Comparison of the cranial and a new lateral approach to the femoropatellar joint for aspiration and injection in horses.

The study compares a new method that uses a lateral approach to the femoropatellar joint in horses for fluid aspiration and injection, with the traditional cranial approach. The findings showed that the lateral approach yielded more fluid and was less likely to damage the articular surface of the joint.

Research Purpose

• The purpose of the research was to investigate a new technique for aspiration and injection into the femoropatellar joint (the knee joint) in horses. The traditional technique, which involves a cranial (frontal) approach to the joint, often results in signs of discomfort in the horses and sometimes cannot collect a sufficient volume of synovial fluid.

Research Methodology

• The study compared the two techniques – the cranial approach and the new lateral (from the side) approach – in 12 horses.
• The amount of fluid obtained, its properties (color, nucleated cell count, red blood cell count, total protein), and injury to the articular cartilage (the smooth, white tissue that covers the ends of bones where they come together to form joints) were examined for both approaches.

Key Findings

• The study found that the lateral approach acquired significantly more fluid (around 2.0 ± 0.5 ml) than the cranial approach (approximately 0.9 ± 0.2 ml).
• The fluid’s characteristics were not affected by the method of extraction; no significant differences were found in color, nucleated cell count, red blood cell count, or total protein between the two types.
• The greatest difference was observed in the injury score to the articular cartilage, which was significantly lower with the lateral approach (average score 0.3 ± 0.3) than with the cranial one (average score 1.3 ± 0.4).
• Moreover, only one joint (8%) was injured during the lateral approach, compared with eight joints (67%) in the cranial approach.

In conclusion, the study suggests that a lateral approach for aspiration and injection in the femoropatellar joint is safer and more efficient than the conventional cranial method, yielding more fluid and less likely leading to joint injury.