Comparison of three drilling techniques for carpometacarpal joint arthrodesis in horses.

This study explores and compares the effectiveness of three drilling techniques for fusing the carpometacarpal joint in horses, with results indicating that techniques 1 and 2 cause the most damage to cartilage and subchondral bone, potentially making them suitable for achieving joint fusion. In-depth evaluation of long-term results and effects (morbidity and efficacy) in live subjects is necessary.

Methodology

• The study utilized 15 cadaveric equine forelimbs, categorizing them into three groups to examine different drilling methods.
• Technique 1 used a 4.5 mm drill bit through four entry points in a fanning motion.
• Technique 2 employed a 5.5 mm drill bit through two entry points to create three nonfanned tracts.
• Technique 3 used a 4.5 mm drill bit, similar to the first technique, but with a three-drill approach.
• The carpometacarpal (CMC) joint was then disassembled after the drilling, and damage to the cartilage and subchondral bone was evaluated visually. Researchers also used gross and microradiographic examination with planimetry for a more thorough review.

Results

• The first technique resulted in considerable damage to the upper surface, but only minor damage to the subchondral bone on the lower surface.
• Technique 1 was found to inflict the most damage to the articular cartilage and subchondral bone compared to both three-drill tract methods. However, the difference in induced damage between techniques 1 and 2 were statistically insignificant.
• Damage resulting from Technique 3 was significantly less than that from techniques 1 or 2.

Conclusions

• The study concluded that techniques 1 and 2 resulted in the most cartilage and subchondral bone damage, with technique 2 causing a more balanced distribution of damage between the upper and lower joint surfaces.
• The researchers suggest technique 1 (fanning) and 2 (5.5 mm 3 drill tracts) may be preferred to achieve arthrodesis of the CMC joint.
• There is a need to assess the long-term implications (morbidity) and efficacy of these arthrodesis techniques in a live setting to get a comprehensive understanding of their overall utility and safety.