AB0969 Factors influencing the result of local injection therapy with hyaluronic acid preparations in osteoarthritis of the knee joint

Abstract

BackgroundLocal injection therapy (LIT) with hyaluronic acid (HA) preparations is one of the methods of conservative treatment of the knee joint osteoarthritis (KOA). However, the factors affecting the effectiveness of such treatment require clarification.Objectivesto study the influence of age, body mass index (BMI), stage of KOA, the presence of deformity of the knee joint and enthesitis on the results of LIT with HA preparations in KOA.Methodsfrom September 2017 to June 2019, intra-articular injections of HA were performed in 160 patients with primary and posttraumatic KOA stage I-III. For the analysis, the patients were divided into groups depending on the factor studied: by age into young - 36 (22.5%), middle age - 51 (31.3%), elderly - 61 (38.7%) and old age - 12 (7.5%); by BMI: on patients with normal values - 32 (20%), preobesity - 56 (35%), I - 43 (26.9%), II - 16 (10%) and III - 13 (8.1%) degrees of obesity; by stages of KOA: I - 37 (23.1%), II - 91 (56.8%), III - 32 (20.1%); by the presence of deformity: varus deformity <10° - 83 (51.8%), >10° - 23 (14.4%), valgus deformity - 22 (13.8%), no deformity - 32 (20%); and also depending on the presence (44 (27.5%)) or absence (116 (72.5%)) of enthesites. To assess the results, the pain intensity was determined using a visual analogue scale and the knee injury and osteoarthritis outcome score before treatment, 1, 3, and 6 months after the course of LIT.Results1 month after the course of LIT, the best results were obtained in young patients (p=0.001), as well as stage I of KOA (p=0.0001) and normal BMI values (p=0.034), the worst in elderly patients (p=0.006), at stage III of KOA (p=0.01), varus deformity >10° (p=0.006), obesity degree 3 (p=0.015) and the presence of concomitant enthesitis (p=0.003). 3 months after the course of LIT, the previously identified differences persisted, so the best results were again revealed in young people (p=0.0001), in stage I of KOA (p=0.0001), in the absence of deformity (p=0.002) and in normal BMI values (p=0.002), while lack of improvement or deterioration in elderly patients (p=0.001), in stage III KOA (p=0.0001), varus deformity >10° (p=0.001), obesity degree 3 (p=0.022) and the presence of concomitant enthesitis (p=0.001). 6 months after the course of LIT, the improvement remained as before in young patients (p=0.0001), as well as stage I of KOA (p=0.0001), in the absence of deformity (p=0.001) and with normal BMI values (p=0.0001). Lack of improvement or deterioration of knee joint function 6 months after the course of LIT was found in the elderly (p=0.03) and old age patients (p=0.06), in stage II (p=0.045) and III of KOA (p=0.007), varus deformity >10° (p=0.015), obesity degree 2 (p=0.025) and the presence of concomitant enthesitis (p=0.02).ConclusionThe best LIT results with HA preparations can be obtained in young patients with normal BMI values, at the initial stage of KOA, in the absence of deformity and enthesitis. The elderly age of patients, the presence of stage III KOA, varus deformity of the knee joint >10°, BMI >40 kg/m2, and the presence of enthesitis are associated with the lack of effect from intra-articular injections of HA preparations. Performing LIT with HA preparations in patients with stage II KOA and degree 2 obesity allows maintaining improvement for up to 6 months.Disclosure of InterestsNone declared