Area of cartilage accessible to curettage for subsequent arthrodesis of the equine proximal interphalangeal joint. Comparison of conventional and collateral ligament sparing approaches.

This study compared the areas of cartilage accessible for curettage in arthrodesis of the equine proximal interphalangeal joint using the conventional and collateral ligament sparing approaches. For this purpose, forelimbs and hindlimbs of six equine cadavers without radiographic evidence of proximal interphalangeal joint disease were used. One limb of each pair of limbs was randomly assigned to a dissection using a standard approach to the proximal interphalangeal joint including transection of the collateral ligaments, while each contralateral limb was exposed using the same approach but leaving the collateral ligaments intact. Hohmann retractors and Spratt curettes were then used to remove as much articular cartilage as possible. Finally, proximal interphalangeal joints were photographed and image analysis was performed. Using the collateral ligament sparing procedure, the mean percentage of articular cartilage surface removed (41.2%) was significantly less than using the conventional procedure (79.6%) (p <0.01). The difference between forelimbs and hindlimbs was not significant.