وأيد هذا العمل من قبل مؤسسة AO (S-08-42G) وRISystem AG. نود أن نمد كبيرة جدا &quot;شكرا!&quot; إلى الفريق ستيفان زعيتر في في معهد أبحاث AO دافوس، سويسرا لكونها استيعاب ذلك في السماح لنا باستخدام مرافقها أو لتصوير هذا الإجراء الجراحي.

<ol>
	<li>Einhorn, T. A., Lane, J. M., Burstein, A. H., Kopman, C. R., Vigorita, V. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+healing+of+segmental+bone+defects+induced+by+demineralized+bone+matrix.+A+radiographic+and+biomechanical+study.">The healing of segmental bone defects induced by demineralized bone matrix. A radiographic and biomechanical study.</a> J Bone Joint Surg Am. 66, 274-279 (1984).</li><li>Feighan, J. E., Davy, D., Prewett, A. B., Stevenson, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+bone+by+a+demineralized+bone+matrix+gel:+a+study+in+a+rat+femoral+defect+model.">Induction of bone by a demineralized bone matrix gel: a study in a rat femoral defect model.</a> J Orthop Res. 13, 881-891 (1995).</li><li>Hunt, T. R., Schwappach, J. R., Anderson, H. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Healing+of+a+segmental+defect+in+the+rat+femur+with+use+of+an+extract+from+a+cultured+human+osteosarcoma+cell-line+(Saos-2).+A+preliminary+report.">Healing of a segmental defect in the rat femur with use of an extract from a cultured human osteosarcoma cell-line (Saos-2). A preliminary report.</a> J Bone Joint Surg Am. 78, 41-48 (1996).</li><li>Jazrawi, L. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bone+and+cartilage+formation+in+an+experimental+model+of+distraction+osteogenesis.">Bone and cartilage formation in an experimental model of distraction osteogenesis.</a> J Orthop Trauma. 12, 111-116 (1998).</li><li>Probst, A., Jansen, H., Ladas, A., Spiegel, H. U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Callus+formation+and+fixation+rigidity:+a+fracture+model+in+rats.">Callus formation and fixation rigidity: a fracture model in rats.</a> J Orthop Res. 17, 256-260 (1999).</li><li>Richards, M., Huibregtse, B. A., Caplan, A. I., Goulet, J. A., Goldstein, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Marrow-derived+progenitor+cell+injections+enhance+new+bone+formation+during+distraction.">Marrow-derived progenitor cell injections enhance new bone formation during distraction.</a> J Orthop Res. 17, 900-908 (1999).</li><li>Aro, H. T., Chao, E. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bone-healing+patterns+affected+by+loading,+fracture+fragment+stability,+fracture+type,+and+fracture+site+compression.">Bone-healing patterns affected by loading, fracture fragment stability, fracture type, and fracture site compression.</a> Clin Orthop Relat Res. , 8-17 (1993).</li><li>Augat, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shear+movement+at+the+fracture+site+delays+healing+in+a+diaphyseal+fracture+model.">Shear movement at the fracture site delays healing in a diaphyseal fracture model.</a> J Orthop Res. 21, 1011-1017 (2003).</li><li>Augat, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Local+tissue+properties+in+bone+healing:+influence+of+size+and+stability+of+the+osteotomy+gap.">Local tissue properties in bone healing: influence of size and stability of the osteotomy gap.</a> J Orthop Res. 16, 475-481 (1998).</li><li>Claes, L., Augat, P., Suger, G., Wilke, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influence+of+size+and+stability+of+the+osteotomy+gap+on+the+success+of+fracture+healing.">Influence of size and stability of the osteotomy gap on the success of fracture healing.</a> J Orthop Res. 15, 577-584 (1997).</li><li>Claes, L., Eckert-Hubner, K., Augat, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+fracture+gap+size+influences+the+local+vascularization+and+tissue+differentiation+in+callus+healing.">The fracture gap size influences the local vascularization and tissue differentiation in callus healing.</a> Langenbecks Arch Surg. 388, 316-322 (2003).</li><li>Duda, G. N., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Interfragmentary+motion+in+tibial+osteotomies+stabilized+with+ring+fixators.">Interfragmentary motion in tibial osteotomies stabilized with ring fixators.</a> Clin Orthop Relat Res. , 163-172 (2002).</li><li>Goodship, A. E., Watkins, P. E., Rigby, H. S., Kenwright, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+fixator+frame+stiffness+in+the+control+of+fracture+healing.+An+experimental+study.">The role of fixator frame stiffness in the control of fracture healing. An experimental study.</a> J Biomech. 26, 1027-1035 (1993).</li><li>Williams, E. A., Rand, J. A., An, K. N., Chao, E. Y., Kelly, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+early+healing+of+tibial+osteotomies+stabilized+by+one-plane+or+two-plane+external+fixation.">The early healing of tibial osteotomies stabilized by one-plane or two-plane external fixation.</a> J Bone Joint Surg Am. 69, 355-365 (1987).</li><li>Wu, J. J., Shyr, H. S., Chao, E. Y., Kelly, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+osteotomy+healing+under+external+fixation+devices+with+different+stiffness+characteristics.">Comparison of osteotomy healing under external fixation devices with different stiffness characteristics.</a> J Bone Joint Surg Am. 66, 1258-1264 (1984).</li><li>Harrison, L. J., Cunningham, J. L., Stromberg, L., Goodship, A. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Controlled+induction+of+a+pseudarthrosis:+a+study+using+a+rodent+model.">Controlled induction of a pseudarthrosis: a study using a rodent model.</a> J Orthop Trauma. 17, 11-21 (2003).</li><li>Kaspar, K., Schell, H., Toben, D., Matziolis, G., Bail, H. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+easily+reproducible+and+biomechanically+standardized+model+to+investigate+bone+healing+in+rats,+using+external+fixation.">An easily reproducible and biomechanically standardized model to investigate bone healing in rats, using external fixation.</a> Biomed Tech (Berl). 52, 383-390 (2007).</li><li>Mark, H., Bergholm, J., Nilsson, A., Rydevik, B., Stromberg, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+external+fixation+method+and+device+to+study+fracture+healing+in+rats.">An external fixation method and device to study fracture healing in rats.</a> Acta Orthop Scand. 74, 476-482 (2003).</li><li>Mark, H., Nilsson, A., Nannmark, U., Rydevik, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+fracture+fixation+stability+on+ossification+in+healing+fractures.">Effects of fracture fixation stability on ossification in healing fractures.</a> Clin Orthop Relat. Res. , 245-250 (2004).</li><li>Mark, H., Rydevik, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Torsional+stiffness+in+healing+fractures:+influence+of+ossification:+an+experimental+study+in+rats.">Torsional stiffness in healing fractures: influence of ossification: an experimental study in rats.</a> Acta Orthop. 76, 428-433 (2005).</li><li>McCann, R. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+osteoporosis+on+bone+mineral+density+and+fracture+repair+in+a+rat+femoral+fracture+model.">Effect of osteoporosis on bone mineral density and fracture repair in a rat femoral fracture model.</a> J Orthop Res. 26, 384-393 (2008).</li><li>Betz, O. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+percutaneous+gene+delivery+to+enhance+healing+of+segmental+bone+defects.">Direct percutaneous gene delivery to enhance healing of segmental bone defects.</a> J Bone Joint Surg Am. 88, 355-365 (2006).</li><li>Cullinane, D. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+a+neoarthrosis+by+precisely+controlled+motion+in+an+experimental+mid-femoral+defect.">Induction of a neoarthrosis by precisely controlled motion in an experimental mid-femoral defect.</a> J Orthop Res. 20, 579-586 (2002).</li><li>Dickson, G. R., Geddis, C., Fazzalari, N., Marsh, D., Parkinson, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microcomputed+tomography+imaging+in+a+rat+model+of+delayed+union/non-union+fracture.">Microcomputed tomography imaging in a rat model of delayed union/non-union fracture.</a> J Orthop Res. 26, 729-736 (2008).</li><li>Jager, M., Sager, M., Lensing-Hohn, S., Krauspe, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+critical+size+bony+defect+in+a+small+animal+for+bone+healing+studies+(II):+implant+evolution+and+surgical+technique+on+a+rat's+femur.">The critical size bony defect in a small animal for bone healing studies (II): implant evolution and surgical technique on a rat's femur.</a> Biomed Tech (Berl). 50, 137-142 (2005).</li><li>Betz, V. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Healing+of+segmental+bone+defects+by+direct+percutaneous+gene+delivery:+effect+of+vector+dose.">Healing of segmental bone defects by direct percutaneous gene delivery: effect of vector dose.</a> Hum Gene Ther. 18, 907-915 (2007).</li><li>Glatt, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ability+of+recombinant+human+bone+morphogenetic+protein+2+to+enhance+bone+healing+in+the+presence+of+tobramycin:+evaluation+in+a+rat+segmental+defect+model.">Ability of recombinant human bone morphogenetic protein 2 to enhance bone healing in the presence of tobramycin: evaluation in a rat segmental defect model.</a> J Orthop Trauma. 23, 693-701 (2009).</li><li>Willie, B., Adkins, K., Zheng, X., Simon, U., Claes, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical+characterization+of+external+fixator+stiffness+for+a+rat+femoral+fracture+model.">Mechanical characterization of external fixator stiffness for a rat femoral fracture model.</a> J Orthop Res. 27, 687-693 (2009).</li><li>Hess, T., Hopf, T., Fritsch, E., Mittelmeier, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparative+biomechanical+studies+of+conventional+and+self-tapping+cortical+bone+screws.">Comparative biomechanical studies of conventional and self-tapping cortical bone screws.</a> Z Orthop Ihre Grenzgeb. 129, 278-282 (1991).</li><li>Glatt, V., Evans, C. H., Matthys, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design,+characterisation+and+in+vivo+testing+of+a+new,+adjustable+stiffness,+external+fixator+for+the+rat+femur.">Design, characterisation and in vivo testing of a new, adjustable stiffness, external fixator for the rat femur.</a> Eur Cell Mater. 23, 289-298 (2012).</li><li>Glatt, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improved+healing+of+large+segmental+defects+in+the+rat+femur+by+reverse+dynamization+in+the+presence+of+bone+morphogenetic+protein-2.">Improved healing of large segmental defects in the rat femur by reverse dynamization in the presence of bone morphogenetic protein-2.</a> J Bone Joint Surg Am. 94, 2063-2073 (2012).</li></ol>

المؤلف رومانو ماتيز هو موظف من RISystem AG دافوس، سويسرا التي تنتج يزرع، وأدوات محددة الزرع والمواد الاستهلاكية المستخدمة في هذه المقالة. المؤلف فايدا جلات ليس لديه المصالح المالية المتنافسة.

الخطوات الأكثر أهمية من إجراء العمليات الجراحية لخلق خلل كبير العظام هي: 1) اختيار وزن الجسم المناسب من الفئران لتتناسب مع حجم التبعي الخارجي؛ 2) الحفاظ على بيئة معقمة أثناء الداخلي؛ و3) بعد بروتوكول الإجراء الجراحي. وكانت الأهداف ...

هناك عدد من الدراسات قد تحسنت فهمنا للآليات البيولوجية المشاركة في العظام إصلاح الأنسجة 1-6. وقد تم دراسة آثار الظروف الميكانيكية على إصلاح العظام مثل محوري، والقص والحركات interfragmentary (نظام الإدارة المالية المتكامل) على نطاق واسع 7-15. في السنوات القليلة الماضية، بدأت المزيد والمزيد من الدراسات تظهر واصفا تأثير البيئة الميكانيكية على التئام العظام باستخدام الكسر، العظم وخلل كبير في العظام القطاعي نماذج الجسم الحي. ولذلك، هناك حاجة إلى طرق التثبيت موثوقة للحصول على نتائج الدراسة استنساخه وموثوق بها. البيئة الميكانيكية حول كسر الشفاء مهمة جدا لأنه يحدد الطريقة سوف تلتئم الكسور. وبالتالي، فإن اختيار جهاز تثبيت مهم جدا وينبغي اختيار بعناية اعتمادا على تصميم الدراسة، وعوامل أخرى مثل حجم الفجوة ونوع الكسر. الخواص الميكانيكية لتثبيت الجهاز علىإعادة أكثر أهمية عند دراسة التئام عظمي من عيوب العظام الكبيرة لإنشاء التثبيت التي توفر ليس فقط حجم الفجوة المستمر طوال فترة التجربة من الوزن الكامل واضعة، ولكن أيضا بيئة مثالية لالميكانيكية العظام الشفاء. يتم استخدام المثبتات الخارجية عادة في كسر العظام وخلل نماذج كبيرة الشفاء التجريبية لأن لديهم ميزة على أجهزة التثبيت الأخرى. والميزة الرئيسية لالمثبتات الخارجية هي أنها تسمح للتغيير البيئة الميكانيكية في موقع خلل في الجسم الحي دون تدخل الثانوي، وهو ما يمكن تحقيقه عن طريق تغيير أو تعديل شريط استقرار الجهاز أثناء التجربة مثل تقدم التئام العظام. علاوة على ذلك، يسمح تطبيق التحفيز الميكانيكي المحلية المحددة لتعزيز إصلاح العظام، ويوفر أيضا إمكانية لقياس صلابة من النسيج الكالس في الجسم الحي. ومع ذلك، لديها أيضا عدد قليل من أجهزة عيوبالتي تشمل: تهيج الأنسجة اللينة، والالتهابات ودبوس الكسر. للأسف، كانت هذه الغرسات غير متوفر &quot;من على الرف&quot; في وقت تطور الزرع، واضطر المحققون إلى العرف تصميم التبعي الخاصة بهم لاستخدام المقصود. ولذلك، كان العائق واحد من البحوث في هذا المجال لعدم وجود رقابة التجريبية على البيئة المحلية الميكانيكية داخل عيب قطعي كبير وكذلك خزوعات عظمية لأنه يشفي. يتم تعريف الخصائص الميكانيكية لالتبعي الخارجي من قبل، ويمكن عن طريق التضمين، وعدد كبير من المتغيرات التي تشمل: المسافة بين المسامير، قطر دبوس، دبوس المواد، وعدد من الدبابيس، التبعي طول شريط، شريط رقم التبعي، التبعي المواد شريط، شريط التبعي سمك والمسافة من سطح العظم إلى شريط التبعي (الإزاحة). من المستغرب، سوى قلة من الدراسات يمكن العثور التي حققت مساهمات الميكانيكية للمكونات الفرديةمن التبعي أو تكوينات الإطار كله المستخدمة في الدراسات القوارض 16،18،28. على سبيل المثال، أظهرت نتائج الدراسة أن واحد سيطر أحد العوامل الرئيسية المساهمة في تحديد صلابة الإجمالية للبناء التثبيت من المرونة من المسامير في ما يتعلق بهم أوفست، قطر وخصائص المواد 28. النتائج من الدراسات المذكورة أعلاه تشير بوضوح أن معرفة البيئة الميكانيكية التي يقدمها الجهاز تثبيت أمر مهم للغاية، ومع ذلك، لا يتم التحقيق في كثير من الحالات بالتفصيل. وتفيد الورقة التصميم والمواصفات وزرع في الجسم الحي من التبعي الخارجي الذي يتناول هذه المسألة. هذا التبعي يسمح أيضا لتعديل البيئة الميكانيكية كما تقدم الشفاء، وهي خاصية تمكن دراسة والميكانيكية حساسية مراحل مختلفة من عملية الشفاء في الجسم الحي. بالإضافة إلى ذلك، فضلا عن فرض ميكانيكي المحلية التي تسيطر عليها وقابلة للتكرارالبيئة القاعدة وإمكانية الحصول عليها كما يسمح للتعديل من هذه البيئة في مراحل مختلفة من التئام العظام. والتبعي قمنا بتصميم وبناء على التثبيت الخارجي، والذي يستخدم على نطاق واسع لتثبيت كسر 16-21 ونماذج عيب كبيرة في حيوانات التجارب 22-27. الفرق بين التبعي لدينا الخارجي والتصاميم الأخرى القائمة التي أعلن عنها في الأدبيات هو أن شريط استقرارها هو المضمون مع مسامير لديها قبضة ضيقة مع أسلاك كيرشنر (K-الأسلاك). هذا النوع من التصميم مسامير يتطلب أن retightened كل أسبوعين (وأحيانا حتى أسبوعية) للتأكد من أن المسافة من الإزاحة يتم الاحتفاظ كما يتم تطبيق التحميل من خلال تحمل الوزن لمنع تخفيف من شريط الاستقرار. وإذا حدث هذا التخفيف، فإنه يسمح لغير المرغوب فيها ظروف التحميل إضافية مثل الزاوي، عرضية وحركات التوائية القص حتى العظم الشفاء (على أساس التجربة الشخصية والتواصل مع researcheRS). هذا مع العلم، وقد صمم لالتبعي الخارجي على هذا النحو أنه عندما صلابة من التبعي تحتاج إلى تغيير، ويمكن تحقيق ذلك عن طريق إزالة عناصر اتصال تعلق على وحدة رئيسية حيث جعلهما دبابيس المتزايدة. تم إجراء تجربة رائدة في الجسم الحي مع التبعي خارجي جديد النموذج للتأكد من أنها تلبي جميع المطالب المقترحة قبل تصنيعه بكميات أكبر. الهدف الرئيسي لهذه الورقة هو تقديم طريقة جراحية جديدة لالتبعي الخارجي تستخدم لعيوب العظام الكبيرة وخزوعات عظمية في الفئران، مع القدرة على تغيير تصلب في الجسم الحي خلال عملية الشفاء. يتم تطبيق هذه الطريقة في تثبيت الجسم الحي على أفخاذ؛ فخذان من الفئران.

<table border="0" cellpadding="0" cellspacing="0" width="848">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:232px;">Name of Material/ Equipment</td>
			<td style="width:283px;">Company</td>
			<td style="width:117px;">Catalog Number</td>
			<td style="width:216px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RatExFix simple 100%</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.612.120</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RatExFix simple 70%</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.612.123</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RatExFix simple 40%</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.612.121</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RatExFix simple 10%</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.612.122</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:232px;">RatExFix Connection element 100%</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.612.130</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">RatExFix Connection element 70%</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.612.131</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">RatExFix Connection element 40%</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.612.132</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">RatExFix Connection element 10%</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.612.133</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">RatExFix Main body</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.611.101</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">RatExFix InterlockingScrew</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.412.110</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">RatExFix Mounting pin 0.85 mm</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.412.100</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">RatExFix Saw Guide 100% 5 mm</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.312.100</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Accu Pen 6V+</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.390.211</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">HandDrill</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.390.130</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Drill Bit 0.79 mm</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.593.203</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Gigly wire saw 0.22 mm</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.590.100</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Square box wrench 0.70 mm</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.590.112</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Square box wrench 0.50 mm</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.590.111</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Centering bit 1.00 mm</td>
			<td>RISystem AG Davos, Switzerland</td>
			<td style="width:117px;">RIS.592.205</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Scalpel Blade handle</td>
			<td style="width:283px;">Fine Science tools</td>
			<td style="width:117px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Scalpel Blade (Size 15)</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Tissue Forceps</td>
			<td style="width:283px;">Fine Science tools</td>
			<td style="width:117px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Scissors</td>
			<td style="width:283px;">Fine Science tools</td>
			<td style="width:117px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Retractor</td>
			<td style="width:283px;">Fine Science tools</td>
			<td style="width:117px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Needle Holder</td>
			<td style="width:283px;">Fine Science tools</td>
			<td style="width:117px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Henahan Elevator</td>
			<td style="width:283px;">Fine Science tools</td>
			<td style="width:117px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:232px;">S-shape curved dissecting and ligature forceps&#160;</td>
			<td style="width:283px;">Fine Science tools</td>
			<td style="width:117px;"></td>
			<td>2</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Dressing Forceps</td>
			<td style="width:283px;">Fine Science tools</td>
			<td style="width:117px;"></td>
			<td>2</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:232px;">Sterile Fenestrated drape</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td>for surgery</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sterile gauze</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td>for surgery</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">5 ml syringe&#160;</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td>&#160;for irrigation of defect</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">24-27G needle&#160;</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td>&#160;for irrigation of defect</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">1cc Insulin syringes&#160;</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td>for drug injections</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">sterile saline&#160;</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td>for bone defect irrigation</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">sterile gloves</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td>to perform surgeries</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">chlorohezadine</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td>disinfecting solution for surgical site</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Vicryl suture 4-0 with SH-1</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td>to suture muscle&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ethibond suture 3-0&#160;</td>
			<td style="width:283px;">Fisher Scientific</td>
			<td style="width:117px;"></td>
			<td>to suture skin</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Isofluorine</td>
			<td style="width:283px;">Sigma-Aldrich</td>
			<td style="width:117px;"></td>
			<td>for anesthesia</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Buprenorphine</td>
			<td style="width:283px;">Sigma-Aldrich</td>
			<td style="width:117px;"></td>
			<td>analgesia during and after the surgery</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cefazolin</td>
			<td style="width:283px;">Sigma-Aldrich</td>
			<td style="width:117px;"></td>
			<td>antibiotic during and after the surgery&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sprague-Dawley Rats or any other strain</td>
			<td>Charles River Laboratories International, Inc. (Wilmington, MA USA)&#160;</td>
			<td style="width:117px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

adjustable stiffness, external fixator for the rat femur osteotomy and segmental bone defect models

البيئة الميكانيكية حول الشفاء من كسر العظام مهمة جدا لأنه يحدد الطريقة سوف تلتئم الكسور. على مدى العقد الماضي كان هناك اهتمام سريرية كبيرة في تحسين التئام العظام عن طريق تغيير البيئة الميكانيكية من خلال تثبيت الاستقرار في جميع أنحاء الآفة. واحدة من القيد البحوث الحيوانية قبل السريرية في هذا المجال هو عدم وجود رقابة التجريبية على البيئة المحلية الميكانيكية داخل عيب قطعي كبير وكذلك خزوعات عظمية لأنها شفاء. نحن في هذه الورقة تقريرا عن تصميم واستخدام والتبعي الخارجي لدراسة شفاء قطعي عيوب العظام الكبيرة أو خزوعات عظمية. هذا الجهاز يسمح ليس فقط لصلابة المحورية التي تسيطر على آفة العظام كما أنه يشفي، لكنه تمكن أيضا تغيير صلابة أثناء عملية الشفاء في الجسم الحي. وقد أظهرت التجارب التي أجريت أن التبعي كانت قادرة على الحفاظ على 5 ملم الفجوة عيب الفخذ في الفئران في الجسم الحي خلال القفص بلا قيودالنشاط لمدة 8 أسابيع على الأقل. وبالمثل، لاحظنا أي تشويه أو التهابات، بما في ذلك التهابات دبوس خلال فترة الشفاء بأكملها. هذه النتائج تثبت أن لدينا التبعي الخارجي وضعت حديثا كان قادرا على تحقيق الاستقرار استنساخه وموحدة، وتغيير البيئة الميكانيكية في الجسم الحي الفئران عيوب العظام الكبيرة ومختلف خزوعات عظمية الحجم. هذا يؤكد أن جهاز التثبيت الخارجي هو مناسب تماما لتحقيقات البحوث قبل السريرية باستخدام نموذج الفئران في مجال تجديد وإصلاح العظام.

مواصفات التصميم استقرار عظمة الفخذ الفئران مع نظام التثبيت الخارجي يمكن إنشاء خزوعات عظمية 0،5-5 ملم. النظام التبعي الخارجي هو التبعي الخارجي مقفل مصنوعة من البولي كيتون الأثير (نظرة خاطفة - [الجسم الرئيسي]) وسبائك التيتانيوم والألو...

Watch this Scientific Journal Video about Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models at JoVE.com

Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models

One constraint of preclinical research in the field of bone repair is the lack of experimental control over the local mechanical environment within a healing bone lesion. We report the design and use of an external fixator for bone repair with the ability to change fixator stiffness in vivo.

تصلب قابل للتعديل، التبعي الخارجي للفأر عظم الفخذ العظم والقطاعي العظام عيب نماذج

The mechanical environment around the healing of broken bone is very important as it determines the way the fracture will heal. Over the past decade there ...

adjustable-stiffness-external-fixator-for-rat-femur-osteotomy

Research

JoVE Journal

Medicine

22.4K Views.  Queensland University of Technology. One constraint of preclinical research in the field of bone repair is the lack of experimental control over the local mechanical environment within a healing bone lesion. We report the design and use of an external fixator for bone repair with the ability to change fixator stiffness in vivo.

Video: Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models

Models of Bone Metastasis

Bone metastases are a common occurrence in several malignancies, including breast, prostate, and lung. Once established in bone, tumors are responsible for significant morbidity and mortality1. Thus, there is a significant need to understand the molecular mechanisms controlling the establishment, growth and activity of tumors in bone. Several in vivo models have been established to study these events and each has specific benefits and limitations. The most commonly used model utilizes intracardiac inoculation of tumor cells directly into the arterial blood supply of athymic (nude) BalbC mice. This procedure can be applied to many different tumor types (including PC-3 prostate cancer, lung carcinoma, and mouse mammary fat pad tumors); however, in this manuscript we will focus on the breast cancer model, MDA-MB-231. In this model we utilize a highly bone-selective clone, originally derived in Dr. Mundy's group in San Antonio2, that has since been transfected for GFP expression and re-cloned by our group3. This clone is a bone metastatic variant with a high rate of osteotropism and very little metastasis to lung, liver, or adrenal glands. While intracardiac injections are most commonly used for studies of bone metastasis2, in certain instances intratibial4 or mammary fat pad injections are more appropriate. Intracardiac injections are typically performed when using human tumor cells with the goal of monitoring later stages of metastasis, specifically the ability of cancer cells to arrest in bone, survive, proliferate, and establish tumors that develop into cancer-induced bone disease. Intratibial injections are performed if focusing on the relationship of cancer cells and bone after a tumor has metastasized to bone, which correlates roughly to established metastatic bone disease. Neither of these models recapitulates early steps in the metastatic process prior to embolism and entry of tumor cells into the circulation. If monitoring primary tumor growth or metastasis from the primary site to bone, then mammary fat pad inoculations are usually preferred; however, very few tumor cell lines will consistently metastasize to bone from the primary site, with 4T1 bone-preferential clones, a mouse mammary carcinoma, being the exception 5,6.
This manuscript details inoculation procedures and highlights key steps in post inoculation analyses. Specifically, it includes cell culture, tumor cell inoculation procedures for intracardiac and intratibial inoculations, as well as brief information regarding weekly monitoring by x-ray, fluorescence and histomorphometric analyses.

Animal models are frequently utilized to study cancer metastasis to bone. In this protocol we will describe two common methods of tumor inoculation for bone metastasis studies and briefly describe some of the analyses utilized to monitor and quantify these models.

نماذج من الانبثاث العظام

Bone metastases are a common occurrence in several malignancies, including breast, prostate, and lung. Once established in bone, tumors are responsible ...

Procedure for Human Saphenous Veins Ex Vivo Perfusion and External Reinforcement

The mainstay of contemporary therapies for extensive occlusive arterial disease is venous bypass graft. However, its durability is threatened by intimal hyperplasia (IH) that eventually leads to vessel occlusion and graft failure. Mechanical forces, particularly low shear stress and high wall tension, are thought to initiate and to sustain these cellular and molecular changes, but their exact contribution remains to be unraveled. To selectively evaluate the role of pressure and shear stress on the biology of IH, an ex&#160;vivo perfusion system (EVPS) was created to perfuse segments of human saphenous veins under arterial regimen (high shear stress and high pressure). Further technical innovations allowed the simultaneous perfusion of two segments from the same vein, one reinforced with an external mesh. Veins were harvested using a no-touch technique and immediately transferred to the laboratory for assembly in the EVPS. One segment of the freshly isolated vein was not perfused (control, day 0). The two others segments were perfused for up to 7 days, one being completely sheltered with a 4 mm (diameter) external mesh. The pressure, flow velocity, and pulse rate were continuously monitored and adjusted to mimic the hemodynamic conditions prevailing in the femoral artery. Upon completion of the perfusion, veins were dismounted and used for histological and molecular analysis. Under ex&#160;vivo conditions, high pressure perfusion (arterial, mean = 100 mm Hg) is sufficient to generate IH and remodeling of human veins. These alterations are reduced in the presence of an external polyester mesh.

Procedure for Human Saphenous Veins Ex Vivo Perfusion and External Reinforcement

The mechanisms leading to the development of intimal hyperplasia (IH) and vein graft failure are still poorly understood. This study describes an ex&#160;vivo system to perfuse human veins under controlled flow and pressure. Furthermore the efficiency of external mesh reinforcement to limit the development of IH was evaluated.

إجراءات الصافن عروق الإنسان<em&gt; فيفو السابقين</em&gt; الإرواء والتعزيز الخارجي

The mainstay of contemporary therapies for extensive occlusive arterial disease is venous bypass graft. However, its durability is threatened by intimal ...

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.

بسيطة الحرجة الحجم فخذي عيب النموذجي في الفئران

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 ...

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.

إنشاء القطاعي فخذي الحرجة حجم عيب النموذجي في الفئران استقرت بواسطة لوحة تثبيت طرفي العظم

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 ...

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.

ومسمار داخل النقي قفل لالموحدة التثبيت من عظم الفخذ خزوعات عظمية لتحليل عادي وعيب العظام شفاء في الفئران

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

Method of Direct Segmental Intra-hepatic Delivery Using a Rat Liver Hilar Clamp Model

Major hepatic surgery with inflow occlusion, and liver transplantation, necessitate a period of warm ischemia, and a period of reperfusion leading to ischemia/reperfusion (I/R) injury with myriad negative consequences. Potential I/R injury in marginal organs destined for liver transplantation contributes to the current donor shortage secondary to a decreased organ utilization rate. A significant need exists to explore hepatic I/R injury in order to mediate its impact on graft function in transplantation. Rat liver hilar clamp models are used to investigate the impact of different molecules on hepatic I/R injury. Depending on the model, these molecules have been delivered using inhalation, epidural infusion, intraperitoneal injection, intravenous administration or injection into the peripheral superior mesenteric vein. A rat liver hilar clamp model has been developed for use in studying the impact of pharmacologic molecules in ameliorating I/R injury. The described model for rat liver hilar clamp includes direct cannulation of the portal supply to the ischemic hepatic segment via a side branch of the portal vein, allowing for direct segmental hepatic delivery. Our approach is to induce ischemia in the left lateral and median lobes for 60 min, during which time the substance under study is infused. In this case, pegylated-superoxide dismutase (PEG-SOD), a free radical scavenger, is infused directly into the ischemic segment. This series of experiments demonstrates that infusion of PEG-SOD is protective against hepatic I/R injury. Advantages of this approach include direct injection of the molecule into the ischemic segment with consequent decrease in volume of distribution and reduction in systemic side effects.

A unique rat liver hilar clamp model was developed for studying the impact of pharmacologic molecules in ameliorating ischemia-reperfusion injury. This model includes direct cannulation of the portal supply to the ischemic liver segment via a branch of the portal vein, allowing for direct hepatic delivery.

طريقة التسليم المباشر القطاعي البينية الكبد باستخدام نموذج الفأر الكبد نقيري المشبك

Major hepatic surgery with inflow occlusion, and liver transplantation, necessitate a period of warm ischemia, and a period of reperfusion leading to ...

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.

في فيفو تقييم التنمية دشبذ الكسر أثناء التئام العظام في الفئران باستخدام جهاز الصدمة المتوافقة مع التصوير بالرنين المغناطيسي لعظم الفخذ الماوس

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

Using a Knee Arthrometer to Evaluate Tissue-specific Contributions to Knee Flexion Contracture in the Rat

Normal knee range of motion (ROM) is critical to well-being and allows one to perform basic activities such as walking, climbing stairs and sitting. Lost ROM is called a joint contracture and results in increased morbidity. Due to the difficulty of reversing established knee contractures, early detection is important, and hence, knowing risk factors for their development is essential. The rat represents a good model with which the effect of an intervention can be studied due to the similarity of rat knee anatomy to that of humans, the rat's ability to tolerate long durations of knee immobilization in flexion, and because mechanical data can be correlated with histologic and biochemical analysis of knee tissue.
Using an automated arthrometer, we demonstrate a validated, precise, reproducible, user-independent method of measuring the extension ROM of the rat knee joint at specific torques. This arthrometer can be used to determine the effects of interventions on knee joint ROM in the rat.

The goal of the protocol is to measure the extension range of motion of the rat knee. The effects of various diseases that increase the stiffness of the knee joint and the effectiveness of treatments can be quantified.

استخدام أرثروميتير ركبة تقييم المساهمات الخاصة بالانسجة إلى انكماش انثناء الركبة في الفئران

Normal knee range of motion (ROM) is critical to well-being and allows one to perform basic activities such as walking, climbing stairs and sitting. Lost ...

A Rat Carotid Artery Pressure-Controlled Segmental Balloon Injury with Periadventitial Therapeutic Application

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the luminal surface area in arteries thereby reducing adequate blood flow to organs and distal tissues. Clinically, revascularization procedures such as balloon angioplasty with or without stent placement aim to restore blood flow. Although these procedures reestablish blood flow by reducing plaque burden, they damage the vessel wall, which initiates the arterial healing response. The prolonged healing response causes arterial restenosis, or re-narrowing, ultimately limiting the long-term success of these revascularization procedures. Therefore, preclinical animal models are integral for analyzing the pathophysiological mechanisms driving restenosis, and provide the opportunity to test novel therapeutic strategies. Murine models are cheaper and easier to operate on than large animal models. Balloon or wire injury are the two commonly accepted injury modalities used in murine models. Balloon injury models in particular mimic the clinical angioplasty procedure and cause adequate damage to the artery for the development of restenosis. Herein we describe the surgical details for performing and histologically analyzing the modified, pressure-controlled rat carotid artery balloon injury model. Additionally, this protocol highlights how local periadventitial application of therapeutics can be used to inhibit neointimal hyperplasia. Lastly, we present light sheet fluorescence microscopy as a novel approach for imaging and visualizing the arterial injury in three-dimensions.

The rat carotid artery balloon injury mimics the clinical angioplasty procedure performed to restore blood flow in atherosclerotic vessels. This model induces the arterial injury response by distending the arterial wall, and denuding the intimal layer of endothelial cells, ultimately causing remodeling and an intimal hyperplastic response.

إصابة بالون فئلي من ضغط الشريان السباتي الجرذ مع تطبيق علاجي شامل

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the ...

Protocol for Developing a Femur Osteotomy Model in Wistar Albino Rats

Fracture healing is a physiological process resulting in the regeneration of bone defects by the coordinated action of osteoblasts and osteoclasts. Osteoanabolic drugs have the potential to augment the repair of fractures but have constraints like high costs or undesirable side effects. The bone healing potential of a drug can initially be determined by in vitro studies, but in vivo studies are needed for the final proof of concept. Our objective was to develop a femur osteotomy rodent model that could help researchers understand the development of callus formation following fracture of the shaft of the femur and that could help establish whether a potential drug has bone healing properties. Adult male Wistar albino rats were used after Institutional Animal Ethics Committee clearance. The rodents were anesthetized, and under aseptic conditions, complete transverse fractures at the middle one-third of the shafts of the femurs were created using open osteotomy. The fractures were reduced and internally fixed using intramedullary K-wires, and secondary fracture healing was allowed to take place. After surgery, intraperitoneal analgesics and antibiotics were given for 5 days. Sequential weekly x-rays assessed callus formation. The rats were sacrificed based on radiologically pre-determined time points, and the development of the fracture callus was analyzed radiologically and using immunohistochemistry.

Here, we present a protocol to iatrogenically fracture the shaft of the femur of Wistar albino rats and follow up on the development of the callus. This femur osteotomy model can help researchers evaluate the process of fracture healing and to study how a drug could influence fracture healing.

بروتوكول لتطوير نموذج قطع عظم الفخذ في فئران ويستار ألبينو

Fracture healing is a physiological process resulting in the regeneration of bone defects by the coordinated action of osteoblasts and osteoclasts. ...