Factors associated with prolonged treatment days, increased veterinary visits and complications in horses with subsolar abscesses

Abstract

There is a lack of epidemiological studies about equine subsolar (hoof) abscesses even though they are among one of the most common causes of acute, severe lameness. The goals of this study were to (1) describe the equine subsolar abscess patient population of the University of Pennsylvania’s New Bolton Center’s Field Service and (2) to determine the factors that are associated with increased veterinary visits, prolonged treatment and complications. Descriptive statistics were performed on data collected from 160 cases of equine subsolar abscess. Inferential statistics were performed on a subset of those cases. No significant results were identified in relation to an increased number of veterinary visits. Poisson regression of days of treatment revealed that abscesses diagnosed in the summer (incidence rate ratio (IRR)=9.42, P<0.001) and abscesses found at the coronary band (IRR=3.21, P<0.001) were more likely to be treated for longer. Presence of a draining tract (IRR=0.73, P=0.017) and a higher lameness (IRR=0.30, P=0.01 for grade 3, IRR=0.1, P<0.001 for grades 4 and 5) score at presentation resulted in shortened treatment times. Abscesses affecting multiple portions of the digit were associated with an increased chance of complication. The study presented here is the first retrospective study on subsolar abscesses to the authors’ knowledge.

Foot abscessation in horses

“…The seasonality of the occurrence of foot abscessation in this study 1 is interesting, as it is a widely held belief that foot abscesses are more common in the wet seasons. The majority (more than 59 per cent) of the abscesses observed in this study were first evaluated between June and November, with horses diagnosed in the summer undergoing a longer period of treatment (almost a 9.5 fold increase) compared with those where the diagnosis was made in winter.…”

“…Many practitioners consider antibiotics contraindicated because administration may prolong clinical signs, but antibiotic therapy may be indicated if there is swelling and infection of the coronary band and subcutaneous tissues of the pastern region 6 . The study by Cole and colleagues 1 did not appear to support this widely held belief that antibiotic treatment in foot abscessation prolongs clinical signs. However, if there are no complications associated with the foot abscess and adequate drainage is established, it can be argued that antibiotics are contraindicated based on current guidelines for the responsible use of antibiotics 7…”

“…An epidemiological study by Cole and colleagues 1 is summarised on p 251 of this issue of Vet Record . In this paper, the authors aim to describe the clinical features of equine subsolar abscess cases from the clinical population of their practice and to determine the factors that are associated with increased number of veterinary visits, prolonged treatment and complications.…”

“…The study by Cole and colleagues 1 showed that subsolar abscesses are more common in forelimbs, with the right forelimb being the most commonly affected. This is in agreement with a previous study 2 showing that the right forefoot was most commonly affected.…”

“…Cole and colleagues 1 reported that the presence of a draining tract and higher lameness scores on initial presentation were found to result in shortened treatment times. They suggest that this is likely to be because horses that present with severe lameness often have a mature abscess that is close to rupture and drainage, and this would seem reasonable.…”