Spondylolisthesis (vertebral displacement)

General information about spondylolisthesis

The spinal column consists of 33-34 vertebrae. The front and back surfaces of the vertebrae lie on top of each other in a straight line. Certain medical conditions can cause the vertebrae in a particular area of the spine to move forward or backward, disrupting the straight line. This condition is referred to in medicine as spondylolisthesis. It is formed by combining two words: spondylo – vertebra and listezis – displacement. It is popularly called “spinal dislocation”.

Causes

There are many identified causes that can lead to vertebral dislocation. These include: spondylolysis since birth; degenerative changes that are associated with age; trauma and other causes. Everyone can fall in childhood, and this is known to result in vertebral displacement. Especially in menopausal women and men with osteoporosis, vertebral misalignment becomes active and progressive.

Symptoms

Vertebral displacement leads to a decrease in the opening of the spinal canal, and thus contributes to compression of the dura mater and nerve roots. At this time, there is difficulty standing, fatigue when moving, back pain, and stiffness (numbness) in the back. Because of the compression of the nerves in the displaced spinal canal, patients complain about abnormal sensations (sensitivity disorders) in the extremities, such as: numbness, burning, tingling, cooling, creeping goose bumps. There are also complaints of a decrease in the distance the patient can walk without feeling pain, as well as pain in the muscles of the thigh and lower leg.

The spinal canal narrows as a result of vertebral misalignment, leading to the development of “neurogenic claudication” symptoms. As a result, the patient experiences back pain, numbness, stiffness, and pain in the legs while walking. This makes patients want to bend forward and sit up. The reason for this is relative dilation of the spinal canal during these movements. The patient is then able to continue on his way. Over time, while walking, these processes are repeated. It is also very important to consider the distance the patient can walk. With vertebral dislocation at the beginning of the vertebrae, the patient can walk 500 meters, and as it progresses, the distance decreases to 100 meters or less.

Diagnosis

In order to diagnose spondylolisthesis – vertebral displacement, you need to be examined by an orthopedic traumatologist. At this time, you need to inform the doctor, about the complaints, the time of the beginning of the disease, etc. Based on the clinical findings, the doctor may ask the patient to undergo a radiological examination. For an initial diagnosis, a radiographic examination may be sufficient. However, MRI, CT scans and EMG (electromyography) may be required to determine the cause of the disease, to look in detail at the intervertebral discs, spinal ligaments and nerve elements. These diagnostic methods are performed after the initial examination by a physician.

In some cases vertebral misalignment may not be detected with standing x-rays. In this case, X-rays are taken in positions of full flexion and full extension (hyperextension). This dynamic examination can detect vertebral displacement as well as changes in the angle of displacement and clarify the phenomenon of vertebral displacement instability. Radiologic techniques are used to determine the prognosis and treatment of spondylolisthesis. Some of these methods are presented below:

The Meyerding classification

The classification is based on the degree of vertebral misalignment. A misalignment of the articular surfaces of the vertebrae relative to each other of less than 25% is classified as grade 1, grade 2 is 25-50% misalignment, grade 3 is 50-75% misalignment, and grade 4 is greater than 75% misalignment.

The figure shows the Meyerding classification

Computer tomography (CT)

Axial projection imaging is required to identify the pathology. Fractures of posterior spinal elements may not be detected during radiography. A CT scan should be used, but it is worth mentioning that a CT scan is not the only method to make the diagnosis.

MRI

Used to detect pathologies of intervertebral discs, ligaments, dura mater and spinal nerve roots. It is the main diagnostic method for stenosis of the spinal canal.

Treatment

Vertebral dislocation is a spinal condition that reduces the patient’s quality of life, affects the patient’s walking, and causes unbearable pain that causes the patient to wake up during sleep. Depending on the severity of the patient’s complaints and the results of clinical diagnostic methods, a particular method of treatment is chosen.

• Medication treatment and rest
• Use of a back brace – a lumbosacral corset with metal plates
• Physical therapy
• Epidural blockade or blockade of spinal nerve roots
• Laminectomy – decompression of compressed nerves and spinal cord
• Decompression and reduction of dislocated vertebrae with titanium screws

Risk factors that affect prognosis should be considered for treatment planning:

• Age: The younger the patient, the worse the prognosis. Recently, the degenerative type of spondylolisthesis is more common among patients who are 55 years old.
• Gender: Spondylolisthesis is more common among women.
• If the vertebrae are unstable, the degree of listhesis will increase.
• Ligament elasticity.
• High degree of vertebral misalignment (The Meyerding classification)
• The angle of displacement is greater than 40-50 degrees.
• Poor prognosis in the dysplastic type of spondylolisthesis.

Conservative treatment

Conservative treatment is used for grade 1 and 2 the Meyerding classification of spondylolisthesis. These patients have no neurological symptoms and the pain is mild. Nonsteroidal anti-inflammatory drugs and muscle relaxants are used for treatment. Physiotherapy, physical therapy, and informing patients about the course of the disease are very important in treatment.

Surgical treatment

After the diagnosis of a vertebral misalignment is made, it must be checked to see if it is stable. If the vertebrae are stable, these patients do not require surgery. However, if an unstable vertebral misalignment is diagnosed, surgical treatment is imperative. If not, the patient may have serious problems with walking, sexual dysfunction, and the acts of urination and defecation.

Patients who need surgical treatment need to have it done in time. If complications arise, even after surgery, it will take a long time to recover the lost functions.

Indications for surgery for vertebral dislocation:

• Pain syndrome that does not go away with conservative treatment.
• Occurrence of neurological disorders.
• More than 50% spinal misalignment (The Meyerding Type 3 and 4).
• Increasing degree of vertebral misalignment.
• Presence of vertebral instability.
• Occurrence of postural deformity.

The extent of surgical intervention can vary depending on the type and degree of spondylolisthesis. The surgical technique changes in the presence of neurologic disorders.

The main goal of surgical treatment is to decompress the spinal canal and the compressed nerves through a change in the vertebral arch (laminectomy). If the nerve root compression is the result of hypertrophy of the facet joints, a medial facetectomy is performed to relieve the pressure on the nerve roots. Vertebral fixation and reduction with titanium screws and pins is performed to prevent further progression of vertebral misalignment and symptoms of instability.

This process is called spondylolisthesis reduction with transpedicular fixation. The reduction is reproduced through surgery: TLIF (Transforaminal Interbody Lumbar Fusion), PLIF (Posterior Interbody Lumbar Fusion) and ALIF (Anterior Interbody Lumbar Fusion).