Resection of Grade III cranial horn tears of the equine medial meniscus alter the contact forces on medial tibial condyle at full extension: an in-vitro cadaveric study.

The research article discusses a study that assesses changes in the force distribution on the horse’s knee joint (medial tibial condyle) following the removal (resection) of severe tears (grade III) in the inner knee cushion (medial meniscus). The findings indicate that such a resection leads to increased pressure in specific areas of the medial tibial condyle, particularly when the equine knee (stifle) is fully extended.

Research Overview

The study is a scientific investigation that uses equine cadavers to observe the impact of severe tears in the medial meniscus – the crescent-shaped disc that acts as a cushion for the knee joint, and what happens if this tear is surgically removed. The researchers focus on changes in pressure distribution on the tibial condyle, which is a rounded portion at the end of the tibia (lower leg bone) that interacts with the femur (thigh bone) to form the knee joint.

Methodology

• The study uses six equine stifles (knee joints) procured from the cadavers of horses.
• These stifles are mounted in a materials testing system, with electronic pressure sensors inserted between the medial tibial condyle and the medial meniscus.
• The specimens are then subjected to a load parallel to the length of the tibia at four different stifle angles (130°, 140°, 150°, and 160°) while recording the peak pressure and the contact area from the system’s generated maps.
• The testing process is repeated once after a grade III cranial horn tear is artificially created in the medial meniscus and once more after this artificially created tear is surgically removed or ‘resected’.

Findings

• The study records a significantly smaller contact area at maximum extension (160° angle) in the intact specimens when compared to the other angles.
• Creating a grade III cranial horn tear did not alter the pressure or contact area measurements significantly at any angle when compared to the intact specimens.
• Surgically removing this tear significantly increased the peak pressure in the central region of the medial tibial condyle at maximum extension (160° angle) in comparison to both the intact and torn specimens.

Conclusion

The researchers conclude that resecting grade III cranial horn tears in the medial meniscus leads to a concentrated increase in pressure in a specific region of the medial tibial condyle when the equine stifle is fully extended (at 160°). These findings have implications for post-surgery rehabilitation and the long-term health of the horse’s leg joint.