前后交叉韧带同时重建固定角度实验研究

EXPERIMENTAL STUDY ON FIXED ANGLE ADJUSTMENT IN SIMULTANEOUS RECONSTRUCTION OF ANTEPIOR AND POSTERIOR CRUCIATE LIGAMENTS

目的探讨采用自体半腱肌肌腱同时重建前交叉韧带(anterior cruciate ligament,ACL)和后交叉韧带(posterior cruciate ligament,PCL)移植肌腱固定时膝关节屈曲最佳角度。方法清洁级6～8月龄新西兰大白兔24只,雌雄不限,体重(2.5±0.2)kg,根据重建韧带固定时膝关节屈曲角度不同,随机分为3组(n=8)。取双侧后肢半腱肌肌腱,同时重建右后肢PCL及ACL,并分别于膝关节屈曲90°(A组)、60°(B组)、30°(C组)位固定。术后观察实验动物一般情况;术后3个月时,采用空气栓塞法处死实验动物,取膝关节远、近端各10 cm长肢体,行伸屈等长实验、前后位移实验、膝关节内外旋转实验。结果实验动物均存活至实验完成。3组间ACL及PCL最大位移比较,差异均无统计学意义(P>0.05)。各组前、后方位移均<1 mm,提示前、后稳定性均良好;A组屈曲30°时前方位移及屈曲90°时后方位移均较C组大,差异均有统计学意义(P<0.05)。A组内、外旋转角度与C组比较,差异均有统计学意义(P<0.05);其余各组间比较,差异均无统计学意义(P>0.05)。结论同时重建兔ACL及PCL,以屈曲60°行韧带固定效果最佳。

Objective To explore the best flexion angle of the transplantation tendon tor fixing joint m simultaneously reconstructing of the anterior cruciate ligament （ACL） and posterior cruciate ligament （PCL） using semitendinosus tendon as autologous graft. Methods Twenty-four clean level New Zealand White rabbits [（aged 6-8 months, male or female, and weighing （2.5±0.2） kg] were selected and divided randomly into 3 groups （n=8） according to fixation angle of the reconstructed ligaments. The bilateral semitendinosus tendons of hind legs were used to reconstruct the PCL and ACL of right hind leg, and the reconstructed ligaments were fixed at knee flexion angles of 90° （group A）, 60° （group B）, and 30° （group A）. The rabbit general situation was observed after operation, and the specimens of the knee joints （including 10 cm distal end and 10 cm proximal end） were harvested for testing extension and flexion, displacement, and internal and external rotation at 3 months after operation. Results All the rabbits survived to the end of experiment. There was no significant difference in maximal displacements of ACL and PCL among 3 groups （P 〉 0.05）. The anterior and posterior displacements of shift in 3 groups were less than 1 mm, suggesting good stability. The anterior displacement and the posterior displacement at 30° flexion and 90° flexion in group A were significantly larger than those in group C （P 〈 0.05）. There were significant differences in internal rotation angle and external rotation angle between group A and group C （P 〈 0.05）, and there was no significant difference among other groups （P 〉 0.05）. Conclusion When simultaneously reconstructing ACL and PCL, the knee flexion angle of 60° for fixing the reconstructed ligaments can achieve the best effect.