2014 Volume No 27  pages 213-236
|  Title: Osteochondral lesions in distal tarsal joints of Icelandic horses reveal strong associations between hyaline and calcified cartilage abnormalities | 
| Author: CJ Ley, S Ekman, K Hansson, S Björnsdóttir, A Boyde | 
|  Address: Department of Clinical Sciences, Swedish University of Agricultural Sciences, Box 7054, SE-750 07 Uppsala, Sweden | 
|  E-mail: charles.ley at slu.se | 
|  Key Words: Articular cartilage, subchondral bone, osteoarthritis, equine tarsus, backscattered electron microscopy, iodine-staining, confocal scanning light microscopy, microcomputed tomography. | 
| Publication date: March 25th 2014 | 
|  Abstract: Osteochondral  lesions in the joints of the distal tarsal region of young Icelandic horses provide  a natural model for the early stages of osteoarthritis (OA) in low-motion  joints. We describe and characterise mineralised and non-mineralised osteochondral  lesions in left distal tarsal region joint specimens from twenty-two 30 ±1  month-old Icelandic horses. Combinations of confocal scanning light microscopy,  backscattered electron scanning electron microscopy (including, importantly,  iodine staining) and three-dimensional microcomputed tomography were used on specimens  obtained with guidance from clinical imaging. Lesion-types were described and  classified into groups according to morphological features. Their locations in  the hyaline articular cartilage (HAC), articular calcified cartilage (ACC), subchondral  bone (SCB) and the joint margin tissues were identified and their frequency in  the joints recorded. Associations and correlations between lesion-types were  investigated for centrodistal joints only. In centrodistal joints the  lesion-types HAC chondrocyte loss, HAC fibrillation, HAC central chondrocyte  clusters, ACC arrest and ACC advance had significant associations and strong  correlations. These lesion-types had moderate to high frequency in centrodistal  joints but low frequencies in tarsometatarsal and talocalcaneal-centroquartal  joints. Joint margin lesion-types had no significant associations with other  lesion-types in the centrodistal joints but high frequency in both the  centrodistal and tarsometatarsal joints. The frequency of SCB lesion-types in  all joints was low. Hypermineralised infill phase lesion-types were detected. Our  results emphasise close associations between HAC and ACC lesions in equine  centrodistal joints and the importance of ACC lesions in the development of OA  in low-motion compression-loaded equine joints.                    | 
| Article download: Pages 
                213-236 (PDF file) | 

 
     
     
     
    