High Yield Topics

Osteoarthritis

By admin



Ovid: 5-Minute Sports Medicine Consult, The


Osteoarthritis
Kevin deWeber
Basics
Description
A predominantly noninflammatory, slowly progressing, degenerative condition of articular cartilage, sometimes known as “degenerative joint disease”
Epidemiology
Prevalence
  • Radiographic osteoarthritis (OA) seen in about 40 million Americans, although only 10–30% of them have significant pain or disability.
  • Prevalence of symptomatic OA significantly increases with age and varies with affected joint (1):
    • Knee: 6% of adults >30, and 10–15% >60
    • Hip: 1–4% of adults
    • Hand: 10–15% of the elderly
Risk Factors
  • Systemic risk factors (1) contribute to development of OA by creating an environment where the joint is vulnerable:
    • Age (10-fold increase from 30–65 yrs of age)
    • Gender:
      • Men <50 have higher incidence than women (may be related to risk of joint injury)
      • Women >50 have higher incidence than men (possible protective role of estrogen is gone after menopause)
    • Genetics
    • Nutritional factors:
      • Lower risk of OA in persons with middle and highest tertiles of vitamin C intake or highest levels of vitamin D (Framingham data)
    • Ethnicity:
      • Chinese have lower rates of hip and hand OA.
      • African Americans have higher rates of hip and knee OA.
  • Joint biomechanical risk factors (1) cause direct trauma to articular cartilage:
    • Joint injury (fractures, dislocations, ligament and meniscal ruptures, articular surface damage)
    • Obesity (knee, hip, even hand OA)
    • Occupations involving high physical demands: Repetitive use of joints, heavy lifting, frequent squatting
    • Sports with significant risk of acute joint injury
    • Abnormal joint biomechanics (dysplasia, malalignment, instability, abnormal innervation)
    • Excessive running (>60 miles a wk) has relative risk of 2–12 times for hip OA (Systematic Review 2003)
Genetics
OA has a genetic component, especially in women. Primary, generalized OA is polygenic and multifactorial; environmental factors play a significant role in gene expression.
General Prevention
  • Avoidance of joint trauma
  • Weight management:
    • 50% reduction in OA risk with 11-lb weight loss in women (1)[C]
  • Adequate vitamin C and D intake (1)[C]
  • Avoid extremes of joint activity (joint immobilization or gross overuse)
  • Estrogen replacement after menopause may be protective (1)[C].
Etiology
  • OA is caused by an imbalance between breakdown and repair of joint tissue, usually due to multiple risk factors:
    • Cartilage matrix (collagen, water, proteoglycans) slowly degrades
    • Chondrocytes are unable to maintain adequate repair.
    • Mechanical forces contribute to progressive cartilage loss.
  • Early stages: Cartilage fibrillation (fine fraying)
  • Middle and late stages: Formation of extra subchondral bone and cysts and osteophytes (usually at joint margins)
  • Predominantly noninflammatory, but occasional mild inflammatory clinical flares
Commonly Associated Conditions
  • Degenerative meniscal tears in knee OA
  • Labral tears in hip OA
Diagnosis
  • Primary classification (idiopathic): Usually generalized
  • Secondary classification: Causes include previous trauma/internal derangement, metabolic disorder, and deposition diseases
  • Most commonly affected joints include the distal interphalangeal (DIP) and proximal interphalangeal (PIP) joints of the hands; metacarpophalangeal joints of the thumb; and the hallux, hips, knees, cervical, and lumbar spine
History
  • Insidious onset over months to years is typical.
  • Most common symptoms are pain (especially after excessive activity), crepitus or grinding, and joint swelling
  • There is typically short-lived (<30 min) stiffness after immobilization (ie, upon awakening), improving with mobilization.
  • Some patients experience muscular weakness in the surrounding soft tissue.
  • There may be a personal history of antecedent joint trauma or a family history of OA.
Physical Exam
  • Joint line tenderness is common in hands and knees.
  • Joints may have crepitus, decreased range of motion (ROM), effusion, and atrophy of surrounding muscles
  • In hands, may see nodules in the DIP and PIP joints, termed Heberden and Bouchard nodes, respectively
  • In the hips, decreased and painful internal rotation are early signs.
  • Severely affected joints may appear misshapen or deformed due to osteophytes or malalignment.
Diagnostic Tests & Interpretation
OA is diagnosed primarily through history and physical examination and confirmed by plain films.
Lab
  • Laboratory assessment only used to rule out other disorders, if clinically suspected:
    • CBC, chemistry profile, and urinalysis are normal.
    • Markers of inflammation (erythrocyte sedimentation rate, C-reactive protein) usually are normal, but may be slightly elevated during inflammatory flare-ups.
    • Rheumatoid factor and antinuclear antibody titers are negative.
Imaging
  • Plain films are the modality of choice (2)[D]:
    • Weight-bearing films are most sensitive in early knee and hip OA.
  • X-ray characteristics include osteophytes, joint space narrowing, subchondral sclerosis, and cyst formation.
  • Radiographic severity does not correlate with symptom severity.
  • CT and MRI do not play a large role in diagnosis of 0A. May be used if other conditions suspected.
Diagnostic Procedures/Surgery
Arthrocentesis and joint fluid examination are not routinely necessary unless the diagnosis is in question, there is a possibility of septic arthritis/crystal deposition disease, or for treatment of tense effusion.
Differential Diagnosis
  • Rheumatoid arthritis
  • Collagen vascular diseases
  • Crystal deposition disease
  • Gout
  • Calcium pyrophosphate deposition disease
  • Meniscal or labral tears
Treatment
  • Optimal management requires a combination of nonpharmacological and pharmacological modalities (3)[D].
  • A multidisciplinary approach may help patients make the most of available therapies:
    • Providers, physical therapists, personal exercise trainers, health care educators, nutritionists
  • Surgical therapy is best reserved for patients with severe pain that affects quality of life or activities of daily living who have failed multiple conservative measures (3)[C].

P.425


Medication
No disease-modifying agents are yet available.
First Line
  • Acetaminophen (up to 4 g/day) is modestly effective and should be encouraged as the first-line medication due to its relative safety (3)[A].
  • Oral glucosamine sulfate (not hydrochloride) 1,500 mg/day is modestly effective in reducing pain in some patients (3)[A]:
    • Use for several years can slow progression of joint space narrowing; consider use even if no symptomatic benefit (3)[A].
  • Oral NSAIDs effective, but have higher risks; reserved for short-term therapy (3)[A].
    • COX-2 inhibitors are not more effective; less GI toxicity, but not without risks.
    • Discourage chronic use of NSAIDs; if necessary, add gastroprotection with a proton pump inhibitor or misoprostol.
  • Viscosupplementation with intra-articular injection of hyaluronate derivatives is modestly effective in pain reduction (3)[A]:
    • 3–5 weekly injections
    • 2–5-wk delay in effects
    • 1–6-mo duration of effects
Second Line
  • Tramadol 50–100 mg t.i.d. is effective but has sedating and constipating properties similar to narcotics (3)[A].
  • Topical NSAIDs are effective; effect takes 1–2 wks (3)[A].
  • Topical capsaicin is effective; high incidence of local irritation (3)[A].
  • Weak opioids or narcotics can be considered for short-term refractory pain; those requiring long-term use may benefit from maximization of nonpharmacologic therapies and/or surgery (3)[A].
  • Intra-articular injections with corticosteroids are effective for 2–4 wks (3)[A]:
    • Reserve for patients not responding to oral medications or inflammatory flare-ups.
    • Limit to 2–3 injections per year per joint.
    • Observe for significant incidence of systemic side effects.
Additional Treatment
General Measures
  • Patient education is effective (3)[A]:
    • Set reasonable expectations on outcome (pain reduction, increased function, not cure)
    • Modification of activities to minimize pain and risk of joint trauma
    • Importance of nonpharmacologic therapies
  • Weight reduction is paramount (3)[A].
  • Aerobic conditioning with nonpainful activities (walking, deep-water running and other aquatic exercise, cycling) (3)[A]
  • ROM and muscle strength exercises are effective (3) for hip [D] and knee [A] OA.
  • Physical therapy referral may be effective (3)[D].
  • Walking aids for knee and hip OA may be effective (cane, crutch in contralateral hand; walkers for bilateral OA) (3)[D].
  • Knee brace for patients with varus or valgus instability improves stability and reduces fall risk (3)[A].
  • Footwear with lateral wedge insoles for medial knee compartment OA (3)[A]
Complementary and Alternative Medicine
  • Thermal therapies (heat, cold) may be effective (3)[A].
  • Transcutaneous electrical nerve stimulation can provide short-term relief (3)[A].
  • Acupuncture may be effective in knee OA (3)[A].
  • Pulsed electromagnetic field therapy may be effective in improving function 4 [A].
  • Balneotherapy (spa, mineral baths) may be effective 5 [A].
  • Static magnets: No evidence for support; effectiveness cannot be ruled out 6 [A].
  • Intra-articular autologous platelet-rich plasma injection: Success in 1 series; under study
Surgery/Other Procedures
  • Indicated in patients with recalcitrant pain and interference with activities of daily living despite maximizing conservative management (3)[C]
  • Arthroscopic lavage and debridement NOT effective (3)[A]; only indicated for concomitant non-OA conditions
  • Medial or compartment knee OA:
    • Wedge osteotomomy may be effective (7)[B].
    • Unicompartmental arthroplasty (replacement) effective (7)[B]
    • Interposition arthroplasty (joint spacer insertion); no data on safety/efficacy
  • Total knee arthroplasty (TKA): Very effective (3)[C]:
    • Hardware durable 10–15 yrs
    • Try to delay TKA until after 55 by maximizing other treatments.
    • Rate of hardware failure <10 yrs is 3 time in <55 vs >70 yrs of age
  • Patellofemoral joint (PFJ) OA in isolation (rare):
    • Elevation of tibial tubercle may be effective
    • PFJ arthroplasty sometimes used
  • Total hip arthroplasty or joint resurfacing is effective in hip OA (3)[B].
  • Glenohumeral OA: Total shoulder replacement more effective/durable than humeral head replacement (8)[B], but both are effective.
  • Cartilage replacement techniques gaining in popularity and evidence:
    • Autologous cartilage implantation: Arthroscopy harvests patient's cartilage, chondrocytes are replicated in culture, and 2nd arthroscopy fills cartilage defect with cells.
    • Osteoarticular cartilage transplant: Cartilage from patient's nonweight-bearing surface in knee joint is placed into defect.
    • Cartilage allografts (cadaver cartilage) to fill defects
Ongoing Care
Follow-Up Recommendations
As needed based on symptoms and function
Diet
Ensure adequate vitamin C and D intake.
Patient Education
Good education has proven benefit for successful management:
  • In office by professionals
  • Public education materials (eg, www.myosteoarthritiscentral.com)
Prognosis
  • OA is a progressive arthropathy with highly variable course
  • Oral glucosamine shown to slow rate of radiographic progression over >3 yrs
References
1. Garstang SV, Stitik TP. Osteoarthritis: epidemiology, risk factors, and pathophysiology. Am J Phys Med Rehabil. 2006;85:S2–S11.
2. American College of Radiology Expert Panel on Musculoskeletal Imaging, 2008. http://74.125.93.132/search?q=cache:Up16N8YvlbEJ:www.acr.org/SecondaryMainMenuCategories/quality/safety/app/criteria/pdf/ExpertPanelonMusculoskeletalImaging/nontraumaticKneePainDoc15.aspx+american+college+of+radiology+panel+on+musculoskeletal+imaging+osteoarthritis&cd=1&hl=en&ct=clnk&gl=us.
3. Zhang W, Moskowitz RW, Nuki G, et al. OARSI recommendations for the management of hip and knee osteoarthritis, Part II: OARSI evidence-based, expert consensus guidelines. Osteoarthritis Cartilage. 2008;16:137–162.
4. Vavken P, Arrich F, Schuhfried O, et al. Effectiveness of pulsed electromagnetic field therapy in the management of osteoarthritis of the knee: A meta-analysis of randomized controlled trials. J Rehabil Med. 2009;41:406–411.
5. Harzy T, Ghani N, Akasbi N, et al. Short- and long-term therapeutic effects of thermal mineral waters in knee osteoarthritis: a systematic review of randomized controlled trials. Clin Rheumatol. 2009;28:501–507.
6. Pittler MH, Brown EM, Ernst E. Static magnets for reducing pain: systematic review and meta-analysis of randomized trials. CMAJ. 2007;177:736–742.
7. Richmond JC. Surgery for osteoarthritis of the knee. Med Clin North Am. 2009;93:213–222.
8. Radnay CS, Setter KJ, Chambers L, et al. Total shoulder replacement compared with humeral head replacement for the treatment of primary glenohumeral osteoarthritis: A systematic review. J Shoulder Elbow Surg. 2007.
Codes
ICD9
  • 715.91 Osteoarthrosis, unspecified whether generalized or localized, involving shoulder region
  • 715.92 Osteoarthrosis, unspecified whether generalized or localized, involving upper arm
  • 715.93 Osteoarthrosis, unspecified whether generalized or localized, involving forearm


Continue Reading
You might also like More from author

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept Read More