Efficacy of ultrasound guided injections of a cross-linked sodium hyaluronate combined with triamcinolone hexacetonide for osteoarthritis of the knee

Porta, F.; Filippou, G.; Sakellariou, G.

Background: According to guidelines, the use of steroid and/or hyaluronate (HA) intra-articular injections for knee osteoarthritis (KOA) is controversial. Heterogeneity of studies and difference in HAs characteristics does not allow to draw safe conclusions. One of the major concerns is the accuracy of the procedure as up to 1/3 of injections could miss joint space when performed blindly (1), negatively affecting the efficacy of HA that needs to be placed correctly in the joint space Objectives: The aim of our study was to evaluate the longterm efficacy of a novel association of a Cross-Linked Sodium Hyaluronate Combined With Triamcinolone Hexacetonide (SHCTH) in patients with KOA in a real life setting. Methods: We retrospectively evaluated the clinical and ultrasonographic (US) data of patients (pts) affected by symptomatic KOA with intra-articular injections of SHCTH (1 injection every 6 months). Pts with concomitant inflammatory arthropaties were excluded. US guidance was carried out with the in plane technique choosing either the lateral suprapatellar or midpatellar approach. All pts were evaluated for pain with a VAS 0-10 for pain at baseline and after 2 weeks, 1, 3, 6, 9 and 12 months, with the WOMAC questionnaire and with US, scoring joint effusion, synovial hypertrophy (SH) and power Doppler (PD) synovial signal. Due to the retrospective design, the WOMAC data were available as VAS or Likert scales;to allow comparability these values were standardized. Clinical and US variables at different time points were compared using the Wilcoxon rank sing test, the McNemar test or the paired samples t-test, depending on the variable. Results: 49 knees (43 pts, median age 70.6 years, 24 women) were included in the study. Kellgren Lawrence grade was 1 for 5 knees, 2 for 10, 3 for 17 and 4 for 9. SHCTH was delivered correctly in the joint space in all patients as assessed by US check during the injection and no side effects occurred. Of the 49 knees, 28 had an available 6 months follow-up, while 21 completed the 12 months follow-up, with an attrition mostly related to the COVID 19 pandemic. A rapid and sustained statistically significant decrease of both VAS pain and the WOMAC subscales was observed. The reduction of pain was already significant at 2 weeks, probably thanks to the corticosteroid component. At US evaluation, effusion significantly decreased at all time points. Although SH scores also significantly decreased, the effect on the proportion of affected joints was not as relevant. The reduction of PD was significant until month 9. Detailed results are presented in Table 1. Conclusion: Our data show that US guided SHCTH injections provide a rapid and sustained clinical response in patients with symptomatic OA. Besides the effect on pain, the US data confirm the effect of the drug on the inflammation. US guidance guaranteed the correct placement of the product in all patients and eliminated the bias of wrong placement that may occur with blind injections, thus allowing to draw safe conclusions on the efficacy of SHCTH for the treatment of KOA.