Lameness due to pain associated with the distal interphalangeal joint: 45 cases.

This study presents a comprehensive examination of 45 horses that exhibited lameness that responded to anesthetic treatment of the painful distal interphalangeal joint, outlining the clinical and radiographic characteristics of the cases as well as their reactions to treatment methods.

Key Findings

• The research looked at lameness linked to discomfort in the distal interphalangeal (DIP) joint, which was improved through intra-articular anaesthesia. Lameness was typically unilateral, and treatments didn’t work for cases involving bilateral lameness.
• Even though several horses possessed poor limb foot conformation, the majority did not present local clinical signs that would suggest DIP joint involvement.
• Palmar digital nerve blocks often mitigated or eliminated lameness. However, some horses needed palmar nerve blocks to completely get rid of lameness. The difference in response did not impact the treatment results.

Signs and Diagnostics

• After intra-articular anaesthesia of the DIP joint, lameness usually ceased within 5 minutes. A disease prognosis tends to be poor when lameness only partially improves or response is slow after this treatment.
• All the horses lacked radiographic signs consistent with navicular disease. Radiographic changes in the DIP joint, if present, were usually only visible in lateromedial views and were found in less than a third of the horses.

Treatment and Outcomes

• The success rate was low when treating cases that had radiographic abnormalities. In horses with no detectable radiographic changes, the response to corrective trimming and shoeing and the intra-articular application of sodium hyaluronate was inconsistent. There were no clear indicators that could predict the treatment outcomes.
• Only about 30 per cent of the horses responded positively to the treatments. Further treatment of those that remained lame did not prove beneficial, even after intra-articular administration of polysulphated glycosaminoglycans or lengthy resting periods of up to nine months.