Introduction
Anatomically, the groin represents a clearly defined area, which is located in the lower and lateral area of the abdominal wall. The triangular area is bordered centrally by the upper edge of the pelvis, the so-called “symphysis” above the pubic region and laterally by the two iliac crests, which are well palpable as bone points of the lateral pelvis. The abdominal wall is composed of many superimposed layers through which important anatomical pathways run. The inguinal canal runs through the abdominal wall and contains blood vessels, lymphatic channels and, in men, the spermatic cord. The layers of the abdominal wall protect the important anatomical structures from injury.
Anatomy of the groin
In some other parts of the groin, structures pass through the muscle walls to reach the pubic region and the legs. For this purpose there are small holes in the connective tissue and muscular layers of the abdominal wall, also called “lacunae”. Below the skin and subcutaneous fatty tissue there is a superficial cover of connective tissue.
This surrounds 4 large muscle layers, which enable the stability and movement of the trunk. Its most prominent representative is the “Musculus rectus abdominis”, the relief of which is clearly visible on the middle abdominal wall of trained persons as a so-called “six-pack”. Beneath a deeper layer of connective tissue, the abdominal cavity then follows, which mainly contains the intestinal loops.
The many anatomical pathways and openings in the abdominal wall increase the risk of injury. Especially inguinal hernias are a frequent complication. They mainly occur at the weak points of the abdominal wall, where blood vessels and nerves pass through, but also at the inguinal canal.
Important anatomical pathways pass through the inguinal region at various points. These include arterial and venous blood vessels, lymph channels with associated lymph nodes, nerves that originate mainly from the lowest sections of the spinal cord, ligament structures and the male spermatic cord. The ducts are surrounded by layers of the abdominal wall, which consist of muscular and connective tissue.
These form channels or openings around the vessels. An important example is the inguinal channel. It runs through the front abdominal wall diagonally from the rear, lateral pelvis, to the front, centrally into the pubic region.
In men, it mainly contains the spermatic cord that leads from the testicles to the urethra. In men and women it also contains blood vessels and nerves that supply the pubic region. The lower edge of the groin region is limited by the inguinal ligament which is present on both sides.
It stretches between the iliac crest of the respective side and the pubic symphysis. Below the inguinal ligament, several major blood vessels and nerves run, some of which run into the pubic region and most of which run into the legs to supply the structures there. The most important blood vessels of the leg pass through the so-called “lacuna vasorum”.
Large lymph nodes can also be found there, below the inguinal ligament. If there is too much pressure on the groin region, for example by tightly tied belts, sensitive nerves can be squeezed. Frequently, a tingling sensation occurs in the front thigh.
Various complications can arise due to the openings for the numerous vessels in the groin. Especially inguinal hernias are a common problem in this region. If a nerve is pinched in the region of the groin, numbness and discomfort can occur in this area as well as on the front or side of the thigh.
If a nerve is pinched, severe burning pain can occur. The symptoms depend on the type of nerve. There are nerves that are responsible for muscle movements and there are nerves that are responsible for the sensitivity and the feeling of touch of a skin area.
Depending on which nerve is pinched, paralysis or numbness and tingling may occur. Pinching of a nerve under the inguinal ligament can occur due to pressure or traction forces in the nerve path. Causes can be overweight, pregnancy or the wearing of too tight clothing (belt).
In the inguinal region, especially below the inguinal ligament, there are large accumulations of lymph nodes, which contain the lymph of the legs and partly of the pubic region. The lymph nodes can often be palpated as small nodules even in healthy individuals. The lymph is collected throughout the body and transported via lymph channels to the lymph nodes.
These filter the entire lymph fluid for harmful pathogens and foreign substances before it is returned to the bloodstream via a large internal circulation.Lymph nodes can become enlarged, which can have a number of different causes. Local accumulations of pathogens can cause the lymph nodes to become inflamed. In the groin, they can then be palpated in a significantly enlarged form and often the touch is painful.
A painful enlargement often indicates bacterial inflammation. If the lymph node is enlarged but not painful, this may be an indication of a disease of the lymphatic system, for example a form of lymph cancer. If the patient notices a thickened lymph node, this is often no cause for concern, but the cause should be clarified by a doctor.
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