Septic Synovitis and Osteomyelitis in Foals: Current Situation in a French Referral Hospital and Value of Computed Tomography for Diagnosis and Treatment.

Septic synovitis and osteomyelitis are common infections in young foals that can affect bones and joints. This study evaluates cases from a French referral hospital and examines how computed tomography (CT) scans aid in diagnosis and treatment.

Study Overview and Objectives

• Analyzed cases of septic synovitis and osteomyelitis in foals younger than 6 months.
• Conducted at a single French referral hospital.
• Retrospective descriptive study involving 65 foals.
• Aimed to describe clinical presentation, management, and outcomes.
• Evaluated the usefulness of computed tomography (CT) in detecting lesions and guiding treatment.

Participant Details and Survival Outcomes

• Total foals included: 65.
• Survival to discharge: 46 foals (71%).
• Presence of osteomyelitis alone did not significantly reduce survival chances (p=0.16).
• Presence of umbilical infection or infection with a specific pathogen also did not significantly impact survival.
• Increased risk of nonsurvival if:
  • Multiple infection sites were involved (p=0.007, odds ratio (OR) = 5.80).
  • Bony lesions visible on initial radiographs (p=0.03, OR = 3.47).

Frequency and Distribution of Osteomyelitis

• 66% of foals (43 out of 65) had osteomyelitis, demonstrating a high frequency.
• Osteomyelitis was detected in multiple regions of the skeleton.
• Some cases had osteomyelitis with septic synovitis, others either condition alone.

Role and Impact of Computed Tomography (CT)

• CT scans were used as part of the diagnostic process in some foals.
• CT did not significantly affect overall survival (p=0.27).
• Crucially, CT identified osteomyelitis lesions in 37.2% of cases (16 out of 43) where radiographs showed no abnormalities.
• CT scans helped reveal “radiographically silent” lesions early.
• These findings support CT as a valuable tool for early diagnosis and precise treatment targeting.

Clinical and Veterinary Implications

• Positive prognosis for orthopaedic infections in foals, especially if infection is limited to one site.
• Multiple infection sites and visible bone lesions on radiographs correlated with worse outcomes.
• CT scans enhance the ability to detect hidden infections, potentially improving management strategies.
• Overrepresentation of Gram-positive bacterial infections suggests parallels with human pediatric orthopedic infections, which may inform comparative treatment approaches.
• Overall, the study highlights the importance of thorough diagnostic imaging and supports advanced imaging techniques like CT for managing complex infections in young foals.