How Often Does a Patient Develop A Contralateral Inguinal Hernia After a Previous Repair?

Patient Presentation

A 10-month-old male came to clinic after his parents had noticed a new mass in his left groin for 2 days.
The infant was not bothered by it, and it seemed to be bigger or smaller at different times. It becomes larger with crying. He had normal urination and there was no discoloration noted.
The past medical history revealed that he had 2 ear infections and some upper respiratory infections but nothing recently.
The pertinent physical exam showed a healthy male with normal growth parameters who was afebrile.
Skin, HEENT, lung, cardiac and abdominal examinations were normal. The standing genitourinary examination showed no overlying redness on the skin.
Palpation revealed a 2 cm in length x 1 cm in width mass in the left groin that followed through the inguinal canal and a bowel loop was palpable.
The recumbant examination did not show a decrease in the size of the mass but was easily reducible with a small amount of upward/lateral finger tip pressure.
The patient was referred to a surgeon who confirmed the diagnosis of a left indirect inguinal hernia. During the surgery, the contralateral side was explored using peritoneoscopy and showed no patent process vaginalis. The left hernia was repaired without incident and he had an unremarkable clinical course.

Indirect inguinal hernias occur in about 1-5% of infants. They occur on the right side (60%), left side (30%) and bilaterally (10%) and they are more common in premature infants of both sexes.
The male : female ratio of inguinal hernias is 4-8 : 1.
Most inguinal hernias are indirect (i.e. the hernia passes through the internal inguinal ring and down the inguinal canal); only 2% of all hernias in children are direct hernias (i.e. the hernia directly protrudes through the floor of the inguinal canal).

Hernias in children occur because the processus vaginalis (the peritoneum attached to the testicle) trails behind the testis and usually this connection is obliterated, but sometimes it closes during infancy, childhood and occasionally adulthood.
If the closure does not occur, abdominal contents may herniate into the potential space causing a hernia. If the potential space is small, often covered by internal oblique and transverse abdominal muscles, then only fluid may enter causing a communicating hydrocoele. A non-communicating hydrocoele is caused when there is incomplete closure causing fluid to be trapped in the hydrocoele but with no connection to the abdomen.

The main problem with inguinal hernias is the risk of incarceration and strangulation. If incarcerated, the hernia usually has a firmer feel on palpation with discoloration, edema, and tenderness present. It is also not reducible. The child is often fussy or crying inconsolably, unwilling to feed and/or has emesis.
Urgent surgical consultation and treatment is necessary to prevent compromise of the vascular supply.

Patients should be examined in the upright and supine position. An indirect hernia is usually felt from the external ring to the pubic tubercle and is smooth and a bowel loop may be palpated. An ovary may be palpated in the canal in females. Increased abdominal pressure may increase the hernia size (i.e. Valsalva maneuver).
Boys need to have both testicles identified to rule out an undescended or retractile testicle. Transillumination is helpful to differentiate a hernia from a hydrocoele (during transillumination a hydrocoele looks like a homogeneous water filled balloon). Transillumination does not rule out a hernia though as fluid filled bowel may also appear similarly.
When the hernia is rubbed against the spermatic cord it may feel like 2 pieces of silk rubbing together giving rise to the “silk sign.” The hernia should be checked for reducibility with mild pressure exerted through the ring. This often occurs spontaneously and parents may give the history that the mass appears to come and go.

Learning Point
Treatment for inguinal hernias is usually elective herniorrhaphy to prevent incarceration and subsequent strangulation. Emergent herniorrhaphy for bowel obstruction also occurs.
There are 3 basic surgical procedures. Each includes high ligation of hernia sac and then excision of the patent sac with anatomic closure, plication of the floor of the inguinal canal, or reconstruction of the canal floor.

As age, sex, physical examination or other non-invasive diagnostic tests cannot accurately determine the presence of a contralateral asymptomatic hernia, potential exploration of the contralateral side is debated. About 30% of patients will eventually develop a contralateral inguinal hernia after previous repair. Some advocate for exploration in patients with known reasons for increased intraabdominal pressure such as a ventriculoperitoneal shunt or peritoneal dialysis.
The main advantage is the potential avoidance of a second surgery and disadvantages include increased operating time, and potential injury to the blood supply or vas deferens.
Peritoneoscopy during the hernia repair can be used to help determine if a child has a contralateral patent processus vaginalis. The false negative rate for peritoneoscopy is ~1%. If a patent processes vaginalis is found, then it is generally recommended that it be repaired during the present surgery.

Questions for Further Discussion
1. How does a femoral hernia differ from an inguinal hernia?
2. What are the indications for an umbilical hernia repair?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Information prescriptions for patients can be found at MedlinePlus for this topic: Hernia
and at Pediatric Common Questions, Quick Answers for this topic: Hernias

To view current news articles on this topic check Google News.

Hebra A. Pediatric Hernias. eMedicine.
Available from the Internet at (rev. 5/30/2006, cited 9/7/2006).

Rudolph CD, Rudolph’s Pediatrics. 21st edit. McGraw-Hill, New York, NY. 2003:1742.

ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    5. Patients and their families are counseled and educated.
    7. All medical and invasive procedures considered essential for the area of practice are competency performed.
    8. Health care services aimed at preventing health problems or maintaining health are provided.
    9. Patient-focused care is provided by working with health care professionals, including those from other disciplines.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Practice Based Learning and Improvement
    12. Evidence from scientific studies related to the patients’ health problems is located, appraised and assimilated.

  • Systems Based Practice
    23. Differing types of medical practice and delivery systems including methods of controlling health care costs and allocating resources are known.
    24. Cost-effective health care and resource allocation that does not compromise quality of care is practiced.
    26. Partnering with health care managers and health care providers to assess, coordinate, and improve health care and how these activities can affect system performance are known.

    Donna M. D’Alessandro, MD
    Associate Professor of Pediatrics, Children’s Hospital of Iowa

    October 2, 2006