Aponeurosis

An aponeurosis is a type of flat, broad sheet of dense regular connective tissue that serves as a tendon-like structure to attach muscles to bones, other muscles, or fascia. Unlike a cord-like tendon, an aponeurosis spreads its force over a wide area and can blend with surrounding fascia. The tissue is rich in parallel collagen fibers and is relatively avascular.

In anatomy, several major aponeuroses are notable. The linea alba is a midline abdominal aponeurosis formed by the fusion of the anterior abdominal wall aponeuroses. The plantar aponeurosis (plantar fascia) supports the arch of the foot. The palmar aponeurosis anchors the palm and finger flexors. The galea aponeurotica (epicranial aponeurosis) links the frontal and occipital muscles of the scalp.

Functionally, aponeuroses transmit muscular force to bones or other tissues and provide a broad, flat anchoring surface. They also help distribute tension and can contribute to the mechanical integrity of body regions, such as the abdominal wall or the hand.

Clinically, injuries can include strain or rupture of an aponeurosis, and disease of the plantar aponeurosis (plantar fasciitis) is a common cause of heel pain. Treatment varies by location and severity, ranging from rest and physical therapy to surgical intervention in rare cases.