Anatomical versus Non-Anatomical Single Bundle Anterior Cruciate Ligament Reconstruction: A Cadaveric Study of Comparison of Knee Stability

임홍철,윤용철,왕준호,배지훈 대한정형외과학회 2012 Clinics in Orthopedic Surgery Vol.4 No.4

Background: The purpose of this study was to compare the initial stability of anatomical and non-anatomical single bundle anterior cruciate ligament (ACL) reconstruction and to determine which would better restore intact knee kinematics. Our hypothesis was that the initial stability of anatomical single bundle ACL reconstruction would be superior to that of non-anatomical single bundle ACL reconstruction. Methods: Anterior tibial translation (ATT) and internal rotation of the tibia were measured with a computer navigation system in seven pairs of fresh-frozen cadaveric knees under two testing conditions (manual maximum anterior force, and a manual maximum anterior force combined with an internal rotational force). Tests were performed at 0, 30, 60, and 90 degrees of flexion with the ACL intact, the ACL transected, and after reconstruction of one side of a pair with either anatomical or non-anatomical single bundle ACL reconstruction. Results: Under manual maximal anterior force, both reconstruction techniques showed no significant difference of ATT when compared to ACL intact knee state at 30° of knee flexion (p > 0.05). Under the combined anterior and internal rotatory force, non-anatomical single-bundle ACL reconstruction showed significant difference of ATT compared to those in ACL intact group (p < 0.05). In contrast, central anatomical single bundle ACL reconstruction showed no significant difference of ATT compared to those in ACL intact group (p > 0.05). Internal rotation of the tibia showed no significant difference in the ACL intact, the ACL transected, non-anatomical reconstructed and anatomical reconstructed knees. Conclusions: Anatomical single bundle ACL reconstruction restored the initial stability closer to the native ACL under combined anterior and internal rotational forces when compared to non-anatomical ACL single bundle reconstruction.

제 18 차 정기학술대회 초록집 : 39. 만성 신부전증 환자에 있어서 대퇴 사투근의 자연적 파열 - 증례 보고 -

임홍철,심재학,최병섭,남혁우,홍명표 대한슬관절학회 2000 정기학술대회 Vol.- No.-

Measurements of dielectric constants of soil to develop a landslide prediction system

임홍철 국제구조공학회 2011 Smart Structures and Systems, An International Jou Vol.7 No.4

In this study, the measurements of the dielectric constants of soil at 900 MHz and 1 GHz were made to relate those properties to the moisture content of the soil. This study’s intention was to use the relationship between the dielectric constant and the moisture content to develop a landslide prediction system. By monitoring the change of the moisture content within the soil using ground penetrating radar (GPR) systems in the field, the possibility of a landslide is expected to be detected. To establish a database for the dielectric constants and the moisture content, the measurements of soil samples were made using both an open-ended dielectric coaxial probe and the GPR. Based on the measurement results, correlations between the GPR and reflector for each frequency at 900 MHz and 1 GHz were found for the dielectric constants and the moisture content. Finally, the mechanism of the measurement device to be implemented in the field is suggested.

Top Down 공사의 선기둥 수직도 계측

임홍철,신천균,김승원 한국건축시공학회 2006 한국건축시공학회지 Vol.6 No.4

The purpose of this study is to measure the straightness of prefounded columns during underground construction stages. There are several causes of an error of prefounded column: ① columns connected by welding or bolting, ② by placement of concrete and aggregates around columns, ③ movement during construction, and ④ load applied during construction. The error of column straightness is different for each column, and the tilting of columns is shown in one or two directions between floors. The additional loads caused by the error of straightness may give damage to buildings. This paper presents the measurement results of column straightness, and thus providing a basis for further analysis.

골유합술식을 이용한 대퇴경부 골절의 치료

임홍철,전승주,손원용,김기성 대한골절학회 1999 대한골절학회지 Vol.12 No.1

We reviewed respectively the results of treatment of femoral neck fracture using osteosynthetic methods, in 29 patients who were treated at the Department of Orthopedic Surgery, Guro Hospital, Korea university, from January 1991 to December 1995. 20 cases were stabilized by cannulated hip screw, 6 cases by compression hip screw and 3 cases by Knowles pin. With the average follow up of 26 months (12 - 45 months ), we analyzed the cause of injury with age, fracture types by Garden' s method, the accuracy of reduction by Garden' s alignment index and the functional results of the hip by Harris hip score and walking capacity. The adequacy of reduction by Garden' s alignment index were as follows: anatomical in 14, acceptable in 12 and poor in 3 cases. The functional results by Harris hip score and walking capacity were as follows: excellent in 21, good in 3, fair in 2 and poor in 3 cases. Complications after treatment of femoral neck fracture were one case of AVN, one case of non-union and two cases of combination of AVN and non-union. All these complications were developed in displaced femoral neck fracture with poor quality of reduction and directly correlated with initial displacement of fracture and reversely correlated with adequacy of reduction Our conclusions are that treatment of femoral neck fracture using osteosynthesis is favorable in young age regardless 'of initial displacement and in old age without osteoporosis and displacement and satisfactory results are produced from acceptable to anatomical reduction of fracture.

건축기술 ( 구조 ) - 건축기술과 건축형태의 연관성에 관한 고찰 ( 2 ) - 구조공학적 관점에서 - ( The Correlation between the Building Technology and the Architectural Form ( 2 ) - From the Aspects of Structural Engineering - )

임홍철,박재승 대한건축학회 1999 建築 Vol.43 No.2

굴착순서에 따른 Top Down 선기둥 지지력 산정

임홍철,황희선 한국건축시공학회 2006 한국건축시공학회지 Vol.6 No.4

Top Down method is more widely used in downtown construction, recently. As underground construction constitutes a significant portion of the total construction cost and time in Top Down construction, it is important to develop a construction method to reduce the time required in underground works. The purpose of this study is to analyze load carrying capacity of Top Down prefounded columns on different excavation schedule. When several floors are excavated, the valid buckling length of prefounded column is increased and allowable buckling stress is decreased. The result shows that all columns are safe in buckling down to B3 story whether 2 or 3 stories are excavated. However, several columns are not safe from B4 story when 2 or 3 stories are excavated straightly. With these results, a process can be designed that the first three stories in the basement are excavated, and then excavate B4 story after placing concrete on B1 and B2 floor.

40세 이상에서 발견된 외측 원판형 연골의 임상분석

임홍철,노경선,정효섭,Lim, Hong-Chul,Noh, Kyoung-Sun,Jung, Hyo-Sub 대한관절경학회 2006 대한관절경학회지 Vol.10 No.1

목적: 40세 이상의 성인에서 발견된 외측 원판형 연골의 임상적 특징에 대해서 분석하고자 한다. 재료 및 방법: 1994년 3월부터 2004년 3월까지 40세 이상에서 원판형 연골이 발견되어 관절경적 치료후 1년 이상 추시가 가능한 48명의 환자 53예를 대상으로 하였고 환자의 평균 연령은 48.4세($40{\sim}62$세)였다. 환자군을 대상으로 이학적 검사 소견, 단순 방사선 및 MRI 소견, 관절경 소견을 분석하였다. 결과: 전체 53예중 증상 이환 기간은 1년이내가 42예(79.2%)로 대부분을 차지하였고 26예(49.1%)에서 외상의 기왕력이 있었으며, 방사선학적 검사상 대퇴골 외과의 편평화, 외측 구획의 퇴행성 변화가 37예(69.8%)에서 관찰되었다. 또한 내측 구획의 퇴행성 변화는 16예(30.2%)에서 관찰되었다. 슬관절경 검사상 45예(84.9%)에서 원판형 연골의 파열이 관찰되었고 파열이 없었던 경우는 8예(15.1%)였다. 파열형태는 복합형(18예, 40.0%)의 파열 형태가 가장 흔하게 나타났으며 그외 종파열(longitudinal) 12예(26.7%), 수평파열(horizontal) 11예(24.4%), 횡파열(transverse) 4예(8.9%)가 관찰되었고, 내측 연골판 파열을 동반하는 경우는 7예(13.2%)였다. 치료 방법으로는 관절경하 연골판 성형술이 46예(86.8%), 이중 6예에서 연골판 성형술 후 부분적 봉합술을 함께 시행하였으며 연골판 아절제술이 5예(9.4%), 연골판 전절제술이 1예(1.9%), 1예(1.9%)에서 관절경 검사후 슬관절 전치환술을 시행하였다. 결론: 성인의 원판형 연골은 소아의 경우와는 달리 외상의 기왕력을 가지고 있는 빈도가 높으며 가벼운 외상에 의해 증상이 발현된다. 또한 슬관절 내 외측 구획의 퇴행성 변화 등 방사선학적인 변화를 관찰할 수 있어 가능한 보존적인 수술적 치료가 필요할 것으로 사료된다. Purpose: The purpose of this study was to analyze the clinical results of symptomatic lateral discoid meniscus found in adults over 40 years old. Materials & Methods: From March 1994 to March 2004, 53 cases treated for lateral discoid meniscus in 48 patients aged over 40 years with the mean age $48.4(40{\sim}62)$ who were followed up more than 1 year, were analyzed by physical findings, simple X-ray, MRI and arthroscopic exam. Results: Most of the cases (42 cases, 79.2%) had symptoms for less than 1 year duration. 26 cases(49.1 %) out of 53 had trauma history. Simple radiologic evaluation showed that lateral condylar abnormality such as the flattening of lateral femoral condyle, marginal osteophytes, and subchondral sclerosis was seen in 37cases(69.8%). Also medial condyle showed degenerative changes in 16 cases (30.2%). Tear of discoid meniscus in 45 cases(84.9%) were examined by arthroscope and tear was not detected in 8 cases(15.1%). Type of tear was complex(18 cases), longitudinal(12 cases), horizontal(11 cases) and transverse(4 cases). Concomitant medial meniscal rupture was found in 7 cases(13.2%). The simple procedure done was reshaping(46 cases), subtotal resection(5 cases), total resection(1 case) and meniscal repair after reshaping in 6 cases, and arthroplasty was performed after arthroscopic examination in 1 case. Conclusion: Onset of symptom in adult lateral discoid meniscus is usually traumatic in origin. Most cases showed radiologic abnormality such as degenerative change in lateral condyles as well as medial condyles and the results of preservative surgical treatment was the most preferred option in most patients.

주파수 영역 필터링을 통한 콘크리트 시편 내부 레이더 탐사

임홍철,이윤식 한국지진공학회 2002 한국지진공학회논문집 Vol.6 No.4

지진 발생시 건축물의 내부상태를 탐사하는데 있어 콘크리트 구조물의 두께, 철근의 피복깊이, 공동의 유무를 탐사하게 되고, 이것을 통해 건축물의 손상을 추정할 수 있다. 이때 콘크리트 내부를 탐사하는 방법으로 지중 탐사 레이더(ground penetrating radar)가 효과적으로 이용될 수 있다. 기존의 레이더 측정 방법에서는 콘크리트 내부를 탐사하기 위해 시간영역에 있는 데이터로 콘크리트의 유전상수를 구하고 시간을 거리로 환산하여 육안 식별에 의해서 결과를 분석하였다. 본 연구에서는 콘크리트 시편을 측정한 후 측정된 데이터를 주파수 영역으로 변환하여 스펙트럼 분석과 필터링을 통한 방법으로 신호 처리하여 시간영역에서의 데이터 분석능력을 향상 시켰다. 데이터 획득을 위해 주로 사용되는 900MHz, 1GHz, 그리고 1.5㎓ 중심 주파수를 갖는 세 개의 안테나를 사용하여 철근시편을 탐사하였다. 주파수 영역에서 차단 주파수(cutoff frequency)를 1/3 옥타브에 의하여 변화시키면서 저역 통과, 고역 통과, 그리고, 대역 통과 등의 필터링을 하였고, 각각의 중심 주파수에 대한 가장 효과적인 차단 주파수를 찾으려고 했다. 차단 주파수의 범위는 최대 하위 2옥타브에서 상위 1옥타브와 최소 하위 2옥타브에서 하위 1옥타브가 적합하였고, 주파수 영역에서 필터링을 통해 콘크리트 내부 정보 분석력 향상을 위한 토대를 마련하였다. Radar method can be effective in probing concrete structures damaged by earthquake. Data analysis is usually performed in time domain, by considering time delay of the wave due to the dielectric constant of concrete. In this study, improved data analysis has been performed using signal processing scheme of spectra analysis and filtering. Three antenna with 900MHz, 1㎓, and 1.5㎓ center frequency were used to detect a steel bar or delamination in specimens for obtaining data, Frequency spectrum was filtered in low pass, high pass, and band pass varying cutoff frequency with 1/3 octave in frequency domain. The most effective cutoff frequency for each frequency has been determined as the range for 2 octave lower to 1 octave higher and 2 octave lower to 1 octave lower. This result provided a basis in improving data analysis capability using frequency domain filtering.

슬관절 내측부 인대 손상의 보존적 치료

임홍철,심재학,남혁우,왕준호,노영진 대한스포츠의학회 2000 대한스포츠의학회지 Vol.18 No.2

Purpose : The medial collateral ligament injury is the most common injury of the knee. Recently Non-operative treatment has been preferred than operative treatment and most of patients have satisfactory clinical results after non-operative treatment. But a few patients have continuous instability after non-operative treatment, so the purpose of this study is to fine out the cause of persistent symptom. Methods and Materlals : We performed a retrospective study of one hundred thirty seven patients with medial collateral ligament injury treated non-operative from January 1990 to December 1997. W divided patients into two groups: isolated medial collateral ligament injury (groupⅠ): medial collateral ligament injury with concomitant anterior cruciate ligament injury (groupⅡ) and we analysed MRI finding, valgus instability, and Lysholm knee score. Result : At the follow up, three of group Ⅰ, five of group Ⅱ had persistent grade Ⅲ valgus instability. In group Ⅰ, we could find two case of rupture of the proper of medial collateral ligament with inward inversion and one case of concomitant posteromedial compartment injury. We could find the proper rupture of medial collateral ligament with inversion inward in two patients, the injury of posteromedial compartment in one patient. Two patients of group Ⅱ with grade Ⅲ valgus instability had anterior instability with laxity of grafted tendon after anterior cruciate ligament reconstruction. Conclusion : Most of isolated injury of the medial collateral ligament heals wthout operative intervention. But in case of rupture of the proper portion of medial collateral ligament with inversion inward or concomitant injury of posteromedial compartment, we should consider the operative treatment of medial collateral ligament. In case of medial collateral ligament injury with anterior cruciate ligament, it would better to consider the delicate reconstruction of anterior cruciate ligament.