*Graded Specialist (Surgery), #Senior Adviser (Surgery and Orthopedics), **Graded Specialist (Radiology), 7 Air Force Hospital, Nathu SinghRoad, Kanpur 208 004. +Classified Specialist (Surgery), Army Hospital (R&R), New Delhi.

Received : 18.03.08; Accepted : 21.11.08 E-mail : docam@rediffmail.com

Case Report

Introduction

Appendectomy is a common surgery and incisionalhernia following appendectomy is uncommon,

occurring in less than 0.12% of patients [1]. Postappendectomy interstitial incisional hernia is extremelyrare [2].

In 1911, Hoguet first called attention to the occurrenceof right inguinal hernia following appendectomy withdrained wounds. Many of these had not only a rightinguinal hernia but also an associated postoperativehernia at the site of the appendectomy scar. Hoguetand Watson attributed the occurrence of the inguinalhernia to a weakening of the abdominal wall followinginjury to the ilio-inguinal and ilio-hypogastric nerves [3].

A case of post appendectomy interstitial hernia isreported for the rarity of the condition and review ofliterature.

Case Report

A 32 year old male presented with pain and a bulge in theright lower quadrant of abdomen of three years duration. Hehad undergone an appendectomy for perforated appendicitisthree years back. The postoperative period was complicatedby surgical site infection which was managed conservatively.The bulge was visible only on standing and the painaggravated on doing strenuous activity. There were noassociated bowel symptoms. Physical examination revealeda well-healed appendectomy scar with a diffuse swellingvisible centered over the scar on standing (Fig. 1). This bulgeincreased in size on coughing and disappeared on lyingdown. The muscular tone of the rest of the abdomen wasgood. Ultrasound examination of the abdomen showed ahernial sac containing bowel just under the scar; under thecover of the external oblique (Fig. 2). A diagnosis of postappendectomy interstitial incisional hernia was made and thepatient was scheduled for surgery.

A 5 cm transverse incision was made starting from thescar in its upper part and extending medially. The externaloblique aponeurosis was divided in the line of incision. The

attenuated internal oblique fibres were split to reveal thehernial sac containing bowel (Fig. 3). The hernial sac wasdissected from its place between external and internal obliquemuscles and reduced. Preperitoneal space was then developedand a 15x15 cm mesh placed. The muscles were closed over itwith 1-0 vicryl. The external oblique aponeurosis was suturedwith 1-0 prolene.

The postoperative course was uneventful. He wasdischarged on the 10th post operative day after suture removal.He was reviewed at one and six months after surgery whereinhe was asymptomatic, without recurrence of hernia (Fig. 4).

Discussion

Despite developments in surgical techniques,operative devices and materials, incisional hernia remainsa significant problem in abdominal surgery [4]. Thereported incidence of incisional hernias followingabdominal surgeries is about 10 % [5]. Abdominal walldefects occur within the first 5 years after the surgicalincision is made, but many develop later [6]. Theincidence depends on a number of factors includingpatient factors like old age, male sex, obesity, smoking,diabetes, steroid use and some surgical factors likeemergency surgery, bowel surgery, suture type andtechnique, chest infection, abdominal distension andwound infection. In our case, the contributing factorswere male sex, emergency surgery and post-operativewound infection.

Hernia following appendectomy through a gridironmuscle-splitting incision is usually the result of infectionof wound in advanced appendicitis, with or withoutperforation, and is associated with local purulentperitonitis [7]. Other common causes are placing a drainthrough the incision and tying sutures too tightly in thefleshy internal oblique and transverse abdominis musclesleading to necrosis of the muscle [2].

Two types of hernias occur. In the more commontype, the hernia passes through all the layers of the

Interstitial Incisional Hernia following AppendectomySqn Ldr A Kumar*, Wg Cdr N Saidha+, Gp Capt TS Ramakrishnan#, Wg Cdr S Sahu**

MJAFI 2009; 65 : 176-177

Key Words : Interstitial hernia; Incisional hernia; Appendectomy

MJAFI, Vol. 65, No. 2, 2009

Interstitial Incisional Hernia following Appendectomy 177

abdominal wall. Less common is the interstitial type inwhich the hernia passes through a defect in thetransverses abdominis and internal oblique muscles, butnot through the intact aponeurosis of the external oblique[2]. This type can be missed easily. In patients suspectedof this condition, ultrasound scanning or computedtomography should confirm the diagnosis [8].

Repair of post appendectomy incisional hernias canbe undertaken in the form of anatomical repair. Whenthe tissues are thin and atrophic, an overlap type of repairmay be used for the two inner muscles but these casesare best treated with a sheet of polypropylene mesh,with a margin measuring at least 6-8 cm beyond theperiphery of the defect, placed between the peritoneumand transverses abdominis muscle [9]. In our case, thepatient underwent a pre-peritoneal mesh repair becauseof the attenuated tissues.

This case assumes significance since it is the rareinterstitial type of post appendectomy incisional hernia,and not many cases find mention in review of literature.

Conflicts of Interest

None identified

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incisional hernia after open appendicectomy. Current Surgery2000; 57:79-80.

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3. Fisher HC. Post appendicectomy Interstitial Inguinal Hernia.Ann Surg 1946;123: 419–26.

4. Feliciano DV. Incisional hernias as emergencies. In:Bendavid R,Abrahamson J, Arregui M, Flament JB, Phillips ED, eds.Emergency surgery. Abdominal wall hernias. New York :Springer-Verlag Inc 2001;582-7.

5. Popovic JR, Hall MJ. 1999 National hospital discharge survey.Adv Data 2001; 3:1-20.

6. Chowbey PK, Sharma A, Mehrotra M, Khullar R, Soni V,Baijal M. Laparoscopic repair of ventral/incisional hernias. JMin Access Surg 2006; 2:192-8.

7. Abou-Nukta F, Bakhos C, Arroyo K, et al. Effects of delayingappendectomy for acute appendicitis for 12 to 24 hours. ArchSurg 2006;141:504-6.

8. Toms AP, Dixon AK, Murphy JM, Jamieson NV. Illustratedreview of new imaging techniques in the diagnosis of abdominalwall hernias. Br J Surj 1999; 86:1243-9.

9. Duce AM, Lozano O, Villeta R, et al. Incisional hernia followingappendectomy. Surgical experience. Hernia 1998; 4: 169-71.

Fig. 1 : Pre-operative photograph of patient showing the hernialbulge centered over the appendectomy scar.

Fig. 3 : Per-operative photograph showing the hernial sac afterdivision of the external oblique aponeurosis.

Fig. 2 : Pre-operative ultrasound image showing the interstitialincisional hernial sac (red arrows) under the cover of externaloblique (green arrows, M1). M: Internal oblique muscle, B:Bowel loop, C: Campers fascia.

Fig. 4 : Ultrasound image at six months (post operative) shows norecurrence. M: Muscle.