血管袢骨膜内腓骨组合移植修复长段粗骨缺损的实验研究

A biomechanic research on repairing long and thick bone defects by double fibular transplanation under periosteum with vascular loop

目的研究评价带血运单腓骨移植、骨膜外腓骨组合移植及骨膜内腓骨组合移植修复长段粗骨缺损的能力差异,为临床长段粗骨缺损的修复提供新的有效术式及理论依据。方法72只新西兰大白兔,制成胫骨中上段10mm骨缺损模型,用1.2mm双克氏针内固定。实验组:截取腓骨24mm,保护附着的肌肉和腓血管制成带血管蒂的腓骨瓣,在腓骨前内侧纵行切开骨膜并剥离至周径的1/3,截断形成两段各为12mm的腓骨,将腓骨折叠,缝合骨膜两游离缘形成一完整骨膜包裹的双腓骨,两腓骨相对面无骨膜,骨皮质直接对合,两骨端用5-0丝线捆扎,向内侧移位至胫骨缺损处,腓骨远近端插入胫骨髓腔内。对照Ⅰ组:将截取带骨膜的腓骨12mm向近端游离,向内侧移位至胫骨缺损处,腓骨远近端插入胫骨髓腔内。对照Ⅱ组:截取腓骨24mm,截断形成两段各为12mm的腓骨,将带骨膜的双段腓骨折叠,腓骨折叠后相邻面腓骨骨膜保持完整,两骨端用5-0丝线捆扎,对照组内固定同实验组。术后石膏外固定于屈膝屈踝90°位。于术后2、4、8、12、16周每组取4只,分别摄X线片;测定骨密度,进行生物力学测试。通过观测指标对比三种术式修复骨缺损的差异。结果本试验中对照Ⅰ组4只出现骨折,对照Ⅱ组2只出现骨折,实验组未发生骨折。X线片示实验组骨小梁排列整齐,腓骨明显增粗,骨髓腔再通。骨密?

Objective To compare biomechanically the different effects of mono fibular transplantation, extraperiosteal double fibular transplantation and subperiosteal double fibular transplanation in repairing long and thick bone defects, so as to provide evidence for a new effective method of repairing bone defects. Methods 72 healthy rabbits were divided randomly into 3 groups and made into animal models of 10 mm tibial defect. They were fixed with two 1.2 mm Kirschner wires. In the experimental group, a 24 mm vascularized fibula was harvested and divided into 2 segments evenly. The anterior lateral fibular periosteum was incised vertically and 1/3 of the circumference was stripped. The 2 segments of vascularized fibula with periosteum were folded, and the stripped periosteum was then sutured to wrap the double fibulae that contacted directly without periosteum. Both ends of the fibular periosteum were tied up with 5/0 suture. The fibulae were implanted to connect the tibial defects with both ends fixed in the medullary cavity of the tibia. In control group Ⅰ, a 12 mm fibula vascularized was harvested to fill the tibial defects. In control group Ⅱ, a 24 mm fibula vascularized was harvested and divided into 2 segments evenly. The 2 parts of the fibula with periosteum were folded with the neighboring sides of periosteum remaining intact. Both ends of the fibular periosteum were tied up with 5/0 suture. The operated limbs were immobilized with plaster. 4 rabbits in each group were examed by X ray to determine their bone mineral density and biomechanic index at 2, 4, 8, 12, 16 weeks rescpectively. The different effects of the procedures were compared on the basis of such observations. Results 4 fractures occurred in control group Ⅰ, 2 in control group Ⅱand zero in the experimental group. The X ray results showed that in the experimental group the bone trabecula lined up in order, and the fibula became thick significantly with the medullary cavity recanalized. The bone mineral density in the experimental group was significantly higher than that in both control groups (P< 0.01). The biomechanical indexes in the experimental group, such as average maximal load, torque, and shearing stress of the transplanted bone, were all significantly better than those in the control groups (P< 0.01). Conclusions The subperiosteal double fibular transplanation is the most ideal biomechnically and thus recommendable in clinics. With the periosteum sutured, the subperiosteal osteogenesis and the mechanical stress can stimulate the transplanted fibula to grow thicker. When the 2 segments of transplanted fibulae heal, their anti stress ability will be strong enough to prevent the refracture of the transplanted bones.