Tenosynovitis associated with longitudinal tears of the digital flexor tendons in horses: a report of 20 cases.

This article reports on a previously unidentified condition in horses involving longitudinal tears in the superficial or deep digital flexor tendons within the digital flexor tendon sheath, often coupled with chronic tenosynovitis. Out of the twenty studied cases, surgical investigation proved instrumental in diagnosing and treating the condition, with satisfactory results achieved in a majority of the horses.

Detailed Overview of the Research

• The researchers examined a series of twenty cases where horses experienced previously unidentified longitudinal tears in either their superficial or deep digital flexor tendons. In all incidents, the digital flexor tendon sheaths were markedly distended and the horses were all noticeably lame.
• Ultrasonography procedures were conducted but were unable to definitively identify the cause, revealing only nonspecific signs of chronic tenosynovitis. Definitive diagnosis was only established through either tenoscopy or open surgical exploration.

Detailed Procedures and Treatment

• Out of the twenty total studied cases, one horse was affected bilaterally, nineteen were defects involving the deep digital flexor tendon, and two included torn manica flexoria of the superficial digital flexor tendon.
• In seven of these cases, surgeons treated the lesions on the deep digital flexor tendon by removing the torn fibrils under tenoscopic control. The remaining cases required more invasive procedures, involving the removal of the torn elements and repairing the defects with absorbable suture material.
• Regardless of the exact procedure, all wounded areas were closed up, with all open procedures specifically involving the repair of the palmar/plantar annular ligament.

Results and Conclusions

• Following treatment, eleven horses became sound and returned to their regular work routines, while three horses showed improvement but remained lame when undertaking work. Two horses showed no signs of improvement post-treatment.
• At the time of this study’s publication, four horses were both sound and undergoing controlled ascending exercise regimes.
• Capping off the study, researchers concluded that these types of longitudinal tears should henceforth be recognized as important considerations in the differential diagnosis of tenosynovitis of the digital flexor tendon sheath.
• In terms of practical application, the results suggest that accurate diagnosis and specific treatment both justify surgical investigation for such cases — coming out as a productive means in the majority of cases studied.