A hematoma is a collection of blood that forms outside of a blood vessel. It occurs when an injury causes blood vessels to leak blood under the skin. Depending on the severity of the injury, a hematoma can be relatively small or very large.
What causes a hematoma?
Some common causes of hematomas include:
- Blood thinning medications – These prevent blood from clotting properly, allowing blood vessels to leak more.
- Injury – Any trauma that damages blood vessels can lead to bleeding and hematoma formation. Common culprits include falls, bumps, cuts, scrapes, and surgical procedures.
- Blood disorders – Conditions like hemophilia impair the blood’s ability to clot.
- Advanced age – Fragile blood vessels are more prone to leakage.
What does a hematoma feel like?
A new hematoma is often described as a soft, spongy swelling. It feels tender and painful to the touch. As the hematoma evolves over hours to days, it often becomes firmer and less compressible as blood coagulates into solid clots.
What are the stages of a hematoma?
A hematoma generally progresses through the following stages:
- Acute phase – The hematoma is newly formed and feels soft and compressible. The overlying skin may appear bright red as blood continues to leak into the area.
- Early subacute phase – Over the first 24-48 hours, the hematoma begins firming up and is less compressible as clots form. The skin color transitions to a bruised, purple appearance.
- Late subacute phase – From 2-5 days out, the hematoma is firmest as blood fully coagulates into solid clots. The bruise color shifts from purple to greenish-yellow.
- Chronic phase – After 5-7 days, the body starts reabsorbing the hematoma. It slowly softens and decreases in size over the next several weeks.
How long does a hematoma stay hard?
The duration a hematoma remains firm and hardened depends on its size and location:
- Small, superficial hematomas may only stay hardened for 2-5 days.
- Medium hematomas often remain firm for 1-2 weeks.
- Large, deep hematomas can stay hardened for 3-6 weeks before softening.
Factors affecting duration of hardness:
- Size – Larger hematomas have more coagulated blood and take longer to soften.
- Depth – Deeper hematomas are harder and persist longer.
- Location – Areas with poorer circulation tend to prolong hematoma duration.
- Bleeding disorders – Impaired clotting can delay hematoma solidification.
- Medications – Blood thinners hinder clot formation.
- Reinjury – Further trauma restarts the blood leakage and clotting process.
How is a hematoma diagnosed?
Diagnosing a hematoma involves:
- Medical history – Discussing risk factors, medications, and events surrounding the swelling.
- Physical exam – Inspecting and palpating the area to characterize the hematoma.
- Imaging tests – An ultrasound, CT scan, or MRI can confirm the presence and help determine the size of a hematoma.
What is the treatment for a hematoma?
Treatment options for a hematoma may include:
- Rest – Avoiding use of the affected area allows the hematoma time to heal.
- Ice – Applying cold packs can help minimize swelling and pain.
- Compression – Wrapping the area with an elastic bandage helps limit swelling expansion.
- Elevation – Keeping the affected limb elevated above heart level aids drainage.
- Pain medication – Over-the-counter drugs help relieve discomfort.
- Procedures – Severe or unresolved hematomas may need drainage, injection, or surgical repair.
Home care for a hematoma
To speed up recovery from a minor hematoma:
- Rest the injured area for the first 48 hours.
- Apply ice packs for 10-15 minutes several times per day.
- Use over-the-counter pain relievers as needed.
- Bandage with light compression using stretchy wraps or tape.
- Keep the affected limb elevated when possible.
- Avoid putting heat on the area for the first couple days.
- Gently massage the edges of the hematoma toward the center to aid healing.
- Monitor for worsening redness, pain, swelling, warmth or drainage.
When to see a doctor
Seek prompt medical care for:
- Very large or rapidly expanding hematomas
- Hematomas with severe pain or numbness
- Bleeding disorders or blood thinners
- Injuries causing significant deformity
- Hematomas affecting delicate areas like the eyes
- Signs of infection like fever, redness, warmth or pus
- Hematomas not improving after 2-3 weeks
Can a hematoma become infected?
Yes, there is a risk of the hematoma becoming infected, especially if the overlying skin was broken. Signs of an infected hematoma include:
- Increasing pain, swelling and redness
- Skin that is warm or hot to the touch
- Fever
- Red streaking around the site
- Pus or foul-smelling drainage
- Enlarged lymph nodes
An infected hematoma requires prompt medical treatment with antibiotics. The area may need to be drained and irrigated. Severe infections can become life-threatening.
Can a hematoma cause permanent damage?
In most cases, hematomas resolve without permanent problems. However, sometimes a severe hematoma can damage surrounding tissues and nerves, leading to:
- Significant scarring
- Skin discoloration
- Fluid accumulation (seroma)
- Infection
- Compartment syndrome – dangerously high pressure within an enclosed muscle space
- Contracture – permanent shortening or stiffening of a muscle
- Loss of normal muscle function
- Numbness or paralysis from nerve compression
Prompt medical care is vital for major hematomas to help prevent permanent damage. Physical therapy may be needed after to regain normal functioning.
Does a hematoma need to be drained?
Most minor hematomas will be reabsorbed by the body naturally over time. However, draining may be considered if the hematoma:
- Is very large
- Is placing pressure on vital structures like nerves or blood vessels
- Is causing severe pain or numbness
- Appears infected
- Is restricting joint mobility or muscle function
- Does not improve after several weeks
Potential drainage procedures include:
- Needle aspiration – inserting a needle to draw out the fluid
- Surgical incision – making a small cut to open and wash out the hematoma
- Placing a drain catheter – leaving a tube in place to allow continued drainage
How can you prevent a hematoma?
To help avoid a hematoma:
- Be careful when using sharp tools or objects
- Wear protective gear when engaging in sports or risky work
- Keep furniture corners padded and clear walkways of clutter
- Install handrails on stairs and grab bars in bathrooms
- Ask about alternative medications if taking blood thinners
- Get prompt treatment for conditions like hemophilia
- Don’t delay seeking care for injuries that break the skin
Conclusion
In summary, a hematoma usually remains hardened anywhere from 2 days to several weeks depending on its severity and location. Small, superficial ones tend to resolve quickest, while large, deep hematomas can stay firm for a number of weeks as the body gradually reabsorbs the coagulated blood. With proper home care and follow up, most hematomas will dissipate without issues. However, prompt medical attention is required if there are signs of infection or damage to vital structures from a severe hematoma.