Epsilon Archive for Student Projects

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.

Förekomst av fragment i hästens leder har länge varit ett omdiskuterat ämne. I hasled och knäled anses lesionerna vara av osteochondralt ursprung medan det råder oenighet angående fragment som uppstår i kotleden. Etiologin bakom uppkomsten av osteochondros är komplex och flertalet faktorer påverkar processen.
I studien har alla Svenska halvblod som röntgat has, knä eller kotled under åren 1992-1999 vid Regiondjursjukhuset i Helsingborg undersökts. Materialet delades upp i två grupper där den ena bestod av 1035 hästar som genomgått en besiktnings- eller "exportröntgen" undersökning eller röntgats i ett avelsprogram och den andra av 3800 hästar som röntgats som en del i en klinisk utredning. Syftet med studien var att undersöka lokalisationen av osteochondros (OC) hos Svenska halvblodshästar.
Resultaten visade att hästarna i klinikfilen hade nästan 4 gånger så hög frekvens av OC i knäleden som hästarna i besiktningsfilen. Prevalensen OC i hasleden var lika i de båda filerna. I klinikfilen hittades dubbelt så mycket OC i knäleden jämfört med hasleden medan besiktningsfilen hade mer OC i hasleden i relation till andelen i knäleden. Jämfört med liknande forskning var andelen OC i denna studie låg. Besiktningsfilen hade 6,0% OC i hasleden och 3,0% i knäleden medan klinikfilen hade 6,3% i hasleden och 11% i knäleden. Alla typer av fragment i kotlederna utvärderades. I besiktningsfilen var prevalensen 24% och i klinikfilen 17%. I knäleden var den vanligaste lokalisationen femurs laterala rullkam medan främsta predilektionstället i hasleden var tibias sagittala kam. I kotleden var de flesta fragmenten palmara/plantala och majoriteten satt i bakkotorna. Dorsala fragment förekom i nästan lika hög utsträckning men dessa var i högre grad lokaliserade till frambenen. Andelen OC i förhållande till kön kunde endast studeras i klinikfilen men inga säkra slutsatser kunde dras från detta material.