, and the last case was a complete rupture of peroneus brevis caused by osteochondroma in the calcaneus. The result of the surgical treatment was satisfactory.

제 1 중족 설상골 관절의 골극 -1례 보고-

이우천,박현수,최두식,라종득,Lee, Woo-Chun,Park, Hyun-Soo,Choi, Deu-Sick,Rha, Jong-Deuk 대한족부족관절학회 1999 대한족부족관절학회지 Vol.3 No.1

Slight protrusion of the dorsum of midfoot without degenerative arthritis is common and usually can be treated by avoiding pressure of the shoe. Primary or posttraumatic degenerative arthritis accompanied by severe functional disability is treated by realignment and arthrodesis of the involved joints. We report a case of osteophytic changes in the form of lipping at the base of the first metatarsal and medial cuneiform which was treated by resection of the spurs. The cause of these spurs may be the congenital coalition of the first metatarsocuneiform joint.

A Study on Export Competitiveness Improvement of Korean Biosimilar’s Industry

이우천,박세훈 한국무역상무학회 2018 貿易商務硏究 Vol.80 No.-

As we have seen in this paper, the uncertainty of the biosimilar licensing system are obstacles to the growth of the biosimilar industry in Korea and the expansion of global competitiveness. In order to grow the biosimilar industry and strengthen international competitiveness, it is necessary to develop the quality and management regulations of the biosimilar industry in Korea to the same level as in Europe and the US, and to improve the licensing system in order to reduce unnecessary procedures and costs. If the establishment of such a system is delayed, the international competitiveness of the biosimilar industry in Korea will be weakened. Therefore, the following efforts are needed to enhance export competitiveness of biosimilar-related industry. First, it is necessary to develop biopharmaceutical and build regional portfolio strategies. Second, it is necessary to secure opinion leaders and excellent partners to strengthen overseas sales capabilities. Third, it is necessary to preemptively build biosimilar-related systems.