Background Application of intraarticular injections of hyaluronic acid (hyaluronate sodium) and betamethasone (a two-component glucocorticoid with rapid and delayed action) is one of the widely accepted treatments of primary osteoarthritis (POA).
Objectives To compare the efficacy of the treatment of POA of the knee with intraarticular hyaluronate injections to the treatment with intraarticular betamethasone injections.
Methods This open, prospective study involved two groups with 45 patients with POA of the knee matched by demographics (age, sex, BMI) and clinical characteristics (disease duration, bilateral or unilateral gonarthrosis in II and III stage according to Kellgren Lawrence scale). Patients in the first group received 3 intraarticular injections of sodium hyaluronate once a week (injection of hyaluronic acid of high concentration (30mg/2ml) and large molecular weight (1.9 million Daltons)), total of 90 mg in one knee, at the beginning of the 6-month follow-up period. Patients in the second group received 2 injections of betamethasone (7 mg/ml) with a period of 3 weeks between injections. To evaluate the effectiveness of treatment we observed severity of knee pain on visual analogue scale VAS 0-100mm, functional status of the patient through patient’s assessment of the ability to walk (VAS 0-100mm), and clinical findings of limitation of motion in the knee expressed through Lickert scale (0-3) after 3 and 6 months after last received injection. For statistical analysis of the obtained values Fischer test and Student t test were used.
Results . In the group of patients who received hyaluronate, pain intensity was significantly lower one month after receiving the last injection compared to baseline (VAS 82 vs.49, p <0.001). This effect was most pronounced after 3 months (VAS 27, p <0.001), and was held after 6 months, somewhat less pronounced (VAS 36, p <0.001). Among the patients who received betamethasone, the pain intensity was lower one month after the last injection than the initial value, but not statistically significant (VAS 75 vs.60, p>0.05); deteriorating result was obtained after 3 (VAS 65) and 6 months (VAS 70). Pain intensity was significantly lower in the first than in the second group after 3 (VAS 27 vs. 65, p<0.001) and after 6 months (VAS 36 vs. 70, p<0.001). Functional ability in the first group was significantly higher after 3 (VAS 42 vs. 70, p<0.001) and 6 months (VAS 73, p<0.001), while in the second group it is slightly higher after 3 months, but with no statistical significance (VAS 46 vs. 52, p>0.05). Functional ability was significantly higher in the first group then in the second after 3 (VAS 70 vs.52, p<0.001) and 6 months (VAS 73 vs.47, p<0.001). The limitation of motion in the knee joint in the first group was significantly lower 3 months after the initial value (2.1 vs. 1.7, p <0.005), no statistically significant differences were observed between the groups after 3 (1.7 vs.1.8, p>0.05) and 6 months (1.8 vs.2.0, p>0.05) of the treatment.
Conclusions Intraarticular application of hyaluronic acid of high concentration and high molecular weight showed significantly greater efficacy in terms of pain intensity and functional ability in the treatment of knee osteoarthritis compared with intraarticular application of betamethasone therapy.
Disclosure of Interest None Declared