Osteoarthritis (OA) is a joint disorder that affects middle aged and older adults. It is the most common form of arthritis, and a leading cause of disability in New Zealand. It is commonly referred to as ‘wear and tear of a joint’, but the process is more complex. The primary problem is breakdown of the cartilage within the joint which then leads to bony changes and damage to other surrounding tissues such as the ligaments.
Any joint can be affected but the most common joints are the joints at the base of the thumb, the distal finger joints in the hand, the big toe joint, the knees, the hips and the spine.
Symptoms include joint pain, stiffness and reduced movement. Cracking and grinding noises can occur with joint movement.
The main risk factors for developing OA are older age, being overweight, previous injury to a joint and a family history of osteoarthritis.
The diagnosis may be possible by examination alone, but often will require some form of imaging such as a plain x-ray or ultrasound. Blood tests are usually normal.
The goal of treatment in OA is to reduce pain and to improve function. Unfortunately, there are currently no medical therapies that can reverse cartilage damage. Pain relief can be obtained from heat packs, topical pain killers (e.g. diclofenac gel and capsaicin cream) and from oral pain killers.
Weight loss and exercise to strengthen the appropriate muscles can help symptoms.
The most effective oral pain killers are usually non-steroidal anti-inflammatory medications (e.g. diclofenac, ibuprofen, celecoxib, etc.), but they have potential serious side effects, so the risks need to be balanced with the benefit. Various supplements such as glucosamine sulphate, chondroitin, omega-3 fish oil, and turmeric may provide symptom benefit.
Joint injection with steroid (cortisone) or with hyaluronic acid (a lubricant product) can provide several months of symptom benefit and are generally safe treatment options which can be repeated as necessary if effective. In certain circumstances such as a single compartment of the knee having osteoarthritis - then a good brace to unload that compartment can provide pain relief.
Joint replacement surgery is reserved for end stage arthritis not responding to all the other treatment modalities.