Modified Stroke Test
ICF category	Measurement of impairment of body structure, knee joint
Description	The amount of fluid in the knee joint measured by visual inspection by clinician
Measurement method	A stroke test is performed with the patient in supine and with the knee in full extension and relaxed. Starting at the medial joint line the examiner strokes upward 2 or 3 times toward the suprapatellar pouch in an attempt to move effusion from the knee. The examiner then strokes downward on the distal lateral thigh just superior to the suprapatellar pouch toward the lateral joint line. A wave of fluid may be observed within seconds on the medial side of the knee.6,95,155
Nature of variable	Ordinal
Units of measurement	Grading: Zero = no wave produced with downward stroke Trace = small wave of fluid on the medial side of the knee 1+ = Larger bulge of fluid on the medial side of the knee 2+ = Effusion completely fills the medial knee sulcus with downward stroke or returns to the medial side of the knee without downward stroke 3+ = Inability to move the effusion out of the medial aspect of the knee
Measurement properties	The modified stroke test has a Kappa value of 0.61. 155 72% of testing pairs had perfect agreement. 8% had a disagreement of 2 grades.
Instrument variations	Other effusion tests can be used to assess knee effusion. 27,76 In addition to visual inspection, knee effusion can be measured using a tape measure or perometer (an optoelectric device designed to measure limb volume) for knee circumference.98,160