OSTEOARTHRITIS

AKA "Degenerative joint disease," "Osteoarthrosis"

I. Epidemiology

  1. Prevalence increases w/age, most frequently starts in 40's
  2. Slight female predominance

II. Pathogenesis--multifactorial

  1. Thought to result from "normal stresses on abnormal cartilage or abnormal stresses on normal cartilage"
    1. Abnormal stresses include trauma, joint infection, and crystalline arthropathies but apparently not chronic aggressive exercise
  2. Genetic predisposition (perhaps leading to susceptible cartilage makeup) appears to be present

III. Clinical features

  1. Arthralgias worse with joint use, most commonly in PIP, DIP, carpometacarpal, and first MCP joints; also spine, hips, and knees
  2. Less stiffness than in inflammatory arthritides, e.g. rheumatoid arthritis
  3. Minimal signs of inflammation and no known extra-articular features
  4. Radiographic features (usually develop well in advance of sx): joint space narrowing, periarticular bone spur formation, subchondral bonen sclerosis

IV. Treatment

  1. Acetaminophen 4g/d may provide equal pain relief to Ibuprofen 1.2g/d with fewer side f/x for pts with mild-moderate but not severe pain from Osteoarthritis (J. Rheum. 28:1073, 2001--JW; Arth. Rheum. 44:1587, 2001--JW)
  2. NSAIDs
  3. Cox-2 Inhibitors
  4. Glucosamine sulfate (500mg TID)
  1. In vitro, stimulates cartilage cells to synthesize glycosaminoglycans and proteoglycans
  2. Effective (as much as ibuprofen 400mg TID) in relieving pain and increasing ROM in pts w/osteoarthritis in short-term placebo-controlled trials
    1. A meta-analysis of 15 such trials showed a sig. tx effect with glucosamine, as well as chondroitin (JAMA 283:1469, 2000--JW)
    2. In 98 pts with knee DJD, Glucosamine 500mg TID was not ass'd with any improvement in pain scores at 60d c/w placebo (West. J. Med. 172:95, 2000--AFP)
    3. A meta-analysis of 6 randomized trials found sig. effect on symptomatic and functional outcomes in glucosamine c/w placebo (also included analysis of 9 trials of chondroitin sulfate; JAMA 283:1469, 2000--abst)
    4. 212 pts with knee osteoarthritis randomized to glucosamine 1500mg QD vs. placebo; at 3y f/u, sig. diff. in loss of joint space and in symptom scores (favoring glucosamine) (Lancet 357:247, 2001--JW)
  3. Generally well tolerated; GI discomfort & nausea occur but at similar rates to placebo
  1. Chondroitin sulfate
    1. A component of articular cartilage
    2. In a meta-analysis of 7 randomized trials involving 703 pts w/knee- or hip osteoarthritis. Chondroitin was ass'd with sig. more pain reduction and imporvement in function than placebo. No significant adverse effects were noted. (J. Rheum. 27:205, 2000--JW)
    3. A meta-analysis of 9 randomized trials found sig. effect on symptomatic and functional outcomes in glucosamine c/w placebo (also included analysis of 6 trials of glucosaminesulfate; JAMA 283:1469, 2000--abst)
  1. Hyaluronan, intra-articular
    1. Derivative of hyaluronic acid; available commercially in 2 forms: sodium hyaluronate (Hyalgan) and hylan G-F 20 (Synivisc)
    2. Replaces natural hyaluronan which seems to have a protective effect on joints
    3. Shown to reduce knee osteoarthritis sx in short-term studies; very expensive as of 1998
    4. A randomized trial in 120 pts with knee OA showed no symptomatic improvement with intra-articular hyaluronan vs. placebo injections (Arch. Int. Med. 162:245, 2002--JW)
    5. In a meta-analysis of 22 RCT's of intra-articular hyaluronic acid for knee osteoarthritis, it was ass'd with only mild improvements in sx (JAMA 290:3115, 2003--JW)
  2. Ginger extract--261 pts with knee osteoarthritis randomized to ginger extract vs. placebo x 6wks; ginger pts had sig. greater likelihood of improvement of pain (63% vs. 50%) but also sig. more likely to have GI side f/x (45% vs. 16%) (Arth. Rheum. 44:2531, 2001--JW)
  3. Steroid Joint Injection
  4. Arthroscopic lavage & debridement--Not more effective than a sham procedure in a 2y randomized trial in 180 pts with knee osteoarthritis (NEJM 347:81, 2002--JW)
  5. Physical therapy--Ass'd with increased walking tolerance and decreased sx c/w placebo in a controlled trial of 83 pts with knee osteoarthritis (Ann. Int. Med. 132: 173, 2000--AFP)
  6. 87 pts with knee osteoarthritis randomized to therapeutic knee taping (designed to provide medial glide, medial tilt, and AP tilt to the patella and unload the infrapatellar fat pad and pes anserinus), control taping, or no taping.  At 3wks, therapeutic taping group had sig. greater reductions in pain & disability than the other two groups (BMJ 327:135, 2003--AFP)
  7. Joint replacement surgery as a last resort