Reconstruction of ACL with free autogenous B-PT-B grafts
- VernacularTitle:骨-髌腱-骨自体移植重建前十字韧带的研究
- Author:
Xing TENG
;
Manyi WANG
;
Xiaoyuan HUANG
- Publication Type:Journal Article
- Keywords:
Anterior cruciate ligament;
Animal experimentation;
Biomechanics;
Histology
- From:
Chinese Journal of Orthopaedics
2001;0(08):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the characteristics of grafts after reconstruction of ACL with autogenous bone-patellar tendon-bone(B-PT-B)grafts. Methods Reconstruction of anterior cruciate ligament with free B-PT-B autograft fixed with interference screw was performed on 39 adult dogs. Mechanical testing was conducted on the grafts by translating the tibia anteriorly with the knee in 90 degrees of flexion, until complete failure. Failure site, cross sectional area, strength, stiffness and stress were documented. After decalcification and HE staining, the transformation of the intra-tunnel and intra-articular ligaments was evaluated, and the histological observation was conducted for the healing in the bone-tunnel, patellar tendon-tunnel and bone-patellar tendon interface. Results Union occurred in the bone-tunnel interface at 4th week. The patellar tendon-tunnel interface was linked by Sharpey's like fibers at 52nd week, the cement line and the tendency of chondrocyte lining were found. Mechanical testing of graft revealed that the rupture always occurred at mid-portion of ligaments instead of pulling-out from the tunnel under tension stress. Compared with the control group, the strength, stiffness and stress of the graft were 38%, 58% and 50% of normal anterior cruciate ligament at 52nd week respectively. Conclusion The union in the bone-tunnel interface occurs at 4th week, much earlier than the healing of the patellar tendon-tunnel interface. The healing of the tendon to tunnel presents to be indirect insertion at 52nd week with alignment of chondrocytes, which signifies the still ongoing of healing process at the interface. After fixation with interference screw for 4 weeks, the tendon proved to be the weakest part in bone-tendon-bone complex. No need to worry about the biomechanical character of the new insertion site during rehabilitation activities. The attachment fixed by interference screw is stable not only immediately after surgery but also during the healing of the insertion and the transformation of ligament. One year after reconstruction, the mechanical quality of the grafted tendon still remains inferior to that of normal anterior cruciate ligament in spite of similar histological structure. Protective device should be recommended during active activity.
