• Users Online: 633
  • Print this page
  • Email this page


 
 
Table of Contents
CASE REPORT
Year : 2021  |  Volume : 18  |  Issue : 2  |  Page : 142-145

Computed tomography diagnosis of posterior rectus sheath hernia causing intermittent small bowel obstruction


1 Department of Radiology, Apollo Hospitals, Bengaluru, Karnataka, India
2 Department of GI, HPB and Minimal Access Surgery, Apollo Hospitals, Bengaluru, Karnataka, India

Date of Submission26-Feb-2021
Date of Acceptance21-Mar-2021
Date of Web Publication17-May-2021

Correspondence Address:
Aruna Raman Patil
Department of Radiology, Apollo Hospitals, Bannerghatta Road, Bengaluru - 560 076, Karnataka
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/am.am_17_21

Rights and Permissions
  Abstract 

Hernias of the posterior rectus sheath are a rarer type of interparietal hernia with only few cases reported up to date. Majority are postsurgical and posttraumatic. Clinical diagnosis may be challenging and imaging is often utilized for diagnosis. Computed tomography (CT) is the preferred imaging technique as it maps out the type, extent, contents, and associated complications. We report a case of posterior rectus sheath hernia with small bowel obstruction diagnosed on CT and managed successfully using laparoscopic primary repair.

Keywords: Bowel obstruction, hernia, posterior rectus sheath


How to cite this article:
Patil AR, Medipally M, Bansal A, Chakma N. Computed tomography diagnosis of posterior rectus sheath hernia causing intermittent small bowel obstruction. Apollo Med 2021;18:142-5

How to cite this URL:
Patil AR, Medipally M, Bansal A, Chakma N. Computed tomography diagnosis of posterior rectus sheath hernia causing intermittent small bowel obstruction. Apollo Med [serial online] 2021 [cited 2021 Jun 21];18:142-5. Available from: https://www.apollomedicine.org/text.asp?2021/18/2/142/316402


  Introduction Top


Hernia refers to the abnormal protrusion of an organ or tissue through a defect in its surrounding walls. A hernia can be congenital or acquired. Common types of hernia include inguinal, femoral, ventral, and incisional. Less common hernias include interparietal, Richter, and Littre hernias of the abdominal wall and sciatic, obturator, and perineal hernias in the pelvis.[1]

Posterior rectus sheath hernia is a type of interparietal hernia where the hernial sac lies between the various layers of the abdominal wall muscles and does not exit into the subcutaneous tissue.[1],[2] Specifically, in this type of hernia, the sac protrudes into the potential space between the posterior rectus sheath and the rectus muscle. They are prone to complications as the defect is small and clinically occult in most cases.

This case report discusses the presenting features, diagnosis, and treatment of posterior rectus sheath hernia.


  Case Report Top


A 72-year-female presented with 7 days history of vomiting and abdominal pain to the emergency department. There were no episodes of fever or diarrhea. Patient recollected two similar episodes a month ago which were managed conservatively. History of prior femoral hernia repair 2 years back with no further details elicitable. On physical examination, fullness was felt in the infra umbilical region. Basic laboratory investigations including complete blood count and inflammatory markers were within normal limits.

Contrast-enhanced computed tomography (CECT) of the abdomen was ordered to evaluate the cause. CECT was done with intravenous administration of 110 ml of Omnipaque (Iohexol) and images were acquired in the venous phase (40–60 s delay). CT showed dilatation of ileal loops (3.5–4 cm in diameter) with herniation of few loops through a defect between the rectus muscle and posterior rectus sheath below the level of umbilicus [Figure 1] and [Figure 2]. Herniated mesentery showed congestion and minimal fluid within the sac [Figure 2]. There were areas of focal wall thickening and narrowing in proximal ileal loops [Figure 3]. The posterior rectus sheath defect measured 3 cm × 3 cm on the left infraumbilical aspect. The vascularity of the herniated loops was normal with no signs of strangulation. Radiological diagnosis was posterior rectus sheath hernia with obstruction and focal ileal thickening at places probably representing sequelae to prior herniations.
Figure 1: Contrast-enhanced computed tomography axial section in venous phase shows herniation of dilated bowel loops (arrow) between rectus muscle and posterior rectus sheath (arrow heads)

Click here to view
Figure 2: (a and b) Contrast-enhanced computed tomography sagittal section in venous phase shows herniation of small bowel through the defect (arrows in “a”) in posterior rectus sheath (arrowheads). Arrows in “b” show congested mesenteric vessels suggesting early strangulation

Click here to view
Figure 3: Contrast-enhanced computed tomography in coronal section shows areas of focal ileal wall thickening (thick arrow) secondary to recurrent herniation. Thin arrows indicate dilated small bowel loops

Click here to view


In view of hernia-related small obstruction, laparoscopic release and repair were attempted. Intraoperatively, defect was identified in the left posterior rectus sheath with ileal loops herniating, and few adhered within the retro rectus space [Figure 4]. Anatomical repair of defect was done after releasing the adhered small bowel loops. Postoperative period was uneventful.
Figure 4: (a and b) Intraoperative demonstration of the posterior rectus sheath defect (arrows) with small bowel herniation (*). Curved arrow in “b” shows the potential space between the rectus muscle and posterior rectus sheath cleared of the herniated small bowel

Click here to view



  Discussion Top


Hernia refers to abnormal protrusion of an organ or tissue through a defect in its surrounding walls. A hernia can be congenital or acquired and the common types of hernia include inguinal, femoral, ventral, and incisional.

Posterior rectus sheath hernias are a type of interparietal hernias where the hernial sac lies between the various layers of the abdominal wall muscles and does not exit into the subcutaneous tissue.[1],[2],[3] Specifically, in this type of hernia, the sac protrudes into the potential space between the posterior rectus sheath and rectus muscle [Figure 5].
Figure 5: Illustration demonstrating posterior rectus sheath defect and herniation

Click here to view


The rectus abdominis muscle extends between the ribcage and pubis and is supplied by the lower intercostal and corresponding segmental abdominal nerves. This muscle is enclosed within the rectus sheath which is formed by the aponeuroses of the lateral abdominal muscles.[2],[4],[5] The rectus sheath encloses the rectus abdominis muscle and pyramidalis muscles. It is formed by the aponeuroses of the flat abdominal muscles. The anterior layer of the rectus sheath consists of the external oblique aponeurosis supplemented by the anterior aponeurotic layer of the internal oblique aponeurosis, whereas its posterior layer is formed by the aponeurosis of the transversus abdominis muscle and the posterior aponeurotic layer of the internal oblique aponeurosis up to the level of the arcuate line.

However, below the arcuate line, it is reduced to the fascia transversalis because all three aponeuroses pass anterior to the rectus abdominis muscle. Although strong, the rectus sheath shows sites of minor resistance and serves to explain that these hernias can also occur without previous traumatic or surgical history.[6]

Spontaneous posterior rectus sheath hernias were first documented in 1937. They are exceedingly rare with a case series in 2009 identifying only eight cases in the literature with two additional cases reported in 2014 and 2017.[7],[8],[9]

A majority of posterior rectus sheath hernia cases are postsurgical or posttraumatic. The remainder occurs in persons without surgery and is often reported as having a congenital origin.[7] These hernias are prone to complications as the defect is small and clinically occult in most cases.

Posterior rectus sheath hernia is usually diagnosed with imaging studies such as ultrasonography, magnetic resonance imaging (MRI), and computed tomography (CT). Ultrasound (USG) is the first-line imaging investigation for hernia detection particularly in patients with a palpable swelling or cough impulse.[1] USG has a major advantage of dynamic assessment with and without a Valsalva maneuver. In posterior rectus sheath hernia, USG has limited role, especially if the contents are bowel loops containing air.

CT is optimal for assessing most hernias in the acute phase, whereas MRI findings are more informative if there is reasonable likelihood of a musculoskeletal cause of the symptoms. CT and MRI are both excellent modalities for the assessment of palpable abdominal masses in the nonacute phase.[1],[3] CT assessment is usually performed with oral and IV contrast media; Valsalva maneuvers can also be used.

If multi–detector row CT is performed for the evaluation of known or suspected hernias, postural maneuvers (e.g., prone or lateral decubitus patient positioning), and maneuvers to increase intraabdominal pressure (e.g., straining, Valsalva maneuver) can help depict subtle hernias that would otherwise be missed.[1] Intravenous administration of contrast material is necessary for the characterization of the vascular supply. The use of neutral contrast over positive oral contrast is preferred for better visualization of bowel loops. Complications such as obstruction, incarceration, and strangulation are well evaluated[1],[3] on CT.

Multiplanar reformatted images provide important information in addition to that provided by axial images in that they may better delineate the size and shape of the hernia sac and associated complications.[1]

Laparoscopy has also been used for diagnostic and therapeutic purposes.[3],[10] However, definitive diagnosis is often made during surgery.[4] Primary closure is the preferred choice of treatment. Prosthetic repair in larger defects.[5],[9],[11]

The common differential is Spigelian hernia (1%–2% of all hernias) result from a protrusion of preperitoneal fat and a congenital or acquired defect in the Spigelian aponeurosis. The term Spigelian aponeurosis refers to the part of the aponeurosis of the transversus abdominis muscle between the linea semilunaris laterally and the lateral edge of the rectus abdominis muscle medially. Most Spigelian hernias lie in the “spigelian hernia belt,” a 6-cm-wide transverse zone above the interspinal plane. Lower Spigelian hernias are rare and should be differentiated from direct inguinal hernias and supra vesical hernias.[12],[13]


  Conclusion Top


Posterior rectus sheath hernias are uncommon and they may present with severe abdominal pain and incarceration, which can lead to an increased risk of bowel obstruction and strangulation if left untreated. Imaging, especially CT helps in the diagnosis and surgical planning.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient (s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initial s will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
Aguirre DA, Santosa AC, Casola G, Sirlin CB. Abdominal wall hernias: Imaging features, complications, and diagnostic pitfalls at multi-detector row CT. Radiographics 2005;25:1501-20.  Back to cited text no. 1
    
2.
Flament JB, Avisse C, Delattre JF. Anatomy of the abdominal wall. In: Bendavid R, Abrahamson J, Arregui ME, Flament JB, Phillips EH, editors. Abdominal Wall Hernias, Principles and Management. Heidelberg, Germany: Springer-Verlag; 2001. p. 41-2.  Back to cited text no. 2
    
3.
Etawo US, Elechi EN. Interparietal hernias: Analysis of six cases with literature review. Br J Clin Pract 1987;41:1068-70.  Back to cited text no. 3
    
4.
Reznichenko A. Case of rare abdominal wall hernia. J Curr Surg 2014;4:99-100.  Back to cited text no. 4
    
5.
Johnson TG, Von SJ, Hope WW. Clinical anatomy of the abdominal wall: Hernia surgery. OA Anatomy 2014;2:3.  Back to cited text no. 5
    
6.
Gangi S, Sparacino T, Furci M, Basile F. Hernia of the posterior lamina of the rectus abdominis muscle sheath: Report of a case. Ann Ital Chir 2002;73:335-7.  Back to cited text no. 6
    
7.
Lenobel S, Lenobel R, Yu J. Posterior rectus sheath hernia causing intermittent small bowel obstruction. J Radiol Case Rep 2014;8:25-9.  Back to cited text no. 7
    
8.
Sogani J, Hentel KD, Belfi L. Emergency IMAGING: Abdominal Pain 6 months after cesarean delivery. Emerg Med 2017;49:89-91.  Back to cited text no. 8
    
9.
Losanoff JE, Basson MD, Gruber SA. Spontaneous hernia through the posterior rectus abdominis sheath: Case report and review of the published literature 1937-2008. Hernia 2009;13:555-8.  Back to cited text no. 9
    
10.
Gangi S, Sparacino T, Furci M, Basile F. Hernia of the posterior lamina of the rectus abdominis muscle sheath: Report of a case. Ann Ital Chir 2002;73:335-7.  Back to cited text no. 10
    
11.
Whitson BA, Ose KJ. Spontaneous posterior rectus sheath hernia: A new clinical entity? Hernia 2007;11:445-7.  Back to cited text no. 11
    
12.
Skandalakis PN, Zoras O, Skandalakis JE, Mirilas P. Spigelian hernias: Surgical anatomy, embryology, and technique of repair. Am Sur 2006;72:42-8.  Back to cited text no. 12
    
13.
Hirabayashi T, Ueno S. Rare variant of inguinal hernia, interparietal hernia and ipsilateral abdominal ectopic testis, mimicking a spiegelian hernia. Case report. Tokai J Exp Clin Med 2013;38:77-81.  Back to cited text no. 13
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]



 

Top
 
  Search
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

 
  In this article
Abstract
Introduction
Case Report
Discussion
Conclusion
References
Article Figures

 Article Access Statistics
    Viewed306    
    Printed5    
    Emailed0    
    PDF Downloaded9    
    Comments [Add]    

Recommend this journal