Hard Lump Under Incision After Surgery: Causes, Symptoms, Diagnosis, Treatment

After surgery, perhaps not immediately, but in the weeks thereafter, it’s possible to develop what feels like a hard lump beneath your rehabilitating incision scar. When tissue is excised at the site of incision, a postsurgical seroma can emerge. Here we’ll get into the particularities and traits of these lumps—why they form, what the symptoms are, how they are diagnosed, and treatment prospects.

What Is a Postsurgical Seroma?

A postsurgical seroma is a chamber of fluid that develops underneath a surgical incision. The pocket is full of clear or pale yellow serous fluid, and as it swells on the skin’s surface, it will resemble a large cystic lump.

Serous Fluid

Also known as serosal fluid, it has the hallmarks of a transparent serum. Serous fluid is present throughout the body and labors as a lubricant betwixt the outer membranes of the internal organs.

Serous glands secrete this fluid which is comprised mostly of water and proteins. This fluid exactly what fills up inside a blister.

What Causes a Postsurgical Seroma to Form?

In the case of seromas, they develop most frequently after a truly extensive, substantial operative procedure, where the tissue becomes heavily disrupted and harmed. However, minor incisions can also bear a seroma in the healing process too, it’s rather exceptional though.

After performing surgery, surgeons often place various tubes at the incision site to drain excess fluid in a preventative effort to reduce the likelihood of seromas and other complications. As this process simply reduces the chances of seroma development, it’s hardly foolproof and there’s no completely effective method of circumventing the threat of a postsurgical seroma.

While a seroma may arise after virtually any kind of surgical incision, they’re more likely to occur post the following procedures:

  • Liposuction (lipo)
  • Mastectomy
  • Breast augmentation (this includes implants and reduction)
  • Tummy tuck (abdominoplasty)
  • Plastic surgery (cosmetic and reconstructive)
  • Herniorrhaphy, hernioplasty (hernia repair)

The above procedures involve high amounts of disruption to the surrounding tissues, thus increasing the possibility of a seroma.

What Are the Symptoms of a Postsurgical Seroma?

Seromas are characterized by a lump resembling the traits of a cyst, and they can feel cushy and liquidy. The skin will swell at the location of the seroma and usually develop after a week to ten days.

Mild soreness and tenderness might accompany the seroma’s presence.

Not to Be Confused With…

Seromas can look and feel like a few other kinds of conditions:


A pocket resembling a serous fluid-filled sac, but actually containing an anomalous collection of lymphatic cells.


Similar to a seroma, but a hematoma is instead full of blood. Left untreated, hematomas can become infected and lead to hideous scarring.


An abscess is full of pus, rather than blood or serous fluid. Pus, which contains germs and dead tissue mixed with white blood cells, is a sign of infection and needs to be managed with a course of antibiotics, or by drainage.

It should be noted that a normal seroma that becomes infected can morph into an infectious abscess.

How is a Postsurgical Seroma Diagnosed and Treated?

Your doctor or surgeon will perform a general examination to inspect the seroma. If a diagnosis cannot be reached, an imaging scan may be performed to determine the contents of the lump beneath your incision.

After confirmation, there are several courses of action your physician may take if it doesn’t appear the seroma will heal on its own.

Of course, if your seroma has become infected, you will undoubtedly be prescribed antibiotics to fight the infection. Following that, a fine needle aspiration procedure will be the first step in drawing out the fluid, this process may need to be performed a number of times.

If this aspiration fails, a semipermanent drainage tube may be fitted and placed for fluid removal.

Another procedure for seroma treatment is called sclerosis, which injects medicine (or an antibiotic) directly into the seroma and is left for up to an hour to work its magic. The meds are then drained from the site, which encourages the wound to close up.

The final option involves going under the knife once again to surgically remove the lump.

Should your doctor opt out of treating your seroma, as it appears normal in nature, OTC pain medications can be ingested to deal with the discomfort and/or inflammation.

Proactive Seroma Management and Care

After you’ve undergone surgery, a tightly wound bandage should be kept on the site. The area should be properly dressed and kept clean to prevent bacterial complications. Such a wrap will also aid in the prevention of fluid collection and unnecessary skin stretching. Pressure garments are often prescribed as well.

Following an operation, it’s absolutely imperative to carefully adhere to your postop instructions. Only exert effort and movement as advised and take care of your incision as per your doctor’s specific guidelines.

Monitor your condition with a keen eye and look out for any signs of infection—reddish skin, abnormal swelling, purulent discharge or leakage, et cetera.

Report to your doctor immediately if the incision tears apart and starts bleeding or oozing pus; if you spike a high fever; or you become tachycardic.



Article References:

  1. https://www.healthline.com/health/seroma
  2. https://fac.ksu.edu.sa/sites/default/files/15-_serous.pdf
  3. https://www.medicalnewstoday.com/articles/312875.php
  4. https://www.drugs.com/cg/seroma.html