Schmorl hernia

Generality

Schmorl 's hernia is a particular type of herniated intervertebral disc, characterized by the vertical protrusion of the nucleus pulposus and of the surrounding fibrous ring.

According to the most reliable theories, it seems that to cause Schmorl's hernia may be traumas at the base of the spine, incorrect lifting of heavy objects, some congenital diseases of the spine and some idiopathic spine anomalies.

Schmorl's hernia is often a condition of little relevance from a clinical point of view; in most cases, in fact, it is asymptomatic and does not produce serious consequences.

Radiological examinations, such as vertebral column X-rays or nuclear magnetic resonance of the spine, are essential to identify a Schmorl hernia and study its characteristics.

Schmorl's hernia requires treatment only in those rare circumstances in which it is symptomatic.

The treatment in question may be conservative (less severe symptomatic cases) or surgical (more severe symptomatic cases).

Short revision of the spine

Carrier axis of the body, the spine or spine is a bone structure of about 70 centimeters (in the adult human being), which includes 33-34 irregular bones ; stacked on each other and joined together by means of so - called intervertebral discs, these irregular bones are the known vertebrae .

VERTEBRAE

In a generic vertebra three characteristic elements can be recognized, which are:

The vertebral body, in anterior position;
The vertebral arch, in posterior position;
The vertebral hole . It is the opening resulting from the particular arrangement of the vertebral arch with respect to the vertebral body.
- The set of vertebral holes of all the vertebrae constitutes the so-called spinal canal ; in the spinal canal houses the spinal cord .

INTERVERTEBRAL DISCS

An intervertebral disc is a circular fibrocartilaginous structure, which contains within it a gelatinous substance, called the pulpy nucleus, and the cartilaginous tissue that surrounds the aforementioned nucleus pulposus, ie the so-called fibrous ring .

In addition to providing for the conjunction of the adjacent vertebrae, the intervertebral discs have the task of absorbing, by means of the pulpy nucleus, the shocks and loads that weigh on the spine. In other words, with their particular content, the intervertebral discs act as shock-absorbing bearings.

What is Schmorl's hernia?

Schmorl's hernia is the name that, in the medical field, indicates the protrusion of the contents of an intervertebral disc (nucleus pulposus and fibrous ring) towards the vertebral body of one of the two adjacent vertebrae (therefore, it is a vertical protrusion, directed towards the upper vertebra or towards the lower vertebra).

As will be seen later, the presence of a Schmorl hernia has only a few clinical relevance in rare cases.

It is an example of a herniated intervertebral disc

Schmorl's hernia is a particular example of a herniated intervertebral disc .

The herniated intervertebral disc is a fairly common vertebral column disease, which is characterized by the exit of the nucleus pulposus and the fibrous ring from their natural site (ie the intervertebral disc), in the direction of the nervous structures that run laterally to the column vertebral (spinal roots and nerves) or in the direction of the vertebral bodies located above or below (which is what happens in the case of Schmorl's hernia).

Schmorl's hernia is a vertical hernia of the intervertebral disc .

The verticality of the protrusion is the characteristic that distinguishes Schmorl's hernia from the lateral hernias of the intervertebral disc, in which the protrusion compresses the nervous structures located on the sides of the vertebral column (spinal roots and nerves).

Where is it based?

Most cases of Schmorl's hernia have, by location, the thoracic tract or the lumbar spine.

However, it should be pointed out that episodes of Schmorl's hernia can occur in any section of the spine, and therefore also in the cervical and sacral areas.

Epidemiology

Schmorl's hernia seems to be a fairly widespread phenomenon; according to some statistical research, in fact, it would affect about 30% of the general population.

Synonyms

Schmorl's hernia is also known as Schmorl's nodule, Schmorl's intraspongius hernia and Schmorl's intraspongient nodule .

Origin of the name

Schmorl's hernia owes its name to the first person who described it in detail: the German pathologist Christian Georg Schmorl, who lived between 1861 and 1932.

Causes

The causes of Schmorl's hernia are still not entirely clear; on the subject, however, there are several theories. According to these theories, Schmorl's hernia could be due to:

Trauma at the base of the vertebral column that forces the complex of pulpy nuclei and fibrous rings upwards, ie towards the overlying vertebra. This type of trauma occurs on violent falls on the buttocks (eg: falling from the skis) and on the occasion of jumps from high positions (eg: the landing of gymnasts at the end of certain exercises).
The incorrect and repeated lifting of heavy objects over time . Especially at a young age, this wrong behavior excessively overloads the spine, to the point of altering the normal anatomy of the intervertebral discs.
Congenital disorders of the spine, such as Scheuermann's disease (also known as juvenile osteochondritis of the dorsal vertebrae or juvenile idiopathic kyphosis).
Idiopathic abnormalities of the spine . In medicine, an illness or an anomaly that arises for unknown or unrecognizable reasons is called "idiopathic".

Risk factors

Among the risk factors of Schmorl's hernia are:

Advanced age. Statistics in hand, patients with a Schmorl hernia are mostly people who tend to old age;
Work activities in which heavy objects are to be lifted;
Falls on the buttocks;
The practice at high levels of artistic gymnastics;
The presence of some congenital diseases of the spine (eg: Scheuermann's disease);
Vitamin D deficiency. Some experts have strong doubts about the real influence of this circumstance; consequently, the debate on this is open.

Symptoms and complications

Schmorl's hernia is more often an asymptomatic (ie symptomless) than symptomatic presence (ie responsible for disorders); furthermore, its degeneration in complications is decidedly unusual.

Symptomatic Schmorl hernia: what symptoms does it cause?

In those rare circumstances in which it is symptomatic, Schmorl's hernia is responsible for an annoying back pain, which can sometimes be very intense, debilitating and particularly long-lasting (can last several months).

Unlike the pain induced by the lateral hernias of the intervertebral disc (those that crush the roots and the extensions of the spinal nerve roots), Schmorl's hernia pain does not affect the lower limbs.

What is the cause of the pain?

Currently, it is not clear on what the pain related to Schmorl's hernias depends and why this symptom concerns only certain patients.

According to some theories - not yet completely verified - the aforementioned pain would have an inflammatory nature and could derive from two different circumstances:

The presence of a protrusion such that the nucleus pulposus and the fibrous ring are able to come into contact and compress the spinal cord of the vertebra towards which they are oriented;
The presence of a protrusion such as to have caused, over time, the inflammation and necrosis of the vertebral body with which the nucleus pulposus and the fibrous ring came into contact.

Complications of Schmorl's hernia

The most severe Schmorl's hernia episodes are responsible for such intense back pain that it is difficult, if not impossible, to carry out the most normal daily activities.

Moreover, scientific studies have shown that, due to a severe hernia of Schmorl, the risk of vertebral fracture increases by about 10% (NB: clearly, the vertebra for which the risk of fracture increases is that on which the nucleus pulposus act and fibrous ring).

Diagnosis

Due to the absence of a clear symptomatology, Schmorl's hernia is a difficult condition to diagnose; again, for the same reason, its identification is, in most cases, completely random, the result of diagnostic tests performed for other reasons.

How to locate a Schmorl hernia?

To identify a Schmorl hernia, radiological examinations are required such as X-rays, CT or nuclear magnetic resonance, all obviously related to the spine.

Wanting to be more precise, of the three aforementioned radiological examinations, X-rays represent the diagnostic method that provides less detail and can give false negatives (ie Schmorl's hernia is present, but does not result from the test).

To make the diagnosis of a Schmorl hernia easier is, without a doubt, the presence of a painful symptomatology; back pain, in fact, despite being a non-specific symptom, is a clear sign of something abnormal / pathological.

Curiosity: how are symptomatic Schmorl hernias to radiological images?

On radiological images, symptomatic Schmorl hernias are generally larger than non-symptomatic Schmorl hernias.

This tendency has led doctors to think that the symptoms of Schmorl's nodule are related in some way to the dimensions of the protrusion.

Therapy

Schmorl's hernia requires therapy only when it is symptomatic; in the absence of symptoms, in fact, it is a completely harmless condition and for which it makes no sense to plan a cure.

Therapy for symptomatic cases of Schmorl's hernia may be conservative or surgical .

Generally, conservative therapy is the basic (or first-line) treatment, while surgery is the extreme treatment, adopted only and exclusively when the aforementioned conservative therapy has proven to be ineffective or poorly effective.

Conservative therapy: what does it consist of?

Schmorl's hernia conservative therapy includes:

Pharmacological treatments based on anti - inflammatories, such as paracetamol or ibuprofen (an NSAID);
Physiotherapy . The physiotherapy treatment consists of a rehabilitation program for strengthening the back muscles and improving trunk flexibility;
The application of ice on the painful area of the back . The ice has a remarkable anti-inflammatory power, which however many underestimate;
Chiropractic sessions. Chiropractic is a practice of alternative medicine, which makes the manipulation of the spine its pivotal point;
Use of a lumbar or thoracolumbar brace .

Surgical therapy: what does it consist of?

There are two possible surgical treatments for the treatment of Schmorl's hernia: percutaneous vertebroplasty surgery and the intervention of kyphoplasty .

Vertebroplasty and kyphoplasty are two rather delicate operations, which both involve, albeit with different techniques, the remodeling of the vertebra which undergoes invasion by the nucleus pulposus and fibrous ring.

Prognosis

If the prognosis for the asymptomatic episodes of Schmorl's hernia is excellent, the same cannot be said for the symptomatic cases of Schmorl's hernia; in these latter circumstances, in fact, the disease of the vertebral column in question can sometimes be a serious problem, which requires many months of treatment, before being cured.