Osteoarthritis

INTRODCUCTION

Osteoarthritis (OA) is a common, progressive disorder affecting primarily weightbearing diarthrodial joints, characterized by progressive deterioration and loss of articular cartilage, osteophyte formation, pain, limitation of motion, Deformity and disability

CLINICAL PRESENTATION

• Risk factors include increasing age, obesity, repetitive use through work or leisure activities, joint trauma, and genetic predisposition.
• Predominant symptom is deep, aching pain in affected joints. Pain accompanies joint activity and decreases with rest.
• Joints most commonly affected are the distal interphalangeal (DIP) and proximal interphalangeal (PIP) joints of the hand, first carpometacarpal joint, knees, hips, cervical and lumbar spine, and first metatarsophalangeal (MTP) joint of the toe.
• Limitation of motion, stiffness, crepitus, and deformities may occur. Patients with lower extremity involvement may report weakness or instability.
• Upon arising, joint stiffness typically lasts less than 30 minutes and resolves with motion.
• Presence of warm, red, and tender joints suggests inflammatory synovitis.
• Physical examination of affected joints reveals tenderness, crepitus, and possibly enlargement. Heberden and Bouchard nodes are bony enlargements (osteophytes) of the DIP and PIP joints, respectively

DIAGNOSIS

• Diagnosis is made through patient history, physician examination, radiologic findings, and laboratory testing.
• American College of Rheumatology (ACR) criteria for classification of OA of the hips, knees, and hands include presence of pain, bony changes on examination, normal erythrocyte sedimentation rate (ESR), and radiographs showing osteophytes or joint space narrowing.
• For hip OA, patient must have hip pain and two of the following:

(1) ESR less than 20 mm/h,

(2) radiographic femoral or acetabular osteophytes, and/or

(3) radiographic joint space narrowing.

• For knee OA, patient must have knee pain and radiographic osteophytes in addition to one or more of the following:

(1) age more than 50 years,

(2) morning stiffness lasting 30 minutes or less, (

3) crepitus on motion,

(4) bony enlargement,

(6) bony tenderness, and/or

(7) palpable joint warmth.

• ESR may be slightly elevated if inflammation is present. Rheumatoid factor is negative. Analysis of synovial fluid reveals high viscosity and mild leukocytosis

TREATMENT

Goals of Treatment:

(1) educate patient, family members, and caregivers;

(2) relieve pain and stiffness;

(3) maintain or improve joint mobility;

(4) limit functional impairment; and

(5) maintain or improve quality of life

• Acetaminophen is a preferred first-line treatment; it may be less effective than oral nonsteroidal anti-inflammatory drugs (NSAIDs) but has less risk of serious gastrointestinal (GI) and cardiovascular events.
• If a patient fails acetaminophen, nonselective NSAIDs or cyclooxygenase-2 (COX-2) selective inhibitors (e.g., celecoxib) are recommended. COX-2 inhibitors pose less risk for adverse GI events than nonselective NSAIDs, but this advantage may not be sustained beyond 6 months and is substantially reduced for patients taking aspirin. Proton pump inhibitors (PPIs) and misoprostol reduce adverse GI events in patients taking NSAIDs.
• For knee OA, topical NSAIDs are recommended if acetaminophen fails and are preferred over oral NSAIDs in patients older than 75 years. Topical NSAIDs provide similar pain relief with fewer adverse GI events than oral NSAIDs but may be associated with adverse events at the application site.
• Intra-articular (IA) corticosteroid injections are recommended for both hip and knee OA when analgesia with acetaminophen or NSAIDs is suboptimal. Injections can be given with concomitant oral analgesics for additional pain control. Do not administer injections more frequently than once every 3 months to minimize systemic adverse effects.