Glucosamine sulfate effect on the degenerated patellar cartilage: preliminary findings by pharmacokinetic magnetic resonance modeling

Normal and degenerated cartilages have different magnetic resonance (MR) capillary permeability (K^trans) and interstitial interchangeable volume (v_e). Our hypothesis was that glucosamine sulfate treatment modifies these neovascularity abnormalities in osteoarthritis. Sixteen patients with patella degeneration, randomly distributed into glucosamine or control groups, underwent two 1.5-Tesla dynamic contrast-enhanced MR imaging studies (treatment initiation and after 6 months). The pain visual analog scale (VAS) and American Knee Society (AKS) score were used. A two-compartment pharmacokinetic model was used. Percentages of variations (postreatment-pretreatment/pretreatment) were compared (t-test for independent data). In the glucosamine group, pain and functional outcomes statistically improved (VAS: 7.3 ± 1.1 to 3.6 ± 1.3, p < 0.001; AKS: 18.6 ± 6.9 to 42.9 ± 2.7, p < 0.01). Glucosamine significantly increased K^trans at 6 months (−54.4 ± 21.2% vs 126.7 ± 56.9%, p < 0.001, control vs glucosamine). In conclusion, glucosamine sulfate decreases pain while improving functional outcome in patients with cartilage degeneration. Glucosamine sulfate increases K^trans, allowing its proposal as a surrogate imaging biomarker after 6 months of treatment.