TITLE:
A Search for Factors that Predict the Efficacy of Viscosupplementation in Knee Osteoarthritis
AUTHORS:
R. Michelle Koolaee, H. Ralph Schumacher, Michael Shoemaker, Sarah Mooar, Sally Pullman-Mooar
KEYWORDS:
Hyaluronic Acid, Viscosupplementation, Osteoarthritis, Knee Osteoarthritis, Efficacy, Hyaluronate
JOURNAL NAME:
Open Access Library Journal,
Vol.1 No.5,
August
14,
2014
ABSTRACT: Objective: Previous research demonstrates inconsistent effects of hyaluronate (HA) viscosupplementation on patients with knee osteoarthritis (OA). The purpose of this study was to evaluate factors that predict clinical response to a single intra-articular injection of Hylan GF-20. Methods: This was an observational study of 55 patients with knee OA, scheduled to receive intra-articular injections of Hylan GF-20. These patients met the institution’s guidelines for use of viscosupplementation, which entails failure/intolerance of medical management of OA. At baseline, patients completed a series of questionnaires, including the Knee Injury and Osteoarthritis Outcome Score (KOOS) and Patient Health Questionnaire (PHQ-9) depression score. Questionnaires were repeated at three months post-injection. A clinical responder was someone with a change in KOOS score which exceeded the mean minimal detectable change (MDC) values calculated based on test-retest reliability coefficients reported in four prior studies. Hypothesized predictors of response included PHQ-9 score, baseline visual analog scale (VAS) pain score, age, body mass index (BMI), and Kellgren score. Results: There were 35 responders and 20 non-responders. There were no statistically significant differences between responders and non-responders for any of the primary predictors. There were no differences for secondary predictors, including history of knee injury or smoking, prior HA injection, prior intra-articular corticosteroid injection, or location of OA. There was a moderate negative correlation between age and change in total KOOS score (r = —0.32, p = 0.01). Conclusions: Our research did not confirm previous predictors of response to hyaluronate injections, and highlighted the need for prospective studies in order to answer this question.