17 - Osteoarthritis Flashcards
Increased burden of disease due to ?? (2 things)
- increasing age of population
- increasing obesity rates
Describe the burden of osteoarthritis
- public health care system burden
- burden on QOL
Define OA
Joint pain that occurs for most days of the prior month plus radiographic changes in the symptomatic joint
What joints are affected?
impacts any joint, but typically is in the spine (cervical or lumbar), hands, hip and knees
What is primary OA?
- idiopathic (unknown cause)
- often the elderly
What is secondary OA?
- joint insults (trauma, infection)
- rheumatoid arthritis
- gout
- congenital joint abnormalities
- hematological genetic abnormalities (leukemia)
List 4 things that protect the joint
1) Synovial fluid - nourishment (physical protectant) - prevents friction
2) Ligaments and tendons - joint protection mechanism
3) Bone - shock absorbing effects
4) Cartilage - creates frictionless surface, impact-absorbing quality
What happens in OA?
There is an imbalance between repairing and synthesizing new cartilage.
*Imbalance between cartilage destruction and cartilage formation!
The remaining cartilage is softened and develops fibrillations and then you have exposure of the actual bone. Bones become more brittle and can have minor fractures. There are also changes to the synovium.
Is OA part of normal aging?
no way jose
What play a role in cartilage destruction?
IL-1 and metalloproteases
What is involved in the formation of osteophytes?
Local growth factors, especially TGF (transforming growth factor)
What is an osteophyte ?
a bony outgrowth associated with the degeneration of cartilage at joints
Risk factors for OA (list a few, more on slide 11)
- age
- obesity
- nutrition
- joint injury
- physical activity
- muscle weakness
- women more at risk than men
Describe the diagnosis of OA
CLINICAL diagnosis:
-No further tests if: >45 yo + activity-related join pain + morning joint stiffness < 30 mins or non-existent
What are lab tests used for in OA?
to rule out other causes of symptoms (ex. gout or RA)
What are radiographs and joint aspiration useful for?
red, hot, swollen joints
List symptoms of OA
- Stiffness: morning or after periods of inactivity that lasts less than 30 mins
- Symptoms localized to the affected joint
- Pain worse with activity (especially weight bearing) or prolonged use
List signs of OA
- Often unilateral, occasionally symmetrical
- Joints are not usually tender or inflamed
- Joint instability may be present
- No systemic symptoms
What is the pain in OA related to?
- Not related to destruction of cartilage
- From activation of nociceptive nerve endings within the joint by mechanical and chemical irritants
- May be due to distension of the synovial capsule by increased joint fluid, micro fracture, periosteal irritation, or damage to ligaments, synovium or the meniscus
Describe the physical exam of OA
- pain, stiffness, and limitation of both passive and active movement of the joint
- crepitus, deformity, muscle atrophy, ligament tenderness in one or more of the affected joints
- ligament and capsular laxity + muscle atrophy = joint instability (later leading to deformity)
Why don’t we X-ray everyone?
the results of an x-ray do not influence clinical management
What does an X-ray look for?
- narrowing of joint space (due to loss of cartilage)
- osteophytes
- bone cysts
What types of nodes can be involved in OA?
1 - Heberden nodes
2 - Bouchard nodes
When will you refer ?
- new onset of joint pain
- duration of symptoms > 7-10 days
- recent trauma
- systemic symptoms
- injury due to sports
- local or diffuse muscle weakness
- symptoms of burning, numbing, tingling
- inflammation of joints
- morning stiffness > 1 hr
- drug-related
- chronic liver disease or history of inflammatory arthritis
Who can we recommend products for?
patient with DIAGNOSIS of OA seeking self management
What do we first recommend?
Non-pharms (physiotherapist, exercise, weight loss)
After non-pharms, we start with ?
OTC recommendations
What pain scale is recommended for OA patients?
WOMAC questionnaire (slide 22) -determines severity of pain
Goals of therapy for OA ?
- relieve or eliminate pain (and stiffness)
- improve or restore joint function and mobility
- improve muscle strength to protect cartilage, ligaments and joint capsule
- prevent and reduce damage to the joint cartilage, bone, ligaments, muscles, and nerves
- maximize QOL
- educate the patient/caregiver to promote adherence
Treatment of OA:
If not enough pain relief from non-pharms, what do we try?
acetaminophen up to 1g QID
Treatment of OA:
If not enough pain relief from acetaminophen, what do we try?
-add topical diclofenac
Treatment of OA:
If not enough pain relief from adding topical diclofenac, assess risk factors for ___ events.
GI
Treatment of OA:
If they have no risk factors for GI events, try ?
low dose non-selective NSAID
Treatment of OA:
If they have 1-2 risk factors for GI events, try ?
low dose non-selective NSAID
+
gastroprotection
OR
low-dose Cox-2 inhibitor
Treatment of OA:
If they have multiple risk factors for GI events, try ?
alternative therapy (ex. local injections, duloxetine, opioids)
OR
low dose cox-2 inhibitor + gastroprotection
Treatment of OA:
If they’re on a low dose NSAID with or without gastroprotection, and not enough relief, what do we do?
try full-dose
Treatment of OA:
If they’re on a full dose NSAID with or without gastroprotection, and not enough relief, what do we do?
surgery
What are some risk factors for GI events?
- ppl > 60
- on high dose NSAID already
- history of upper GI bleed
- presence of H. pylori infection
For Hand OA:
What are some non-pharms?
- assist devices
- instruct on joint protection techniques
- thermal modalities (hot/cold therapy)
- splints
For Hand OA:
What are some charms?
- topical capsaicin
- topical NSAIDs
- oral NSAIDs (including cox-2 selective inhibitors)
- tramadol
*all conditional - no strong recommendations
For Hand OA:
Don’t use _______
acetaminophen
For Hand OA:
Patient > 75:
What are first line agents?
-topical NSAIDs or -topical capsaicin and/or -tramadol
For Hand OA:
Patient > 75:
What we do we try if first line agents are not effective?
combine therapy or two first line agents (i.e. topical NSAIDs and tramadol)
For Hand OA:
Patient < 75:
What are first line agents?
- oral NSAIDS (if low CV and GI risk
- topical NSAIDs
- topical capsaicin and/or tramadol
For Hand OA:
Patient < 75:
What we do we try if first line agents are not effective?
combined therapy with two first line agents (i.e. oral NSAIDS and topical capsaicin or tramadol)
For Knee OA:
What are some strong non-pharms?
- CV (aerobic) and/or resistance land-based exercise
- aquatic exercise
- lose weight (for those overweight)
For Knee OA:
What are some pharmacological agents?
- acetaminophen
- topical NSAIDs
- oral NSAIDs
- tramadol
- intraarticular corticosteroid injections
For Knee OA:
What do we recommend against?
- chondroitin sulfate
- glucosamine
- topical capsaicin
For Hip OA:
What are some non-pharms?
- participate in CV and or resistance land based exercise
- aquatic exercise
- lose weight for those overweight
(same as knee OA)
For Hip OA:
What are some pharmacological agents?
- acetaminophen
- intraarticular corticosteroid injections
- oral NSAIDs
- tramadol
For Hip OA:
What do we recommend against?
- chondroitin sulfate
- glucosamine
- topical capsaicin
For Knee and Hip OA:
What is there no recommendation for ?
- intraarticular hyaluronates
- duloxetine
- opioid analgesics
For Knee and Hip OA:
What do we start with?
acetaminophen
For Knee and Hip OA:
If acetaminophen isn’t effective, what do we try?
- opioid analgesics
- surgery
- duloxetine (knee only)
- intraarticular hyaluronates
For Knee and Hip OA:
If acetaminophen is CI, what do we try? (alternative first line agents)
-topical NSAIDs (knee only), and/or
-intraarticular corticosteroids
and/or
-tramadol
and/or
-oral NSAIDs if <75 or low CV and GI risk
For Knee and Hip OA:
If the alternative first line agents fail, what do we try?
- opioid analgesics
- surgery
- duloxetine (knee only)
- intraarticular hyaluronates
Non-pharms for OA
- exercise
- weight loss
- heat/cold therapy
- massage
- surgery
Acetaminophen:
What dose do we use of regular release?
325-1000mg PO Q4-6 hours
Max 4g/day
Acetaminophen:
What dose do we use of sustained release?
650mg PO q8h
Max 4g/day
Acetaminophen:
How long should therapy be tried before assessing affect?
2 weeks
Acetaminophen:
MOA?
inhibits PG synthesis through inhibition of COX-2 enzyme
Acetaminophen:
Role in OA?
first line (except in hand)
first line for non-inflammatory OA
Acetaminophen:
Efficacy?
-in mild, non-inflammatory OA, it is equivalent to NSAIDs
-less effective than NSAIDs in inflammatory/advanced OA
(acetaminophen < analgesic dose NSAID < anti-inflammatory dose NSAID)
Acetaminophen:
Max dose for those > 75 yo
3.2g/day
Acetaminophen:
Avoid ____
alcohol
Acetaminophen:
Enhanced hepatotoxicity with _____
warfarin
Capsaicin:
Dose
apply sparingly 3-4 times/day for 3-4 week period to achieve max therapeutic effect
Capsaicin:
MOA
-capsaicin renders skin and joins insensitive to pain by depleting and preventing reaccumulation of substance P in peripheral sensory neurons so that local pain impulses cannot be transmitted to the brain
Capsaicin:
Role in OA?
first line, esp for non-inflammatory OA
*not for hip bc we don’t use topical meds on hip
Capsaicin:
SE?
tingling, burning or redness (in majority of patients)
Topical diclofenac:
MOA
inhibits PG synthesis through Cox-1 and Cox-2 pathways
Topical diclofenac:
Role in OA?
- second line in OA due to safety
- can be used first line in there is an inflammatory component to the OA
Topical diclofenac:
SE?
minimal bc of limited systemic bioavailability
Which Cox enzyme is involved in gastroprotection?
Cox-1
- Therefore if you inhibit it, you increase risk for GI effects
- Cox-2 selective inhibitors are safer for ppl with GI risk
What drug negates the gastroprotective effect of cox-2 selective inhibitors ?
ASA (bc it inhibits Cox-1 as that is the enzyme involved in platelet aggregation)
What cox enzyme(s) are inhibited by corticosteroids?
cox-2
What is Cox-1 involved in?
- PGs
- Thromboxanes
Involved in:
- gastroprotection
- platelet aggregation
- renal function
What is Cox-2 involved in?
-PGs
Involved in:
-pain, fever, renal function, tissue repair, reproduction, development
If a patient requires NSAIDs and has a high GI risk with high CV risk (on ASA), what do we do?
- avoid NSAID if possible
- if can’t avoid NSAID, and have very high CV risk, use naproxen + PPI
-if can’t avoid NSAID, and have a very high GI risk, use cox-2 inhibitor + PPI
If a patient requires NSAIDs and has a high GI risk with low CV risk, what do we do?
cox-2 inhibitor alone or topical NSAID
+
PPI
If a patient requires NSAIDs and has a low GI risk with high CV risk (on ASA), what do we do?
naproxen + PPI
If a patient requires NSAIDs and has a low GI risk with low CV risk, what do we do?
topical NSAID
IA Steroids:
Methylprednisolone acetate (depo-medrol)
Dose?
10-20 mg per joint
20-80mg per large joint (knee, hip, shoulder)
IA Steroids:
Triamcinolone acetone (Kenalog)
Dose?
5-15 mg per joint
10-40 mg per large joint (knee, hip, shoulder)
IA Steroids:
MOA
anti-inflammatory properties for pain relief
IA Steroids:
Role in OA?
alternative first line Tx for both knee and hip OA when pain control with acetaminophen or NSAIDs is suboptimal or offered concomitantly with oral analgesics
IA Steroids:
Efficacy?
- superior to placebo
- benefits only last 4-6 weeks tho
IA Steroids:
Adverse effects?
- hyperglycemia
- edema
- HTN
- flushing
- dyspepsia
- hypercortisolism
IA Hyaluronic acids:
Dose of sodium hyaluronate?
- 1 injection into the involved joint
- may be given once only or weekly for 3-5 weeks
IA Hyaluronic acids:
MOA
synovial fluid replacement/replenishment
IA Hyaluronic acids:
Role in OA?
not routinely recommended
IA Hyaluronic acids:
Efficacy?
limited efficacy and risks of serious events limit the routine use of these agents
Duloxetine:
Dose
60mg once daily
max dose = 120 mg/day
Duloxetine:
MOA
SNRI
Duloxetine:
Role in OA?
- adjunctive Tx in patients with a partial response to first-line analgesics
- may be a preferred second-line med in patients with both neuropathic and MSK OA pain
Duloxetine:
Efficacy?
- demonstrated efficacy as add-on therapy when there has been less than optimal response to acetaminophen or oral NSAIDs
- reduction in pain occurs at about 4 weeks after initiation
Duloxetine:
Do not use with ?
potent CYP 1A2 inhibitors (fluvoxamine, cipro, ketoconazole) or MAOi
caution with other serotonergic drugs
Duloxetine:
Common AE?
GI with n/v, constipation
Duloxetine:
CI in ?
liver disease and severe renal impairment
Tramadol:
Dose
- 25 mg am, titrate dose in 25mg increments to reach maintenance of 50-100mg TID
- max dose of 200-300 mg/day
Tramadol:
MOA
analgesic with affinity for the mu-opioid receptor
Tramadol:
Role in OA?
- recommend as alternative first-line Tx of knee/hip pain in OA in patients who have failed Tylenol and topical NSAIDs, who are not appropriate candidates for oral NSAIDS and IA steroids
- tramadol can be safe add on therapy to partially effective acetaminophen or oral NSAID therapy (modestly effective)
- less data for monotherapy
Tramadol:
Efficacy ?
- demonstrated efficacy primarily as add on therapy when there has been less than optimal response to acetaminophen or oral NSAIDs
- reduction in pain occurs at about 4 weeks after initiation
Tramadol:
SE ?
- n/v, dizziness, constipation, headache, somnolence
* do not use if CrCl < 30
Risk factors for GI
- age > 65
- use of anticoagulants
- use of steroids
- history of PUD
- high dose of NSAID
- presence of H. pylori
What NSAIDs are the worse for Cardiac conditions?
-diclofenac and high dose celecoxib
What NSAIDs appear to be CV neutral?
- low dose naproxen (<750mg/day)
- ibuprofen (<1200mg/day)
- celecoxib (<200mg/day)
Any NSAID better than others for renal (AKI) ?
not likely
How can we manage GI risk with NSAIDs?
- PPI cotherapy
- H. pylori treatment
- Cox 2 inhibitors (celecoxib)
- misoprostol cotherapy
When do we monitor drug effect ?
Day 7, 14
When do we monitor pain relief ?
Day 3, 7, 14, 28
When do we monitor side effects ?
Day 3 and 7
When do we monitor HTN ?
measure within 1 week of NSAID therapy
When do we monitor renal function?
baseline, 1-2 weeks, then periodically (minimum annual) in those at risk
When do we monitor hepatotoxicity ?
baseline and annual LFT in those at risk