Epidemiology of OA
Osteoarthritis (OA) is the most common form of arthritis. Evidence of OA is present in the majority of people over age 65 y.Definition of Osteoarthritis
“Osteoarthritis is a degenerative joint disease.Characterized by erosion of the articular cartilage, hypertrophy of bone at the margins (osteophytes), and sub-chondral sclerosis.And a range of biochemical and morphologic alterations of the synovial membrane and joint capsule. Harris: Kelley's Textbook of Rheumatology, 7th ed.“Despite its prevalence, the precise etiology, pathogenesis, and progression of OA remain beyond our understanding…”
Associated Risk Factors
Age Female versus Male sex Obesity Osteopenia Occupation Sports Activities Prior injury Muscle weakness Acromegaly Calcium crystal deposition diseaseClinical Features
Joints Affected: Hand interphalangeal joints, spine, knees, hips, and first MTP. Symptoms:joint pain worsens with use and is alleviated with rest, stiffness, crepitus, functional impairment. Signs: limp, deformity, alteration in joint shape, muscle atrophy, weakness, increased effusion, crepitus, restricted movement, joint line and peri-articular tenderness, bony swelling, soft tissue swelling.Radiographic Appearance
Radiographic Criteria: Loss of joint space Subchondral sclerosis or cyst formation Presence of new bone formation or osteophytes .Do weight loss improve OA?
For a woman, weight loss of only 5kg reduces the risk of OA by more than 50%. Estimated that weight loss could prevent 33% of OA in women and 20% in men. Obese women had an odds ratio of 8.57 for radiographic and symptomatic OA of the knee.
Tylenol
Is acetaminophen effective for Osteoarthritis? Is acetaminophen the drug of choice? Is it safe?Acetaminophen has clearly been demonstrated to be effective in the treatment of the pain of OA when c/w placebo, with a NNT of 3.6 for 50% pain reduction when using 1000mg.
Acetaminophen is the drug of choice in both the ACR and EULAR guidelines.
Acetaminophen has been demonstrated to be safe in doses up to 4gm/day.
Traditional NSAIDs
Are NSAIDs more effective than acetaminophen? Are some NSAIDs more efficacious than others? Do NSAIDs destroy cartilage in the long term?Cochrane Review 1997: no evidence to assess clinical differences among the various NSAIDs. Decisions should be made upon safety, acceptability and cost.
Consensus expert opinion and clinical data appear to state that in the treatment of mild No…as OA is principally non-inflammatory NSAIDs should clearly be titrated for clinical effect.to moderate osteoarthritis acetaminophen and NSAIDs have comparable efficacy. There is no reliable evidence in human models by clinical trials that NSAIDs are either chondroprotective or chondrodestructive.
New FDA Recommendations
News The three COX2 agents are associated with an increased risk of adverse CV events c/w placebo. Data from large clinical trials,CV risk of the COX2 equal to the non-selective NSAIDs. The COX2 agents reduce the incidence of GI ulcers visualized at endoscopy.Issues With Aspirin Use
Evidence (from CLASS) suggests that aspirin use, even in low doses, is a more important risk factor for the occurrence of upper GI events than was anticipatedOpioids
Is there a role for opioid analgesia in osteoarhtritis? Is there a role for chronic therapy with opioid analgesics?Yes…all the guidelines and UpToDate recommend considering narcotic analgesia for acute exacerbations unresponsive to conventional therapy. Tramadol is specifically identified by the ACR as well as UpToDate as the initial agent of choice. Yes…some patients may require chronic therapy with opioids. ACR guidelines support opioid therapy when other treatments have failed or are not appropriate. American Pain Society guidelines for nonmalignant pain should be followed.
Steroid Injections – The Evidence Pain and inflammation decreases for only 2-4 weeks. Very little comlication 1:15 000 - 1: 50 000 No evidence for cartilage destruction, even upon repeativie injections Patients should be informed about the above evidence Can be done at the start, while waiting NSAIDs for action.
Braces and Heel Wedges
Principal purpose is to reduce pain, assist function, and prevent disease progression. Action by alterations of biomechanical force loads.Heel Wedges
Wedges are thought to assist patients with medial compartment osteoarthritis by mechanically decreasing the varus torque.Braces
Valgus or unloader braces are thought to assist patients with medial compartment osteoarthritis with a significant varus deformity.EBM 2010 Glucosamine and chondroitin have individually and collectively shown inconsistent efficacy, even in meta-analyses, in decreasing knee pain and improving joint function associated with OA. The literature consistently demonstrates an excellent safety profile of these agents. These agents may be safely tried as an initial therapy in selected OA patients prior to initiating therapy with other modalities of treatment. They are not proved yet by FDA.