Postmortem lesions in the intercarpal ligaments of the equine midcarpal joint.

The study investigated damages to specific ligaments in the midcarpal joint of horses that had no history of carpal joint disease. It found that such damages are common, especially in racing horses, but don’t usually lead to serious clinical issues. The research also observed a significant variation in the size of the dorsomedial intercarpal ligament, especially in 2-year-old horses.

Research Objectives and Methods

• The research objective was to determine the frequency of damage to a specific ligament, the medial palmar intercarpal ligament (MPICL), within the midcarpal joint of horses without a history of carpal joint disease. The team also aimed to obtain the range of sizes of another ligament, the dorsomedial intercarpal ligament (DMICL).
• Cadaver limbs from 72 horses with no history of carpal joint disease were collected, from which 142 midcarpal joints were dissected. The researchers examined the MPICL and DMICL, recording measurements with a digital micrometer.

Research Findings

• Tears in the MPICL were present in most of the examined joints from horses aged 2 years and older. However, complete rupture of the dorsolateral and dorsomedial bundles of the ligaments was not observed.
• The frequency and severity of tearing increased significantly with age, but was not found in foals less than 4 months old.
• Notably, tearing was significantly more severe in racing standardbreds as compared to racing thoroughbreds. Despite this, there was no significant difference found between racing and non-racing horses.
• Regarding the DMICL, its lateromedial thickness also increased significantly with age, with sizes ranging from 0.4 mm to 2.6 mm in horses 2 years and older. Just like for MPICL, the thickness was significantly more in racing standardbreds than in racing thoroughbreds. However, there was no significant difference found between racing and non-racing horses.

Conclusions

• The research concluded that damages to the dorsolateral bundle of the MPICL are a common occurrence in horses older than 1 year, but usually do not have serious clinical impact.
• Complete rupture of both the dorsolateral and dorsomedial bundles is rare in horses without a history of midcarpal joint disease.
• Finally, the team observed that the size of the DMICL can vary significantly, with this variation being most noticeable in 2-year-old horses.