Complications during treatment of traumatic disruption of the suspensory apparatus in Thoroughbred horses.

Abstract

A total of 19 Thoroughbred horses were treated for traumatic disruption of the suspensory apparatus, using either external support of the injured limb, removal of fractured proximal sesamoid bone fragments, metacarpophalangeal arthrodesis, compression screw fixation of the fractured proximal sesamoid bones, application of a cast-brace attached to a transfixation pin inserted through the third metacarpal bone, or combinations thereof. Major complications during the treatment of traumatic disruption of the suspensory apparatus were infection (9 of 19 horses, 47%), large cast sores (10 of 14 treated horses, 71%), laminitis (7 of 19 horses, 37%), and orthopedic implant failure or loosening (4 of 6 treated horses, 67%), which led to euthanasia in 16 of 18 cases with complete follow-up information. Increased pain and lameness signaled the development of such complications. In 7 of 9 cases with infection confirmed by microbiologic culture, the horse had received surgical treatment; in 6 of those 7 cases, the infection involved the surgical site. Postoperative wound infection developed in 4 of 7 cases when the surgery was performed within 18 days of injury. In 3 cases, septic metacarpophalangeal arthritis developed, but it was unrelated to surgical procedures. Implant failure or loosening and infection led to euthanasia in 5 of 6 horses treated by internal fixation to stabilize the metacarpophalangeal joint. Three of 6 attempts to perform metacarpophalangeal arthrodesis by application of a bone plate to the dorsal aspect of the joint resulted in implant failure after 45 to 101 days. Major complications did not develop in 2 horses that were treated successfully.