Related Experiment Video
Updated: May 22, 2026
Anterior Cruciate Ligament Transection and Synovial Fluid Lavage in a Rodent Model to Study Joint Inflammation and Posttraumatic Osteoarthritis
Published on: September 2, 2025
Inhibitory effect of synovial fluid on tendon-to-bone healing: an experimental study in rabbits
1Orthopaedic Center of PLA, The 88th Hospital of PLA, Tai'an, China. sl88h@163.com
Purpose:
The purpose of this study was to explore the effects of joint synovial fluid on tendon-to-bone healing in intra-articular ligament reconstruction of the knee.
Methods:
We divided 40 female New Zealand white rabbits into 4 groups randomly, with 10 animals in each group. Transfer of the semitendinosus tendon to the tibial bone tunnel was performed to create tendon-to-bone healing models. An intra-articular bone tunnel (IBT) was used on the left side and an extra-articular bone tunnel (EBT) on the right. Histologic evaluation was performed at 2, 4, and 8 weeks after the operation and biomechanical testing at 8 weeks.
Results:
On the basis of fibroblast proliferation, collagen fiber density, collagen fiber orientation, and tendon-to-bone connection, histologic scores were significantly lower in the IBT group than in the EBT group at 2, 4, and 8 weeks. Cell counts per high-power field at the tendon-bone interface were significantly lower in the IBT group than in the EBT group at 2 and 4 weeks. In addition, biomechanical testing showed that the IBT group was significantly inferior to the EBT group in terms of ultimate failure load, yield load, and stiffness. There was also a significant difference between the 2 groups in failure mode.
Conclusions:
Joint synovial fluid appeared to have an inhibitory effect on tendon-to-bone healing in rabbits at an early stage.
Clinical Relevance:
Our findings imply that prevention of infiltration of joint synovial fluid into the bone tunnel might be beneficial in improving the clinical outcome of cruciate ligament reconstruction of the knee.
