Skin dimple Pretibial dimple 2019-05-27T13:33:38Z A groove or crease on the shins (pretibial, i.e., over the shin bone). Pretibial creases may be obvious at birth and may range from 3 cm to over 15 cm in length and lengthen as the limb grows. They appear as an elongated dimple because of the attachment of skin to underlying tissue (e.g., to the tibia). The dimple or crease grows in proportion to the growth of the leg.