Friday, March 19, 2010
hand osteoarthritis
Introduction
Hand osteoarthritis (OA) has an estimated prevalence of 20% to 30% [1,2], making the hand the second most frequent site of OA pain [1,3]. The prevalence of hand OA increases with age, surpassing 50% after patients reach the age of 60 years [4-6]. Symptoms include not only pain but also functional impairment in the form of stiffness, reduced grip strength, reduced hand mobility, and difficulty performing dexterous tasks [2,4,7,8].
Function is irreversibly compromised in OA of the hand as articular surfaces are eroded and deformed. In OA of the knee and hip, a definitive improvement in function can be obtained with surgical replacement of the joint, but prosthetic joints have been less successful for hand OA [9]. More often, surgery for hand OA may be performed for cosmetic reasons rather than to provide functional improvement (for example, patients self-conscious of and eager to remove Heberden nodes).
Nonsteroidal anti-inflammatory drugs (NSAIDs) are recommended for the management of pain in patients with hand OA who do not respond to physical measures and acetaminophen [10]. Though effective for the treatment of mild to moderate OA pain [11], NSAIDs have been associated with an increase in the risk of serious gastrointestinal adverse events, including ulcers, perforations, and bleeding related to dose and duration of use [12,13]. The potential risk of cardiovascular [14-16] and renal [17,18] adverse events with NSAIDs is also considered exposure-related and generally observed during long-term NSAID therapy.
Treatment guidelines recommend topical NSAIDs as effective monotherapy for relief of OA pain in superficial joints, such as those in the hands [10], with the potential to mitigate the risk of NSAID-related adverse events by reducing systemic NSAID exposure. Topical diclofenac sodium 1% gel provided safe and effective pain relief compared with placebo in a large clinical trial in patients with hand OA [19]. Administration of diclofenac sodium 1% gel results in substantially lower systemic diclofenac concentrations than occur following oral administration [20].
NSAIDs relieve OA pain but are not believed to alter the underlying changes that produce biomechanical limitations of physical function in OA. However, other interventions that provide symptomatic relief without altering underlying structural changes, such as opioids, have been associated with improvement of physical function in OA of the knee and hip [21]. This finding suggests that in addition to the biomechanical limitations caused by hypertrophic changes in OA, it is possible that pain or the anticipation of pain leads to voluntary and involuntary restriction of activity [22]. If this is true, relief of pain alone may improve physical function in OA although no biomechanical improvement has occurred. In the present analysis, we tested the hypothesis that pain relief is associated with improved physical function in patients with hand OA.
