Dural Sac: Definition, Structure, Compression, Tears and Injury Prevention

It is the protective membrane of the spinal cord, which is found around it.

To understand what constitutes this element of the human body, it must be considered inseparable from the structure of the spinal column .

The spine is the most important and vital organ in human beings that is very difficult to describe.

It includes a certain number of vertebrae interconnected by intervertebral joints, which form a whole.

Within the spinal column is the spinal cord in the so-called dural sac.

The dura

The dura is the outermost of the spinal meninges . It is a thick, fibroelastic membrane composed of collagen and elastin fibers that is a continuation of the cranial dura mater.

In its cephalic origin, it fuses with the periosteum of the skull at the foramen magnum, and continues circumferentially until its termination at approximately S2 in the adult.

Here it merges with the filum terminale and eventually the periosteum of the coccyx.

Laterally, it follows the roots of the spinal nerves to approximately the level of the intervertebral resources, where it mixes with the epineurium of the roots.

Structure of the dural sac

The dural sac is a structure of the spinal cord. The main purpose of this bag is to protect the spinal cord from various kinds of influences on it, and the protection in turn of the dural sac is the spinal column.

That is why this element cannot be considered separately from the device for the spine.

Surrounding the spinal cord are three layers in the following sequence: solid, arachnoid, and soft.

It is a tight, solid sac filled with cerebrospinal fluid – the fluid reservoir of the spinal cord.

Due to the fact that the length of the spinal canal is greater than the length of the spinal cord, the nerve roots that move in the cerebrospinal fluid are not limited.

The dural sac starts from the large hole in the back and ends around 2 or 3 sacral vertebrae.

This dural sac has cone-shaped projections that, penetrating the openings between the vertebrae, envelop the roots of the nerve endings.

A large number of fibrous bundles directed at the posterior longitudinal ligament strengthens the bursa.

A slit-shaped subdural space, starting from the same space in the skull and ending in the sacrum, separates the hard shell from the spiders.

The description of the structure and location of the dural sac is quite complex, even from a more complex definition by different membranes of the spinal cord and separating them is impossible, like most of the organs of the body, since they are closely intertwined.

Another very important point is that the solid covering has no nerve endings and cannot radiate.

But due to the fact that they are closely related, when some displacement occurs, you may experience severe pain that usually causes compression.

Dural sac compression

If an image of the spine and dural sac is considered, it is clear that any deformation of the spine can affect the dural sac.

In other words, such pathologies of the spine, such as low back pain and herniated disc, can be triggered by compression of the dural sac.

These are the diseases in which the matter of the spinal cord is compressed due to deformation of the vertebrae and intervertebral discs.

Osteochondrosis is characterized by degenerative-dystrophic lesions of the elements of the spine.

Suffering from degenerative disc diseases becomes the cause of spinal disc herniation that occurs when there is displacement of the intervertebral discs.

This phenomenon often causes compression of the dural sac, due to which the skewed disc begins to tighten.

The person in this situation experiences very severe pain and their quality of life is reduced.

Degenerative disc disease is believed to be the cause of herniated discs due to deformation.

Dural sac tears

A dura tear is a complication of spinal surgery in which the surgeon’s instrument cuts the thin covering over the spinal cord (called the dura).

Dural sac tears can lead to cerebrospinal fluid leakage, meningitis, nerve problems, and more serious conditions.

Dural tears tend to occur more frequently with revision spine surgery, spinal surgery, spinal fusion, and finally multi-level decompression (for spinal stenosis).

Disc surgery and single-level decompression surgeries tend to produce the fewest dural tears, relatively speaking.

One of the symptoms of a dural sac tear is a clear discharge of fluid from a surgical wound.

You may also experience position-related headaches that are worse when you stand up and are relieved when you lie down.

Other symptoms include visual changes, nausea, vomiting, or dizziness,

If not treated quickly and properly, a cerebrospinal fluid leak can negatively affect your health. Therefore, symptoms such as those mentioned above require immediate medical attention.

The doctor usually catches a dural tear during surgery and it is treated right then and there.

Treatments for dural tears include bed rest, drainage, and if the leaks continue, it’s surgery. Surgery for a dural tear is very similar to plugging a hole in a tire.

Risk factor’s

Pre-existing conditions and / or deformities can increase your risk for dural sac injuries.

It mainly affects people with chronic diseases and people with these conditions:

  • They are overweight.
  • They lead a sedentary lifestyle.
  • They have an office job (sitting a lot of time) and they often experience stress.
  • Have bad posture
  • They wear uncomfortable or inappropriate footwear.

For example, steroid use, diabetes, or smoking increase risk.

The same is true if you have certain spinal problems, namely: spondylolisthesis, stenosis, scoliosis, or kyphosis.

Prevention of problems with the spine

For the health of the spine it is necessary to monitor it from childhood. And the main way to maintain your well-being is proper nutrition and an active lifestyle.

In addition, the food should be not only without the use of fried and smoked foods, but also with a high content of vitamins and minerals and which should be instilled in children from an early age.

If in childhood the child develops improper posture, in old age he will suffer from back pain.

Most often, osteochondrosis occurs at a more mature age, especially in women after pregnancy and childbirth, when the body experiences an increased load on the spine before and after birth.

In the end, due to permanent loads, there is some deformation of certain elements of the spinal column.

For the prevention of diseases of the spine, a lot of rest is needed.

And at the same time you need a lot of exercise to maintain the health of the spine, massages and moderate exercises should be performed at least periodically to strengthen the muscles, not only the back, but also the whole body.

In addition, there are certain rules for the preservation of the health of the spine (nutrition, sleep and rest, exercises with different degrees of difficulty).

You should sleep better on your back, walk with your hips and back straight and your stomach plunged, sit up straight, never pull, or push your body forward to get up.

These simple tips will help you fight many diseases of the spine.

Dural sac and anesthesia

The dural sac and arachnoid matter are closely adhered to their inner surface, and are a barrier to drug migration into and out of the cerebrospinal fluid during epidural anesthesia.

The termination of the sac well below the medullary cone (classically found at L1 in the adult) also provides a degree of safety when performing spinal anesthesia.

This offers the anesthesiologist multiple spinal levels for intrathecal drug delivery with low risk of direct spinal cord trauma.

There are age-related anatomical variations in the location of the caudal end of the dural sac that can affect neuraxial anesthesia.

During early development in the womb, the spinal cord exists throughout the spinal canal.

The differential growth of the vertebrae compared to the nerves and the umbilical cord represents a relative ascension of the umbilical cord within the canal over time.

At birth, the sac ends at S3 or S4, with the medullary cone ending at the L3 or L4 level.

It is not until about one year of age that anatomical relationships resemble those of the adult.