A herniated disc, also called disc herniation or disc protrusion is a problem of the spine that causes compression of the nerves, causing pain, weakness and loss of sensation in one of the members. The most common disc protrusions are the lumbar herniations and cervical hernias.
If you do not explain the anatomy of the spine and spinal cord, it is impossible to describe in a simple way what a herniated disc. This introduction may seem a little more complicated, but their understanding will make it much easier to understand the causes and disc herniation symptoms. Read this part calmly and follow the illustration for a better understanding.
Our spine is made up of several small stacked bones called vertebrae. We have 24 articulated vertebrae (the vertebrae of sacral region are fused), 7 in the cervical spine, thoracic spine in 12 and 5 in the lumbar spine. Each vertebra has a hole in the center, called the vertebral foramen . On the sides of each pair of vertebrae other hole formed called intervertebral foramen .
Inside the vertebral foramen the spinal cord passes, structure responsible for the transport of nerve stimuli between the brain and the rest of the body. The spinal cord is born in the brain and goes until the end of the column, having about 45 cm long. Along its path through the column, the marrow releases several segments, called nerve roots, which are prolongations that serve to innervate the body regions. For example, the nerve that innervates hand has its origin in one of these nerve roots leaving the spinal cord. In the division between each two vertebrae, a nerve root is launched bilaterally through the intervertebral foramen. In total, the release cord 31 pairs of nerve roots throughout the column, which will be responsible for the innervation of the entire body.
The nerve roots coming out of the cervical spine will lead to the nerves that innervate the neck, shoulders and upper limbs. The nerve roots that leave the thoracic spine will lead to the nerves that innervate the trunk. The nerve roots exiting the lumbar and sacral spine will lead to the nerves that innervate the pelvis and lower limbs.
As mentioned above, the vertebrae forming the spine being stacked one on top of another. Between one vertebra and another for a cartilaginous structure, rubbery consistency, disk-shaped, called intervertebral disc. The intervertebral disc functions as a buffer or cushion, which aims to reduce the friction between one vertebra and another, facilitating the work of the column to move and support the body's weight.
Well, we made the necessary explanations about the basic anatomy of the spine, let's talk about herniated disc itself.
Hernia is the word used to describe the projection or protrusion of a given structure through an orifice or channel. A herniated disc occurs when a portion of the intervertebral disc protrudes through the intervertebral foramen or toward the spinal cord and can cause compression of the nerve roots.
The intervertebral disc is composed of an outer, rigid region, called the annulus fibrosus, and a central region composed of a gelatinous material, called the nucleus pulposus. The intervertebral disc is pliable and functions as a cushioning spring, being able to compress when there is weight on the spine and relax when the column is at rest, without receiving any weight.
When the intervertebral disc is exposed to a chronic wrong posture of the spine, repetitive movements, excessive load or trauma, it may suffer wear of the annulus fibrosus, causing a fissure through which the nucleus pulposus may herniate, pushing part of the disc toward one of the nerve roots. If the disc herniation enough to compress the nerve root, the patient will present the characteristic symptoms of disc herniation.
Most herniations the lumbar spine appears, which is the region of the column that has just having to support more weight and undergoes more stress throughout life. Second come the cervical spine disk herniations. Hernias of the thoracic spine are rare.
As we age, the intervertebral disc will become increasingly less flexible and elastic, getting exposed to cracks and breakage. Most disc protrusions occurs in persons over 35 years.
Among the main risk factors for the development of a disc herniation, include:
Jobs that require carrying excessive weights.
Making weight without proper guidance, overloading the column.
Raise the floor weights forcing the column (the right is not to bend the column to pick up something from the ground, but to squat to lift it).
Traumas back.
Poor posture.
Jobs that require repetitive movements of the spine.
In most cases, the hernia does not arise acutely. It is often a stressful process and disk repetitive injury. Usually, except for cases of hernias that arise after trauma or falls, patients do not remember a specific event that triggered the symptoms. The pain can come on suddenly at rest.
The herniated disc itself does not hurt. If the intervertebral disc is herniating, but there is no significant compression of adjacent nerve root, the patient may not have any symptoms.
Similarly, when symptoms, they may be mild, moderate or severe and incapacitating, depending on the degree of nerve root injury. The compression and nerve root injury is called radiculopathy.
The most common symptoms of herniated disk are pain, loss of sensation, tingling, and weakness in one of the members.
The location of the symptoms depends on the spinal region with a herniated disc. Let's quote some of the most common presentations.
Symptoms of Lumbar and sacral hernia
The most common disc herniation occurs in the 5th lumbar vertebra (L5). Its clinical picture is usually of low back pain, radiating throughout the lateral region of one leg. Weakness in the legs is also very characteristic. The patient may have difficulty performing movements such as dorsiflexion of the foot, toe extension, inversion and eversion of the foot. loss of sensation in the lateral portion of the leg and foot can also occur.
The herniated disc vertebrae L2, L3 and L4 are also common and have similar symptoms each other. The picture is of low back pain radiating to the front of the thigh to the knee. There may be weakness for knee extension and hip flexion. The loss of sensitivity often occurs in the anterior thigh portion and the inner face of the calf down to the arch of the foot.
The hernia of the first sacral vertebra (S1) can cause sciatica (this type of pain may also occur with L5 or L4 compression), characterized by lumbar and hip, which irradiates the rear portion and / or lateral thigh and may go to the heel. Weakness for leg extension and flexion of the fingers may be present, as well as loss of sensation in the posterior region of the lower limb.
Symptoms of cervical hernia
The most common cervical hernias occur between the 5th, 6th and 7th vertebrae (C5, C6 and C7).
Hernias C5 often cause weakness and pain in the muscles of the neck, shoulder and arm start. It can also be loss of in the armpit region.
The herniated C6 is the most frequent cervical hernia, may cause weakness and pain in the muscles of the neck, shoulder and arm, affecting biceps and forearm. It can also be loss of the lateral aspect of the forearm to the thumb and index finger.
The herniated C7 can cause pain in the neck muscles, shoulder, middle finger and hand. The weakness typically occurs in the triceps muscle. It can also arise loss of sensation in the triceps area, radiating hand and index and middle fingers.
In most cases, physical examination and medical history are sufficient for the diagnosis of a herniated disc. If the neurologist want to prove the existence of hernia or rule out other causes of radiculopathy, some tests may be ordered. Among the most common are computed tomography and magnetic resonance imaging.
Conservative treatment with rest, physical therapy, warm compresses, postural education and / or acupuncture relieves symptoms in over 90% of disc herniation patients. Most recovers, becoming able to return to their normal activities within one or two months. imaging tests, such as CT or MRI show that, with proper treatment, the disc protrusion shrinks over time, decreasing nerve root compression and causing improvement in symptoms.
Drugs for herniated disc
In general, common analgesics and anti-inflammatory and relieve the symptoms of radiculopathy. In more severe cases, stronger medications may be needed, such as Tramadol. Drugs that act on pain of neurological origin can also be useful, such as gabapentin, pregabalin, duloxetine or amitriptyline. Muscle relaxants or diazepam also help relieve pain. In some patients, the neurologist may indicate local injection with corticosteroids to reduce nerve inflammation.
Surgery for herniated disc
indicated in cases where the conservative treatment does not improve after 6 weeks when the muscular weakness becomes progressively worse or when pain and weakness are disabling.
The most common surgery is the removal of the herniated part of the disc, relieving nerve compression. In some cases the entire intervertebral disc to be removed and the two vertebrae are fused. Another option is failed disk removal and replacement with an artificial disc.
Minimally invasive techniques
There are several surgical techniques for herniated discs that are considered minimally invasive. Among them, percutaneous discectomy, endoscopic discectomy, discectomy Laser and Nucleoplasty with radio frequency.
Minimally invasive techniques involve smaller incisions and surgery with the aid of indirect viewing. Some of these procedures employ laser or radio frequency to dissolve parts of the disk.
Minimally invasive procedures have the potential advantage of a faster recovery when compared with open discectomy, which is the classic surgical technique.
