SAEVA Proceedings 2014 | Page 39

46TH  ANNUAL  CONGRESS  OF  THE  SAEVA        SKUKUZA      16-­‐20  FEBRUARY  2014   39     How to manage septic arthritis caused by distal limb lacerations Mahne A1* 1 Section Equine Surgery, Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110. Distal limb lacerations are a common cause of septic arthritis (or septic tenosynovitis) in the horse. This is a life threatening condition and necessitates prompt diagnosis and early and aggressive treatment. The following can aid in the diagnosis of synovial structure involvement in a distal limb laceration: • • • • • • Severe lameness (unless the joint is open causing leaking of synovial fluids) Digital exploration of the wound, performed aseptically Pressurising the wound from an arthrocentesis site as far away from the wound as possible Radiographs/Ultrasound/Scintigraphy Synovial fluid analysis, evaluating colour, viscosity and cytology: Normal joint fluid Septic joint fluid Nucleated Cell Count (NCC) % Neutrophils < 1 x 109 cells/L > 30 x 109 cells/L < 10 % of nucleated cells > 80 % of nucleated cells Total protein < 25 g/L > 40 g/L Bacterial culture (this takes too long to wait for the results before initiation of therapy. Also, ~ 50 % of case with a septic joint will have a negative culture). Treatment for cases of septic arthritis includes arthroscopic flush and debridement, arthrotomy, through-and-through needle lavage (usuall y not very effective due to fibrin in joint) and systemic and local antimicrobial therapy. Local antimicrobial therapy includes regional limb perfusion, intra-articular antimicrobial injection and intra-articular antimicrobial constant rate infusion. Adult horses treated for septic arthritis has a fair prognosis for survival and a guarded prognosis for return to an athletic career. Factors associated with a negative outcome are involvement of tendon or bone, involvement of multiple synovial structures, osteomyelitis and increased duration of clinical signs before initiation of treatment.   39