New Study Provides Support for Chondroitin for Knee Osteoarthritis, Researchers Say It Refutes Prior Meta-Analysis

Researchers for a new study published online in the Annals of the Rheumatic Diseases say that supplemental chondroitin sulfate was found to significantly reduce the cartilage volume loss in patients with knee osteoarthritis in as little as six months into treatment, and reduced bone marrow lesions after 12 months of treatment. The researchers suggest that chondroitin sulfate helps protect joint structure.

The multicenter, randomized, double-blind, placebo-controlled trial was performed on 69 patients with knee osteoarthritis with clinical signs of synovitis (inflammation of the synovial membrane). Its intent was to examine the effects of treatment on cartilage volume loss, subchondral bone marrow lesions, and synovitis in patients with knee osteoarthritis.

Subjects were randomized to receive 800 mg of a “highly purified, pharmaceutical-grade” chondroitin sulfate or placebo, once daily, for six months. After six months, both the intervention and placebo groups were then given the 800-mg chondroitin dose once daily for another six months. Cartilage volume and bone marrow lesions were assessed by quantitative magnetic resonance imaging (qMRI) at baseline, six months, and 12 months. Synovial membrane thickness was assessed at baseline and at six months.

The researchers said that the chondroitin sulfate group showed significantly less cartilage volume loss than the placebo group as early as six months for the global knee, lateral compartment, and tibial plateaus-effects that were still significant at 12 months. The chondroitin sulfate group also showed significantly lower bone marrow lesion scores at 12 months in the lateral compartment and the lateral femoral condyle.

The researchers note that this is the first time qMRI was used to show that disease-modifying effects of chondroitin sulfate.

The researchers say these positive results refute conclusions reached by S. Wandel et al. in a meta-analysis published in the British Medical Journal last year, which stated that “compared with placebo, glucosamine, chondroitin, and their combination do not reduce joint pain or have an impact on narrowing of joint space.”

Jean-Pierre Pelletier, MD, who lead the group of Canadian researchers for the Annals of the Rheumatic Disease study, said, “Chondroitin sulfate is a safe drug with an overall positive effect on osteoarthritis, significantly reducing the volume of cartilage loss in knee osteoarthritis.” He said that this study provided “for the first time new information on its positive effect in vivo on other structural changes observed in this disease.”

He said that the results show that chondroitin sulfate is able to slow the progression of osteoarthritis, although it does not mean it can cure the disease. “The cure involves the regression of all lesions related to osteoarthritis, and that’s not the case. Chondroitin sulfate slows the progression of the disease. This is an important finding, as a decrease in the rate of progression of cartilage loss in knee osteoarthritis patients, as seen by MRI, could potentially reduce the need for total knee replacement-a phenomenon that has been observed in other MRI clinical studies.”

He also noted, “It is important that patients are provided with highly purified pharmaceutical-grade chondroitin sulfate, the one used in this study, as this is the only one that can guarantee such efficacy and…safety results.”