Muscle layer of panniculus adiposus

The muscle layer of panniculus adiposus is a thin layer of striated skeletal muscle found within or just deep to the subcutaneous fat (panniculus adiposus) in many mammals. In humans, the panniculus carnosus is largely vestigial and persists only in a few locations:

• Platysma in the neck

• Dartos muscle in the scrotum

• Palmaris brevis in the hand

In other mammals (e.g., rodents, horses), the panniculus carnosus is a well-developed, continuous sheet of muscle that allows the animal to twitch its skin — for example, to shake off insects. In humans, this muscle layer has been almost entirely replaced by fibrous connective tissue within the superficial fascia.