How can you tell if a bruise is serious?

September 26, 2025 •

4 min read

According to the Cleveland Clinic, most hematomas, which are collections of blood outside of blood vessels, are not serious. However, determining how can you tell if a bruise is serious is crucial, as some indicators suggest a more significant injury or underlying health issue that requires professional medical attention.

Quick Summary

Assessing the severity of a bruise involves checking for signs like excessive swelling, a hard lump (hematoma), intense pain, numbness, or bruising accompanied by unexplained bleeding. Any bruise that doesn't improve within two weeks, appears without injury, or hinders movement warrants a medical consultation, as it may signal a deeper problem or an underlying condition.

Key Points

Persistent Pain: A bruise with severe or increasing pain that lasts more than three days is a red flag for a more significant injury, such as a severe sprain or fracture.
Visible Lumps (Hematoma): The formation of a firm, painful lump under the skin, known as a hematoma, indicates a deeper blood collection that might require medical drainage.
Unexplained Bruising: Frequent, large, or spontaneous bruising on the torso, back, or face, without a clear cause, can be a sign of an underlying medical issue, especially if you are not taking blood-thinning medication.
Impaired Movement: If a bruise near a joint significantly limits your ability to move the joint, it may suggest a serious injury like a bone bruise or joint bleeding (hemarthrosis).
Slow Healing: A bruise that does not begin to improve after two weeks or hasn't fully healed after a month should be evaluated by a doctor to rule out underlying medical conditions affecting clotting or healing.
Numbness or Weakness: A bruise accompanied by numbness, tingling, or weakness in the limb could signal nerve compression from severe swelling.

When a Bruise Goes Beyond a Simple Bump

Bruises, or contusions, are common occurrences resulting from minor injuries that cause small blood vessels to break beneath the skin. They typically heal on their own, changing colors from reddish-purple to greenish-yellow as the body reabsorbs the blood. However, certain symptoms should not be ignored, as they can indicate a more serious injury, such as a deep muscle bruise, bone bruise, or a condition affecting your body's clotting ability.

Key Warning Signs of a Serious Bruise

It is important to differentiate a normal bruise from one that may require medical attention. Look for these specific warning signs:

Extreme Pain and Swelling: A bruise accompanied by severe, rapidly worsening pain and significant swelling could indicate a hematoma or compartment syndrome, a dangerous condition caused by pressure buildup.
A Hard Lump: The formation of a hard, rubbery lump over the bruise is a sign of a hematoma, a deeper collection of blood that may need to be drained.
Bruise Near a Joint: A bruise around a joint, especially if it causes stiffness or an inability to move the joint, could point to a bone bruise or hemarthrosis (bleeding into the joint).
Delayed Healing: Most bruises heal within two to four weeks. A bruise that does not show signs of improvement after two weeks or has not healed completely after three to four weeks should be evaluated by a healthcare professional.
Numbness or Weakness: Numbness, tingling, or weakness in the limb with the bruise can be a red flag for nerve compression due to swelling.
Unexplained Bruising: Frequent, large, or painful bruises that appear without any clear cause, or in unusual locations like the back or torso, can be a symptom of an underlying medical condition.
Bruising on Blood Thinners: While increased bruising is common for those on anticoagulant medications, any new or concerning bruising should be discussed with a doctor, as the dosage may need adjustment.

Distinguishing Different Types of Bruises


Feature	Common Bruise	Hematoma	Bone Bruise	Compartment Syndrome
Appearance	Flat discoloration; changes color over time.	Raised, lumpy, spongy feeling; may be large and dark.	Often no visible bruise; deep, persistent pain.	Swelling is disproportionate to injury; skin may be shiny.
Pain Level	Mild to moderate tenderness.	Can cause significant pain, especially with size.	Deep, throbbing pain that is more severe and longer lasting.	Extreme, severe pain that doesn't subside.
Swelling	Mild swelling initially.	Notable swelling due to pooled blood.	Significant swelling around the bone or joint.	Severe, tense swelling; may feel hard to the touch.
Sensation	Tender to the touch.	Tender, firm, and painful.	Deep tenderness and stiffness.	Numbness, tingling, or intense pressure.
Healing Time	2–4 weeks.	Can take several weeks to months to resolve.	Can take several weeks to months to heal completely.	Medical emergency requiring immediate treatment.

When to Seek Immediate Medical Attention

While most bruises are not emergencies, certain symptoms warrant an immediate visit to the emergency room or urgent care. These include:

Signs of a head injury, such as a new bruise on the head or neck accompanied by a headache, dizziness, nausea, or confusion.
Vision changes or inability to move an eye if the bruise is near the eye.
A large, painful bruise on the abdomen or trunk that could indicate internal organ issues.
Symptoms of shock, such as pale, clammy skin, rapid breathing, or loss of consciousness.
Any bruise that inhibits your ability to move or walk normally.

What Your Doctor Will Do

If you see a doctor for a concerning bruise, they will likely perform a physical examination to assess the area and may ask questions about the injury's cause and any other symptoms. To rule out underlying issues, they might recommend tests such as blood work to check for clotting disorders or vitamin deficiencies, or imaging like an X-ray or MRI to check for fractures or a bone bruise. Your doctor can then provide a diagnosis and recommend the appropriate course of treatment.

Conclusion: Trust Your Gut and Seek Guidance

Bruises are a normal part of life, but knowing the difference between a minor injury and a potentially serious one is vital for your health. By paying close attention to signs like excessive swelling, severe pain, or a bruise that doesn't heal, you can determine if medical attention is necessary. Always trust your instincts, especially if a bruise seems disproportionate to the injury or is accompanied by other worrying symptoms. When in doubt, consulting a healthcare professional is always the safest option to ensure a proper diagnosis and prevent potential complications. For more information on health conditions, visit a trusted medical resource like the Mayo Clinic.

Frequently Asked Questions

A bruise is a superficial area of skin discoloration where small blood vessels have leaked. A hematoma is a larger, deeper collection of pooled blood that forms a hard, palpable lump beneath the skin and may cause more significant pain and swelling.

Most simple bruises resolve on their own within two to four weeks. During this time, they will typically change color from a purplish-blue to greenish-yellow before fading completely.

Yes, some medications, especially blood thinners like aspirin, warfarin, or certain antidepressants, can increase your risk of bruising. If you notice unusual or excessive bruising after starting a new medication, contact your doctor.

A bruise that does not progress through the typical color changes (red to purple to green to yellow) may be a sign that the body is not properly breaking down and reabsorbing the pooled blood. A bruise that lingers for over a month should be medically evaluated.

A bruise on the head or neck can be serious if accompanied by symptoms such as a severe headache, nausea, dizziness, vision problems, or confusion. These could indicate an internal hematoma and require immediate emergency care.

Yes, a bone bruise, for instance, may not cause a large visible mark on the skin but can result in deep, throbbing pain, significant swelling, and stiffness. These can take much longer to heal than a typical bruise.

Compartment syndrome is a dangerous and life-threatening condition where swelling from a deep bruise or other injury causes extreme pressure in a confined space, cutting off blood and oxygen to the nerves and muscles. It is an emergency that requires immediate surgery.