A Retrospective Study of the Mechanism, Diagnoses,Treatments and Prognoses of Osteochondritis Dissecans and an Analysis of the Different Treatments' Effectiveness in the Horse.

Abstract

Osteochondritis dissecans (OCD) is a joint disease in which the cartilage and/or bone dissociates from the articular bone, causing chondronecrosis and lameness. As such, OCD is a major issue in the equine sports industry and general equine industry. OCD can develop in virtually any joint, presenting bilaterally or unilaterally in multiple or single joints. The mechanisms that cause OCD are hypothesized to include developmental issues (anatomic and genetic) and possible positive correlations with over-training. This review was performed via gathering data from previous studies to inform the reader about OCD in horses including the various methods of identifying and treating OCD. The diagnostic methods discussed include the lameness exam, radiography, ultrasonography and arthroscopy. Regarding treatments, a primary goal of this is to ascertain whether surgical or regenerative treatments are more successful. The treatments discussed include conservative management (rest), arthroscopic debridement, polydioxanone (PDS) pinning and tissue grafts. To discern between the success of the surgical and regenerative treatments, several criteria were discussed including the success rates of the treatments taking into account their population size, average age of the population, time for recovery, risk of fibrous cartilage replacement, limitations based on the lesion severity within the joint and treatment costs. While rest was successful in returning 33 + 12% of horses to soundness, it was less effective than surgical and regenerative treatments, which were 73 + 3% and 87 + 4% effective, respectively. The results of regenerative treatments for OCD appear to be superior to those of the surgical debridement. Further research topics that would be beneficial include the further development of regenerative treatments and identifying which gene products support hyaline cartilage repair instead of fibrous cartilage replacement.