Hypotonia Floppy infant Hypotonia early Infantile muscular hypotonia Hypotonia, early Decreased muscle tone in infant HP:0010572 HP:0002449 Floppiness/hypotonia is defined as reduced resistance to passive movement of joints. Physical examination of floppy/hypotonic infants shows head lag, lack of shoulder and elbow muscle contraction on traction response, inability to tighten the shoulder girdle muscles (or slipping through) when held under the axillae, scarf sign (when the arm is pulled to the opposite side, the arm wraps around the neck with the elbow crossing midline), hyperdorsiflexion of the feet, easy apposition of the thumb against the forearm, feet touching the cheek with ease and without discomfort, frog leg position, and inverted U sign on ventral suspension (head, arms, and legs hanging down without elbow or knee flexion and the trunk rounded in a dome shape). UMLS:C1860834 Infantile hypotonia HP:0002523 HP:0008947 Hypotonia in infancy This term should not be used for new annotations. Instead, state the type of onset of hypotonia more exactly.