Surgical treatment including gentamicin-impregnated collagen sponge implantation of a chronic sinus tract of the superficial digital flexor tendon in a Hannoverian mare

An 18 months old Hannoverian mare was presented with an approximately 8-week old, non-healing focal wound in the left mid metatarsal region and severe left hind limb lameness at a walk (grade 4/5). Ultrasonography revealed a sinus tract between the skin and the superficial digital flexor tendon (SDFT) and a diffuse chronic tendonitis of the SDFT. Surgical en bloc resection of the sinus tract and the affected SDFT tissue was performed, and two collagen sponges (size 5cm×5cm×0.5cm) consisting of 70mg equine tendon collagen impregnated with 50mg gentamicin sulfate (GENTA-COLLresorb®, Resorba Medical GmbH, Nürnberg, Germany) were implanted into the wound prior to closure in 3 layers. A half limb cast was applied for 14 days followed by 4 days of a splint bandage. The wound healed by primary intention and the horse was discharged 4 weeks post operatively. Follow up examinations 6 and 24 month after discharge revealed excellent wound healing and soundness. Seven and 14 years after surgery the horse was still successfully used as pleasure riding horse as intended.