Haematogenous septic arthritis, physitis and osteomyelitis (SAPO) is a potentially debilitating or even life-threatening disease entity encountered in foals of all ages between birth and approximately 7 months old. Correct, and complete, diagnosis and successful treatment require collaboration between specialties including medicine, anaesthesia, diagnostic imaging, surgery and rehabilitation services. However, in order to succeed, it is important that all specialties have an overall knowledge of all aspects of the disease complex. Therefore, the aim of this review is to give an overview of aetiology, presenting complaints, clinical findings, diagnostic imaging, treatment, rehabilitation and prognosis. Part one deals with all aspects of aetiology and how to make a diagnosis. Part two deals with all aspects of treatment, rehabilitation and prognosis. MethodsSince this is considered a tutorial review, the authors aim to provide a selected review of the most relevant literature combined with the authors' experiences on the subject. Consequently, it should not be seen as a systematic review, and the reference list may not be exhaustive. Classification, aetiology and pathogenesisSAPO represents slightly different presentations of infection in the joint or the surrounding bone occurring as sequelae to bacteraemia or even sepsis in neonatal or young foals. Despite the differences, they share similarities in presentation that can make discrimination challenging (Firth et al. 1980;Firth 1983). Haematogenously disseminated bacteria originate

Summary Haematogenous septic arthritis, physitis and osteomyelitis are manifestations of a potentially debilitating or even life‐threatening disease entity encountered in all types of foals from neonates to approximately 7 months of age. Correct and complete diagnosis and successful treatment requires collaboration across specialties; medicine, anaesthesia, diagnostic imaging, surgery, and rehabilitation. However, in order to succeed it is important that all specialties have an overall knowledge of all aspects of the disease complex. Therefore, the aim of this review is to give an overview of aetiology, presenting complaints, clinical findings, diagnostic imaging, treatment, rehabilitation and prognosis.