1981 Tong – Pannicular sacroiliac hernia, report of 50 cases

This is a Chinese article (published in 1981), from a surgery journal. They report 50 cases of pannicular sacroiliac hernia (also named “back mice”). 

Notes on the article: 

pannicular sacroiliac hernia

[Pannicular sacroiliac hernia: Report of 50 cases]

Tong W.T.

Chinese journal of surgery (Zhonghua wai ke za zhi)

 1981 (4) p. 231 ISSN: 0529-5815.

Article written in Chinese.

Surgery Department.  Xuanwu Hospital. Pekin

This is a small report about 50 patients that underwent surgical excision of the fatty hernias (also named pannicular sacroiliac hernia or “back mice”) with 90% of good outcomes. Their technique included enlarging of the fascial defect.

It doesn’t give any references about other studies.

The authors start commenting that the hernia from the sacral fascia or pannicular sacroiliac hernia is a COMMON cause of low back and leg pain that usually is WRONGLY diagnosed as sciatica or other pains.

 They operated the fatty nodules with excision and fascial opening repair.

There was pain relief after surgery and they had good outcomes.


-9 from the 50 cases were bilateral cases

-40 women and 10 men

-age between 19 and 66

-40 cases had pain for more than one year

About symptoms:

-Low back pain started mainly with flexion or without any apparent reason.

-Low back pain got worse coughing, turning, with flexion or defecation.

-Pain could affect the gluteal region, the thigh or the leg.

-The low back pain could be very sharp with patient obligated to rest in bed and take some painkiller such as petidina.

About the nodules:

-The subcutaneous nodules or pannicular sacroiliac hernia could be palpated in the sacroiliac region.

-They were single or multiple. Size from 1 to 4.5 cm. Slightly movable.

-Consistency was as lipoma.

-While pressing the nodules, pain increased.

-Lasegue was negative. Knee reflexes were normal.

-Pain got much better with BLOCKADE with procaine.

Patient management with pannicular sacroiliac hernia

-The patients with mild symptoms received just the procaine blockade with massage and physiotherapy.

-The patients with severe pain, and nodules from 1 to 2 cm, received first procaine blockade and, in certain cases, like the ones that just got relief for some hours, they did surgical removal.

  • They did 59 operations with a 90% of success.
  • 43 cases didn’t have any RELAPSE between 3 months and 1 year and a half.
  • With 2 cases there was a hemorrhage.
  • 5 cases had a relapse of the pain, some underwent new surgery.

Tong’s surgery technique to remove pannicular sacroiliac hernia

Basically they excise the fatty tumor and ENLARGE the hole of the fascial defect, to avoid new herniation and incarceration. When incision in superficial fascia, it reveals the fatty tumor. The limits are CLEAR, except from the base. The surface is smooth. When the vessels and the nerves are cut there is a sharp pain. The fascial hole is enlarged.

Histology shows normal fatty tissue sometimes with some lymphocyte infiltration.

Some patogenic notes: The pathology is related to the weakness of the fascia on this region and the fact that the peripheral nerves with the vessels cross the fascia through holes.

-There is a rich deep subfascial fat in the region especially in obese women.

-The fatty tissue from the hernia is surrounded by connective tissue, which differentiates it from the surrounding superficial fat.

-The size of the hole in the fascia and the hernia itself are incoherent.

-If the hernia is next to the nerve and the vessels, the pain is worse.


Published in June 2018 By Marta Cañis Parera   ORCID iD icon


  • 1981 Tong W.T. annicular sacroiliac hernia. Report of 50 cases]. Chinese journal of surgery (Zhonghua wai ke za zhi) 1981 (4) p.231 ISSN: 0529-5815.