Abstract

Background

Viscosupplementation refers to the use of hyaluronic acid injections into diarthrodial joints, typically the knee, to provide lubrication and shock absorption. It is commonly used for the treatment of knee Osteoarthritis (OA). One product, Synvisc® (Sanofi, Inc., Bridgewater, NJ), has been used in our clinic for over 20 years. Given the increasing prevalence of obesity and its known negative impact on OA outcomes, this study aimed to evaluate the influence of Body Mass Index (BMI) on patient outcomes following Synvisc® injection.

Methods

A single-center retrospective medical record review was conducted on 46 patients who received Synvisc® injections for symptomatic knee OA. Patient-Reported Outcome Measures (PROMs) included the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form, Lysholm Knee Scoring Scale, 12-Item Short Form Survey (SF-12), and the Knee Injury and Osteoarthritis Outcome Score (KOOS), recorded before and after injection. Patients were categorized as non-obese or obese using NIH BMI guidelines. Statistical significance was set at p<0.05.

Results

Significant improvements in PROMs were observed from baseline following Synvisc® injections in most patients. These improvements were more pronounced in non-obese patients (p<0.05). Obese patients showed greater activity and functional limitations, indicating a BMI-related effect on treatment response.

Conclusion

Synvisc® injections improved patient-reported- outcomes/quality of life and pain relief across all patient cohorts. However, pre-obese patients experienced more substantial improvements in pain sensation and quality of life metrics compared to their obese counterparts.

Keywords:Viscosupplementation; Osteoarthritis; Hyaluronic acid; Body mass index; Patient reported outcome measures