In the early stages, pain occurs when squatting or negotiating stairs. As the disease progresses, even walking and prolonged standing can be painful. Disuse leads to muscle wasting, and a sensation of “giving way”.
While cartilage degeneration is the primary pathology, it is not the pain generator, as cartilage lacks pain receptors. The pain comes from abnormalities in the surrounding supportive tissues like bone swelling, meniscal tears, ligamentous strain, tendinopathies and even hypersensitive nerves.
The goal of treatment is primarily to relieve pain, and thereby to eventually restore mobility.
For most patients symptomatic enough to see a doctor for their pain, nutraceuticals like glucosamine and chondroitin are likely to have been tried and found wanting. Synthetic Hyaluronic Acid (viscosupplementation), which when injected into the mild-to-moderately degenerative joint, acts as a shock-absorbing lubricant to relieve pain for up to a year.
Ultrasound guidance is advisable to ensure accurate delivery into the joint space of “dry” joints. Corticosteroids may be used for the occasional inflamed joints. Injection of Platelet-Rich Plasma (PRP) appears to be as good as, if not somewhat better, than viscosupplementation, but comes at a higher cost.
For moderate-to-advanced osteoarthritis that fails to respond adequately to the above, assessing and addressing the pain generators with prolotherapy, PRP or nerve blocks can provide relief for prolonged periods, facilitating physical therapy and muscular rehabilitation.
For advanced disease (“bone-on-bone”), joint replacement (total or partial) is the only realistic option. Treatments to replace cartilage defects with cartilage transplants, cultured chondrocytes or mesenchymal stem cells are currently viable only for small defects, and are very costly.
Promising medications and biologics targeting cartilage regeneration are in various stages of clinical development.