Osteoarthritis of the Knee: Clinical Manifestations and Management

Primary Clinical Manifestations

Knee osteoarthritis is characterized by joint pain, stiffness, and functional limitations, with symptoms worsening over time and increasing with joint use, according to the American College of Rheumatology 1, 2
Pain is often localized to the affected compartment of the knee, commonly medial joint line tenderness, as reported by the European League Against Rheumatism 2
Morning stiffness typically lasts less than 30 minutes, as stated by the American College of Rheumatology 3
Difficulty with purposeful movement, especially weight-bearing activities, is a common symptom, according to the American Academy of Orthopaedic Surgeons 4
Decreased range of motion is a characteristic of the condition, as noted by the American Academy of Orthopaedic Surgeons 5
Joint line tenderness, particularly at the medial compartment, is a physical examination finding, as reported by the American Academy of Orthopaedic Surgeons 5
Joint effusion, or swelling, of varying severity is a common physical examination finding, according to the American Academy of Orthopaedic Surgeons 5
Decreased range of motion compared to the unaffected knee is a characteristic of the condition, as stated by the American Academy of Orthopaedic Surgeons 5
Antalgic gait pattern, or limping to avoid pain, is a common symptom, as reported by the American Academy of Orthopaedic Surgeons 5

Increasing age is the strongest risk factor, with prevalence rising significantly after age 55, as stated by the European League Against Rheumatism 2
Women are more commonly affected than men, representing 78% of diagnosed cases, according to the American Academy of Orthopaedic Surgeons 4
Obesity significantly increases risk and worsens symptoms, as reported by the American College of Rheumatology and the European League Against Rheumatism 1, 2
Prior knee trauma or surgery increases the risk of developing osteoarthritis, as stated by the European League Against Rheumatism 2
Genetic predisposition plays a significant role, with heritability estimates of 39-65%, as reported by the European League Against Rheumatism 2
Certain occupations requiring repetitive knee stress increase the risk of developing osteoarthritis, according to the American Academy of Orthopaedic Surgeons 5

The risk of disability from knee osteoarthritis equals that from cardiac disease and exceeds other medical disorders in the elderly, as stated by the European League Against Rheumatism 2
Approximately 10% of people over 55 years experience disabling knee symptoms, with a quarter being severely disabled, according to the European League Against Rheumatism 2

Focal loss of articular cartilage and marginal/central new bone formation are characteristic of the condition, as reported by the European League Against Rheumatism 2

Exercise programs, including strength training and aerobic exercise, are strongly recommended to reduce pain and improve function, as stated by the American College of Rheumatology and the American Academy of Orthopaedic Surgeons 1, 6
Weight loss is strongly recommended for overweight patients, according to the American College of Rheumatology and the American Academy of Orthopaedic Surgeons 1, 6
Pharmacological options, including acetaminophen, topical and oral NSAIDs, and intra-articular corticosteroid injections, are available for symptom management, as reported by the American College of Rheumatology 1
Joint replacement should be considered for refractory pain associated with disability and radiological deterioration, as stated by the European League Against Rheumatism 7
Self-management education programs can help reduce pain and increase coping skills, according to the American College of Rheumatology and the American Academy of Orthopaedic Surgeons 3, 6

Not considering mechanical factors, such as alignment and muscle weakness, is a common pitfall in assessment, as reported by the European League Against Rheumatism 2
Inadequate evaluation of other potential causes of knee pain is a common pitfall, according to the American Academy of Orthopaedic Surgeons 4