Penetrating injuries to the frog (cuneus ungulae) and collateral sulci of the foot in equids: 63 cases (1998-2008)

Objective-To determine the outcome of penetrating injuries to the central region of thefoot in equids and identify factors that may affect treatment and outcome.Design-Retrospective case series.Animals-63 equids (61 horses, 1 pony, and 1 mule).Procedures-Records of equids incurring puncture wounds through the frog (cuneus ungulae)or collateral sulci of the foot between 1998 and 2008 were reviewed. Evaluated factors that werehypothesized to affect outcome included signalment, degree of lameness, foot affected, durationbetween injury and admission, and treatment. Injuries were graded from 1 (< 1 inch; involvingsuperficial corium only) to 4 (involving a synovial structure) on the basis of severity of penetrationas determined by radiographic evidence or findings on synoviocentesis at the time of admission.Results-Overall, 60% (38/63) of equids returned to soundness. Thirteen equids were euthanizedon the basis of synovial structure involvement and financial constraints. Of 35 equidsthat were treated conservatively, which may have included undergoing a surgical procedurewith the horse standing, 32 (91.4%) returned to their previous level of soundness. Fifteenequids underwent surgical treatment under general anesthesia, of which 6 (40%) becamesound for intended use. Ten of 34 (29%) equids with synovial structure involvement regainedsoundness. Equids treated earlier after injury had a better prognosis. Equids with a hind footinjury had a more favorable outcome than those with a forefoot injury.Conclusions and Clinical Relevance-Results suggested that penetrating injuries locatedcentrally in the foot of equids without involvement of a synovial structure have a favorableprognosis, especially if managed early. Penetration of a synovial structure provided a poorprognosis.