This is a type of surgery used in treating spinal stenosis, a condition that occurs due to the narrowing of space between the spinal vertebrae. In order to have a better understanding about spinal stenosis surgery, it is important to have a clear idea about the conditions which lead to this problem.
The anatomy of the spine
The spine is medically referred as the 'vertebral column' and stretches from the bottom of the skull to the back of the pelvis. Unlike other bones in the body which are stiff and brittle, the spine needs to be flexible in order to allow twisting from side to side and bending forward and backwards. The vertebrae are also hollow and consists of a spinal cavity through which the spinal cord passes.
The spine is made up of 33 individual bones called vertebrae instead of a continuous column to function efficiently. The first 7 form the cervical spine (neck) and the rest are aligned at the back or the torso. The last 4 vertebrae are fused to form the coccyx and the 4 vertebrae at the lower back are fused to form the sacrum. Because of this, the vertebral column is often considered to have 26 vertebrae rather than 33.
To keep all these ligaments held together, a cartilage by the name of intervertebral disc ensures that the vertebrae are held together while allowing slight movement. The presence of holes in the intervertebral disc allow the spinal nerves to leave the spinal cord and reach various parts of the body to perform their function.
Development of spinal stenosis
Given that the intervertebral discs are just a form of ligaments, they are vulnerable to wear and tear just like any other cartilage in the bone. The rate at which the intervertebral discs wear off will vary from person to person. However, this process usually happens over time and is most common among those above 65 years of age. Few other factors such as trauma to the vertebrae, improper posture or genetics can speed up this process and cause the intervertebral discs to wear off faster.
Since these discs are responsible in providing room for the spinal nerves to leave the spinal cord, their wear may lead to these nerves being compressed. The space between a pair of vertebrae which are separated by the intervertebral disc will become narrow and the vertebrae will press upon the spinal nerve passing between them.
Symptoms of lumbar spinal stenosis
Spinal nerves which emanate from the spinal cord and reach various parts of the body provide both motor and sensory functions. Therefore, their compression by spinal vertebrae can cause various symptoms. These symptoms depend on the affected region of the vertebral column. The two bottom areas of the cervical column, the coccyx and the sacrum are fused and do not get damaged often. But the cervical spine and lumbar regions of the vertebral column are affected mostly due to their shape and motion. Some of these symptoms include:
Lumbar spinal stenosis
The lumbar spine supplies nerves to the lower back, pelvic region and the legs. Some of the symptoms of damage to this region include:
- weakness and numbness especially during physical activity
- pain radiating from the lower back to the legs
- tingling sensation
This refers to the pinching of spinal cord in the neck. Symptoms of damage include:
- pain radiating from the neck to the shoulders and arms
- pain in the neck and jaw
- weakness in the arms
Symptoms do not show all the time. Some people who may have spinal stenosis may not experience any of these symptoms.
Diagnosis and management of spinal stenosis
The symptoms of spinal stenosis don’t automatically lead to a positive diagnosis of the condition because various other medical conditions can cause similar symptoms. In order to determine this, various other tests such as X-rays, MRI and CAT scans must be conducted to identify the source of problem and the extent of damage.
If the problem is determined to be spinal stenosis, surgery is not the first recommended measure. In that case, various non-surgical measures are attempted such as:
- physical therapy
- rest and limiting physical activity
- medication to reduce pain and inflammation if any
- a neck brace for cervical stenosis
Lumbar cervical stenosis surgery
If the symptoms are too severe which causes the individual to become incapacitated, surgery may be recommended. There are several intervention methods that could be made through this form of surgery. They are:
If two vertebrae are extensively damaged, they may be fused together to limit movement since it is the movements that increase damage and compress the spinal nerves.
If the spinal stenosis is caused by damage to one vertebra, for example, due to trauma or injury, this damaged vertebra can form a bone spur which presses upon the spinal nerve. This form of cervical stenosis surgery merely removes just the damaged section of the vertebrae to prevent it from pressing on the nerve.
Upon identifying the location where the vertebrae are not too severely damaged, a section of each vertebra can be removed at the point where the nerve leaves the intervertebral disc thus allowing the nerve to leave without pressure.
This form of surgery is very effective with as much as 80% success rate in relief from symptoms of spinal stenosis permanently. In addition, the individual is able to resume intense physical activities because the surgery is somewhat minimal.
Instead of attempting to repair the damaged vertebra, the entire vertebra can be replaced with an artificial facet joint. However, this method of lumbar spinal surgery is not yet approved and it is hardly performed.
This is a device which is inserted between individual vertebrae that are compressing a nerve. When inserted, it keeps the vertebrae apart and away from the spinal nerve, effectively reducing the symptoms of lumbar spinal stenosis. This is also a new type of procedure which is being made available to the public recently.
What to expect during the surgery?
The entire surgery is done while the individual is unconscious and under general anesthesia. Since it is a delicate surgery, it may take at least an hour depending on the adopted procedure.
The patient may have to stay in the hospital for a few days depending on the extent of the surgery. Even after being discharged, they have to avoid engaging in physical activities for at least a few weeks.