Expansion
SCALP
Mnemonic
SCALP, from superficial to deep:
- S - Skin
- C - dense Connective tissue
- A - epicranial Aponeurosis (galea)
- L - Loose areolar tissue
- P - Pericranium
Two consequences follow directly:
- The dense connective tissue holds vessel walls open, so scalp lacerations bleed profusely and do not constrict
- The loose areolar layer is the danger layer: it lets blood and pus spread freely, and its emissary veins drain to the intracranial dural sinuses, so infection can reach the skull. A haematoma here tracks to give panda eyes
The first three layers move as one unit, which is why the scalp can be avulsed intact.
Expansion
- S - Skin
- C - Connective tissue, dense and vascular
- A - Aponeurosis, the epicranial aponeurosis
- L - Loose areolar tissue, the danger layer
- P - Periosteum