膝关节翻修胫骨侧骨缺损打压植骨术后初始稳定性的研究

Mechanical Test of Impaction Bone Grafting in Revision of Tibia (Initial Stability of Short and Long Stem)

目的研究膝关节翻修胫骨侧骨缺损采用两种假体打压植骨术后的初始稳定性。方法取5具尸体的胫骨10根,制造T3型(AORI分型)的包容性骨缺损,随机选择同一尸体的左右侧胫骨进行长短柄两种假体的打压植骨翻修,观察松质骨骨密度的变化,进行生物力学测试。结果长短柄假体在1000N循环载荷下的微动没有统计学差别,假体的微动与假体下方移植骨密度呈负线性相关。结论打压植骨技术可以用于胫骨侧严重骨缺损的治疗,在完整皮质骨支撑、骨水泥固定的前提下,长短柄两种假体都能够达到足够的初始稳定。

Objective To investigate the effect of the type of stem and the graft impaction on the initial stability of the tray in revision total knee arthroplasty through impaetion bone grafting. Methods Ten tibia from 5 cadavers were randomizedly divided into two groups. The T3 type （AORI classification） contained bone defect was made. The trays with short （35 mm） or long （75 mm） stems were randomizedly implanted in the tibia on both sides from the same cadaver using morsellised impaetion bone grafting. Bone mineral density around the implant and X- ray image were observed. The biomeehanieal tests were performed under circular load （1 000 N）. Results There was no statistically significant difference in the mlcromotion between the two types of stems. The migration of stem was correlated inversely with the density of the impacted graft. Conclusion The impaetion bone grafting can be employed in the severe bone defect in tibia. If support of the intact cortex and the bone cement is sufficient, both short and long stems can achieve adequate initial stability.