Manassero Mathieu, Decambron Adeline, Huu Thong Bui Truong, Viateau Véronique, Bensidhoum Morad, Petite Hervé
Laboratoire de Bioingénierie et Biomécanique Ostéo-Articulaires (B2OA - UMR CNRS 7052), Université Paris Diderot; Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est.
Laboratoire de Bioingénierie et Biomécanique Ostéo-Articulaires (B2OA - UMR CNRS 7052), Université Paris Diderot.
J Vis Exp. 2016 Oct 12(116):52940. doi: 10.3791/52940.
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.
使用组织工程骨构建体是一种有吸引力的策略，可克服自体骨移植治疗大面积骨缺损的缺点。作为一种模式生物，小鼠已广泛应用于骨相关研究。然而，小鼠大段骨干骨缺损模型较少，且常采用填充骨髓腔的骨固定方法，无法提供最佳的机械稳定性。本研究的目的是在裸鼠中建立一个临界尺寸的节段性股骨缺损模型。使用专用夹具在股骨中干进行3.5毫米的截骨术（约占股骨长度的25%），并用位于前方的锁定钢板和4枚锁定螺钉进行固定。随后，骨缺损处要么保持空的，要么填充骨替代物（同基因骨移植或珊瑚支架）。术后10周动物处死后，通过X线摄影和体内微型计算机断层扫描对骨愈合进行无创监测，随后通过体外微型计算机断层扫描和不脱钙组织学进行评估。所有小鼠恢复良好，术后一天内即可完全负重。此外，在整个研究中测试的所有动物中均实现了稳定的骨固定和植入材料的一致固定。当骨缺损保持空的时，始终会出现骨不连。相比之下，当骨缺损填充同基因骨移植时，总能观察到骨愈合。当骨缺损填充珊瑚支架时，在骨切除边缘与支架的界面以及支架内短距离内观察到新形成的骨。本模型描述了一种通过钢板接骨术稳定的可重复的临界尺寸股骨缺损，小鼠发病率低。新的负重节段性骨缺损模型可能有助于研究与骨科应用相关的骨再生潜在机制。
