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

BACKGROUND: Haematogenous septic arthritis is a major cause of morbidity and mortality in foals. Previous research has demonstrated a variable prognosis for athletic performance in foals diagnosed with septic arthritis. OBJECTIVE: To determine the racing prognosis for Thoroughbred foals, 6 months of age or less with single septic joint of presumed haematogenous origin without recognised systemic sepsis or other serious comorbidity compared with a group of maternal sibling controls. STUDY DESIGN: Retrospective cohort study. METHODS: Data were collected from Rood and Riddle Equine Hospital in-patient records from 2009 to 2016. Parameters evaluated included: diagnostic tests, therapeutic regimens, final diagnosis and outcome. Racing records were obtained from a public archive for cases and two maternal siblings. Univariable analyses of categorical variables were conducted. RESULTS: Ninety-five cases of Thoroughbred foals 6 months of age or less were included in this study. The last measured synovial cell count prior to hospital discharge or euthanasia (OR 0.5, p value 0.002, 95% CI: 0.3-0.8) was an indicator of poor prognosis for survival to discharge. Overall, the prognosis for survival was high (93%). Total winnings per career were the only statistically significant racing performance variable between cases and paired controls (IRR 0.7, p value, 0.05, 95% CI: 0.5-0.99). MAIN LIMITATIONS: Retrospective study, evaluation of one regional population, potential for unknown prior exclusionary treatment on farm, unknown chronicity, no data on acute phase proteins and proportion of neutrophils of synovial fluid and unknown medical records of controls. CONCLUSIONS: While total winnings were reduced compared with maternal siblings, Thoroughbred foals with single joint septic arthritis have a favourable prognosis for both survival and starting in a race.

CONTEXTO: Artrite séptica hematogênica é a maior causa de morbidade e mortalidade em potros. Estudos prévios demonstraram um prognóstico variável para a performance atlética de potros diagnosticados com artrite séptica. OBJETIVOS: Determinar o prognóstico atlético de potros Puro Sangue Inglês, de seis meses de idade ou menos, com uma única articulação séptica de origem presumida hematogênica, sem nenhum sinal sistêmico de sepse reconhecido e sem outras comorbidades sérias, comparados com um grupo de irmãos maternos como controle. DELINEAMENTO DO ESTUDO: Estudo coort retrospectivo. MÉTODOS: Dados foram coletados de pacientes do Rood and Riddle Equine Hospital de 2009 a 2016. Os parâmetros avaliados incluíram: testes diagnósticos, tratamentos, diagnóstico final e sobrevivência à alta hospitalar. Os dados das corridas foram obtidos do equibase.com para os casos clínicos e dois irmãos maternos. Análise univariável de variantes categóricas foi realizada. RESULTADOS: Noventa e cinco potros Puro Sangue Inglês de seis meses de idade ou menos foram incluídos nesse estudo. A última mensuração da contagem de células no líquido sinovial antes da alta hospitalar ou eutanásia (OR 0.5, p-value 0.002, 95% CI: 0.3 a 0.8) foi um indicador estatisticamente significante de prognóstico ruim para sobrevivência. O prognóstico para sobrevivência foi alto (93%). O ganho total por carreira foi o único fator estatisticamente diferente entre casos e controles (IRR 0.7, p-value, 0.05, 95% CI: 0.5 a 0.99). PRINCIPAIS LIMITAÇÕES: Estudo retrospectivo, avaliação de uma população em uma única região, chances de um tratamento desconhecido na fazenda, cronicidade desconhecida, ausência de resultados de proteínas de fase aguda e concentração de neutrófilos no líquido sinovial, e ausência de controles dos registros médicos. CONCLUSÕES: Apesar do ganho total ser menor quando comparado com os irmãos maternos, potros Puro Sangue Inglês com uma única articulação séptica têm um prognóstico favorável para sobrevivência e para iniciar uma corrida.

Comparative results of 3 treatments for medial femoral condyle subchondral cystic lesions in Thoroughbred racehorses.

OBJECTIVES: To compare 3 different methods for treatment of medial femoral condyle (MFC) subchondral cystic lesions in Thoroughbred horses <24 months old based on the criterion of ability to race post-treatment. STUDY DESIGN: Retrospective cohort study. ANIMALS: Thoroughbreds (n = 107, age < 24 months) diagnosed with MFC subchondral cystic lesions. METHODS: Medical records between January 2004 and December 2017 were reviewed. Three treatment methods were used in these horses during that time frame: arthroscopic debridement, intralesional autologous mesenchymal stem cell (MSC) injection, and intralesional corticosteroid injection. The outcome evaluated was the ability to compete in a pari-mutuel race. RESULTS: Seventy-eight of 107 Thoroughbreds (73%) raced post-treatment; 41/57 (72%) of horses treated by arthroscopic debridement raced; 16/19 (84%) of horses treated with intralesional MSCs raced; 21/31 (68%) of horses treated with intralesional corticosteroids raced. There was no difference between groups in the ability to start a race. Sex, limb affected, and lesion size also had no effect on the ability to start a race. There was a trend for increasing lesion size reducing the probability of racing. CONCLUSIONS: Seventy-three percent of the horses raced, but there was no difference in the ability of unraced Thoroughbreds to race after treatment of MFC subchondral cystic lesions with arthroscopic debridement, intralesional mesenchymal stem cells, or intralesional corticosteroids. CLINICAL SIGNIFICANCE: The 3 reported treatment options may be considered for treatment of MFC subchondral cystic lesions with a good prognosis for racing post-treatment. Owners should be advised that increasing lesion size decreases the probability of racing.

Clinical outcomes after colopexy through left ventral paramedian incision in 156 thoroughbred broodmares with large colon disorders (1999-2015).

OBJECTIVE: To describe a technique for colopexy via a left ventral paramedian incision and report postoperative clinical outcomes. STUDY DESIGN: Retrospective case series. ANIMALS: One hundred fifty-six thoroughbred broodmares treated with a colopexy through a left ventral paramedian incision between 1999 and 2015. METHODS: Medical records were reviewed for postoperative complications and survival to discharge. The survival rate at 1 year after surgery was based on the medical record, progeny record, or client telephone conversation. Progeny records were reviewed to assess reproductive performance. T tests, χ2 tests, logistic regression, and Kaplan-Meier survival curves were used to identify prognostic factors. RESULTS: The rates of postoperative recurrence of large colon volvulus and colon rupture were 1.2% and 3%, respectively. Ninety-three percent of mares that were treated were discharged alive from the hospital, and 78% were alive 1 year after surgery. The diagnosis of 1 of the following complications increased the risk of death within 1 year: systemic inflammatory response syndrome (SIRS), diarrhea, and/or thrombophlebitis (odds ratio [OR] 4.76). Sixty-six percent of mares that were pregnant at the time of colopexy and discharged alive from the hospital produced a live foal. The percentage of live foals produced each year that the mare was bred after colopexy was 67%. CONCLUSION: Thoroughbred mares treated with colopexy via a left paramedian incision had a good prognosis for survival and continued use as a broodmare. SIRS, diarrhea, or jugular thrombophlebitis affected long-term survival in this population. CLINICAL SIGNIFICANCE: Colopexy via a left paramedian incision is a suitable alternative to colopexies requiring a second incision or creating adhesions between the colon and the linea alba in thoroughbred mares.

Radiotherapy of a recurrent ossifying fibroma in the paranasal sinuses of a horse.

A 7-year-old female Thoroughbred was admitted with a history of labored breathing, stridor, and exercise intolerance. Examination revealed a mass in the left paranasal sinuses that was determined to be an ossifying fibroma. Initial treatment consisted of surgical removal of the mass alone; however, the mass recurred 9 months after surgery. The mass was again removed, and adjunctive radiotherapy consisting of 3,000 cGy of cobalt radiation was administered. This time, the tumor did not recur for > 6 years. A third surgery was performed to remove the mass, and adjunctive radiotherapy consisting of 4,000 cGy of photon beam radiation from a linear accelerator was administered. The mass did not recur during the subsequent 3 years. Ossifying fibromas are uncommon tumors that frequently recur if incompletely excised. Results in this horse suggest that adjunctive radiotherapy may delay or prevent tumor recurrence in affected horses.