• 한국정밀공학회지
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• 제23권11호
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• pp.126-134
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• 2006

In this study, the effect of stem-end design on contact pressure and stress distribution in revision TKR was investigated using finite element method. The finite element model of tibia, including the cortical bone, the cancellous bone and canal, was developed based on CT images. The implant models with various stem lengths, diameters, friction coefficients, and press-fit effects were considered. The results showed that the longer stem length, the stronger press-fit, the bigger stem diameter, and the higher friction coefficient increased both peak contact pressure and Von-Mises stress distributions. The results supported the clinical hypothesis that peak contact pressure and stress are related to the stem end pain. The results of this study will be useful to design the stem and reduce the end-of-stem pain in revision TKR.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.179-180
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• 2006

In this study, the effect of stem-end design on contact pressure and stress distribution in revision TKR was investigated using finite element method. The finite element model of tibia, including the cortical bone, the cancellous bone and canal, was developed based on CT images. The stem models with various stem lengths, diameters and frictional coefficients, and press-fit effects were considered. The results showed that the longer stem length, the stronger press-fit, the bigger stem diameter, and the higher frictional coefficient increased both peak contact pressure and the highest Von-Mises stress values. We hypothesized that peak contact pressure and Von-Mises stress distribution around the stem, may be related to the stem end pain. The results of this study will be useful to design the stem endand reduce the end-of-stem pain in revision TKR.

• Hip & pelvis
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• 제35권1호
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• pp.40-46
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• 2023

Purpose: A variety of short Exeter stems designed specifically for use in performance of total hip arthroplasty (THA) in primary and revision settings have recently been introduced. Some have been used 'off label' for hip reconstruction. The aim of this study is to report clinical and radiological results from the Exeter V40 125 mm stem in performance of primary THA and revision THA. Materials and Methods: This study had a retrospective design. Insertion of 58 (24 primary, 34 revision) Exeter V40 125 mm stems was performed between 2015 and 2017. The minimum follow-up period was two years. Assessment of the Oxford hip score (OHS), EuroQol-5 Dimension (EQ-5D), and radiological follow-up was performed at one and two years. Results: In the primary group, the preoperative, mean OHS was 13.29. The mean OHS was 32.86 and 23.39 at one-year and two-year post-surgery, respectively. The mean EQ-5D-3L scores were at 0.14, 0.59, and 0.35, preoperatively, at one-year follow-up and two-year follow-up, respectively. In the revision group, the mean preoperative OHS was 19.41. The mean OHS was 30.55 and 26.05 at one-year and two-year post-surgery, respectively. The mean EQ-5D-3L scores were 0.33, 0.61, and 0.48 preoperatively, at one-year follow-up and two-year follow-up, respectively. No progressive or new radiolucent lines were observed around any stem at the time of the final follow-up in all patients in both groups. Conclusion: Encouraging results regarding use of Exeter V40 125 mm stems have been reported up to two years following surgery in primary and revision THA settings.

• 한국임상수의학회지
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• 제39권6호
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• pp.390-394
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• 2022

A 6-year-old, 36.5 kg castrated male Golden Retriever presented for revision surgery for left total hip replacement. The patient underwent removal of the cup and head implants due to unmanageable prosthetic hip dislocation, despite revision surgery. On physical examination, the dog showed persistent weight-bearing lameness after exercise of the left hindlimb with mild muscle atrophy. Radiographic examination revealed dorsolateral displacement of the femur with a remnant stem and bony proliferation around the cranial and caudal acetabulum rims. The surgical plan was to apply the dual mobility cup to increase the range of motion and jump distance to correct soft tissue elongation and laxity caused by a prolonged period of craniodorsal dislocation of the femur. The preparation of the acetabulum for cup fixation was performed with a 29-mm reamer, and the 29.5-mm outer shell was fixed with five 2.4-mm cortical screws. The head and medium neck of the dual-mobility system were placed on the cup, and the hip joint was reduced between the neck and stem. The dog exhibited slight weight bearing on a controlled leash walk the day after surgery. The patient was discharged 2 weeks postoperatively without any complications. Six months postoperatively, osseointegration and a well-positioned cup implant were observed, and the dog showed excellent limb function without hip dislocation until 18 months of phone call follow-up.

• 의료법학
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• 제16권1호
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• pp.191-219
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• 2015

줄기세포와 관련하여 우리나라에서는 배아 및 줄기세포 연구에 관한 입법으로서 생명윤리및안전에관한법률이 제정되어 있고, 줄기세포 치료제에 관해서는 약사법에 의해, 줄기세포 치료술에 관해서는 의료법 및 건강보험법 등의 관련 법령에 의해 규제되고 있다. 한편, 이러한 규제를 완화하고자 하는 법안 및 이를 전제한 정부의 투자활성화정책이 최근 제시되고 있다. 이것은 일본 아베내각 성립 후 아베노믹스(Abenomics)를 위한 3개의 축 중 하나로 '재생의료를 중심으로 한 의료산업'을 제시하며 각종 규제를 완화한 일본의 분위기와 어느 정도 닮아 있다. 일본은 '라이프 이노베이션', '신차원 일본 창조', '일본재흥전략'과 같은 다소 자극적인 정책 슬로건 하에서 줄기세포 연구 및 개발의 규제완화를 위하여 "재생의료를 국민이 선속하고 안전하게 받을 수 있도록 하기 위한 종합시책 추진에 관한 법률"등 통합적인 재생의료 관련 법률을 신속히 제정해 왔다. 본 논문은 이러한 배경 하에서 최근 일본의 줄기세포 재생의료 관련 정책 및 규제 동향을 검토하고 있다. 이는 우리나라 줄기세포 관련 규정의 재검토 및 최근 우리 정부의 규제완화 움직임의 타당성 여부를 판단함에 있어서 도움이 될 것으로 기대된다.

• Clinics in Shoulder and Elbow
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• 제21권2호
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• pp.105-110
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• 2018

Since the introduction of shoulder arthroplasty by Neer in 1974, the design of not only the glenoid component but also the humeral component used in shoulder arthroplasty has continually evolved. Changes to the design of the humeral component include a gradually disappearing proximal fin; diversified surface finishes (such as smooth, grit-blasted, and porous coating); a more contoured stem from the originally straight and cylindrical shape; and the use of press-fit uncemented fixation as opposed to cemented fixation. Despite the evolution of the humeral component for shoulder arthroplasty, however, stem-related complications are not uncommon. Examples of stem-related complications include intraoperative humeral fractures, stem loosening, periprosthetic fractures, and stress shielding. These become much more common in revision arthroplasty, where patients are associated with further complications such as surgical difficulty in extracting the humeral component, proximal metaphyseal bone loss due to stress shielding, intraoperative humeral shaft fractures, and incomplete cement removal. Physicians have made many attempts to reduce these complications by shortening the stem of the humeral component. In this review, we will discuss some of the limitations of long-stem humeral components, the feasibility of replacing them with short-stem humeral components, and the clinical outcomes associated with short-stemmed humeral components in shoulder arthroplasty.

• Hip & pelvis
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• 제30권4호
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• pp.210-218
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• 2018

Purpose: This is a report on the outcomes associated with a consecutive series of 1,000 cementless hip arthroplasties utilizing the $Bencox^{(R)}$ hip stem-the first Korean-developed hip prosthesis. Materials and Methods: A consecutive series of 1,000 hip arthroplasties using the $Bencox^{(R)}$ hip stem were analyzed, starting from its initial release (September 2006) until June 2014. Patients in this consecutive series underwent surgery for fractures (n=552), arthritis (n=155), avascular necrosis (n=209), and revisions (n=84). Of these 1,000 cases, patients with a minimum follow-up of at least 1 year (n=616) were retrospectively analyzed for radiographic and clinical outcomes (i.e., Harris hip score). The stability of the prosthesis was evaluated by examining subsidence. Results: During the follow-up period (mean follow-up period of 54.8 months), there were 2 cases requiring revision of the femoral stem-both were caused by periprosthetic fractures and neither involved stem loosening. The mean Harris hip score during follow-up was 95.5. Bone ongrowth occurred in 95% of patients; no cases of subsidence or aseptic loosening of the stem were detected, and no cases of postoperative complications such as ceramic breakage were observed. Conclusion: Clinical and radiographic evaluations of hip arthroplasty using the $Bencox^{(R)}$ hip stem revealed excellent outcomes with an average of 54.8 month follow-up in a consecutive series of 1,000 cases.

• Clinics in Shoulder and Elbow
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• 제26권1호
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• pp.93-106
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• 2023

Reverse total shoulder arthroplasty (RTSA) emerged as a new concept of arthroplasty that does not restore normal anatomy but does restore function. It enables the function of the torn rotator cuff to be performed by the deltoid and shows encouraging clinical outcomes. Since its introduction, various modifications have been designed to improve the outcome of the RTSA. From the original cemented baseplate with peg or keel, a cementless baseplate was designed that could be fixed with central and peripheral screws. In addition, a modular-type glenoid component enabled easier revision options. For the humeral component, the initial design was an inlay type of long stem with cemented fixation. However, loss of bone stock from the cemented stem hindered revision surgery. Therefore, a cementless design was introduced with a firm metaphyseal fixation. Furthermore, to prevent complications such as scapular notching, the concept of lateralization emerged. Lateralization helped to maintain normal shoulder contour and better rotator cuff function for improved external/internal rotation power, but excessive lateralization yielded problems such as subacromial notching. Therefore, for patients with pseudoparalysis or with risk of subacromial notching, a medial eccentric tray option can be used for distalization and reduced lateralization of the center of rotation. In summary, it is important that surgeons understand the characteristics of each implant in the various options for RTSA. Furthermore, through preoperative evaluation of patients, surgeons can choose the implant option that will lead to the best outcomes after RTSA.

• 한국식품위생안전성학회지
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• 제34권1호
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• pp.87-93
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• 2019

국제식퓸규격위원회(Codex Alimentarius Commission, CAC)는 2007년에 식품분류 개정작업에 착수하여 현재 대부분의 식품군에 대한 개정을 완료한 상태이다. 채소류의 경우 개정작업이 2014년에 시작됐으며 2017년에 $40^{th}$ CAC에 의해 개정안이 채택되었다. 여기에서는 식품 안전 규제를 비롯해 다양한 식품분야에서 활용될 수 있도록 채소류에 대한 CAC(코덱스) 식품분류 개정 내용을 소개하였다. 그 내용을 간략히 보면 코덱스는 채소류를 다음과 같이 10개의 그룹으로 분류하였다: bulb vegetables (Group 009), Brassica vegetables (except Brassica leafy vegetables) (Group 010), fruiting vegetables, Cucurbits (Group 011), fruiting vegetables, other than Cucurbits (Group 012), leafy vegetables (including Brassica leafy vegetables) (Group 013), legume vegetables (Group 014), pulses (Group 015), root and tuber vegetables (Group 016), stalk and stem vegetables (Group 017), edible fungi (Group 018). 또한 이들 그룹 안에는 subgroup을 두어 채소류는 총 33개의 subgroup으로 분류되고 현재 총 430개의 채소종류에 commodity code가 부여되어 있다. 국내 식품의약품안전처는 채소류와 마찬가지로 서류, 두류, 버섯류를 대분류로 하여 이들을 채소류에 포함시키지 않고 있다. 또한 채소류를 6개의 소분류인 결구 엽채류, 엽채류, 엽경채류, 근채류, 박과 과채류, 박과 이외 과채류로 세분화하고 있다. 이와 같이 코덱스와 국내의 식품분류에 차이가 있으므로 코덱스 식품분류를 활용하는 데 주의가 요구된다.

• 대한정형외과학회지
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• 제56권3호
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• pp.200-207
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• 2021

대퇴 삽입물 주위 골절은 고관절 치환술 후 발생하는 가장 치료하기 어려운 합병증 중 하나이며, 만족스러운 치료 결과를 얻으려면 면밀한 임상 및 방사선 사진 평가, 정확한 분류 및 치료 원칙에 대한 이해가 필수적이다. Vancouver 분류 시스템은 이러한 삽입물 주위 골절의 치료를 계획하기 위한 간단하고 효과적인 방법이다. 대퇴 스템이 안정된 골절은 견고한 내고정으로 효과적으로 치료할 수 있지만 대퇴 스템 해리가 동반된 경우 삽입물 주위 대퇴 골절은 재치환술이 필요하다. 고관절 치환술 후 발생할 수 있는 삽입물 주위 대퇴 골절 환자의 치료 원리와 대퇴 스템의 안정성을 평가하는 방법에 대해 설명하고자 한다.