A Guide for Identification of Different Types of Hernias

groin (Figure 2). It is a case of left sided femoral hernia. In order to differentiate it from other types of swellings, one has to look for certain features. For instance, it presents as a rounded swelling on inspection. Associated features include increase in size with physical activity like walking or straining and relative reduction in size when lying down. Clinically, it can be elicited by asking the patient to cough. An increase in size following coughing would confirm it as a hernia. It is important to distinguish it from the more common inguinal hernia. For this, one needs to look at the boundaries of this swelling. It can be appreciated that the medial most borders are just lateral to the path of inguinal canal. This is a very useful visual distinguishing feature for femoral hernias as inguinal hernias present initially along the path of inguinal canal and later in the scrotal region whereas femoral hernias present along the path of the femoral canal. Another way to distinguish it involves palpation of swellingneck of femoral hernia lies below and lateral to the pubic tubercle while that of inguinal hernia lies above and medial to the pubic tubercle.

groin ( Figure 2). It is a case of left sided femoral hernia. In order to differentiate it from other types of swellings, one has to look for certain features. Firstly, it presents as a rounded swelling on inspection. Associated features include increase in size with physical activity like walking or straining and relative reduction in size when lying down. Clinically, it can be elicited by asking the patient to cough. An increase in size following coughing would confirm it as a hernia. It is important to distinguish it from the more common in inguinal hernia. For this, one needs to look at the boundaries of this swelling. It can be appreciated that the medial most borders are just lateral to the path of inguinal canal. This is a very useful visual distinguishing feature for femoral hernias as inguinal hernias present initially along the path of inguinal canal and later in the scrotal region whereas femoral hernias present along the path of the femoral canal. Another way to distinguish it involves palpation of swelling-neck of femoral hernia lies below and lateral to the pubic tubercle while that of inguinal hernia lies above and medial to the pubic tubercle.

Incisional Hernia (Reducible)
An incisional hernia ( Figure 3) is a protrusion of tissue that forms at the site of a healing surgical scar. While a distinct scar of a prior surgery is visible in Figure  4, the same cannot be appreciated in Figure 5. Hence, it becomes important to take a detailed history of any past surgery to differentiate incisional hernias from other types of hernias. These hernias are reducible which means that the contents of the swelling can be reduced into the abdominal cavity at rest, when the intro-abdominal pressure is not high. In both these cases, a positive cough impulse could be elicited. Cough

Introduction
A hernia is defined as an abnormal protrusion of a viscus or part of a viscus through a normal or abnormal opening in the cavity in which it is contained. It is an area of weakness or disruption of the fibromuscular tissues of the body wall. Inguinal hernia is the most common type of hernia (73%), followed by incisional (15%) and femoral hernia (7%). This article describes these common types of hernias with an example each, along with their major characteristics and identification points.

Inguinal Hernia
This case is that of a bilateral inguinal hernia with the scrotal swelling on the right side being larger than that on the left (Figure 1). Typical presentations include swelling in the inguinal or scrotal region. The usual features for identification of hernia apply here as well but this patient has a severely enlarged globular swelling that has made even identification of the penile shaft difficult. This is not usually seen in other causes of scrotal swelling such as testicular cancer or hydrocoele and is indicates that the content of the swelling has come from outside the scrotal sac. This is a very useful visual identification feature. Hernias of this size tend to be irreducible. Another important visual finding in this case can be the appreciation of redness of the scrotal swelling. It is a sign of incarceration of hernia and warrants further physical examination to confirm the same.

Femoral Hernia
The patient presented with a globular swelling in the    always be clearly appreciable ( Figure 6). Hence, it becomes important to take a detailed history of any past surgery. Irreducible hernias cannot be pushed back, manually, through the opening in the abdomen and they are trapped outside the abdominal muscle wall. Hence, cough impulse cannot be elicited in these patients. Unlike reducible incisional, where the gap in the anterior abdominal wall can be distinctly appreciated with the fingers on contracting the abdominal wall muscles, it may not be felt properly in cases of irreducible hernias.
impulse is the most specific sign for diagnosis of a hernia on clinical examination. The expansile impulse over the swelling when the patient coughs implies a positive cough impulse. Movement or increase in tension of a swelling without expansion is not considered as a positive cough impulse.