The Homans sign is a technique used to check for thrombosis in the deep veins of the lower leg. The patient lies flat with the lower extremity in extension and the operator stands on the affected side, using the hand to passively dorsiflex the ankle. After dorsiflexion, the gastrocnemius and hallux valgus muscles will be passively pulled, which, if there is a thrombosis in the deep vein, will cause significant pain in the posterior calf during the passive pull. If the body is in a normal state and there is no deep vein thrombosis, the Homans sign is negative and there is no pain.