Management of Wounds with Equine Joint Involvement
By Kathryn M. Slaughter-Mehfoud, DVM, MPH, Veterinary Surgeon based out of Louisville, Kentucky
Whether it’s a large laceration or a small puncture wound over a joint, immediate diagnosis and aggressive treatment of wounds involving joints is imperative to decrease morbidity and mortality of our equine patients. All potential joint infections should be considered emergencies and time should be taken to accurately confirm joint involvement and initiate appropriate therapy.
When the veterinarian is presented with a patient that has a wound with potential joint involvement, the first step is to confirm the wound has communication with the synovial cavity. After appropriate sedation of the patient, the practitioner should palpate the wound using sterile gloves. Digital palpation alone may be sufficient for diagnosis. If palpation of the wound is inconclusive, aseptic distension of the joint with sterile saline is recommended. If there is communication with the synovial cavity and the wound, sterile saline should be visualized exiting the wound. Other diagnostic techniques which are helpful in diagnosing synovial involvement include radiographs with a sterile probe or contrasting agent.
Once synovial involvement has been confirmed, aggressive therapy is recommended. The three main techniques for preventing bacterial infection in wounds are: 1) appropriate wound cleansing and debridement, 2) appropriate bandaging protocols, 3) and appropriate use of antimicrobials.
For wound cleansing and debridement, thoroughly remove all debris using sterile saline. I recommend using sharp debridement of the wound edges with a scalpel blade, known as “freshening the wound edges.” Following sharp debridement, I follow up with mechanical debridement using sterile saline. I recommend copious lavage of the wound with sterile saline using a 19-gauge needle of a 35 mL syringe. Remember, the solution to pollution is dilution!
The wound should be bandaged and secured in a way which prevents further contamination. Elastikon is expensive, but so worth the added cost to prevent further dirt and debris from getting under the bandage. Initially, the bandage should be changed daily so the healing process can be closely monitored. Without initial daily bandage changes, signs of improper healing can be overlooked, which increases morbidity and mortality.
Ideally, horses having wounds with confirmed joint involvement should be hospitalized for rigorous antimicrobial therapy. I strongly recommend the use of broad-spectrum antimicrobials gentamicin and penicillin. However, if these antimicrobials aren’t an option for the client, oral broad-spectrum antimicrobials should be administered. In addition, regional limb perfusions with antimicrobials are strongly recommended for 3-5 days following the initial injury.
The question of when to refer these cases is critical to the horse’s future athletic use and survival. Gold standard care is to arthroscopically lavage these compromised joints followed by hospitalization with the use of injectable antimicrobials and regional limb perfusions. However, this is a large financial commitment for the owner. I always recommend offering the gold standard care, which is referral to a surgical facility, but I recognize this isn’t feasible for the majority of horse owners. If the wound will require suturing of the joint capsule, referral is strongly encouraged, as this should be performed under the most sterile conditions. For small penetrating wounds in which finances don’t allow referral, we work with the budget we have to ensure the best outcome for the horse. Ultimately, owner compliance with regards to a clean environment, appropriate bandaging, and using antimicrobials at the prescribed dosage and dosing intervals will heavily influence the overall outcome for these complicated cases.