With the passage of time, in almost all human beings, probably due to the overload that the lumbar spine endures due to standing upright, chemical changes occur inside the discs, which lead to their dehydration. Dehydration alters the properties of the hydraulic mechanism of the healthy disc. When the disc loses its shock-absorbing function, the load distribution is transferred to the vertebral joints and ligaments, which may react by hypertrophying and narrowing the canal through which the nerve roots run. In addition, there are mechanical alterations in the mobility between the vertebrae.
The first image is a drawing in which different degenerative manifestations that produce radicular compression are represented. The second image is an MRI of a case with degenerative problems and herniations in the last two lumbar levels.
These morphological and functional manifestations define “osteoarthritis of the lumbar spine”. The irritated discs and joints become inflamed and produce lumbar pain, better known as lumbago. Traumatology specialists explain that when the nerve roots are irritated, sciatic pain or sciatica is produced.
When is it necessary to operate?
In most cases there is no need to follow any surgical treatment because the pain disappears with conservative treatments. It is therefore advisable to wait some time (at least three months) before deciding to have surgery. However, in many patients the pain persists over time and surgery is necessary.
The decision to go to the operating room is made with “common sense”, like other important decisions in life: taking into account the pros and cons. Above all, future expectations and quality of life must be considered. The decision is made when the symptoms are sufficiently important and the patient knows that he/she will not improve if he/she does not have surgery.
Objectives of surgical treatment of lumbar radiculopathy:
Surgery has two objectives:
- Decompression. To decompress the nerve roots, laminectomies, facetectomies, flavectomies, foraminotomies or disc removal (discectomy) are performed. The purpose of these procedures is to free the roots from compression (Figure 2).
- Fusion or arthrodesis. Frequently, in addition to decompression, fusion is necessary. Fusion is the most commonly used method to stabilize the lumbar levels. By means of this procedure we immobilize the vertebral levels whose mobility is diseased and causes pain. For this purpose, we place implants in the vertebrae and bone graft associated with calcic osteoconductive substances.
Thanks to the technological development of the last decade, both for decompression and fusion, we have considerably reduced the surgical aggressiveness, making less invasive surgeries by means of special separators, which allow much smaller incisions to be made.