Finding an unexpected lump or knot on the head can instantly trigger concern. While the presence of a mass on the scalp or skull is common, most are harmless. Knowing the difference between a minor bump and one that requires medical evaluation is important.
Understanding Benign Knots on the Scalp
The majority of knots found on the head are benign, originating from the skin, soft tissues, or immune responses. One frequent cause is a trauma-related bump, known medically as a scalp hematoma or a “goose egg.” This lump is a localized collection of blood beneath the scalp layers following an injury. It typically resolves on its own within a few days as the body reabsorbs the pooled blood.
Other common, non-traumatic masses include various types of cysts and fatty growths. Pilar cysts, also called trichilemmal cysts, are the most prevalent type of cyst found on the scalp, often inherited and developing from the outer root sheath of a hair follicle. These are usually firm, smooth, dome-shaped lumps filled with keratin. They grow slowly and are typically painless unless they become irritated or rupture.
Another type of soft tissue mass is a lipoma, which is a tumor composed of fatty tissue situated just beneath the skin. Lipomas are characteristically soft or rubbery to the touch and movable when gently prodded, distinguishing them from firmer growths. These masses are harmless, slow-growing, and do not require removal unless they cause discomfort or cosmetic concern.
Lumps at the base of the skull, particularly near the neck, are often swollen lymph nodes. The occipital lymph nodes filter fluid from the scalp and nearby areas, swelling in response to an infection such as ringworm, folliculitis, or a viral illness. A lymph node swollen due to infection is typically soft, tender to the touch, and movable under the skin. Once the underlying infection clears, the lymph node should decrease in size, often returning to normal within a couple of weeks.
Signs That Warrant Immediate Medical Attention
Certain characteristics and accompanying symptoms act as specific warnings that necessitate a prompt medical evaluation. A lump that is fixed to the underlying tissue, feeling hard, dense, and immovable, is a concerning sign that should be assessed by a healthcare professional.
Rapid growth or a sudden, unexplained appearance of a lump without preceding injury is another red flag. Benign masses are known for their slow, gradual development. Any mass that rapidly increases in size should be professionally evaluated to determine its nature.
The presence of associated systemic symptoms alongside a head lump significantly increases the need for medical attention. These symptoms include unexplained weight loss, persistent fever, or drenching night sweats, which can be indicators of an underlying systemic illness. Furthermore, any lump that shows specific signs of acute infection, such as increasing redness, warmth, streaks radiating from the site, or a discharge of pus, requires immediate medical intervention.
Any new lump accompanied by neurological symptoms demands urgent care. This includes persistent, severe headaches, unexplained vision changes, confusion, or the onset of seizures. The combination of a mass and these neurological signs points to a possible issue within the skull that requires rapid diagnostic imaging.
How Doctors Diagnose and Treat Head Lumps
The evaluation of a head lump begins with a thorough physical examination and a detailed patient history. The doctor assesses the lump’s texture, size, mobility, and tenderness. The medical history focuses on when the mass first appeared, how quickly it has grown, and any symptoms or recent injuries that may be related to its formation. This initial assessment often allows the physician to form a likely diagnosis, such as a pilar cyst or a swollen lymph node.
If a lump is suspected to involve the underlying bone or deeper tissues, or if the diagnosis is uncertain, imaging studies are often utilized. Ultrasound is a common initial screening tool, providing a clear picture of the mass’s contents, such as whether it is solid, fluid-filled, or composed of fat. For suspected trauma, bony involvement, or deeper masses, a Computed Tomography (CT) scan or Magnetic Resonance Imaging (MRI) provides more detailed anatomical information.
In cases where malignancy is a possibility, or if the mass has concerning features, a biopsy is performed to obtain a tissue sample for laboratory analysis. This procedure determines the exact cell type and whether the growth is benign or malignant. The treatment plan is then tailored to the confirmed diagnosis.
Management for benign masses often involves watchful waiting, as many cysts and lipomas do not cause problems and stop growing on their own. For those that become infected, antibiotics may be prescribed, and cysts may be drained or surgically removed if they are painful, large, or cosmetically bothersome. If the mass is determined to be a more complex growth, the patient may be referred to a specialist, such as a dermatologist, head and neck surgeon, or neurosurgeon.