Factors associated with survival and racing performance of 114 Thoroughbred foals with septic arthritis compared with maternal siblings (2009‐2015)

Abstract

Background: There is little consensus on factors associated with survival in foals with septic arthritis and limited data on long-term racing performance of Thoroughbred foals treated for septic arthritis. A more thorough understanding of short-and longterm outcome is necessary to help inform owners, and subsequently guide treatment.Objectives: To investigate factors associated with survival, and to analyse racing performance of foals with septic arthritis compared with their maternal siblings. Study design:Retrospective cohort and a case-control study.Methods: Veterinary clinical records of Thoroughbred foals ≤180 days old that underwent arthroscopic, cannulae or through-and-through needle lavage for the treatment of septic arthritis between 2009 and 2015 were reviewed. Data included signalment, and clinicopathological information. The dam's foaling records were reviewed and the lifetime racing records were obtained for affected foals and two of their maternal siblings. Logistic regression analysis was used to determine factors associated with survival to discharge or racing. Comparisons between treated foals and their maternal siblings were made.Results: Ninety (78%) of 115 foals diagnosed with septic arthritis were discharged alive. Foals <26 days old at the time of admission were five times less likely (P = .003) and foals with concurrent multisystemic disease were six times less likely (P = .02) to be discharged alive. Sixty (67%) foals discharged alive started in ≥1 race, and there was no difference in the proportion of foals that started in a race or racing performance between foals treated for septic arthritis and their maternal siblings. Main limitations:Retrospective study design, limited number of foals with multiple joint involvement and failure to accurately record duration of clinical signs.Conclusions: Foals treated for septic arthritis at the Scone Equine Hospital, New South Wales, Australia had a good prognosis for survival, and for this cohort, foals that survived to discharge had a similar ability to race as their maternal siblings.

Synovial Fluid Analysis and Microscopic Assessment of Macrophage Quantities and Morphology in Equine Septic Arthritis

“…Survival rates in foals with SA in previous studies are widely diverging 4 . While one study reports that 56.6 % (47/83) were discharged alive, other publications determined survival rates of 78 % (90/115) 26 or 80 % even (48/60) 27 . Dischargement of hospital is considered as 5 times less likely if foals were aged < 26 days at time of admission 26 .…”

“…While one study reports that 56.6 % (47/83) were discharged alive, other publications determined survival rates of 78 % (90/115) 26 or 80 % even (48/60) 27 . Dischargement of hospital is considered as 5 times less likely if foals were aged < 26 days at time of admission 26 . Foals in the present study had a mean age of 24.5 days, probably influencing the present survival rate of 58 %.…”

“…While one study reports that 56.6 % (47/83) were discharged alive, other publications determined survival rates of 78 % (90/115) [26] or 80 % even (48/60) [27]. Dischargement of hospital is considered as 5 times less likely if foals were aged < 26 days at time of admission [26]. Foals in the present SFM relative concentrations did not considerably differ in horses being euthanized (SFM = 7 %), discharged moderately lame (SFM = 8 %) or not lame/mildly lame (SFM = 9 %), thus SFM proportions should not be used to make a statement about the prognosis.…”

Prognosis for survival to discharge and racing performance in Thoroughbred foals treated for single joint septic arthritis (2009–2016)

“…2,5,11,12 Studies have found decreased survival with multiple joint involvement compared with a single affected joint. [11][12][13][14] Previous data have suggested that septic arthritis in the Thoroughbred foal significantly reduces the likelihood of race when compared with maternal sibling controls. 3 However no significant difference in racing performance was found in the recent study by O'Brien et al 14 when comparing Thoroughbred foals with septic arthritis to their maternal siblings.…”

“…[11][12][13][14] Previous data have suggested that septic arthritis in the Thoroughbred foal significantly reduces the likelihood of race when compared with maternal sibling controls. 3 However no significant difference in racing performance was found in the recent study by O'Brien et al 14 when comparing Thoroughbred foals with septic arthritis to their maternal siblings. To the authors' knowledge, no previous studies have evaluated the specific case where only one joint is affected without obvious evidence of active or historical systemic sepsis or other comorbidities not associated with the affected joint.…”