Episacral Lipoma

Generally soft to the touch, an episacral lipoma is a lump of fatty tissue which appears on the lower back. Although lipomas are fairly common, they may require removal if the patient is experiencing pain due to the positioning of the episacral lipoma.

What is an episacral lipoma?

Lipomas are lumps of fatty tissue which can occur anywhere on the body, although they’re most common on the shoulders, arms, chest or back. Episacral lipomas are lumps of fatty tissue which appear on the lower back or around the sacroiliac joint.

In most cases, patients don’t notice any pain coming from a lipoma but episacral lipomas can sometimes cause discomfort due to their location. Generally, episacral lipomas feel quite soft to touch and they may appear to move under the skin when they are pressed.

Although episacral lipomas grow fairly slowly, they can reach quite a significant size. An episacral lipoma may start out as pea-sized, for example, but could grow to a few centimeters wide if it is not removed.

What are the symptoms of an episacral lipoma?

When patients first notice they have an episacral lipoma, it’s normally because they’ve felt a lump on their lower back. For many people, episacral lipomas will not cause any other symptoms, although unknown lumps should always be checked by a medical professional, regardless of whether the patient has any other symptoms.

In some cases, patients with an episacral lipoma may notice other symptoms occurring. These can include:

  • Pain or discomfort in the lower back
  • Restricted movement

Although the vast majority of lipomas are painless, some patients may experience lower back pain due to an episacral lipoma. If the pain worsens when the patient moves, they may find sitting or standing to be particularly painful and their movement may, therefore, be restricted. Similarly, if patients have on-going or chronic back pain, their movement may be limited over time.

For many patients, however, lipomas will not cause any noticeable symptoms. Whilst patients may be able to feel the fatty lump protruding from their back, they may not experience any discomfort as a result of the lipomas being present.

What causes an episacral lipoma?

When an episacral lipoma forms, it is believed that fatty tissue breaks through the overlying muscle and lays closer to the skin. Normally, this subcutaneous fat lies further below the surface of the skin and cannot, therefore, be felt by touching the skin. When an episacral lipoma forms, however, the fatty tissue effectively herniates through the collagen which lies beneath the skin.

It is unclear exactly why this happens. Whilst a breakdown in collagen or connective tissues may be responsible, other factors are believed to be relevant to the formation of episacral lipomas. These include:

  • Previous injuries
  • Genetics
  • Obesity

Patients who have suffered previous injuries or back pain may be more prone to episacral lipomas. Doctors are still unsure exactly why these types of injuries increase the likelihood of episacral lipomas developing, but damage to existing tissue may enable the fatty tissue to reach the skin more easily.

In addition to this, genetics appears to play a role in the development of episacral lipomas. Studies have shown that people are more likely to develop this type of lipoma if they have family members who have also experienced the condition.

A person’s weight may also have an impact on the presence of episacral lipomas. These types of lipomas are more common is people who are carrying excess weight, although it’s not known why this increases the rate at which episacral lipomas develop.

Although doctors are able to identify a range of factors which appear to influence the development of episacral lipomas, the exact cause of these lumps is still largely unknown.

Can an episacral lipoma be treated?

Although episacral lipomas can be treated, it is not always necessary to undertake any form of treatment at all. When patients first notice a lump or bump on their back, they should obtain medical advice. Whilst lipomas are benign, other types of lumps could be more dangerous so they should always be examined by a doctor.

Often, physicians are able to diagnose an episacral lipoma just by feeling the affected area. If they are in any doubt, however, imaging tests or biopsies may be carried out in order to determine whether the patient’s lump is an episacral lipoma and not something which requires more urgent treatment.

If a lipoma is confirmed and the patient isn’t experiencing any other symptoms, physicians may recommend that no further treatment is undertaken. Often, physicians will monitor the growth of an episacral lipoma but will not recommend treatment unless additional symptoms become apparent.

If patients are experiencing pain due to an episacral lipoma, treatment may be recommended. Physicians may recommend:

  • Injecting local anesthetic into the area, or
  • Removing the episacral lipoma

When the local anesthetic is injected into the area, it should provide temporary pain relief to the patient. Whilst local anesthetic does wear off fairly quickly, many patients with episacral lipomas have reported significant pain relief from just one injection.

Alternatively, a minor operation can be carried out so that the episacral lipoma can be removed. Providing the lipoma is not lying close to nerves, tendons or ligaments, this should be a fairly straightforward procedure. Once the lipoma has been removed, patients often find that their lower back pain has been considerably reduced.

How can an episacral lipoma be prevented?

As the exact cause of episacral lipomas is still unknown, it can be difficult to know how to prevent them. Many doctors recommend consuming a healthy diet and engaging in an appropriate amount of exercise, as this can help to reduce subcutaneous fat and maintain strength in the connective tissues under the skin. It is possible that this will reduce the likelihood of an episacral lipoma occurring but this is not guaranteed.

Many patients with episacral lipomas have experienced prior back injuries, so taking care to avoid damaging this area could also prevent these type of lipomas from developing. Whilst it may not always be possible to prevent an episacral lipoma, individuals may be able to reduce the likelihood of a lipoma developing if they undertake regular exercise and maintain a healthy lifestyle.