<unk>  occurs when the upper part of the rectus abdominis muscle is intact but the lower part is weak. When the patient is asked to raise his head as he lies supine on bed, the upper part of the muscle contracts disproportionately more than the lower portion, pulling the umbilicus toward the head.
Beevor's sign
Lockwood's sign
Litten's sign 
Litten's sign
Dance's sign
Adson's sign
Darier's sign
Hegar's sign