Pain or tenderness upon pressure on the crown or top of the head is known as scalp tenderness. Medically, this symptom often falls under the category of allodynia, where a stimulus that should not cause pain, such as a light touch, instead results in a painful response. The origins of this localized sensitivity are diverse, ranging from simple external irritations and surface-level skin issues to complex underlying neurological conditions. Understanding the distinct causes is the first step in addressing this discomfort and determining whether medical attention is necessary.
Understanding Scalp Tenderness
The most straightforward reasons for a painful response when the top of the head is pressed involve issues affecting the skin, hair follicles, and the immediate superficial tissue. Inflammation of the hair follicles, known as folliculitis, is a common culprit, causing small, tender, pus-filled bumps around the hair roots. These localized infections often cause sharp pain when the specific spot is touched.
Dermatological conditions also cause sensitivity, including seborrheic dermatitis (flaky, itchy patches) or contact dermatitis from allergic reactions to hair products. The associated inflammatory response makes the skin hypersensitive to mechanical pressure. External pressure from tight headgear, such as hats or helmets, or persistent tension from tightly pulled hairstyles can also irritate the scalp. This constant pulling on the hair shafts and follicles leads to inflammation and pain, known as traction-induced tenderness.
How Primary Headaches Cause Sensitivity
When scalp tenderness accompanies a headache, particularly a migraine, it is often a manifestation of cutaneous allodynia. This neurological phenomenon causes heightened sensitivity where everyday actions, such as brushing hair or resting the head on a pillow, are perceived as painful.
The mechanism behind allodynia is not local inflammation but rather a sensitization of the central nervous system. This sensitization begins with the activation of pain pathways during a migraine attack within the trigeminal nerve system.
If initial pain signals are not stopped promptly, the neurons in the brainstem and spinal cord become hyperexcitable, a state known as central sensitization. This heightened state causes normally non-painful stimuli to be misinterpreted as pain by the brain, leading to the tenderness felt on the scalp. Allodynia affects approximately 60% of people with migraine and may indicate a greater risk for the condition becoming chronic.
Specific Neuralgia and Referred Pain
Tenderness concentrated on the top of the head can stem from specific nerve irritation, known as neuralgia, or pain referred from musculoskeletal structures. Occipital neuralgia occurs when the occipital nerves, which run from the upper neck into the scalp, are compressed or inflamed. Irritation of these nerves sends shooting, electric-shock-like pain that originates at the back of the head and travels upward to the crown.
Occipital neuralgia pain can be triggered by simple movements like turning the head or lying down, causing the affected scalp area to become extremely tender. This nerve-related tenderness differs from headache-related allodynia because it follows the pathway of the irritated nerve. Chronic tension in the neck and shoulder muscles can also contribute to cervicogenic headaches. Muscle tightness refers pain forward, creating tender spots on the scalp, often involving compression of the greater occipital nerve.
Recognizing When to Consult a Doctor
While many causes of scalp tenderness are benign, certain associated symptoms necessitate immediate medical evaluation. Urgent attention is required for severe symptoms, especially those indicating a neurological emergency. Consult a doctor immediately if you experience:
- A sudden-onset, severe headache, often described as the “worst headache of your life” or a thunderclap headache.
- Pain accompanied by systemic signs, such as a high fever, stiff neck, confusion, or changes in alertness.
- Neurological symptoms, including sudden weakness, numbness on one side of the body, difficulty speaking, or changes in vision.
- A new headache or one that drastically changes in character, especially in an individual over the age of 50.
- Persistent, worsening pain that does not respond to common remedies or tenderness following a head injury.