In horses, flexor tendon lacerations are serious injuries that alter limb conformation and impair limb function. During evaluation of a laceration, the involvement of the tendon sheath should be recognized to allow appropriate treatment of the synovial structure and tendon. In flexor tendon lacerations, the synovial structure that is most often affected is the digital synovial sheath, which surrounds the superficial and deep digital flexor tendons. Because the tendon sheath is in a superficial location at the caudal, medial, and lateral aspects of the limb, penetration is likely even with minor lacerations. Successful treatment depends on accurately assessing the damage, identifying the tendon or tendons that have been transected, and recognizing whether a tendon sheath has been invaded. Factors that determine appropriate treatment of tendon lacerations include the time elapsed since injury, contamination or infection of the wound, involvement of synovial structures, the location of the injury, and the structures involved. Treatment options include whether to close the wound, whether to suture the tendons, and what kind of external support to provide during healing. With appropriate treatment, 60% to 80% of affected horses should survive and be able to be ridden.
