The Comparison of Latero-Medial versus Dorso-Palmar/Plantar Drilling for Cartilage Removal in the Proximal Interphalangeal Joint

SIMPLE SUMMARY: Arthrodesis of the proximal interphalangeal joint consists of the assisted fusion of the proximal and middle phalanges. The main indications for performing arthrodesis in equine patients are chronic osteoarthritis unresponsive to medical treatment, articular fractures, luxation and subluxation. This procedure can allow a return to athletic career in selected cases, or free the animal from chronic pain in others. Arthrodesis is performed through two basic steps: articular cartilage removal and bone immobilization. Whereas several methods have been studied to achieve the second one, little has been investigated for cartilage removal. The most utilized technique consists of disarticulating the joint to remove the cartilage. Other techniques have been investigated to remove enough cartilage to allow bone fusion and reduce the invasiveness of the procedure. The aims of this work were to assess the capability of a lateral drilling approach to the joint to remove a sufficient amount of cartilage, and compare it to the previously proposed dorsal drilling approach. The lateral drilling approach, especially when performed under digital fluoroscopy, turned out to be more efficient in articular cartilage removal in the proximal interphalangeal joint. ABSTRACT: The aims of the present study were to compare the percentages of articular cartilage removed using a lateral drilling approach of the proximal interphalangeal joint (PIPJ) and a dorsal drilling approach, and to assess the usefulness of digital fluoroscopy when performing a lateral drilling approach. Sixty cadaveric PIPJs were drilled using a surgical drill bit to remove the articular cartilage. The limbs were divided into three groups containing 10 forelimbs and 10 hindlimbs each. One group received the dorsal drilling approach, the second one received the lateral drilling approach and the last one received the lateral drilling approach under digital fluoroscopy guidance. The percentage of articular cartilage removed from each articular surface was assessed using Adobe Photoshop (®) software. The percentages of removed cartilage turned out to be significantly higher with lateral approach, especially under fluoroscopic guidance, both in the forelimbs (p = 0.00712) and hindlimbs (p = 0.00962). In conclusion, the lateral drilling approach seems to be a minimally invasive technique with which to perform PIPJ arthrodesis, even more efficient than the previously reported dorsal approach.