锁定加压钢板置入内固定治疗胫骨骨折的力学分析

Mechanical analysis of locking compression plate fixation for the treatment of tibial fracture

背景:锁定加压钢板结合了传统钢板和支架原理,即头部有锁定螺纹的螺钉和钢板锁钉孔构成的内固定支架锁定单元,又有传统螺钉和动力加压孔构成的内固定支架加压单元,在骨折的内固定治疗方面具有很多优势。目的:分析锁定加压钢板置入内固定治疗胫骨骨折的生物力学特点,以及在胫骨骨折治疗中的疗效。方法:锁定加压钢板是依靠钢板与螺钉的成角稳定性和螺钉与骨之间的把持力来实现骨折内固定的。骨髓腔细小时应避免螺钉尖端损伤近端皮质的骨螺纹,应更换为双皮质自攻螺钉至少在对侧骨皮质获得把持力。骨质疏松植入螺钉,由于单皮质骨螺钉产生的工作长度减少,在所有骨折块均使用双皮质自攻螺钉,以提高螺钉工作长度。当长骨轴线与钢板对线不良时,要么打入长自攻螺钉,要么改变角度打入标准螺钉。锁定加压钢板应选择适宜的长度,钢板的长度取决钢板跨越比和钢板螺钉密度,钢板与螺钉间的应力还受螺钉数量和位置的影响。结果与结论:锁定加压钢板置入内固定可应用于骨干或干骺端的简单骨折、粉碎性骨折、关节内及关节周围骨折、骨折延迟愈合、闭合或开放截骨术和不适合髓内钉固定的骨干骨折,对于骨质疏松骨折和假体周围骨折的内固定有很好的成角稳定性和把持力。锁定加压钢板置入内固定治疗胫骨骨干骨折均取得满意的疗效,符合生物力学固定原理。需要术者熟练掌握锁定加压钢板的内固定技术,避免由于失误导致内固定的失败。

BACKGROUND： Locking compression plate combines with traditional steel plate and bracket principle, which has locking threaded screws on head and mounting bracket lock unit composed with steel locking nail holes, as well as the intemal fixation bracket pressurized unit composed with traditional screws and dynamic compression holes So the locking compression plate has many advantages in the treatment of fracture fixation. OBJECTIVE： To analyze the biomechanical characteristics and effect of locking compression plate in the treatment of tibial fracture.METHODS： Locking compression plate could achieve the fracture fixation depended on the angular stability of steel plate and screws and the pullout strength between crews and bone. When the marrow cavitsy was small, the top of the screw should be avoided to damage the proximal cortical bone threaded, and then the screws should be changed into the bicortical self-tapping screws at least in order to obtain the pullout strength from the contralateral cortical bone. Screw implantation for the treatment of osteoporosis, due to the reduced working length of unicortical screw fixation, the bicortical self-tapping screws were used in all the fracture fragments to improve the working length of the screws. When the alignment between the long bone axis and steel plate was not in order,implanting the long self-tapping screws or changing the angle to implant the standard screws were preferred. The locking compression plate should select a appropriate length. The length of the locking compression plate depended on the length and the density of the plate and screw. The stress between plate and screw was also affected by the number and the position of the screw.RESULTS AND CONCLUSION： Locking compression plate fixation can be used for the treatment of backbone or metaphyseal simple fracture, comminuted fracture, intra-articular and periarticular fractures, delayed fracture healing, closed or open osteotomy and the shaft fracture which is not suitable for intramedullary nailing. And for the fixation of osteoPorotic fractures and periprosthetic fractures, the locking compression plate has good angular stability and pullout strength. Locking compression plate fixation for the treatment of tibial shaft fractures has achieved satisfactory results, which in line with the biomechanics fixed principles. Surgeons need to be familiar with the fixation techniques of locking compression plate, in order to avoid mistakes-caused failure fixation.