이 작품은 RISystem AG, 다보스, 스위스에 의해 지원 되었다.

모든 실험 동물의 사용에 대 한 건강의 국가 학회 지침에 따라 수행한 과정과 기관 지침 (Landesamt에 Verbraucherschutz, Zentralstelle Amtstierärztlicher Dienst, 자르브뤼켄, 따라 독일)입니다.
1입니다. 수술 및 임 플 란 트의 준비
<ol><li>Microsurgical 악기 상자에서 메스 블레이드 (크기 15) 작은 면봉, 괜 찮 아 요 집게, 27 G 니 들, 비 resorbable 5-0 봉합가 위, 바늘 홀더를 선택 합니다.</li>
	<li>가이드 와이어 (0.3/0.2 m m 직경, 10 cm 길이), 중심 드릴 비트 (0.5 m m 직경) 및 (그림 1, 참조 테이블의 재료) 핸드 드릴 intramedullary 나사를 풀으십시오. 참고: intramedullary 나사 (0.5 m m 직경, 17.2 m m 길이) 대 퇴 골에 역행 주입을 위한 의학 급료 스테인리스의 이루어집니다. 나사 (0.2 m m, 0.4 m m 길이) 코를 가진 인접 스레드 (0.5 m m, 4 m m 길이) 팁과 원심 원뿔 모양 머리 (직경 0.8 m m, 0.9 m m 길이) 축 및 회전 안정성 골절 압축을 달성 하는 있다.</li>
	<li>임 플 란 트 및 5 분 동안 소독 솔루션 (96% 알코올)를 모든 수술 기구를 노출 시킵니다 또는 소독 (스팀 살 균, 130 ° C, 25 분). 소독, 살 균 후 작업 헝겊에 악기를 놓습니다. 작업 천으로 직접 작은 동물성 가동 테이블에 인접 한 위치입니다.</li>
</ol>2. 동물, 마 취 및 진통
<ol><li>나이, 긴장과 해결은 연구 질문에 따라 마우스의 섹스를 선택 합니다. 참고:이 연구에 대 한 12에 14-주-오래 된 남성 CD-1 마우스 사용 되었다. Intramedullary 나사를 사용 하 여 적절 한 몸 무게는 25-35 g 사이 이다.</li>
	<li>15 mg/kg xylazine 및 75 mg/kg 케 타 민의 복 주사와 마우스 anesthetize 발가락 핀치 여는 anesthetization를 확인 합니다. 마 취 동안 건조에서 동물 들의 눈을 보호 하기 위해 눈 윤 활 유를 적용 합니다. 마 취의 유도, 후 일정 체온을 유지 하는 열 라디에이터에서 마우스를 놓습니다. 절차 동안, 동물 마 취의 적절 한 평면 되도록 반복된 발가락 스푼으로 감시 되었다.</li>
	<li>하루에 1에서 수술 전에 수술 후 3 일까지 진통에 대 한 tramadol-염 식 수 (1.0 mg/mL)에 적용 됩니다. 참고: 진통 및 감염 예방 해야 국가와 기관 각각 지침과 일치 하 여 실험 수행 되어야 하는.</li>
</ol>3. 수술 및 Intramedullary 나사 주입
<ol><li>수술 하기 전에 전체 오른쪽 뒷 다리를 면도 하 고 depilatory 크림을 적용 합니다. 5 분 후 크림을 제거 하 고 물으로 다리를 청소 합니다. 그런 다음, 96% 알코올 소독 솔루션 적용. 완전 한 무 균 상태를 보장 하기 위해 알코올에 Betadine 또는 액체를 추가할 수 있습니다.</li>
	<li>무 균 조건 하에서 작은 동물성 가동 테이블에 부정사 위치에 마우스를 놓습니다. 앞쪽 무릎의 condyles 접근 수 있도록 오른쪽 무릎을 구 부. 메스 블레이드를 사용 하 여 오른쪽 무릎에 5mm 중간 parapatellar 절 개를 수행 합니다.</li>
	<li>메스 칼 날과 면봉으로 신중 하 게 슬 개 골 인 대를 동원. 그런 다음, 옆으로 대 퇴 골의 intercondylar 노치 노출 미세 집게와 슬 개 골을 이동 합니다.</li>
	<li>두 condyles 사이의 대 퇴 골의 중간에 정확 하 게 intercondylar 노치를 엽니다. 드릴 구멍 깊이 1.0 m m를 초과 하지 않도록 확인 합니다.<ol>
<li>느린 속도 ventrally 드릴 비트 및 핸드 드릴 (그림 1 c 와 D, 그림 2)을 중심으로 0.5 m m를 사용 하 여 대 퇴 골 축에 45 ° 오프셋에서 드릴링 수동 시작 합니다. 드릴링, 하는 동안 지속적으로 각도 0 ° 오프셋 (대 퇴 골 뼈 축 병렬)를 감소. 드릴링 1.0 m m의 깊이 도달 하면 중지 합니다.</li>
	</ol>
</li>
	<li>Intercondylar 노치에서 뼈를 연 후 대 퇴 골의 전체 길이 걸쳐 사용 intramedullary 구멍에 27g 바늘을 삽입 합니다. 27 G 바늘의 회전 동작을 통해 수동으로 대 퇴 골의 intramedullary 구멍 묶음 큰 trochanter에 외피 뼈 proximally 꿰뚫기 위하여 앞으로 바늘을 밀어.</li>
	<li>27 G 바늘을 제거 하 고 대 퇴 골의 원심 부분을 통해 가이드 와이어를 적용.<ol>
<li>피부 절 개를 메스 칼 날 (크기 15) proximally 가이드를 통해 만들고 가이드 와이어의 두 끝 다 밖에 서 때까지 가이드 와이어를 앞으로 밀어. 장소에 가이드 와이어를 계속 해야 합니다.</li>
	</ol>
</li>
	<li>단두대를 사용 하 여 정의 된 폐쇄 골절을 만듭니다.<ol>
<li>단두대 아래 오른쪽 다리와 가로 위치에 마우스를 놓습니다. 대 퇴 골의 diaphyseal 부분 단두대 중앙 배치는 다는 것을 확인 하십시오.</li>
		<li>25.5 cm의 정의 된 거리에서 (200 g) 무게를 드롭.</li>
	</ol>
</li>
	<li>X 선 장치를 사용 하 여 가이드 와이어 (그림 3)의 위치 뿐만 아니라 골절 구성 및 골절 위치 제어 ( 재료의 표참조).</li>
	<li>0.2 m m 가이드 와이어 선단부에 코를 가진 intramedullary 나사를 연결 하 고 지속적인 압력, 및 시계 방향으로 회전에서 대 퇴 골에 삽입.<ol>
<li>드라이브 샤프트 충분 한 토크를 달성 하는 경우의 전단.</li>
		<li>Proximally 가이드 와이어를 제거 합니다.</li>
	</ol>
</li>
	<li>슬 개 골 위치를 변경 하 고 슬 개 골 힘 줄 근육에 5-0 합성, monofilament, nonabsorbable 폴 리 프로필 렌 봉합 사를 사용 하 여 하나의 단일 봉합으로 해결. 같은 재료와 크기의 단일 봉합을 사용 하 여 상처를 닫습니다. 조각과 방사선학 x 선 장치를 사용 하 여 나사 위치의 감소를 제어 ( 재료의 표참조).</li>
	<li>그들은 마 취에서 회복 될 때까지 열 라디에이터에서 동물을 유지. 두지 마십시오 동물 무인 그들은 복 부 recumbency을 유지 하기 위해 충분 한 의식 회복 할 때까지. 동물 시설에서 단일 케이지를 동물을 반환 합니다. 반환 하지 않습니다 동물 다른 동물의 회사를 첫 24 시간 동안 그들은 완전히 마 취에서 회복 하는 경우에.</li>
	<li>동물을 신중 하 게 매일 모니터링 합니다. 수술 후 무 통 1.0 mg/mL의 복용량과 식 수에 tramadol-염 산을 사용 하 여 첫 3 일 동안 유지 합니다. 발성, 쉼 없는, 이동성, 신랑에 게 실패, 비정상적인 자세, 그리고 주변에 정상적인 관심의 부족의 부족에 의해 표시 된 경우, 수술 후 4 일에 동물 여전히 통증의 증거를 보여 진통을 계속 합니다. 동물 때 진통 종료 고통-무료.</li>
	<li>실험의 끝에 바르의 과다에 의해 동물을 안락사.</li>
</ol>

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저자 들은 아무 경쟁 금융 관심사 선언 합니다.

수술의 중요 한 단계는의 리밍 뼈 축에 평행한 바늘의 최적의 방향으로 intercondylar 노치에 대 퇴 골 condyles 중간 나사 이식에 대 한 올바른 진입점을 찾을 수 있는 intramedullary 캐비티입니다. 잘못 된 항목 위치를 방지 하려면 최적의 보기 달성 될 때까지 외과 의사 노치를 준비 해야 한다. 리밍 동안 방향 제어, 쥐의 대 퇴 골 안정적인 위치에 손가락으로 개최 한다. 더 중요 한 단계는 대 퇴 골에 나사?...

뼈 치유 연구 생쥐에서 항 체와 유전자 조작 동물의 광범위 한 스펙트럼 때문에 큰 수요에 있다. 이러한 사실을 뼈1치유의 분자 메커니즘 연구를 허용 합니다. 지난 몇 년 동안, 다른 뼈 모델 마우스 되었습니다 치유 개발2. 이 모델은 오픈 모델, 어떤 뼈는 osteotomized 오픈 측면 수술 방법을 사용 하 고 닫힌된 모델, 뼈 골절은 골절 모델 Bonnares 및 아인혼3도입으로 나눌 수 있습니다. 이 기술을 사용 하 여, 표준화 된 가로 골절 제작 하실 수 있습니다 3-포인트 절곡 장치 그리고 intramedullary 임 플 란 트를 최소 침 습 기술 주요 연 조직 외상을 피하에 작은 중간 parapatellar 절 개를 통해 삽입 될 수 있다.
Intramedullary 나사는 쥐에 폐쇄 골절 안정화를 위해 적용할 수 있습니다. 나사 축 회전 안정성을 제공합니다. 이 인접 스레드 및 원심 머리4를 통해 골절 압축에 의해 이루어집니다. 스크류의 더 이점은 간단한 수술 기법, invasivity, 낮은 저급 이식 무게와, 가장 주목할만 하 게, 더 높은 안정성 표준된 제어 biomechanical 조건을 다른 intramedullary에 비해 제공 하 5이 식은. 사실, 가장 폐쇄 골절 모델에서 조각을 회전 및 축 안정성의 완전 한 부족 및 핀의 높은 위험 관련 된 간단한 핀에 의해서만 안정 하 고 전위 골절. 이 현저 하 게 지연 치유 또는 비-연합 형성 발생할 수 있습니다 치유 과정을 좌우할 수 있다.
그것은 잘 알려진 안정성 골절 고정을 치유 과정6,7에 엄청난 영향을가지고. 골절 간격에 micromovements 수 있습니다, 덜 엄격한 고정 결과 endochondral 치유 하는 동안 높은 경직 된 고정 intramembranous 치료 결과. Intramedullary 나사와 골절의 안정화 주로 endochondral 치료 많은 양의 굳은 살 조직, 특히 골절 치유의 2 주 후 표시 됩니다. 굳은 살 조직 많은 양의 수확을 다른 기술로 여러 매개 변수 분석을 수 있습니다.
여기, 우리는 설계 및 intramedullary 나사 마우스, 뿐만 아니라 그것의 이점 및 단점 정상적인 endochondral 뼈 치유에 대 한 실험 연구에의 응용 프로그램에 보고합니다.

<table><tbody><tr><td>Mouse Screw</td><td>RISystem AG</td><td>221,100</td><td></td></tr><tr><td>Guide wire</td><td>RISystem AG</td><td>521,100</td><td></td></tr><tr><td>Centering bit</td><td>RISystem AG</td><td>590,205</td><td></td></tr><tr><td>Hand drill</td><td>RISystem AG</td><td>390,130</td><td></td></tr><tr><td>Cotton-Swab (150 mm, small head)</td><td>Fink Walter GmbH</td><td>8822428</td><td></td></tr><tr><td>Suture (5-0 Prolene)</td><td>Ethicon</td><td>8614H</td><td></td></tr><tr><td>Forceps</td><td>Braun Aesculap AG &amp;amp;CoKG</td><td>BD520R</td><td></td></tr><tr><td>Scissors</td><td>Braun Aesculap AG &amp;amp;CoKG</td><td>BC100R</td><td></td></tr><tr><td>Needle holder</td><td>Braun Aesculap AG &amp;amp;CoKG</td><td>BM024R</td><td></td></tr><tr><td>27 G needle</td><td>Braun Melsungen AG</td><td>9186182</td><td></td></tr><tr><td>Scalpel blade size 15</td><td>Braun Aesculap AG &amp;amp;CoKG</td><td>16600525</td><td></td></tr><tr><td>Heat radiator</td><td>Sanitas</td><td>605.25</td><td></td></tr><tr><td>Depilatory cream</td><td>Asid bonz GmbH</td><td>NDXZ10</td><td></td></tr><tr><td>Eye lubricant</td><td>Bayer Vital GmbH</td><td>2182442</td><td></td></tr><tr><td>Xylazine</td><td>Bayer Vital GmbH</td><td>1320422</td><td></td></tr><tr><td>Ketamine</td><td>Serumwerke Bernburg</td><td>7005294</td><td></td></tr><tr><td>Tramadol</td><td>Gr&amp;uuml;nenthal GmbH</td><td>2256241</td><td></td></tr><tr><td>Disinfection solution (SoftaseptN)</td><td>Braun Melsungen AG</td><td>8505018</td><td></td></tr><tr><td>CD-1 mice</td><td>Charles River</td><td>22</td><td></td></tr><tr><td>X-ray Device</td><td>Faxitron MX-20, Faxitron X-ray Corporation</td><td>2321A0988</td><td></td></tr><tr><td>Fracture device small</td><td>RISystem AG</td><td>891,100</td><td></td></tr></tbody></table>

a minimally invasive model to analyze endochondral fracture healing in mice under standardized biomechanical conditions

뼈 치료 모델은 골절 임상 골절 치료를 개선 하기 위해 치료의 복잡 한 메커니즘을 분석 하는 데 필요한. 지난 10 년 동안 정형 외과 연구에 마우스 모델의 증가 사용을 지적 했다, 대부분의 아마 마우스 모델 유전자 변형 종자 및 골절 치유의 분자 메커니즘의 분석에 대 한 특별 한 항 체의 많은 수를 제공 하기 때문에. 제어 하려면 biomechanical 조건, 잘 특징이 osteosynthesis 기법 또한 쥐에 필수입니다. 여기, 우리는 쥐의 대 퇴 골 골절을 안정화 설계 및 닫힌된 뼈 치유 모델의 사용에 보고. 의학 급료 스테인리스 intramedullary 나사 골절 압축을 통해 축 및 회전 안정성의 완전 한 부족을 보여 주로 사용된 간단한 intramedullary 핀에 비해 축 및 회전 안정성을 제공 합니다. Intramedullary 나사에 의해 달성 안정성 endochondral 치유의 분석을 수 있습니다. 굳은 살 조직, 나사, 안정화 후 받은 많은 양의 수확 생 화 학적 및 분자 분석에 대 한 조직에 이상적인 조건을 제공 합니다. 나사를 사용 하 여의 더 이점은 유도 하는 부드러운 조직에 손상 없이 나사 침 습 기법으로 대 퇴 골에 삽입할 수 있는 사실 이다. 결론적으로, 나사 폐쇄 골절 치유 모델을 제공 하는 표준화 된 biomechanical 조건에에서 이상적으로 사용 될 수 있는 독특한 이식입니다.

피부 절 개 상처 폐쇄 하에서 동작 시간은 20 분 이었다. 스테레오 현미경 없이 수술을 수행할 수 있습니다. Postoperatively, 동물 매일 감시 되었다. 동물의이 기간 후 통증의 증거를 보여주 때문에 수술 후 진통 2 일 후 종료 되었습니다. 동물 수술 후 2 일 이내에 정상적인 체중 부하를 또한 보여주었다. 상처 감염 되지 전체 관찰 기간 동안 관찰 되었다.
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A Minimally Invasive Model to Analyze Endochondral Fracture Healing in Mice Under Standardized Biomechanical Conditions

이 프로토콜 분석 endochondral 뼈 쥐에서 치유 하는 데 사용할 수 있습니다 대 퇴 골 골절의 표준화 된 안정화를 위한 intramedullary 나사를 사용 하 여 최소 침 습 osteosynthesis 기술을 설명 합니다.

Endochondral 골절 표준화 된 Biomechanical 조건 하에서 쥐에서 치유를 분석 하는 최소 침 습 모델

Bone healing models are necessary to analyze the complex mechanisms of fracture healing to improve clinical fracture treatment. During the last decade, an ...

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JoVE Journal

Medicine

8.2K 조회수.  Saarland University. 이 프로토콜 분석 endochondral 뼈 쥐에서 치유 하는 데 사용할 수 있습니다 대 퇴 골 골절의 표준화 된 안정화를 위한 intramedullary 나사를 사용 하 여 최소 침 습 osteosynthesis 기술을 설명 합니다.

비디오: A Minimally Invasive Model to Analyze Endochondral Fracture Healing in Mice Under Standardized Biomechanical Conditions

A Simple Critical-sized Femoral Defect Model in Mice

While bone has a remarkable capacity for regeneration, serious bone trauma often results in damage that does not properly heal. In fact, one tenth of all limb bone fractures fail to heal completely due to the extent of the trauma, disease, or age of the patient. Our ability to improve bone regenerative strategies is critically dependent on the ability to mimic serious bone trauma in test animals, but the generation and stabilization of large bone lesions is technically challenging. In most cases, serious long bone trauma is mimicked experimentally by establishing a defect that will not naturally heal. This is achieved by complete removal of a bone segment that is larger than 1.5 times the diameter of the bone cross-section. The bone is then stabilized with a metal implant to maintain proper orientation of the fracture edges and allow for mobility. 
Due to their small size and the fragility of their long bones, establishment of such lesions in mice are beyond the capabilities of most research groups. As such, long bone defect models are confined to rats and larger animals. Nevertheless, mice afford significant research advantages in that they can be genetically modified and bred as immune-compromised strains that do not reject human cells and tissue.
Herein, we demonstrate a technique that facilitates the generation of a segmental defect in mouse femora using standard laboratory and veterinary equipment. With practice, fabrication of the fixation device and surgical implantation is feasible for the majority of trained veterinarians and animal research personnel. Using example data, we also provide methodologies for the quantitative analysis of bone healing for the model.

Animal models are frequently employed to mimic serious bone injury in biomedical research. Due to their small size, establishment of stabilized bone lesions in mice are beyond the capabilities of most research groups. Herein, we describe a simple method for establishing and analyzing experimental femoral defects in mice.

마우스의 간단한 임계 크기의 대퇴 결함 모델

While bone has a remarkable capacity for regeneration, serious bone trauma often results in damage that does not properly heal. In fact, one tenth of all ...

연구

의학

Establishment of a Segmental Femoral Critical-size Defect Model in Mice Stabilized by Plate Osteosynthesis

The use of tissue-engineered bone constructs is an appealing strategy to overcome drawbacks of autografts for the treatment of massive bone defects. As a model organism, the mouse has already been widely used in bone-related research. Large diaphyseal bone defect models in mice, however, are sparse and often use bone fixation which fills the bone marrow cavity and does not provide optimal mechanical stability. The objectives of the current study were to develop a critical-size, segmental, femoral defect in nude mice. A 3.5-mm mid-diaphyseal femoral ostectomy (approximately 25% of the femur length) was performed using a dedicated jig, and was stabilized with an anterior located locking plate and 4 locking screws. The bone defect was subsequently either left empty or filled with a bone substitute (syngenic bone graft or coralline scaffold). Bone healing was monitored noninvasively using radiography and in vivo micro-computed-tomography and was subsequently assessed by ex vivo micro-computed-tomography and undecalcified histology after animal sacrifice, 10 weeks postoperatively. The recovery of all mice was excellent, a full-weight-bearing was observed within one day following the surgical procedure. Furthermore, stable bone fixation and consistent fixation of the implanted materials were achieved in all animals tested throughout the study. When the bone defects were left empty, non-union was consistently obtained. In contrast, when the bone defects were filled with syngenic bone grafts, bone union was always observed. When the bone defects were filled with coralline scaffolds, newly-formed bone was observed in the interface between bone resection edges and the scaffold, as well as within a short distance within the scaffold. 
The present model describes a reproducible critical-size femoral defect stabilized by plate osteosynthesis with low morbidity in mice. The new load-bearing segmental bone defect model could be useful for studying the underlying mechanisms in bone regeneration pertinent to orthopaedic applications.

Although mouse models are invaluable tools for bone tissue engineering, models of long bone defects are sparse. This need motivated development of the present protocol which uses a locking plate with four screws and a dedicated jig to perform and stabilize a reproducible, femoral, critical-size defect with low morbidity.

마우스의 분절 대퇴 임계 크기 결함 모델의 설립은 플레이트 고정술에 의해 안정화

The use of tissue-engineered bone constructs is an appealing strategy to overcome drawbacks of autografts for the treatment of massive bone defects. As a ...

Real-time Visualization and Analysis of Chondrocyte Injury Due to Mechanical Loading in Fully Intact Murine Cartilage Explants

Homeostasis of articular cartilage depends on the viability of resident cells (chondrocytes). Unfortunately, mechanical trauma can induce widespread chondrocyte death, potentially leading to irreversible breakdown of the joint and the onset of osteoarthritis. Additionally, maintenance of chondrocyte viability is important in osteochondral graft procedures for optimal surgical outcomes. We present a method to assess the spatial extent of cell injury/death on the articular surface of intact murine synovial joints after application of controlled mechanical loads or impacts. This method can be used in comparative studies to investigate the effects of different mechanical loading regimens, different environmental conditions or genetic manipulations, as well as different stages of cartilage degeneration on short- and/or long-term vulnerability of in situ articular chondrocytes. The goal of the protocol introduced in the manuscript is to assess the spatial extent of cell injury/death on the articular surface of murine synovial joints. Importantly, this method enables testing on fully intact cartilage without compromising native boundary conditions. Moreover, it allows for real-time visualization of vitally stained articular chondrocytes and single image-based analysis of cell injury induced by application of controlled static and impact loading regimens. Our representative results demonstrate that in healthy cartilage explants, the spatial extent of cell injury depends sensitively on load magnitude and impact intensity. Our method can be easily adapted to investigate the effects of different mechanical loading regimens, different environmental conditions or different genetic manipulations on the mechanical vulnerability of in situ articular chondrocytes.

We present a method to assess the spatial extent of cell injury/death on the articular surface of intact murine joints after application of controlled mechanical loads or impacts. This method can be used to investigate how osteoarthritis, genetic factors and/or different loading regimens affect the vulnerability of in situ chondrocytes.

실시간 시각화 및 Chondrocyte 부상 때문에 완전히 그대로 Murine 연골 Explants 기계적 부하의 분석

Homeostasis of articular cartilage depends on the viability of resident cells (chondrocytes). Unfortunately, mechanical trauma can induce widespread ...

생체공학

An Intramedullary Locking Nail for Standardized Fixation of Femur Osteotomies to Analyze Normal and Defective Bone Healing in Mice

Bone healing models are essential to the development of new therapeutic strategies for clinical fracture treatment. Furthermore, mouse models are becoming more commonly used in trauma research. They offer a large number of mutant strains and antibodies for the analysis of the molecular mechanisms behind the highly differentiated process of bone healing. To control the biomechanical environment, standardized and well-characterized osteosynthesis techniques are mandatory in mice. Here, we report on the design and use of an intramedullary nail to stabilize open femur osteotomies in mice. The nail, made of medical-grade stainless steel, provides high axial and rotational stiffness. The implant further allows the creation of defined, constant osteotomy gap sizes from 0.00 mm to 2.00 mm. Intramedullary locking nail stabilization of femur osteotomies with gap sizes of 0.00 mm and 0.25 mm result in adequate bone healing through endochondral and intramembranous ossification. Stabilization of femur osteotomies with a gap size of 2.00 mm results in atrophic non-union. Thus, the intramedullary locking nail can be used in healing and non-healing models. A further advantage of the use of the nail compared to other open bone healing models is the possibility to adequately fix bone substitutes and scaffolds in order to study the process of osseous integration. A disadvantage of the use of the intramedullary nail is the more invasive surgical procedure, inherent to all open procedures compared to closed models. A further disadvantage may be the induction of some damage to the intramedullary cavity, inherent to all intramedullary stabilization techniques compared to extramedullary stabilization procedures.

This protocol describes an osteosynthesis technique using an intramedullary locking nail for standardized fixation of femur osteotomies, which can be used to analyze normal and defective bone healing in mice.

대퇴골 절골술의 표준화 된 고정을위한 골수 내 잠금 네일은 마우스에 정상 및 결함 뼈 치유를 분석하기

Bone healing models are essential to the development of new therapeutic strategies for clinical fracture treatment. Furthermore, mouse models are becoming ...

In Vivo Evaluation of Fracture Callus Development During Bone Healing in Mice Using an MRI-compatible Osteosynthesis Device for the Mouse Femur

Endochondral fracture healing is a complex process involving the development of fibrous, cartilaginous, and osseous tissue in the fracture callus. The amount of the different tissues in the callus provides important information on the fracture healing progress. Available in vivo techniques to longitudinally monitor the callus tissue development in preclinical fracture-healing studies using small animals include digital radiography and &#181;CT imaging. However, both techniques are only able to distinguish between mineralized and non-mineralized tissue. Consequently, it is impossible to discriminate cartilage from fibrous tissue. In contrast, magnetic resonance imaging (MRI) visualizes anatomical structures based on their water content and might therefore be able to noninvasively identify soft tissue and cartilage in the fracture callus. Here, we report the use of an MRI-compatible external fixator for the mouse femur to allow MRI scans during bone regeneration in mice. The experiments demonstrated that the fixator and a custom-made mounting device allow repetitive MRI scans, thus enabling longitudinal analysis of fracture-callus tissue development.

In Vivo Evaluation of Fracture Callus Development During Bone Healing in Mice Using an MRI-compatible Osteosynthesis Device for the Mouse Femur

The evaluation of tissue development in the fracture callus during endochondral bone healing is essential to monitor the healing process. Here, we report the use of a magnetic resonance imaging (MRI)-compatible external fixator for the mouse femur to allow MRI scans during bone regeneration in mice.

Vivo에서 골절 뼈 쥐 마우스 대 퇴 골에 대 한 MRI-호환 Osteosynthesis 장치를 사용 하 여 치료 기간 동안 굳은 살 개발의 평가

Endochondral fracture healing is a complex process involving the development of fibrous, cartilaginous, and osseous tissue in the fracture callus. The ...

A Mouse Model of Orthopedic Surgery to Study Postoperative Cognitive Dysfunction and Tissue Regeneration

Surgery is commonly used to improve and maintain quality of life. Unfortunately, in vulnerable patients such as the elderly, complications may occur and significantly diminish the outcome. Indeed, after routine orthopedic surgery to repair a fracture, as many as 50% of elderly patients suffer from neurologic complications like delirium. Also, the capacity to heal and regenerate tissue after surgery decreases with age, and can impact the quality of fracture repair and even osseous integration of implants. Thus, a better understanding of mechanisms that drive these age-dependent changes could provide strategic targets to minimize risk for such complications and optimize outcomes. Here, we introduce a clinically relevant mouse model of tibial fracture. The postoperative changes in these mice mimic some of the cognitive impairments commonly observed after routine orthopedic surgery in humans. Briefly, an incision is performed in the right hind limb under strictly aseptic conditions. Muscles are disassociated, and a 0.38-mm stainless steel pin is inserted into the upper crest of the tibia, inside the intramedullary canal. Osteotomy is then performed, and the wound is stapled. We have used this model to investigate the effects of surgical trauma on postoperative neuroinflammation and behavioral changes. By applying this fracture model in combination with parabiosis, a surgical model in which 2 mice are anastomosed, we have studied cells and secreted factors that systemically rejuvenate organ function and tissue regeneration after injury. By following our step-by-step protocol, these models can be reproduced with high fidelity, and can be adapted to interrogate many biologic pathways that are altered by surgical trauma.

This protocol describes a mouse model of orthopedic surgery that has been used to study mechanisms of postoperative neuroinflammation and behavioral changes, and when combined with parabiosis, to study tissue regeneration during aging.

정형 외과 수술 후 인지 기능 장애 및 조직 재생 연구의 마우스 모델

Surgery is commonly used to improve and maintain quality of life. Unfortunately, in vulnerable patients such as the elderly, complications may occur and ...

The Generation of Closed Femoral Fractures in Mice: A Model to Study Bone Healing

Bone fractures impose a tremendous socio-economic burden on patients, in addition to significantly affecting their quality of life. Therapeutic strategies that promote efficient bone healing are non-existent and in high demand. Effective and reproducible animal models of fractures healing are needed to understand the complex biological processes associated with bone regeneration. Many animal models of fracture healing have been generated over the years; however, murine fracture models have recently emerged as powerful tools to study bone healing. A variety of open and closed models have been developed, but the closed femoral fracture model stands out as a simple method for generating rapid and reproducible results in a physiologically relevant manner. The goal of this surgical protocol is to generate unilateral closed femoral fractures in mice and facilitate a post-fracture stabilization of the femur by inserting an intramedullary steel rod. Although devices such as a nail or a screw offer greater axial and rotational stability, the use of an intramedullary rod provides a sufficient stabilization for consistent healing outcomes without producing new defects in the bone tissue or damaging nearby soft tissue. Radiographic imaging is used to monitor the progression of callus formation, bony union, and subsequent remodeling of the bony callus. Bone healing outcomes are typically associated with the strength of the healed bone and measured with torsional testing. Still, understanding the early cellular and molecular events associated with fracture repair is critical in the study of bone tissue regeneration. The closed femoral fracture model in mice with intramedullary fixation serves as an attractive platform to study bone fracture healing and evaluate therapeutic strategies to accelerate healing.

The murine closed femoral fracture model is a powerful platform to study fracture healing and novel therapeutic strategies to accelerate bone regeneration. The goal of this surgical protocol is to generate unilateral closed femoral fractures in mice using an intramedullary steel rod to stabilize the femur.

Bone fractures impose a tremendous socio-economic burden on patients, in addition to significantly affecting their quality of life. Therapeutic strategies ...

Transverse Fracture of the Mouse Femur with Stabilizing Pin

Fracture repair is an essential function of the skeleton that cannot be reliably modeled in vitro. A mouse injury model is an efficient approach to test whether a gene, gene product or drug influences bone repair because murine bones recapitulate the stages observed during human fracture healing. When a mouse or human breaks a bone, an inflammatory response is initiated, and the periosteum, a stem cell niche surrounding the bone itself, is activated and expands. Cells residing in the periosteum then differentiate to form a vascularized soft callus. The transition from the soft callus to a hard callus occurs as the recruited skeletal progenitor cells differentiate into mineralizing cells, and the bridging of the fractured ends results in the bone union. The mineralized callus then undergoes remodeling to restore the original shape and structure of the healed bone. Fracture healing has been studied in mice using various injury models. Still, the best way to recapitulate this entire biological process is to break through the cross-section of a long bone that encompasses both cortices. This protocol describes how a stabilized, transverse femur fracture can be safely performed to assess healing in adult mice. A surgical protocol including detailed harvesting and imaging techniques to characterize the different stages of fracture healing is also provided.

This protocol describes a method to perform fractures on adult mice and monitor the healing process.

안정화 핀을 가진 마우스 대퇴골의 횡단 골절

Fracture repair is an essential function of the skeleton that cannot be reliably modeled in vitro. A mouse injury model is an efficient approach to test ...

생물학

Establishing a Diaphyseal Femur Fracture Model in Mice

Bones have a significant regenerative capacity. However, fracture healing is a complex process, and depending on the severity of the lesions and the age and overall health status of the patient, failures can occur, leading to delayed union or nonunion. Due to the increasing number of fractures resulting from high-energy trauma and aging, the development of innovative therapeutic strategies to improve bone repair based on the combination of skeletal/mesenchymal stem/stromal cells and biomimetic biomaterials is urgently needed. To this end, the use of reliable animal models is fundamental to better understanding the key cellular and molecular mechanisms that determine the healing outcomes. Of all the models, the mouse is the preferred research model because it offers a wide variety of transgenic strains and reagents for experimental analysis. However, the establishment of fractures in mice may be technically challenging due to their small size. Therefore, this article aims to demonstrate the procedures for the surgical establishment of a diaphyseal femur fracture in mice, which is stabilized with an intramedullary wire and resembles the most common bone repair process, through cartilaginous callus formation.

This protocol describes a surgical procedure for the establishment of a diaphyseal fracture in the femur of mice, which is stabilized with an intramedullary wire, for fracture healing studies.

마우스에서 Diaphyseal 대퇴골 골절 모델 확립

Bones have a significant regenerative capacity. However, fracture healing is a complex process, and depending on the severity of the lesions and the age ...

<meta charset="utf8"></head><body>생쥐의 뼈 수리를 위한 표준화된 하악 골절 프로토콜

Less-Invasive Technique for Non-stabilized Mandibular Fracture in Mouse Models

Non-stabilized fractures can be made at mandibular sites in mice, thus making it possible to analyze bone repair using an endochondral ossification mode. To most accurately reflect this process in vivo, it is necessary to have a standardized protocol to avoid excessive bone loss and soft tissue damage, particularly at the mandibular site, an anatomical site characterized by minimal access. To our knowledge, we describe for the first time a less-invasive protocol of non-stabilized mandibular fracture in mice. Adult mice are anesthetized with isoflurane and receive a preoperative dose of buprenorphine by subcutaneous injection. A submandibular approach is performed, with a skin incision made along the inferior border of the mandible. The masseter muscle is elevated in a subperiosteal plane along the mandibular ramus with a periosteal elevator. A vertical and complete fracture of the ramus is performed from the basilar border to the coronoid notch (between condylar and coronoid processes), using a piezoelectric bone surgery device under saline serum irrigation at the basilar edge and scissors to complete the fracture of the mandibular ramus. The skin approach is closed by silk sutures. This detailed procedure for non-stabilized mandibular fractures offers an efficient procedure allowing minimal bone loss and soft tissue damage. This technique ensures successful and consistent results to accurately reflect the process of endochondral bone repair in mouse models.

<meta charset="utf8"></head><body>Less-Invasive Technique for Non-stabilized Mandibular Fracture in Mouse Models

This protocol presents a comprehensive and efficient method for analyzing mandibular bone repair. We describe a reproducible technique for non-stabilized mandibular fracture in a mouse model, allowing analysis of the process of endochondral bone repair with minimal tissue damage and bone loss.

Non-stabilized fractures can be made at mandibular sites in mice, thus making it possible to analyze bone repair using an endochondral ossification mode. ...