Lokalisationen av osteochondrosförändringar hos svenska halvblodshästar

Abstract: The aetiology of osteochondrosis (OC) is known to be complex and multifactorial. The occurrence of bone fragments in joints and their connection to osteochondral disease are no exception. In the hock and stifle joint of the horse this type of lesion has generally been considered to be of osteochondral origin, while the process behind these fragments in the fetlock joint has been up for discussion. The objective of this study was to determine the frequency and the localisation of OC in Swedish warmblooded horses. In order to do so all radiographs of stifle, hock and fetlock joints performed on Swedish warmblooded horses during the period of 1992-1999 at Regiondjursjukhuset in Helsingborg were examined and the material was divided into two groups. The first group contained all horses that had been examined without any prior suspicion of lameness as part of a prepurchase examination, for export or for breeding programs. The second group were radiographed as part of a veterinary clinical investigation. The result was transfered into two files named inspection file and clinical file. The results show that horses in the clinical file had a prevalence of OC in the stifle joint that were 4 times as high as those in the inspection file. In the inspection file the majority of OC were found in the hock joint. Compared to prior studies of OC in horses this study showed a lower prevalence of OC. In the inspection file 6,0 % of the horses were diagnosed with OC in the hock joint and 3,0 % with OC in the stifle joint. In the clinical file the prevalence of OC was found to be 6,3% for the hock joint and 11% for the stifle joint. The calculation regarding fragments in the fetlock joint resulted in 24% prevalence among horses in the clinical file and 17% prevalence among horses in the inspection file. In the stifle joint the most common specified position of OC was the lateral trochlea of femur while the most common position in the hock joint was the intermediate ridge of tibia. In the fetlock the majority of the fragments were located at the palmar/plantar aspect and in the hind legs. Dorsal fragments were almost equally common here, but with a slight higher frequency in the front legs. Gender comparison could only be studied in the clinical file but without any valid conclusions.