Lateral approach for arthrocentesis of the distal interphalangeal joint in horses.

The research paper investigates the use of a lateral approach for arthrocentesis (joint aspiration) of the distal interphalangeal (DIP) joint in horses, identifying anatomical landmarks for this approach and assessing the risk of inadvertently entering other synovial structures.

Methodology

• The researchers carried out a prospective study on the forelimbs of 8 cadavers and 12 live horses.
• Anatomic preparations were studied to identify landmarks for the lateral approach to DIP joint aspiration.
• Positive-contrast arthrography, a test using radiographic contrast media, was used to identify which structures were accessed during this approach.

Results

• The identified landmarks for the lateral approach included a depression in the proximal border of the lateral ungular cartilage and the palmar border of the middle phalanx.
• The test using positive-contrast arthrography revealed that the lateral approach resulted in the exclusive deposition of contrast material in the DIP joint in only 13 out of 20 limbs.
• In contrast, the use of the conventional dorsal approach resulted in exclusive deposition in the DIP joint in all 20 limbs.

Conclusions

• Though less precise than the dorsal approach, the lateral approach presents an alternative method for accessing the DIP joint in horses.
• However, the researchers caution that this approach carries a risk of accidentally entering other synovial structures.
• Despite this risk, the lateral approach may still provide a valuable additional entry point for through-and-through lavage (fluid cleaning of a body cavity), and for arthroscopic access to the joint’s palmar aspect.