Groin Explained

Overview

The groin is also referred to as the inguinal portion of the body. It is located anteriorly in the lower region within the abdominal wall, inferiorly surrounded by the thighs, with the pubic tubercle in the medial part and superolateral surrounded by the anterior superior iliac spine (ASIS). The inguinal canal has a tubular form that runs inferomedially. In males, it consists of the spermatic cord, whereas in females consist of the round ligament. The length of the inguinal canal is approximately 4-6 cm which changes from childhood to adulthood.

Inguinal ligament forms the floor of the inguinal canal, also called as Poupart ligament. This ligament is composed of the external oblique aponeurosis. It overlaps and attaches to the ASIS extending till the pubic tubercle. The folded edge is known as the shelving edge that plays an important role for clinicians in the management of hernia repairs.

The groin region in a plastinated female body. Image by shawn

Structure

Groin or the inguinal canal consists of an anterior wall, posterior wall, floor and roof. The anterior wall is composed of the external oblique aponeurosis. The transversalis muscle forms the posterior wall. The floor of the groin or inguinal canal is composed of the inguinal ligament. This ligament is a thickened portion formed by the external oblique aponeurosis. The roof is a complex structure formed by the combination of fibres of two muscles (transversus abdominis and internal oblique muscle) with the aponeurosis and the conjoint tendon. The conjoint tendon forms an important part of the posterior wall in the medial portion.

The adductor muscles in the groin are most commonly subject to injury, and there comprises the adductor longus, adductor magnus, adductor brevis, gracilis, and pectineus.

There are two openings through the inguinal canal:

  • The deep or internal ring is present above the center of the inguinal ligament, and laterally surrounded by the epigastric vessels. This ring is made by the transversalis fascia, providing a posterior covering to the contents of the inguinal ring.
  • The superficial or external ring constitutes the inguinal canal’s terminal end. This ring is present superior to the pubic tubercle. The external ring has a triangular shape which is formed by the fibres of the external oblique muscle. These fibres cover the inguinal contents and descend into the scrotal area.
Anatomy of the groin. Image by
Mikael Häggström

Function

It is important to understand the anatomy of the inguinal canal or groin so that the surgeon is well aware of different types of groin hernia arising in the region, and also for performing various kinds of surgical repair. The mid-inguinal point demarcates the region between the pubic symphysis and the anterior superior iliac spine. Deep to this location, there is a femoral artery that enters the lower limb. The palpation of the femoral artery is possible below the inguinal ligament. The groin acts as a gateway for structures between the intra- and extra-abdominal components. It transmits the gonadal vessels , spermatic cord and lymphatics in males, while in females allows the passage of the round ligament of the uterus.

The major role of the muscles of the inner thigh is to pull the legs towards the midline, with a movement known as adduction.

Illustration of the muscles of the groin, showing the adductor longus, adductor magnus, adductor brevis, gracilis, and pectineus. Image by OpenStax

Neurovascular Supply

There are two important nerves that pass through the various structures of the inguinal canal. This includes the ilioinguinal, genitofemoral nerves, and iliohypogastric nerve. The iliohypogastric nerve does not pass through the inguinal canal, however, it supplies skin sensation above the genitalia. The ilioinguinal nerve, a branch of L1 passes through the deep inguinal openings in addition to the cord structures. It supplies sensation to the medial and upper thigh as well as the anterior perineum. The genitofemoral nerve is a branch of the L1-L2 spinal nerve roots. It divides into two branches namely, the genital branch and the femoral branch where the former passes through the deep inguinal ring and the latter passes below the inguinal canal.

The femoral artery supplies blood to the groin region. As a continuation of the external iliac artery, the common femoral artery is formed below the inguinal ligament. The artery is present medially to the middle portion of the inguinal ligament within the inguinal crease region.

Illustration of the arteries supplying blood to the lower limb, showing the femoral artery reaching the groin. Image by Medical gallery of Blausen Medical 2014

Clinical Relevance and Associated Diseases

Inguinal hernias are associated with the inguinal area and canal. Groin hernia refers to the inguinal and femoral hernias, that show up as groin pain. Certain diseases are encountered within this area such as hydrocele and undescended testis and, if not treated in time, lead to chronic pain.

Groin Strain

Groin strain, also known as a groin pull, refers to the damage of one of the muscles in the inner thigh due to excessive stretch or the muscle being torn.

Indirect Hernia

This type of hernia occurs when the peritoneal sac enters into the inguinal canal through the deep inguinal ring. Through the external inguinal ring, there is the protrusion of the hernia that manifests as groin pain.

Direct Hernia

In this type of groin hernia peritoneal sac enters via the inguinal canal as a result of defect or impairment in the posterior portion of the inguinal canal, mostly the transversus abdominis.

Illustration of an inguinal hernia. Image by Medical gallery of Blausen Medical 2014

Femoral Hernia

In this type of injury, the hernial sac protrudes through the femoral ring. The femoral ring constitutes the medial portion of the femoral canal. There is a difference in the management of surgical repair of femoral hernia and inguinal hernia as the latter is conducted by an open approach.

Illustration of the anatomy of the groin and annotation of the most common sites for inguinal and femoral hernias. Image by Dennis M. DePace, PhD

Hydroceles

A hydrocele happens due to the prolonged patency of the processus vaginalis which may occur along with indirect hernia. In hydrocele, there is an accumulation of fluid within the scrotum leading to persistent groin pain.

Illustration of a hydrocele, which presents an accumulation of fluids in the scrotum with or without communication with the abdominal cavity. Image by Pixabay

Malignancy of the groin

The inguinal area is also involved with the drainage of lymph nodes and therefore may result in lymphadenopathy from infections and malignancies. Certain malignancies of the groin area include lipoma of the spermatic cord and malignant tumours like rhabdomyosarcoma.

References

1. Palisch A, Zoga AC, Meyers WC. Imaging of athletic pubalgia and core muscle injuries: clinical and therapeutic correlations. Clin Sports Med 2013;32:427-47.

2. Rambani R, Hackney R. Loss of range of motion of the hip joint: a hypothesis for etiology of sports hernia. Muscles Ligaments Tendons J 2015;5:29-32.

3. Strosberg DS, Ellis TJ, Renton DB. The role of femoroacetabular impingement in core muscle injury/ athletic pubalgia: diagnosis and management. Front Surg 2016;3:6.

4. Comin J, Obaid H, Lammers G, et al. Radiofrequency denervation of the inguinal ligament for the treatment of ‘Sportsman’s Hernia’: a pilot study. Br J Sports Med 2013;47:380-6.

5. Draovitch P, Edelstein J, Kelly BT. The layer concept: utilization in determining the pain generators, pathology and how structure determines treatment. Curr Rev Musculoskelet Med 2012;5:1-8.

6. Litwin DE, Sneider EB, McEnaney PM, et al. Athletic pubalgia (sports hernia). Clin Sports Med 2011;30:417-34.

7. Kachingwe AF, Grech S. Proposed algorithm for the management of athletes with athletic pubalgia (sports hernia): a case series. J Orthop Sports Phys Ther 2008;38:768-81.

The content shared in the Health Literacy Hub website is provided for informational purposes only and it is not intended to replace advice, diagnosis, or treatment offered by qualified medical professionals in your State or Country. Readers are encouraged to confirm the information provided with other sources, and to seek the advice of a qualified medical practitioner with any question they may have regarding their health. The Health Literacy Hub is not liable for any direct or indirect consequence arising from the application of the material provided.

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