Objective: To investigate the effects of intraarticular hyaluronic acid (HA) (Artzal, Seikagaku Corp., Japan) in geriatric participants with unilateral knee osteoarthritis (OA).
Method: This was a prospective, observer-blind study with 6 months follow-up done in the setting of an outpatient rehabilitation department in a university-affiliated tertiary care medical center. Sixty-eight patients, aged 65 years or above, with symptoms and radiographic evidence of unilateral knee OA for at least 6 months were recruited. Patients received five weekly intraarticular injections of Artzal into symptomatic knees. Fifty-six participants completed the study. Fifty age-, body mass- and gender-matched healthy individuals were selected as control. Visual analog scale (VAS), Lequesne index and four balance tests including single-leg stance test (SLS), function reach test (FRT), timed "Up-and-Go" test (TUG) and Berg balance scale (BBS) were assessed before injection and at each follow-up visit in the OA group. Four balance tests were obtained on healthy participants for data comparison.
Results: Before Artzal injections, the OA group showed significantly worse VAS, Lequesne index and four balance tests scores than did the control group (P < 0.001). Significant improvement in all outcome measures were noted at 1 week, 1, 3 and 6 months post the fifth injection compared with baseline before injection. Local adverse events were reported in four patients (7.1%).
Conclusion: Significant improvement in pain, physical function and balance tests was demonstrated after five weekly Artzal injections in geriatric patients with knee OA. The effect had rapid onset at 1 week and may last for 6 months.