Osteoarthritis

Pathogenesis, Etiology, and Incidence

Degenerative changes that occur in cartilage (a metabolically dynamic tissue) and associated bone

Characterized by increased destruction and subsequent proliferation of cartilage and bone; regenerated articular surfaces do not possess the same qualities and architecture as the original joint

Joints Commonly Affected

(3)

Distal Interphalgeal joint (DIP)

Hips

Knees

Clinical Manifestation/Presentation of OA

(11)

Joint Pain

Pain worse with activity

AM stiffness is brief (< 1hour)

Crepitus-creeking/crackling of joints

Inflammation in more advanced disea (pain at rest)

Asymmetric invovlement

Muscle Atrophy

No Systemic Symptoms

Instability of Weight Bearing Joints

Herberden's Nodes-cartilage covered at end of fingers

Bouchard's Nodes-enlargement of knuckles

Goals/Desired Outcomes of Therapy

(3)

Relief of pain and discomfort

Maintain function and strength of joint

Prevent deformities and progressive changes

Treatment of OA

Step-wise approach

1.  NON-drug therapy

2.  APAP or topical therapy

3.  NSAIDs

4.  Opiod analgesic

5.  Surgery

NON-Drug Approaches

(8)

Psychological Support

Education

Rest

Physical Activity/Exercise

Physical Therapy

OT

Weight Loss

Heat/Ice

Treatment of OA

STEP 2

Acetaminophen (Tylenol)

Dose:  650 mg QID or 1000 mg TID

Maximum Dose per Day:  3-4 g per day

Patients at Risk of Hepatoxicity:  Heavy alcohol intake, pre-existing liver disea, Monitor AST/ALT annually

Treatment of OA

STEP 2

Topical Therapy

Menthol/Camphor/Oil of Wintergreen

Topical Counter Irritant

Apply Sparingly

Use multiple times per day TID-QID

Avoid Contact with Eyes

SalonPAs Arthritis Pain Patch

10% methyl salicylate and 3% menthol

apply 8-12 hours (NOT more than 3 consecutive days)

Treatment of OA

STEP 2

Capsaicin Cream (Zostrix and Zostrix HP)

Diclofenac Topical Gel 1% (Voltaren Gel)

Start with lower strength

UseL  must used regularly TID-QID for optimal results

Wait 2-4 weeks to evaluate effect

Educate patient about proper application procedures

Applied directly to affected joint 4 times daily

Maximum of 16 grams applied to any one joint per day

Not recommended in combination with NSAIDs therapy

Treatment of OA

STEP 2

Diclofenac Topical Solution 1.5% (Pennsaid)

Lidoderm Patch 5% (Lidocaine)

DMSO vehicle

40 drops applied to each affected knee four times daily

Apply 10 drops at a time (spead evenly around entire knee)

Allo Solution to dry entirely before covering with clothing

Wash Hands Thoroughly

Trimmed to accomodate join

Cost when used long term

Treatment of OA

STEP 2

Glucosamine/Chondroitin

Dose:  500 mg TID (slow onset ~ 4 weeks)

Mixed Results about effectiveness

Treatment of OA

STEP 3

NSAIDs

If pt does NOT respond; switch to alternative NSAIDs

Selection based on cost, SEs, dosing convenience, other medical conditions, other medications, risk of bleeding, risk of PUD

Analgesic dose vs. Anti-inflammatory dose

Major ADR for which to monitor:  GI upset, GI ulcer, Bleeding, Renal Dysfunction, Effects on BP

1-2 week trial for pain and 2-4 week trial if inflammation exists

Patients at greatest risk for ADRS from NSAIDs and ASA

(6)

Elderly

pts with h/o GI bleed

pts with h/o PUD

pts on anticoagulant therapy

pts on glucocorticoids

pts with CHF, HTN, renal dysfunction, and dehydration are at increased risk of nephrotoxicity

Monitoring Elderly on NSAIDs

(5)

BP after adding NSAIDs

Sx of edema or weight gain

BUN/Cr every 3 months

Hgb/Hct every 6-12 months

Signs of dehydration

Treatment of OA

STEP 4

Intra-actricular corticosteroid injections

only used for isolated joints

no more often than every 4-6 months

Treatment of OA

STEP 4

Opioid Analgesics/Tramadol

Used PRN for breakthrough pan

Often used at bedtime to help pain sleep

Watch total dose of APAP very closely

Treatment of OA

Hyaluronate Injections

(Synvisc, Euflexxa, Hyalgan, Orthovisc, Supartz)

Injected once weekly x 3-5 weeks into joint

Maximum benefit in 8-12 weeks

Treatment of OA

STEP 5

Joint Resurfacing or Replacement Surgery

Relieves pain

Restores function to joint

Monitoring Parameters for Patients with OA

(10)

Pain (pain at rest)

Joint stability and function

Risk of fall

ROM

X-rays

Degree of Disability

Weight

ADRs from Medications

Adherence with Non-drug measures

QOL issues