After inclusion in the study, all of the patients will be instructed (for the duration of the study) not to use drugs with a direct action on the cartilage (e.g., chondroprotectors, such as glucosamine and chondroitin) to avoid confounding biases regarding the effects of the treatments. No patients will be included who had started using these drugs in the previous 6 months to avoid the initial effect of this treatment being a confounder in terms of clinical improvement.