Our study is the first to use genipin, a naturally occurring collagen cross-linking agent, as a therapeutic agent to treat superficial digital flexor tendon (SDFT) injuries in horses. The promising approach of intratendinous genipin injection and tendon mechanical enhancement could be a viable alternative to current therapies for SDFT injuries.

Tendon injuries are a career limiting or ending condition in horses. Genipin (GP), an exogenous collagen crosslinker, provides ex-vivo tendon mechanical augmentation and excellent biosafety. The main objective of this study is to investigate treatment success of GP-induced collagen crosslinking in a clinical application in horses with superficial digital flexor tendon (SDFT) injuries. Horses with an AAEP (American Association of American Practitioners) lameness score > 0 and sonographically confirmed tendinopathy are treated with intratendinous GP injection (IGI) and controlled exercise. Minimal follow-up was set at 12 months. Outcome factors are lameness (AAEP lameness score), soundness, assessment of return to previous use, and re-injury. Additionally, adverse effects are recorded.

Inclusion Criteria:

• clinical and sonographic evidence of a tendon injury

Exclusion Criteria:

• in the final analysis, only superficial digital flexor tendon injuries were included
• if follow-up was less than 12 m due to euthanasia, death or other reasons, horses were excluded from the study