Editing Scalp (section)

===Layers===
The scalp is usually described as having five layers, which can be remembered using the [[mnemonic]] 'SCALP':
* S: [[Skin]]. The skin of the scalp contains numerous [[hair follicle]]s and sebaceous glands.
* C: [[Connective tissue]]. A dense subcutaneous layer of [[fat]] and fibrous tissue that lies beneath the skin, containing the nerves and vessels of the scalp.
* A: [[galea aponeurotica|Aponeurosis]]. The epicranial aponeurosis or galea aponeurotica is a tough layer of dense fibrous tissue which anchors the above layers in place. It runs from the [[frontalis muscle]] anteriorly to the [[occipitalis]] posteriorly.
* L: [[Loose areolar connective tissue]]. This layer has a gel-like consistency, and allows the more superficial layers of the scalp to shift about in relation to the pericranium. It is constituted of more [[Matrix (biology)|matrix]] than fibers. It contains {{Clarify|text=random [[collagen I]] bundles, [[collagen III]]|date=February 2024}} and is rich in [[glycosaminoglycans]] (GAGs). In [[craniofacial surgery]] and [[neurosurgery]] this layer provides an easy plane of separation between the upper three layers and the pericranium. In [[scalping]] the scalp is also torn off through this layer. The layer is sometimes referred to as the "danger zone" because infectious agents can easily spread through it to [[emissary veins]] which drain into the [[skull|cranium]]. 
* P: Pericranium. This is the [[periosteum]] of the skull bones, a membrane that provides nutrition to the bone and the capacity for repair. During surgery it can be lifted from the bone to allow the removal of windows of bone ([[craniotomy]]).