Brush / Stroke Test (Swipe Test) Special Test
Orthopedic Physical Examination & Clinical Assessment Guide
What is it used for?
- Detecting Minimal Knee Effusion (swelling) that Ballottement might miss.
How to Perform
- Step 1: Stroke upwards on the medial side of the knee (to empty the fluid).
- Step 2: Stroke downwards on the lateral side of the knee.
Interpretation of Results
- Positive Test: A wave of fluid creates a bulge on the medial side. Graded from Trace to 3+.
Diagnostic Accuracy
- More sensitive than Ballottement for small amounts of fluid (4-8ml).
Clinical Context & Limitations
The Brush / Stroke Test (Swipe Test) should be considered as one component of a comprehensive musculoskeletal assessment. No single special test has perfect diagnostic accuracy; thus, clinical decision-making should integrate test results with patient-reported symptoms, mechanism of injury, functional impairment, and relevant imaging.
Clinicians should be aware of potential false-positive results in patients with pain sensitisation, muscle guarding, or poor relaxation. For the Knee region, combining the Brush / Stroke Test (Swipe Test) with complementary examination tests significantly improves overall diagnostic confidence.
References
- Magee, D. J. (2021). Orthopedic Physical Assessment.
