Ever Heard of Back Mice? (aka Episacral Lipoma)
Episacral lipoma (also called an episacroiliac lipoma or lumbar fascial fat herniation). These are small, tender, rubbery nodules of fat that push through a tiny tear in the connective tissue layer (fascia) of the lower back.
What is a Lipoma?
A lipoma is a benign (non-cancerous) collection of fatty tissue that develops beneath the skin. Lipomas are common and usually grow slowly over time. Many never cause symptoms, but those located over the sacrum (tailbone area) can become irritated due to prolonged sitting, pressure, or repeated friction. These are sometimes called “back mice”—->strangely so!
Pain is often caused by irritation of the surrounding soft tissues or small sensory nerves rather than the lipoma itself.
Tips to Reduce Pain and Irritation
Ice
Apply an ice pack for 10–15 minutes after activities that increase discomfort.
Always place a towel between the ice and your skin.
Voltaren (Diclofenac) Gel
May help decrease inflammation and soreness in the surrounding tissues.
Apply as directed on the package unless your healthcare provider has instructed otherwise.
Do not apply to broken or irritated skin.
Topical Desensitizing Creams
If the area is sensitive to touch, these products may help:
Aspercreme® with Lidocaine
Lidocaine 4% cream or patches
Biofreeze® (provides a cooling sensation for temporary relief)
Use only as directed and discontinue if skin irritation develops.
Protect the Area
Try to minimize repeated pressure or friction:
Avoid prolonged sitting when possible.
Change positions frequently.
Consider using a cushion if sitting aggravates symptoms.
Wear clothing that does not rub excessively over the area.
Massage
Gentle massage of the surrounding muscles may help reduce muscle tension.
Avoid deep or aggressive massage directly over the lipoma, as this may increase irritation.
Move Smarter
When bending, lifting, or standing:
Hip Hinge
Bend from your hips while keeping your back relatively neutral.
Let your hips do the work rather than rounding your lower back.
Avoid repeatedly bending and twisting through your lower back when lifting or transitioning from sitting to standing.
Gentle Movement
Staying active is usually beneficial.
Helpful activities may include:
Gentle walking
Easy yoga or stretching
Pelvic mobility exercises
Gentle hip stretching
Light core and hip strengthening (within comfort)
Movement should not significantly increase your symptoms.
When to Contact Your Healthcare Provider
Seek further evaluation if you notice:
Rapid enlargement of the lump
Increasing pain despite conservative care
Redness, warmth, or drainage
Numbness or weakness in the legs
Changes in bowel or bladder function
Unexplained weight loss or other concerning symptoms
Remember
Most sacral lipomas are benign and do not require surgery. The goal of treatment is to reduce irritation, protect the area from repeated stress, and keep you moving comfortably. If symptoms continue or worsen, your healthcare provider can discuss whether additional imaging or surgical removal is appropriate.Article content here.
Phil Rolfe, DPT
Owner, BodyLogic Physical Therapy – Weaverville, NC
Special interests include pain neuroscience education, orthopedic rehabilitation, dry needling, balance and fall prevention, and helping active adults remain independent through evidence-informed physical therapy.