Weight loss and exercise are the mainstay of all treatments of osteoarthritis. All therapies for the treatment of osteoarthritis should be combined with a weight loss and exercise program, wherever possible. However, although exercise therapy has short-term benefits for pain and physical function in patients with knee OA, effectiveness has been shown to decline over the longer term due to poor adherence (Pisters et al, 2007).
Oral pain relieving therapies, such as paracetamol and anti-inflammatory medication aim to minimise the pain of the disease, but do not address the underlying processes driving OA (Sampson et al, 2010). Not surprisingly therefore, these treatments have poor long-term success and are associated with side effects that increase with long-term use (Bjordal, Ljunggren, Klovning, & Slørdal, 2004). In addition, the recently highlighted increased heart attack and stroke risk associated with the use of anti-inflammatories, significantly decreases their previous appeal (Fosbøl et al, 2010).
The injectable pain relief options include cortisone, Hyaluronic acid and platelet rich plasma. Cortisone is a well accepted means of controlling the pain of osteoarthritis, and although its big brother prednisone, gives it a bad name, it has quite a low side effect profile and is good especially during periods of acute pain. The problem is that is wears off relatively quickly and only gives on average 3 weeks pain relief when used for knee osteoarthritis (Habib et al, 2010). Hyaluronic acid is known as viscosupplementation. It acts as a local anti-inflammatory for the joint and settles pain. Its pain relieving effect come on over 3 months and will generally last 6 or more months. People with lower degrees of osteoarthritis do better than those with severe disease. It has been extensively researched with varying results.
The final injectable option is platelet rich plasma (PRP). There is currently 4 scientific papers that support its’ use in osteoarthritis. Two papers have followed patients up to 2 years with positive results (Baltzer et al, 2009, Filado et al, 2010), and 2 papers have compared it to hyaluronic acid and shown platelet rich plasma to have greater pain relieving effects (Baltzer et al, 2009, Sanchez et al, 2008). PRP requires on average 3 injections to have a significant effect with a gradually increasing effect after each injection. The pain relieving effect anecdotally lasts for about 11 months. PRP does hold some promise as a new therapy for osteoarthritis but is still considered experimental.
Surgical intervention is common given the progressive nature of the disease; however, a recent review of the literature concluded that there was no benefit from arthroscopic debridement for osteoarthritis (Laupattarakasem et al, 2008). The final surgical step is joint replacement. The increase in demand for this treatment has resulted in a significant burden on the healthcare system (March & Bagga, 2004). Consequently, there is a pressing need for novel and effective therapies to treat OA.
