What is the difference between a bruise and a hematoma?
Understanding the fundamental distinction between a bruise (also called a contusion) and a hematoma is the first step to knowing when to be concerned. A bruise occurs when small veins and capillaries are broken, leaking a small amount of blood into the soft tissue just below the skin's surface. The result is the familiar flat, discolored patch that changes color as the body reabsorbs the blood. In contrast, a hematoma involves damage to larger blood vessels, causing a significant pooling or collection of blood in a specific area. This trapped blood often forms a clot, resulting in a raised, swollen lump that is typically more tender and painful than a standard bruise.
Recognizing a bruise: Symptoms and appearance
Bruises are a very common injury and typically heal on their own within a couple of weeks. Here's how to identify one:
- Appearance: Initially appears as a dark blue or purple patch of skin shortly after an impact. As it heals, the color changes to green, then yellowish-brown, before fading completely.
- Size: Generally appears as a flat, discolored area against the skin's surface.
- Pain: The area is usually tender or sore to the touch, but the pain is mild and improves over a few days.
- Sensation: The skin is not usually warm to the touch and lacks significant swelling.
Spotting a hematoma: Key signs and symptoms
A hematoma's symptoms are generally more pronounced and persistent than those of a simple bruise. It is important to look for these characteristics:
- Raised lump: A visible and palpable lump or swollen mass forms in the affected area as blood pools and clots. This lump can feel firm, rubbery, or spongy.
- Significant swelling and warmth: The area around the injury is noticeably swollen and may feel warm to the touch due to inflammation.
- Increased pain: Pain from a hematoma is often more severe and persistent than a bruise, especially when the area is pressed.
- Skin discoloration: Like a bruise, the skin discolors, but the patch is often larger and the color may be darker, sometimes appearing black.
- Prolonged healing time: Hematomas often take weeks or even months to fully resolve, depending on their size and location.
Different types of hematomas
Hematomas are classified based on their location, with varying levels of severity and visibility. For example, a subcutaneous hematoma is located just under the skin and is visible as a raised, painful lump. An intramuscular hematoma occurs deep within the muscle tissue, often causing pain and restricted movement. More serious types include subdural and epidural hematomas, which occur within the skull and can be life-threatening, causing symptoms like severe headaches, confusion, and seizures. A subungual hematoma is a collection of blood under a fingernail or toenail.
When to seek medical attention
While most bruises and minor hematomas resolve on their own, certain signs indicate the need for a professional medical evaluation. You should consult a doctor if:
- The lump or swelling continues to get larger or becomes more painful after the initial injury.
- The injury does not improve after two weeks.
- You suspect a hematoma in a sensitive area, such as the head, even if you don't feel a lump.
- You experience signs of infection, such as fever, red streaks, or pus draining from the area.
- The bruise or hematoma appears for no clear reason.
- You are on blood thinners and develop a significant hematoma.
Diagnosis and treatment
How doctors diagnose a hematoma
Diagnosing a superficial hematoma often begins with a physical examination, where a doctor inspects and palpates the affected area. However, to diagnose deeper or more severe internal hematomas, doctors use imaging tests:
- Computed Tomography (CT) Scan: Often used for hematomas in the head or abdomen to visualize the extent of the blood collection.
- Magnetic Resonance Imaging (MRI) Scan: Provides detailed images of soft tissue structures to identify the size and location of deeper hematomas.
- Ultrasound: Can be used to visualize superficial hematomas and assess their characteristics.
At-home care for superficial injuries
For mild bruises and superficial hematomas, the RICE method (Rest, Ice, Compression, Elevation) is the standard home treatment:
- Rest: Limit movement of the affected area to prevent further injury.
- Ice: Apply a cold pack wrapped in a cloth for 15–20 minutes at a time, several times a day for the first 48 hours to reduce swelling.
- Compression: Wrap the area with an elastic bandage, ensuring it's firm but not too tight.
- Elevation: Whenever possible, elevate the injured limb above heart level to reduce swelling.
For pain relief, acetaminophen (Tylenol) can be used, but avoid aspirin or ibuprofen unless directed by a doctor, as they can increase bleeding. According to the Cleveland Clinic, many hematomas are not serious and resolve on their own with proper care.
When surgical drainage is needed
In some cases, particularly for large, painful, or deep hematomas, medical intervention may be necessary. This can include:
- Drainage: A doctor may drain the hematoma using a needle and syringe to relieve pressure and pain.
- Surgery: If the hematoma is large, expands rapidly, or puts pressure on vital structures, surgical removal may be required.
Bruise vs. Hematoma: Comparison table
| Feature | Bruise (Contusion) | Hematoma |
|---|---|---|
| Appearance | Flat, discolored area on the skin | Raised, swollen lump or mass |
| Sensation | Mild tenderness | More significant pain, tenderness, and warmth |
| Cause | Damage to small capillaries | Damage to larger blood vessels, causing blood pooling |
| Healing Time | Typically 1–2 weeks | Weeks to months, depending on size and location |
| Severity | Generally minor and not serious | Can be minor or severe, depending on location |
| Treatment | Usually resolves on its own; RICE method for comfort | RICE method; sometimes requires medical drainage or surgery |
Conclusion
Distinguishing between a bruise and a hematoma is primarily about recognizing the nature of the swelling. A bruise is a flat discoloration from minor bleeding, while a hematoma is a raised, more painful lump caused by a larger collection of blood. While both result from trauma, the severity and potential complications differ significantly. For most superficial injuries, the RICE method is effective for both. However, if the swelling is severe, growing, or associated with other concerning symptoms, especially after a head injury, seeking professional medical attention is essential for proper diagnosis and treatment.
