Efficacy of intra-articular hyaluronic acid injections and exercise-based rehabilitation programme, administered as isolated or integrated therapeutic regimens for the treatment of knee osteoarthritis

Purpose: To assess the efficacy of intra-articular hyaluronic acid (HA) injections and exercise-based rehabilitation (EBR) programme, administered as isolated or integrated for the treatment of knee osteoarthritis.
Methods: One hundred sixty-five patients affected by moderate degrees of knee OA were randomly divided into three groups. Group 1 (HA) underwent three HA injections (one every 2 weeks); group 2 (EBR) underwent 20 treatment sessions in a month of an individualized programme; and group 3 (HA + EBR) received both treatments simultaneously. Primary outcome was the Italian version of the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index; secondary outcome was the evaluation of active range of movement (AROM). All patients were evaluated before and 1, 3 and 6 months after treatment. Significance was set at p < 0.05.
Results: Two patients in each group were lost to follow-up. No adverse events occurred. All groups experienced improvements at 1-month follow-up. No further improvements could be detected within groups over time. At 1-month follow-up, WOMAC pain subscale showed significant improvement in group 3 compared to group 1 (p = 0.043). WOMAC pain, stiffness and function subscales showed that group 2 significantly worsened between 1 and 6 months after treatment (p = 0.004, p = 0.026 and p = 0.025, respectively). AROM revealed no significant differences between and within groups over time.
Conclusions: Intra-articular HA injections and individualized rehabilitation programmes administered in isolation or in combination are effective in improving knee function and pain relief. The combined treatment showed the greatest pain relief at 1-month follow-up compared to either in isolation. Compared to the previous studies, this is the first study, which proposed an EBR programme tailored to the compartment of the knee joint most involved in the degenerative process.
Level of evidence: I.