Effect of 12 months treatment with chondroitin sulfate on cartilage volume in knee osteoarthritis patients: a randomized, double-blind, placebo-controlled pilot study using MRI
Clinical Rheumatology, 06/26/2012
Clinical Article
Railhac JJ et al. – This pilot study confirms the usefulness of quantitative and qualitative MRI as a sensitive tool to assess a structure modifying drugs in knee osteoarthritis.
Methods- Multicenter, double–blind, placebo–controlled, parallel–group study.
- Symptomatic knee osteoarthritis patients aged 50–75 years received either Structum (500 mg twice daily; N = 22) or placebo (N = 21) during 48 weeks.
- Inclusion criteria were global pain in the target knee ≥30 mm (VAS 0–100) and radiological Kellgren–Lawrence grade 2 or 3.
- Clinical assessments included Lequesne index and VAS for pain on motion, at baseline, 24 and 48 weeks, and MRI at baseline and at 24 and 48 weeks.
- Global and compartments cartilage volume, joint cartilage abnormalities, meniscal lesions, ligaments abnormalities, synovitis, synovial effusion, osteophytes, subchondral cysts, popliteal cysts and subchondral oedema were quantified.
- The quantitative and qualitative reproducibility of MRI was tested by the Spearman correlation coefficient and kappa coefficients, respectively.
- Treatments were compared by an analysis of covariance with baseline value as covariate.
- Groups were comparable at baseline for demographics, disease characteristics, and cartilage volumes.
- A significant inter–readers correlation was seen for the assessment of cartilage volumes, number of cysts, and osteophytes (correlation coefficients from 0.951 to 0.980 within investigator and from 0.714 to 0.957).
- After 48 weeks, symptoms improved in both groups.
- The total cartilage volume increased in the Structum group (+180 mm3 + SD) which opposed to a loss in the placebo (–46 mm3 + SD; NS).
- No statistically significant differences between groups were observed for the other MRI parameters.
- No correlations were evidenced between key MRI parameters changes and symptoms.
- The difference in the evolution of cartilage volume between the two groups could reflect a structure modifying effect of Structum.
