Osteoarthritis Flashcards
Osteoarthritis
-Inflammation of bone + cartilage
-Structural and functional failure of synovial joints
-Muscle weakness results in joint pain, instability, and functional limitations
What are the risk factors of OA?
i. Advanced age
ii. Female
iii. Obesity
iv. History of joint trauma
v. Lack of osteoporosis
vi. Repetitive motion
vii. Previous occupation
viii. Sports
ix. Genetics
x. Diabetes
xi. Quadriceps weakness
xii. Calcium crystal deposition disease
What is the most preventable risk factor?
Obesity
What is the pathophysiology of OA?
Damage to the cartilage–> increase chondrocyte activity = cartilage swelling–> increase water content = cartilage thickening–> increased MMP (mediator tumorigenesis) secretion–> proteoglycan breakdown–> increase cartilage permeability and destruction bony remodeling
What are the symptoms of OA?
- Nearly all patients have pain in the affected joints (hands, knees, and hips being the most common)
- Pain is most commonly associated with motion, but pain in late disease can occur with rest
- Morning joint stiffness (usually < 30 mins) resolves with motion; recurs with rest
What are the signs of OA?
- Crepitus, a crackling or grating sound heard with joint movement that is caused by irregularity of joint surfaces may be present
- Limited range of motion that may be accompanied by joint instability
- Late stage disease is associated with joint deformity
- Heberden (protrusion of DIP) and Bouchard (protrusion of the interphalangeal) nodes extra bony protrusions
What are some test you can do for OA?
- Radiologic test
- Joint space narrowing, appearance of osteophytes (bone spurs)in moderate disease
- Abnormal alignment of joints and joint effusion in late disease
What is strongly recommended for hand OA?
Oral NSAIDs
What is conditionally recommended for hand OA?
- Topical NSAIDS (preferred over PO for those > 75 years old)
- Intraarticular steroids
- Acetaminophen
- Duloxetine
- Tramadol
- Chondroitin
What is conditionally recommended against hand OA?
- Non-tramadol opioids
- Colchicine
- Fish oil
- Vitamin D
- Topical capsaicin
What is strongly recommended against hand OA?
- Bisphosphonates
- Glucosamine
- Hydroxychloroquine
- Methotrexate
- Biologics
What is strongly recommended for knee OA?
- Topical NSAIDs
- Oral NSAIDs
- Intranasal steroids
What is conditionally recommended for knee OA?
- Topical capsaicin
- Acetaminophen
- Duloxetine
- Tramadol
What is conditionally reocommended against knee OA?
- Non-tramadol opioids
- Colchicine
- Fish oil
- Vitamin D
What is strongly recommended against hip OA?
- Bisphosphonates
- Glucosamine
- Chondroitin
- Hydroxychloroquine
- Methotrexate
- Biologics
What is the MOA of Acetaminophen?
Inhibition of central prostaglandin synthesis
What is the MOA of NSAIDs?
Block prostaglandin synthesis via inhibition of COX1/COX2
What are drug drug interactions with NSAIDs?
warfarin, clopidogrel, SSRIs, ASA
What are some risk factors for GI injury due to NSAIDs?
a. History of GI bleeding
b. Antiplatelet drugs (including aspirin)
c. Age > 70
d. Multiple NSAIDs
e. History of peptic ulcer
f. Anticoagulant drugs
g. Chronic steroid use
h. Dyspepsia
What do you give high-risk patients when they’re on NSAIDs?
- Add daily PPI
- Preferred, most evidence to support
- Add misoprostol 200 mcg QID
- Add full dose H2RA (least evidence to support)
- Sucralfate not recommended
Voltaren (Diclofenac) 1% Gel
- Commonly used topical NSAIDs
- Reduces pain/stiffness in hand and knee
What is the max dose of Voltaren (Diclofenac) 1% Gel?
Total body dose should not exceed 32 g/day
or for more than 21 days on more than 1 body part
What is the adverse effects of Voltaren (Diclofenac) 1% Gel?
- Local burning
- Stinging
- Erythema
- Systemic absorption (6-10% of oral dose)
What are some topical NSAID Pearls?
- Works well as PO NSAIDs on localized areas
- Reduces long term PO NSAIDs
- Lower risk for systemic side effects
- Combination with PO NSAID no better than oral NSAID alone
Tramadol
MOA: Binds to mu-opioid receptor + inhibits reuptake of norepinephrine and serotonin
* Partial opioid agonist
What is the max dosing of tramadol?
- 400 mg/daily
- For elderly, 300 mg/daily
What are the adverse effects of Tramadol?
- Sedation
- Constipation
- Can potentially lower seizure threshold
Duloxetine (Cymbalta)
- MOA: Selective norepinephrine reuptake inhibitor (SNRI)
- Approved for chronic musculoskeletal pain
- Reduces pain and improves function with knee OA
When would you consider Duloxetine?
- Neuropathic component to pain
- Concomitant depression
- Inadequate response or contraindications to other agents
What are the adverse effects of Duloxetine?
- Nausea
- headache
- dizziness
- sleep disturbances
- sexual dysfunction
- urinary retention
What are some clinical pearls of Duloxetine?
- Moderate CYP2D6 inhibitors
- Interacts with SSRIs, NSAIDs, tramadol
- Renally limited (not recommended with CrCl < 30 mL/min)
Capsaicin
MOA: Derived from hot peppers. Releases and ultimately depletes substance P from different nociceptive nerve fibers (pain transmission)
What is the patch formulation of Capsaicin?
- Apply 1 patch to affected area for up to 8 hours (max 4 patches/day)
- Do not use more than 5 consecutive days
What are the adverse effects of Capsaicin?
- Stinging
- itching
- erythema
- burning
Glucosamine/chondroitin
- Normal components of cartilage
- MOA: Used in proteoglycan synthesis
-Slow onset—symptom reduction in 2 months
-Discontinue after 6 months if no response
What are the local side effects of intraarticular injections?
- Post-injection pain flare
- Crystal synovitis
- Hemarthrosis
- Joint sepsis
- Articular cartilage atrophy
What are the systemic side effects of intraarticular injections?
- Hyperglycemia
- Weight gain
- Osteoporosis
- Fluid retention
