Comparison of healing in forelimb and hindlimb surgically induced core lesions of the equine superficial digital flexor tendon.

This research investigates whether the healing process of surgically-induced superficial digital flexor tendon (SDFT) core lesions in horses’ front and hind legs are similar or not. The findings demonstrate significant differences in a few parameters of tendon healing, leading to challenges in using all four legs in tendon injury studies.

Research Methodology

• The study focused on surgically induced tendon core lesions in the superficial digital flexor tendons of both the front and back legs of eight horses. One forelimb and one hindlimb were randomly chosen for each horse for the injection of saline one and two weeks after surgery.
• The healing process was monitored carefully through clinical evaluations and ultrasound examinations.
• After a period of 24 weeks, the tendons were collected, and the different parameters, such as biochemical, biomechanical, and histological properties, were analyzed.

Research Findings

• After 24 weeks from surgery, it was found that the front leg SDFT lesions possessed a higher color Doppler ultrasound vascularization score and glycosaminoglycan concentration, whereas their hydroxylysylpyridinoline content was significantly lower when compared to the hindlimbs.
• The data show that there are significant differences in several critical parameters of tendon healing between front and back leg SDFT surgical lesions after 24 weeks from surgery.

Conclusions and Implications

• The findings challenge the method of using all four legs in the study of tendon injury. Because of the few important differences seen in the healing process between front and back leg tendons, interpreting the results gathered might involve a significant degree of complexity.
• The conclusion made by the research is that further studies using four-limb models for tendon injury studies should not be undertaken until there is a deeper understanding of the reasons for these differences.