012 RISK FOR SYMPTOMATIC KNEE OSTEOARTHRITIS DOES NOT VARY BY KNEE EXTENSOR STRENGTH AND KNEE JOINT POSITION SENSE

Abstract

011 – Figure 1 012 RISK FOR SYMPTOMATIC KNEE OSTEOARTHRITIS DOES NOT VARY BY KNEE EXTENSOR STRENGTH AND KNEE JOINT POSITION SENSE N.A. Segal1, N.A. Glass1, D. Felson2, M. Hurley3, M. Yang2, M. Nevitt4, C.E. Lewis5, J.C. Torner1 1Univ. of Iowa, Iowa City, IA; 2Boston Univ., Boston, MA; 3King’s Coll. London, London, United Kingdom; 4Univ. of California at San Francisco, San Francisco, CA; 5Univ. of Alabama at Birmingham, Birmingham, AL Purpose: Quadriceps weakness and impaired knee joint position sense (proprioception) have been linked cross-sectionally with knee OA. While neither of these factors has been independently associated with new onset disease, it is possible that one substitutes for the other and that only when both are impaired is the joint at risk. This study investigated whether sensoriomotor dysfunction the combination of quadriceps weakness and impaired knee joint position sense precedes development of symptomatic knee OA. Methods: The Multicenter Knee Osteoarthritis (MOST) Study is a longitudinal, observational study of adults age 50-79 years with knee OA or at high risk for knee OA. MOST subjects were excluded if they had symptomatic knee OA at baseline. Those with missing data or knee pain that interfered with strength testing were also excluded. Subjects underwent bilateral, weight bearing, fixedflexion radiographs, right knee joint reposition tests, and isokinetic knee extensor strength assessments; completed the Physical Activity Scale for the Elderly (PASE) and WOMAC questionnaires; and had height, and weight measurements taken. Symptomatic knee OA was defined as the combination of knee OA (KL grade ≥2) and frequent knee pain or stiffness at follow-up. The relationship between combinations of the tertiles of sex-specific baseline peak KES and tertiles of JPS and development of incident symptomatic knee OA at 30-month follow-up was evaluated with logistic regression adjusted for age, BMI, knee injury, knee surgery, and PASE score. Secondary analyses defined joint position sense as (1) the subject-specific variance over the 10 trials and (2) the average joint position sense over the 10 trials, and also assessed the interaction of knee extensor strength and joint position sense in predicting the outcome using generalized linear models. Results: 1565 subjects (911 women and 654 men) met eligibility criteria and were included in this study. The mean±SD age was 62.1±8.0 years, BMI was 29.8±5.4kg/m2, PASE score was 182.9±88.7, and WOMAC pain subscale was 2.2±2.8. There S16 Oral Presentations was no association between the combinations of knee extensor strength and joint position sense and incident symptomatic knee OA at 30-month follow-up. Secondary analyses, also did not demonstrate a statistically significant relationship between the interaction of knee extensor strength and either the average joint position sense or the variance in joint position sense and the development of incident symptomatic knee OA (all p>.25). Relationship Between Tertiles of Strength-Proprioception and Incident Symp-