Penetrating injuries near the fetlock can be very serious because of their proximity to the deep digital flexor tendon (DDFT), which flexes the lower limb joints, and its sheath. While a horse might have only a small cut or puncture wound, the internal injury can create severe or even non-weight-bearing lameness. If left untreated or undertreated (with only administration of antibiotics, phenylbutazone, etc.), chronic infection can result, leaving the horse permanently lame.

Tenoscopy is a technique similar to arthroscopy, in which tiny incisions in the skin allow for careful visualization and cleaning of tendon injuries. Recently, researchers from Kansas State University published a study that examined the effectiveness of tenoscopy in managing open DDFT sheath injuries.

Twenty horses were treated using tenoscopy to break down and flush out foreign material, fibrin, and other debris. Seventeen were available for long-term followup. Of these, 10 returned to full work, four to reduced work, and three were chronically lame. Interestingly, the average time that elapsed after injury and prior to tenoscopy was two weeks, yet the technique was still quite successful, with 14 of 17 horses (84%) returning to work. In comparison, only 56% of horses treated conservatively have enjoyed such success. The exact anatomical location of the injury had no bearing on prognosis in this study, but the combination of tenoscopy and an early return to therapeutic hand walking during recuperation was found to reduce adhesion formation and improve the overall outcome.

Frees, K.E.; Lillich, J.D.; Gaughan, E.M.; et al. Journal of the American Veterinary Medical Association, 220 (12), 1823-1827, 2002