What is a hernia?

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I am looking around to write about What a hernia is. Let us Talk a little about the hernia. I am sure a lot of people here will love to read more about  Hernia.



A hernia is the protrusion of an organ or the fascia of an organ through the wall of the cavity that normally contains it.
Hernias can be classified according to their anatomical location:
Examples include:

• abdominal hernias
• diaphragmatic hernias and hiatal hernias (for example, paraesophageal hernia of the stomach)
• pelvic hernias, for example, obturator hernia
• anal hernias
• hernias of the nucleus pulposus of the intervertebral discs
• intracranial hernias
• Spigelian hernia

Each of the above hernias may be characterized by several aspects:

• congenital or acquired: congenital hernias occur prenatally or in the first year(s) of life, and are caused by a congenital defect, whereas acquired hernias develop later on in life. However, this may be on the basis of a locus minoris resistentiae (Lat. place of least resistance) that is congenital, but only becomes symptomatic later in life, when degeneration and increased stress (for example, increased abdominal pressure from coughing inCOPD) provoke the hernia.
• complete or incomplete: for example, the stomach may partially or completely herniate into the chest.
• internal or external: external ones herniate to the outside world, whereas internal hernias protrude from their normal compartment to another (for example, mesenteric hernias).
• intraparietal hernia: hernia that does not reach all the way to the subcutis, but only to the musculoaponeurotic layer. An example is a Spigelian hernia. Intraparietal hernias may produce less obvious bulging, and may be less easily detected on clinical examination.
• bilateral: in this case, simultaneous repair may be considered, sometimes even with a giant prosthetic reinforcement.
• irreducible (also known as incarcerated): the hernial contents cannot be returned to their normal site with simple manipulation.

If irreducible, hernias can develop several complications (hence, they can be complicated or uncomplicated):

• strangulation: pressure on the hernial contents may compromise blood supply (especially veins, with their low pressure, are sensitive, and venous congestion often results) and cause ischemia, and laternecrosis and gangrene, which may become fatal.
• obstruction: for example, when a part of the bowel herniates, bowel contents can no longer pass the obstruction. This results in cramps, and later on vomiting,ileus, absence of flatus and absence of defecation.
• dysfunction: another complication arises when the herniated organ itself, or surrounding organs, start to malfunction(for example, sliding hernia of the stomach causing heartburn,lumbar disc hernia causing sciatic nerve pain, etc.). 

Treatment
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It is generally advisable to repair hernias quickly in order to prevent complications such as organ dysfunction, gangrene, multiple organ dysfunction syndrome, and death. Most abdominal hernias can be surgically repaired, and recovery rarely requires long-term changes in lifestyle. Uncomplicated hernias are principally repaired by pushing back, or "reducing", the herniated tissue, and then mending the weakness in muscle tissue (an operation calledherniorrhaphy). If complications have occurred, the surgeon will check the viability of the herniated organ, and resect it if necessary.
Modern muscle reinforcement techniques involve synthetic materials (a mesh prosthesis) that avoid over-stretching of already weakened tissue (as in older, but still useful methods). The mesh is either placed over the defect (anterior repair) or more preferably under the defect (posterior repair). At times staples are used to keep the mesh in place. These mesh repair methods are often called "Tension Free" repairs because, unlike older traditional methods, muscle is not pulled together under tension.
Evidence based testing initially suggested that these Tension Free methods have the lowest percentage of recurrences and the fastest recovery period compared to older suture repair methods. However, prosthetic mesh usage seems to have a high incidence of infection with mesh usage becoming a study topic for the National Institutes of Health.

One study attempted to identify the factors related to mesh infections and found that compromised immune systems (such as diabetes) was a factor. Mesh has also become the subject of recalls and class action lawsuits.
Increasingly, some repairs are performed through laparoscopes.
Laparoscopic surgery is also referred to as "minimally invasive" surgery, which requires one or more small incisions for the camera and instruments to be inserted, as opposed to traditional "open" or "microscopic" surgery, which requires an incision large enough for the surgeon's hands to be inserted into the patient. The defensive and misleading term microscopic surgery refers to the magnifying devices used during open surgery.
Many patients are managed through day surgery centers, and are able to return to work within a week or two, while intensive activities are prohibited for a longer period. Patients who have their hernias repaired with mesh often recover in a number of days. Surgical complications have been estimated to be up to 10%, but most of them can be easily addressed. They include surgical site infections, nerve and blood vessel injuries, injury to nearby organs, and hernia recurrence.
Generally, the use of external devices to maintain reduction of the hernia without repairing the underlying defect (such as herniatrusses, trunks, belts, etc.), is not advised. Exceptions are uncomplicated incisional hernias that arise shortly after the operation (should only be operated after a few months), or inoperable patients.
It is essential that the hernia not be further irritated by carrying out strenuous labour.