What physical tests should a 67-year-old female patient with chronic knee pain and knee effusion undergo during assessment?

Physical Examination Tests for Chronic Knee Pain with Effusion

For a 67-year-old female with chronic knee pain and knee effusion, perform a focused physical examination that includes assessment of joint effusion, range of motion measurement, gait evaluation, joint line tenderness, and crepitus detection, while recognizing that special meniscal tests have limited diagnostic value in this age group. 1, 2, 3

Essential Physical Examination Components

Joint Effusion Assessment

• Assess for the presence and severity of knee effusion, as this finding is routinely present in osteoarthritis patients and guides treatment decisions, particularly regarding aspiration or corticosteroid injection 1, 4, 2
• Document effusion severity, as synovitis/effusion changes are significantly related to the risk of frequent knee pain 5

Range of Motion Testing

• Measure passive arc of motion in both knees for comparison, documenting specific degrees of flexion and extension 1, 3
• The guideline case example documents measurement as "10° to 100° compared with 0° to 125° on the right side" to quantify functional limitation 1
• Limited range of motion is a characteristic feature of osteoarthritis 2

Gait Assessment

• Observe the patient's gait pattern and document whether an antalgic gait is present and whether assistive devices are used 1, 3
• This assessment helps determine functional impairment and need for assistive devices 4

Joint Line Tenderness

• Palpate for point tenderness along the medial and lateral joint lines, comparing tenderness between compartments 1, 2, 3
• Increased medial joint line tenderness compared to lateral suggests medial compartment involvement 1
• Joint line tenderness is a feature of osteoarthritis but has limited specificity 2, 3

Crepitus Detection

• Assess for crepitus in the patellofemoral compartment during range of motion testing, as this is a characteristic feature of osteoarthritis 2

Alignment Assessment

• Evaluate for varus or valgus alignment, as this can develop depending on the severity of osteoarthritis and indicates compartmental disease 2

Special Tests: Important Limitations

Meniscal Tests (McMurray's, Thessaly, Apley's)

• Be aware that special meniscal tests have very limited diagnostic value in this patient population 6, 3
• The Thessaly test has only 54% diagnostic accuracy when used by primary care clinicians and 59% by musculoskeletal clinicians 6
• McMurray's test has 54% diagnostic accuracy, and Apley's test has 53% diagnostic accuracy 6
• Meniscal tears are often incidental findings in older patients, with the majority of people over 70 years having asymptomatic meniscal tears 1, 4
• Special tests may cause increased pain in osteoarthritis patients who often have degenerative meniscal tears 2

Critical Differential Diagnosis Considerations

Referred Pain Assessment

• Clinically evaluate the hip if knee examination findings are unremarkable, as referred pain from hip pathology commonly presents as knee pain in this age group 1, 4, 5
• Consider lumbar spine pathology if knee findings do not explain symptoms, as lower back pathology can refer pain to the knee 1, 4, 5

Pain Pattern Localization

• Document whether pain is anterior (suggesting patellofemoral disorders), medial (suggesting medial compartment osteoarthritis or subchondral insufficiency fractures), or lateral (suggesting lateral compartment disease) 5
• Subchondral insufficiency fractures most commonly involve the medial femoral condyle in middle-aged to elderly females 1

Common Pitfalls to Avoid

• Do not rely on special meniscal tests to rule in or rule out pathology, as their sensitivity, specificity, and diagnostic accuracy are too low to be of routine clinical value as an alternative to imaging 6
• Do not assume a positive meniscal test indicates clinically significant pathology in patients over 45-55 years, as meniscal tears may be asymptomatic 1, 4
• Do not limit examination to the knee alone—always consider referred pain sources from hip and lumbar spine 1, 4, 5
• Age and past history of osteoarthritis are more significant predictors of meniscal pathology than physical examination tests 6