title: Osteoarthritic cartilage lesions in the bovine patellar groove: a macroscopic, histological and immunohistological analysis.
abstract: A high percentage of osteoarthritis (OA)-like patellar groove lesions in the stifle joint in calcium-deficient bulls has been recently reported. The prevalence of these lesions in bulls deficient in or supplemented with calcium was compared to findings in culled and healthy bulls to determine whether they represent normal anatomical variations, developmental anomalies or OA. It was hypothesized that the patellar groove lesions may represent OA. Distal cartilage samples from 160 femurs were analysed using a macroscopic Société Française d'Arthroscopie (SFA) OA grading system. Samples representing different SFA grades were subjected to Osteoarthritis Research Society International (OARSI) histological and high-mobility group box 1 (HMGB1) immunohistological OA grading. For a qualitative analysis three OA samples were immunostained for interleukin (IL)-1β, matrix metalloproteinase (MMP)-13 and collagenase-produced COL2-3/4M neoepitopes. Patellar groove lesions were found in 48% of the femurs and were highest in calcium-deficient animals (71%, P<0.001). All three different grading systems disclosed OA in culled bulls, but no focal areas of cartilage necrosis. OARSI and HMGB1 grades were fairly concordant (Spearman's ρ=0.95, P<0.001; Cohen's κ=0.23, P<0.005), both with a slight disparity with the SFA grade (ρ=0.80 and 0.87, P<0.01; κ=0.36 and 0.46, P<0.001). IL-1β, MMP-13 and COL2-3/4M staining patterns were compatible with OA. The study showed that patellar groove lesions are common in bulls. In all SFA, OARSI and HMGB1 graded samples the lesions clearly demonstrated OA and showed OA-typical pathophysiology. Arthroscopic SFA grading showed similar changes in calcium-deficient and calcium-supplemented bulls, but in the absence of a time course study and histological data the primary nature of these lesions could not be established with certainty.
authors.affiliation: Helsinki University, Faculty of Veterinary Medicine, Department of Basic Veterinary Medicine, P.O. Box 66, 00014 Helsinki, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Heinola
authors.affiliation: Helsinki University, Faculty of Veterinary Medicine, Department of Basic Veterinary Medicine, P.O. Box 66, 00014 Helsinki, Finland.
authors.forename: A
authors.initials: A
authors.lastname: Sukura
authors.affiliation: Helsinki University Central Hospital and University of Helsinki, Department of Medicine, Biomedicum 1, P.O. Box 700, Helsinki, Finland.
authors.forename: L M
authors.initials: LM
authors.lastname: Virkki
authors.affiliation: Helsinki University Central Hospital and University of Helsinki, Department of Medicine, Biomedicum 1, P.O. Box 700, Helsinki, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Sillat
authors.affiliation: Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawinskiego 5B, 02-106 Warsaw, Poland.
authors.forename: T
authors.initials: T
authors.lastname: Lekszycki
authors.affiliation: ORTON Orthopaedic Hospital of ORTON Foundation, P.O. Box 29, 00281 Helsinki, Finland; Helsinki University Central Hospital and University of Helsinki, Department of Medicine, Biomedicum 1, P.O. Box 700, Helsinki, Finland; COXA Hospital for Joint Replacement, P.O. Box 652, 33101 Tampere, Finland. Electronic address: yrjo.konttinen@helsinki.fi.
authors.forename: Y T
authors.initials: YT
authors.lastname: Konttinen
mesh_terms: D000818:Animals; D002356:Cartilage / Q000473:pathology*; D002417:Cattle; D002418:Cattle Diseases / Q000473:pathology*; D003094:Collagen / Q000235:genetics / Q000378:metabolism; D053583:Interleukin-1beta / Q000235:genetics / Q000378:metabolism; D008297:Male; D053509:Matrix Metalloproteinase 13 / Q000235:genetics / Q000378:metabolism; D010003:Osteoarthritis / Q000473:pathology / Q000662:veterinary*; D010329:Patella / Q000473:pathology*
chemical_list: D053583:Interleukin-1beta; D003094:Collagen; D053509:Matrix Metalloproteinase 13
keywords: Cartilage; HMGB1 protein; Osteoarthritis