The scalp is the area of the head where hair grows. It's composed of five layers: skin, connective tissue, aponeurosis (a fibrous sheet), loose connective tissue, and the periosteum (membrane covering the skull). The scalp is part of the epicranium, which refers to the structures covering the cranium.
The skin of the scalp contains numerous hair follicles, sebaceous glands, and sweat glands. The connective tissue layer provides insulation and contains blood vessels that nourish the scalp. The aponeurosis, also known as the galea aponeurotica, is a tough fibrous sheet that connects the frontalis and occipitalis muscles, allowing for scalp movement. The loose connective tissue layer is important for allowing the scalp to move freely over the skull, and it also provides a space for blood vessels and nerves to run through. The periosteum is the membrane that covers the bones of the skull and is responsible for their growth and repair.
The scalp is an important part of the body and can be affected by a variety of conditions, including:
- Dandruff: A common scalp condition caused by excessive skin shedding, often due to a fungus called Malassezia globosa.
- Scalp yeast infection: A fungal infection caused by Candida, causing itchy, flaky rash.
- Ringworm: A fungal infection that causes itchy, scaly, bald patches on the scalp.
- Hair loss: Can be caused by various factors, including genetics, hormonal changes, and medical conditions.
The scalp is also a common area for administering medications and treatments, such as:
- Scalp cooling: A method to reduce hair loss during chemotherapy.
- Scalp massages: May help with hair growth and relaxation.
- Butterfly needle insertion: Used for drawing blood or administering IV therapy.
