Osteoarthritis Flashcards
osteoarthritis - defined
*mechanical degenerative disorder of joint cartilage caused by wear and tear
*occurs as joint cartilage thins, most often gradually over time
*pathogenesis: imbalance of destruction & repair of cartilage
osteoarthritis - epidemiology
*27 million Americans
*9.5% of adults > 60
*slightly more common in women
*most common in patients 65+
*most common form of arthritis
osteoarthritis - pathogenesis
*complex and not fully understood
*imbalance of destruction & repair of cartilage:
-chondrocytes produce cartilage matrix
-most of the effector molecules target chondrocytes
*genetic, physical, and lifestyle factors may contribute
osteoarthritis - risk factors
*increasing age
*female sex
*genetics
*obesity
*joint injury
*anatomic factors
osteoarthritis - clinical presentation
*non-inflammatory arthritis (<30 minutes of morning stiffness, worsens with use, improves with rest)
*pain = key feature
*loss of function and instability
*GELLING phenomenon (sitting for a long time, then get up, then pain goes away after 10-15 steps)
*affects larger weight bearing joints plus DIPs, PIPs, CMC joint, first MTP and mid-foot
classic joints in the hands that are affected by osteoarthritis
*disease affects:
1. DIPs (distal interphalangeal joints)
2. PIPs (proximal interphalangeal joints
3. CMC joint (at base of thumb)
4. also affects feet: first MTP, mid-foot
*disease SPARES: MCPs (contrast to RA)
osteoarthritis - physical exam findings
*may have some swelling
*bony overgrowth:
-Heberden nodules (bony enlargments of DIPs)
-Bouchard nodules (bony enlargement of PIPs)
-squaring of the CMC
osteoarthritis - diagnosis
*clinical findings
*labs typically are not abnormal (recall: ESR can rise with age, as can RF)
*non-inflammatory synovial fluid (synovial fluid WBC < 200)
radiology findings of osteoarthritis
*osteophytes
*ASYMMETRIC joint space loss/narrowing
*subchondral cysts
*subchondral sclerosis
contrast to RA, which has symmetric joint space loss
radiology findings of the hand in later osteoarthritis
*CENTRAL erosions
*“Gull Winging” pattern or sawtooth pattern
*only in DIPs and PIPs (spares MCPs)
osteoarthritis management - overview
*management, not treatment
*current treatment goals focused on:
-reducing pain and inflammation
-maintaining or improving joint mobility
-limiting functional impairment
-improving quality of life
non-pharmacologic osteoarthritis management
*exercise
*weight loss
*good footwear
*bracing or assist devices
*physical therapy
*patient education
pharmacologic management of osteoarthritis
*acetaminophen first
*NSAIDs second
*if acetaminophen and NSAIDs fail, consider:
-steroid injections
-intraarticular hyaluronic acid
-topical therapy
non-pharmacologic osteoarthritis management: EXERCISE
*strongly recommended by ACR
*high quality evidence
*low risk (esp. compared to medication)
1. land-based exercise
2. physical therapy (QUAD STRENGTHENING)
3. aquatic-based exercise (water aerobics, PT)
4. weight loss if patient is overweight
non-pharmacologic osteoarthritis management: other modalities
*conditional recommendation: assist devices, splints for CMC joints, medial wedge insoles for lateral compartment OA, Tai Chi, acupuncture
*NOT recommended: patellar taping, knee braces, lateral wedge insoles
pharmacologic osteoarthritis management: acetaminophen
*1000 mg TID
*advise to avoid more than 3000 mg
*first-line treatment for osteoarthritis
pharmacologic osteoarthritis management: NSAIDs
*used for those who fail acetaminophen
*COX-1 and COX-2 inhibitors that prevent arachidonic acid conversion, preventing formation of thromboxane A2, prostacyclins, etc
*ADEs: decreased renal blood flow, increased gastric acid production (increased risk of ulcerations and bleeding), increase BP
pharmacologic osteoarthritis management: topical NSAIDs
*topical diclofenac gel: indicated for pain of OA of hand and knee
pharmacologic osteoarthritis management: intra-articular steroids
*inject to decrease pain so that they can go to physical therapy and/or exercise
pharmacologic osteoarthritis management: intra-auricular hyaluronic acid
*subjective improvement (not proven by studies)
*works best (?) in patients with mild disease who still have cartilage present (does not work for bone-on-bone)
pharmacologic osteoarthritis management: opioids
*for knee, hip, or lower back pain
*not safer than giving NSAIDs; only given as last-resort
*no difference in pain score or functionality
*falls/fractures increased in OA patients on narcotics
surgery for osteoarthritis
*osteotomy
*joint replacement
general ADEs of NSAIDs
- decreased renal blood flow (renal toxicity)
- increased BP (slightly)
- increased risk of GI ulcers or bleeding (due to increased gastric acid production)
GI ADEs of NSAIDs
*GI toxicity is mediated mostly by COX-1 inhibition
*increased gastric acid production → increased risk of ulcerations, bleeding
*worse with: history of ulcers; concurrent use of aspirin, warfarin, other NSAIDs; age > 60; use of steroids
*can add a PPI if pt has risk
renal ADEs of NSAIDs
*increased BP (slightly)
*can interfere with anti-hypertensive effects of beta blockers, ACE inhibitors, ARBs, diuretics, etc
*can lead to renal insufficiency with chronic use
*caution if pt is already renally compromised
