Multicenter study investigating long-term survival after synovial lavage of contaminated and septic synovial structures in horses presented to 10 UK referral hospitals.

Objective: To report the long-term survival of adult horses that were subjected to synovial lavage for treatment of contaminated and septic synovial structures.

Study design: Multicenter, prospective observational trial.

Animals: Horses (n = 240) presented for synovial sepsis at 10 UK referral centers.

Methods: Data for horses presented for treatment of synovial sepsis were collected over a 15 month recruitment period. Owners were contacted a minimum of 365 days after surgery using a structured client interview to assess long term survival. Descriptive statistics, and univariable and Cox proportional hazards models for postoperative survival time were developed.

Results: Survival to discharge was 228/240 (95%) and overall long-term survival was 89.4% (185/207). Unknown cause of injury (p = .017), increasing duration of surgery (p = .003), increasing weight (p = .008), forelimb injuries (p = .027), and type of synovial structure (p = .008) were found to be associated with death using Cox proportional hazards models.

Conclusion: This study provides information on risk factors associated with survival and death after treatment for synovial sepsis at referral hospitals in the UK. Survival to discharge and long-term survival was excellent. Heavier horses, injuries affecting the forelimbs, tendon sheaths and bursae were associated with poorer long term outcomes. Longer duration of surgery was also found to be associated with a worse prognosis.

Clinical significance: These findings help to provide prognostic information for owners and veterinarians treating horses with synovial sepsis.