Lumbar Fat Herniation

From WikiMSK

Revision as of 08:11, 27 April 2021 by Jeremy (talk | contribs)

This article is a stub.
Lumbar Fat Herniation
Synonym Episacral lipoma, sacroiliac lipoma, back mouse, fibro-fatty nodule, fibrositis, subfascial fat herniation
Epidemiology present in 10โ€“58%
History Chronic low back pain
Examination Focal tenderness
Diagnosis Subcutaneous iliac crest nodule plus abolition of pain with local anaesthetic injection.
Tests Local anaesethetic injection
Treatment Local anaesthetic injections, steroid injections, excision.


Episacral lipomata are an uncommon cause of chronic low back pain with only infrequent mention in the literature. They occur over the posterior iliac crest as an ovoid, mobile, and subcutaneous small mass.[1]

Pathophysiology

There are two hypotheses regarding the pathophysiology. Some authors state that the condition is where deep fat herniates through the thoracolumbar fascia in a more superficial extramuscular, subcutaneous location. Other authors report that they are discrete lipomata or fibro-fatty nodules. The thoracolumbar fascia has fenestrations where cutaneous branches of the dorsal rami pass through, but it isn't clear how fat herniation can actually cause pain however.[2][1]

They are a discrete entity from inferior lumbar hernias. Lumbar hernias are where there is herniation of intra- or retro-peritoneal structures through the inferior lumbar triangle into the soft tissues of the low back.[1]

Epidemiology

There is a wide range of reported prevalence from 10โ€“58%, and may be bilateral. They are usually asymptomatic. They have a predilection for females.[1]

Clinical Features

The patient may report a painful subcutaneous mass in the lumbosacral region. The pain may radiate to to the buttock or thigh. Pain may radiate to the buttock or thigh [3, 4]. It may be acute or chronic in nature

Diagnosis

The diagnosis is supported by abolition of pain with infiltration of local anaesthetic.[2]

Treatment

Treatment options include local anaesthetic and/or steroid injections, and excision.[1]


References

  1. โ†‘ 1.0 1.1 1.2 1.3 1.4 Tiegs-Heiden et al.. Subfascial fat herniation: sonographic features of back mice. Skeletal radiology 2018. 47:137-140. PMID: 28914351. DOI.
  2. โ†‘ 2.0 2.1 Bogduk, Nikolai. Clinical and radiological anatomy of the lumbar spine. Chapter 15. Edinburgh: Elsevier/Churchill Livingstone, 2012.

Literature Review