Have you tried a Bionicare unit yet? Don't know if it is available in Europe yet, but it just got it's FDA and Medicare approvals in the US. It started as an attempt to stimulate bone, but research found that changing waveforms could stimulate hyaline cartilage. The unit uses a low-level electric field to generate a negative charge in the knee joint, identical to the charge present in a healthy knee. Cartilage is aneural and avascular, so the chondrocytes rely on a neg charge to trigger regeneration. The cartilage doesn't know or care where the field comes from. Bottom line is that the unit has impeccable science behind it from Johns-Hopkins and is being prescribed by many of the top knee doctors in the US. The clinical results are impressive in restoring function and reducing pain. It takes a motivated patient becuase therapy is 6-8 hrs / day for several months. It took years to create the problem, it takes months to restore it. This is not for the patient who is waiting for a cure in a pill or a magic wand.