Longterm effects of intraarticular hyaluronan on synovial fluid in osteoarthritis of the knee

J Rheumatol. 2006 May;33(5):946-50.

Abstract

Objective: Intraarticular (IA) hylan injections constitute second-line therapy for osteoarthritis (OA) of the knee, but human studies suggesting a possible mechanism of action are lacking. We examined the effect of IA Hylan GF-20 injections on synovial fluid (SF) hyaluronan (HA) concentration, viscosity, and elasticity over a 6-month period in patients with mild to moderate OA of the knees.

Methods: Patients with symptomatic knee OA (Osteoarthritis Research Society International grade 1-2) had SF aspirated from the study knee pre- and 3 and 6 months post-Hylan injection. Primary endpoints included SF HA concentration, viscosity, and elasticity. SF HA concentration was determined using uronic acid assay, and rheology measured using a micro-Fourier rheometer.

Results: Sequential SF samples were available from 32 of 60 subjects injected at baseline (15 men, 17 women; mean age 65 yrs) at 3 months post-injection. The mean HA concentration had increased by 13% (p<0.0008), and the complex shear modulus had increased by 16% (p<0.03). Sufficient SF was also available from 19 of these subjects at 6 months post-injection when mean HA concentration was 2.24+/-0.62 mg/ml compared to their baseline mean of 2.02+/-0.52 mg/ml, an increase of 10% (p<0.053).

Conclusion: This open-label study showed a statistically significant change from baseline in both SF HA concentration and complex shear modulus at 3 months following IA Hylan GF-20 injection among subjects with mild to moderate knee OA. These results suggest that one possible mechanism of action of viscosupplementation is to promote endogenous HA production. Longer-term studies are required to identify whether these changes in SF measures are important for modification of disease progression in knee OA.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Disease Progression
  • Elasticity / drug effects
  • Female
  • Humans
  • Hyaluronic Acid / administration & dosage
  • Hyaluronic Acid / analysis
  • Hyaluronic Acid / therapeutic use*
  • Injections, Intra-Articular
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Osteoarthritis, Knee / drug therapy*
  • Osteoarthritis, Knee / pathology
  • Osteoarthritis, Knee / physiopathology
  • Synovial Fluid / chemistry
  • Synovial Fluid / drug effects*
  • Synovial Fluid / physiology
  • Uronic Acids / analysis

Substances

  • Uronic Acids
  • Hyaluronic Acid