QS Study

The soft tissue covering the cranial vault is called the scalp. It is made up of the deep inner layer, the dermis, and the superficial layer, the epidermis.

Layers of the scalp: (Outer to Inner) It is made up of five layers –

  1. Skin – contains numerous hair follicles and sebaceous glands.
  2. Superficial fascia – connects the skin to the epicranial aponeurosis.
  3. Epicranial aponeurosis with the occipitofrontalis muscle – a thin, tendon-like structure that connects the occipitalis and frontalis muscles.
  4. Loose areolar tissue – a thin connective tissue layer that separates the periosteum of the skull from the epicranial aponeurosis.
  5. Pericranium – the outer layer of the skull bones.

Functional significance:

(a) Due to the abundance of sebaceous glands, the scalp is a common site for sebaceous cysts.

(b) The wound of the scalp bleeds profusely because the vessels are prevented from retracting by the fibrous fascia.

(c) The inflammations in this layer cause little swelling but much pain.

(d) It is known as the dangerous area of the scalp.

Scalp - Blood and nerve Supply 1

Fig: Scalp – Blood and Nerve Supply

Blood Supply

(A) Infront of the auricle, It is supplied from before backward by the:

  • Supratrochlear artery.
  • Superorbital artery.
  • Superficial temporal arteries.

(B) Behind the auricle, the scalp is supplied from before backward by the –

  • Posterior auricular artery.
  • Occipital arteries by of external carotid artery.

Venous Drainage:

  • The supratrochlear veins.
  • The supraorbital veins.
  • The superficial temporal vein.
  • The posterior auricular vein.
  • The occipital vein.
  • The vein of the scalp freely anastomoses with one another.

Nerve supply of the scalp

Sensory supply:

  1. The supratrochlear nerve.
  2. The supraorbital nerve.
  3. The zygomaticotemporal nerve.
  4. The auriculotemporal nerve.
  5. The lesser occipital nerve.
  6. The greater occipital nerve.

Motor supply:

  1. Temporal branch of facial nerve.
  2. Posterior auricular branch of fascial nerve.
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