From Pergamon to Army Base Hospital No. 5: the history and significance of the galea aponeurotica in the evolution of neurosurgery.

The authors trace the etymology and historical significance of galea or epicranial aponeurosis. In ancient Greece, galea referred to a helmet worn by soldiers, typically made of animal hide or leather. Throughout antiquity, physicians referred to all soft tissue between the skin and the skull as panniculus, a standard established by Galen of Pergamon. A manual of surgery in the Middle Ages referred to the entire scalp as a "great panicle that is called pericranium." During the early Renaissance, Leonardo da Vinci famously and stylistically analogized the dissection of the cranium with the peeling of an onion. Not until 1724 would the tendinous sheath connecting the frontalis and occipitalis muscles be defined as "Galea tendinosa cranii." By 1741, the convention of referring to the galea as an aponeurosis was well established. Harvey Cushing's wartime experiences at Army Base Hospital No. 5 reinforced the surgical significance of the galea. Operative mortality was significantly diminished due to "closure of the wounds with buried sutures in the galea." This operative nuance was then passed from teacher to pupil and has now become one of the tenets of modern neurosurgical practice.