Characterisation of pain-related behaviours in association with joint pathology in an 8-week antigen-induced arthritis model

Abstract

s / Osteoarthritis and Cartilage 22 (2014) S7–S56 S37 articular antigen leads to additional pain-related behaviours. This approach should enable us to dissect relationships between specific pain pathways and joint pathology. 54 PAIN SIGNALLING IN RODENT JOINTS BY SERINE PROTEASES J.J. McDougall, A. Reid, F.A. Russell. Dalhousie Univ., Halifax, NS, Canada Purpose: Serine proteases modulate pain by either activating or disarming protease-activated receptors (PARs). The aim of the present study was to assess the effect of two serine proteases (cathepsin G and neutrophil elastase) on knee joint mechanosensitivity and pain in rodents. Methods: Electrophysiological recordings from knee joint primary afferents were carried out in deeply anaesthetised male Wistar rats in response to normal and hyper-rotation of the knee. Animals were treated with either normal or denatured cathepsin G (1ng 10mg; close intra-arterial injection) and nerve recordings repeated. In separate experiments, the effect of intra-articular injection of human neutrophil elastase (1-50mg rat; 1-5mg mouse) on pain behaviour in awake and unrestrained Wistar rats and c57bl/6 mice was determined by measurement of hindlimb incapacitance (weight bearing) and von Frey hair tactile allodynia. Results: Peripheral administration of cathepsin G caused a dosedependent reduction in joint mechanosensitivity compared to boiled enzyme, which had no discernible effect (P 0.8). As expected, KOOS is more strongly correlated with physical subscales of the SF-36 across different conditions, interventions and languages. While KOOS demonstrates large effect sizes post-surgery, future studies should prioritise evaluation of longitudinal validity to adhere with updated recommendations for evaluation of measurement properties. 56 ALL-CAUSE MORTALITY AND SERIOUS CARDIOVASCULAR EVENTS IN PEOPLE WITH HIP AND KNEE OSTEOARTHRITIS: A POPULATION BASED COHORT STUDY G.A. Hawker yz, R. Croxford x, A.S. Bierman y, P.J. Harvey yz, B. Ravi y, I. Stanaitis z, L.L. Lipscombe yz. yUniv. of Toronto, Toronto, ON, Canada; zWomen’s Coll. Hosp., Toronto, ON, Canada; x Inst. for Clinical Evaluative Sci. (ICES), Toronto, ON, Canada Purpose: Osteoarthritis (OA) is under-treated in part due to the high coprevalence of other chronic conditions. Approximately 90% of people aged 65þ years with symptomatic OA have at least one additional chronic condition; OA and cardiovascular disease, CVD, are among the most common dyads seen in clinical practice. CVD, in particular, may be perceived as precluding the use of OA therapies (e.g. NSAIDs). Inadequately treated, people with OA may manage their OA by avoiding activities, like walking, that exacerbate symptoms. Reduced physical activity may further increase these individuals’ CVD risk. We therefore examined the contribution of OA disability to other CVD risk factors, including prior history of a CVD event, on risk for CVD events. Methods: This retrospective cohort study used data from a population cohortwith symptomatic hip and kneeOA that was recruited from 199698 through a screening survey of 100% of the population aged 55þ years in twoOntario regions (n1⁄42225hadOAconfirmedonexamination andxray). The baseline survey assessed: socio-demographics; smoking; selfreportedheight,weight andNSAIDuse; comorbidity (includingphysician diagnosis and treatment in thepast year forhighbloodpressure, diabetes, andheartproblems); andmentalhealth status.OAdisabilitywas assessed using theWOMAC function subscale, useof awalkingaid (yes/no) and the Health Assessment Questionnaire walking disability subscale (0–3; higher scores indicate greater disability). The current study used baseline surveys linked to provincial health administrative databases.