[Effectiveness of sodium hyaluronate in patients with gonarthrosis: randomized comparative study]

Hyaluronic acid is a major component of synovial fluid and cartilage; it plays an essential role in joint function. This concept is based on the hypothesis that intraarticular sodium hyaluronate injections improve articular function upon restoring synovial fluid viscosupplementation and promoting endogenous synthesis.

Forty randomly selected patients older than 50 years of age, with a diagnosis of gonarthrosis, standard treatment-naïve, were divided into two 20-patient groups. The first group was treated with five 2.5 ml doses of hyaluronic acid, at one dose per week. The second group was treated with a single 2 ml dose of intraarticular methylprednisolone. A survey containing the Womac functional scale and the pain visual analogue scale was applied to both groups before and 3 months after treatment.

A statistically significant reduction in pain (visual analogue scale) was observed 3 months after treatment in group H (1.6 +/- 0.88) and group M (2.95 +/- 1.84), as well as a functional post-treatment improvement in the Womac scale. Results for post-treatment pain were 5.43 +/- 1.05 for group H and 7.86 +/- 0.77 for group M; results for post-treatment stiffness were 3.05 +/- 0.82 for group H and 3.7 +/- 0.85 for group M; and finally for post-treatment functional capacity the results were 12.25 +/- 0.82 for group H and 18.95 +/- 0.85 for group M.

Intraarticular sodium hyaluronate is more effective for pain and function than methylprednisolone. However, it involves higher costs than conservative treatment and fewer costs than surgical treatment, as well as the discomfort resulting from repeated intraarticular injections and the possibility of anaphylactic reaction.