Single Injection of Highly Concentrated Hyaluronic Acid Provides Improvement of Knee Joint Arthrokinematic Motion and Clinical Outcomes in Patients with Osteoarthritis—Non-Randomized Clinical Study

<b>Background/Objectives</b>: Intra-articularly administered hyaluronic acid (HA) products improve the mechanical properties of the synovial fluid (SF) in an osteoarthritic (OA) joint and thus improve joint motion quality. However, current diagnostic methods, used to assess the clinical effectiveness of HA-based therapy are based on subjective tools, and are unable to deliver solid data about the actual impact of this molecule on joint functioning. Consequently, the aim of this study was to objectively assess the effect of HA IA injection on joint motion quality with vibroarthrography (VAG) and the subsequent evaluation of patient clinical status. <b>Methods</b>: A total of 40 patients with knee OA and 50 healthy individuals as the control group were enrolled in this non-randomized clinical and were subjected to therapy consisting of a single IA administration of highly concentrated HA gel (Biolevox™ HA ONE). The therapy assessment included an evaluation of joint motion quality with the VAG method and a subsequent evaluation of the knee joint function using the WOMAC questionnaire for up to 60 days after the therapy. <b>Results</b>: A single IA injection of HA led to an immediate and sustained improvement of the motion quality of OA-affected synovial joints, as proven by the significant reduction in all measured vibroacoustic emissions (VMS, R4, P1, and P2). Furthermore, this was followed by a significant improvement in all WOMAC sub-scales, observed at 30 and 60 days after the therapy. <b>Conclusions</b>: The results of this study demonstrate that an IA-HA injection can improve the motion quality of OA-affected joints. Importantly, the observed improvement in joint motion quality is directly correlated with early recovery of joint function. These findings provide objective evidence that HA effectively enhances OA-affected joint biomechanics, contributing to a better understanding of the actual impact of this prevalent OA therapy on knee joint motion quality.