In order to get to know how safe laser disc surgery can be, we first have to understand a little bit about disc pathology.
Disc pathology occurs mainly in adulthood and can generate several degrees of pain. In some cases, pain becomes disabling, having an important impact on the quality of life. It can affect both at the family and work levels. Due to this, it carries an economic cost for companies and for the public health system. The most frequent and characteristic radicular pain is produced by the herniated discs. This pain appears with greater frequency in the lumbar region.
Protrusion and herniated disc
A disc protrusion consists of the bulging of the fibrous envelope that surrounds the intervertebral disc. A herniated disc consists of the exit of part of the nucleus pulposus through a crack in the fibrous envelope of the disc.
In herniation, there has been content leakage. In protrusion, there is only deformation of the envelope, without content leakage.
How do they appear?
Under normal conditions, the normal process of disc wear causes some of the fibres that constitute its fibrous shell to lose strength and elasticity. So, it can retract or split spontaneously. When that happens, some of the gelatinous contents of the disc or nucleus pulposus can protrude.
In some cases, the pressure inside the disc may exceed the resistance capacity of the fibres of the fibrous shell. So the part and a portion of the disc protrudes or becomes herniated. As the nucleus pulposus of the disc is of gelatinous consistency when the column leans forward the disc tends to move backwards, and vice versa. The back of the fibrous envelope is less resistant than the front, since it is a thinner third, so it is more common for protrusions and hernias to appear on the back of the disc. Thus, the most typical situation in which a herniated disc occurs is when the patient leans forward with the legs stretched, loads weight on his arms and lifts, increasing the pressure on the most posterior portion of the disc, until exceeds the resistance capacity of the fibrous envelope and disc herniation occurs.
However, this situation is the most typical, but not the most frequent. Most hernias are produced by the gradual process of wear of the fibrous envelope, and there are few in which there is a clear and unique trigger.
The treatment depends on the aetiology and there are different therapeutic options. They range from conservative to more or less invasive surgical interventions. Among the latter is nucleolysis or percutaneous disc decompression by laser (PLDD). It consists of the percutaneous approach of the intervertebral disc for performing the denaturation, by vaporization, of the nucleus pulposus using laser energy.
In the lumbar region, pain reduction has been observed in 60-89% of patients operated by PLDD. However, it is necessary to emphasize the high percentage of failure of the technique. It sometimes requires that up to 38% of successfully treated patients to be intervened again by conventional surgery. The failure due to the impossibility of performing the PLDD has been reported in several studies by 9%. In the cervical and thoracic location, an improvement of the symptoms is indicated between 54.5-83% at 24 months of follow-up.
Although PLDD is a minimally invasive treatment, it does not mean that complications cannot emerge. Studies of the lumbar region report the appearance of muscle spasm (7.7%), sacroiliac inflammation (4.5%), transient nerve root damage (5%), recurrences (1.5%) and discitis (1.2%). In addition, bleeding, bruising, new-onset root deficit and damage to the sigmoid artery have also been observed.