Specificity of the Femoral Slump Test for the Assessment of Experimentally Induced Anterior Knee Pain

Lai W-H, Shih Y-F, Lin P-L, Chen W-Y, Ma H-L. Specificity of the femoral slump test for the assessment of experimentally induced anterior knee pain. Arch Phys Med Rehabil 2012;93:2347-51. Objective: To assess the specificity of the femoral slump test (FST) when assessing experimentally induced anterior knee pain. Design: Cross-sectional, exploratory study. Setting: Research laboratory. Participants: Asymptomatic subjects (N=12; 6 men; 6 women) for the study. An experimental pain model was used to simulate anterior knee pain by injecting .25mL of hypertonic saline solution (5% NaCl) into the medial infrapatellar fat pad. Interventions: Not applicable. Main Outcome Measure: The changes in pain intensity and diameter after applying the structure differential maneuver (neck flexion/extension) during the FST were recorded and analyzed. Results: Results revealed that the structure differential maneuver of the FST did not alter the pain intensity or diameter in 9 (neck extension) and 10 (neck flexion) out of 12 subjects, which meant that the FST provided appropriate testing responses in 75% to 83% cases when the anterior knee pain did not originate in neural tissues. Conclusions: The FST had a specificity of more than .75 when detecting nerve mechanosensitivity problems of anterior knee pain.