J Korean Neurosurg Soc.  2015 Feb;57(2):123-126. 10.3340/jkns.2015.57.2.123.

Decompression of the Sciatic Nerve Entrapment Caused by Post-Inflammatory Scarring

• Son BC
• Kim DR
• Jeun SS
• Lee SW

• KMID: 2191194
• DOI: http://doi.org/10.3340/jkns.2015.57.2.123

Abstract

A rare case of chronic pain of entrapment neuropathy of the sciatic nerve successfully relieved by surgical decompression is presented. A 71-year-old male suffered a chronic right buttock pain of duration of 7 years which radiating to the right distal leg and foot. His pain developed gradually over one year after underwenting drainage for the gluteal abscess seven years ago. A cramping buttock and intermittently radiating pain to his right foot on sitting, walking, and voiding did not respond to conventional treatment. An MRI suggested a post-inflammatory adhesion encroaching the proximal course of the sciatic nerve beneath the piriformis as it emerges from the sciatic notch. Upon exploration of the sciatic nerve, a fibrotic tendinous scar beneath the piriformis was found and released proximally to the sciatic notch. His chronic intractable pain was completely relieved within days after the decompression. However, thigh weakness and hypesthesia of the foot did not improve. This case suggest a need for of more prompt investigation and decompression of the chronic sciatic entrapment neuropathy which does not improve clinically or electrically over several months.

Keyword

Entrapment neuropathy; Neurolysis; Piriformis; Sciatic nerve

MeSH Terms

Abscess
Aged
Buttocks
Chronic Pain
Cicatrix*
Decompression*
Decompression, Surgical
Drainage
Foot
Humans
Hypesthesia
Leg
Magnetic Resonance Imaging
Male
Muscle Cramp
Pain, Intractable
Sciatic Nerve*
Thigh
Walking

Figure

• 

  Fig. 1 A physical photograph and magnetic resonance imaging showing the gluteal abscess in the right hip seven years ago. A : A photograph show-ing dimple-like postoperative scars in the patient's buttock. B : A gadolinium-enhanced T1 coronal image shows an irregularly enhancing band-like lesion (arrow) encroaching the sciatic nerve (arrowheads).

• 

  Fig. 2 Intraoperative photographs showing sciatic nerve entrapment due to post-inflammatory adhesion scar. A : After dissecting the fibers of the gluteus maximus, severely compressed and flattened sciatic nerve (white arrow) was noted. The adhesion scar (white arrowhead) was elevated with Kelly clamp. The posterior cutaneous nerve of the thigh (black arrow) and piriformis muscle (black arrowhead) were found and neurolysis was done. B : A schematic drawing of the exposure.

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