Basis, indications and risk: Basis, indications and risk

Treatments Basis, indications and risk Patient information Postural hygiene Exercise Maintaining level of Activity Bed rest Pharmacological therapy Neuroreflexotherapy (NRT) Spinal surgery Surgery for Pain and Pain Clinics Vertebral manipulation Behavioral treatment Epidural injections Facet joint infections Trigger point and ligament infections Rhizotomy Corsets and lumbar belts Traction Physical therapy/physiotherapy Electromyografic Feedback TENS: Transcutaneous electrical Nerve Stimulation Shoe insoles and shoe lifts Acupunture Recommended treatments

Spinal surgery

Objetive

To correct structural anomalies of the spine.

Theoretical basis

To correct the structural anomaly that causes back pain. For example, when a progressive spondylolisthesis compresses nerve structures, placing the vertebra in its correct location and securing it there avoids compression and progression.

Evidence of efficacy

Some evaluation methods, although scientifically optimal, cannot be applied to surgery due to their characteristics. For example, it is not acceptable to postpone surgery in a group of patients who need to be operated on according to the accepted current criteria, with the sole aim of confirming that those who are not operated on become paralyzed.

But there are studies on criteria to be followed in considering the appropriateness of surgery. Some of the existing evidence-based recommendations consider these studies as well as experts' criteria for establishing the recommendations below. Although criteria to operate for each type of structural spinal anomaly are mentioned in the corresponding section, the general criterion is to operate only in case of proven significant spinal cord or nerve root compression of more than one month's duration, and when the structural anomaly is in fact the cause of pain.

Risks and contraindications

Some of the existing evidence based recommendations establish that risk of infection or hemorrhage during the first intervertebral disc surgery is less than 1%, although this risk increases greatly with older patients or when it is not the first disc operation.

The real risk appears when the operation yields no satisfactory outcome. Some of the existing evidence based recommendations establish that, among surgical patients with disc herniation without evident signs of nerve compression on physical examination or by electromyogram, less than 40% obtain satisfactory results. Available scientific studies show that the main cause of surgical failure comes from operating on patients who should not have undergone surgery. The stricter the selection of patients referred for surgery, the better the results.

Postoperative fibrosis is another surgical risk. It is accepted that the less aggressive the operation, with less bleeding during surgery, the smaller the risk of onset of fibrosis.

Surgery requires a minimum status of good general health. Some general diseases (cardiac, pulmonary or metabolic) can impede surgery.

Main surgical techniques

• Laminotomy:
  • It is a technique for operating on disc herniations. It consists of reaching the nerve root and the herniated disc, and opening the space between the laminae of two juxtaposed vertebrae. By enlarging the intervertebral foramen, nerve root decompression is attained.

Lateral view
1. Nerve root
2. Spinous process
3. Intervertebral foramen
4. Facet joint
5. Transverse process
6. Spinal cord

• Microdiscectomy:
  • Laminotomy using a microscope, with a small incision and minor surgical manipulation.
• Laminectomy:
  • Removal of a lamina of a vertebra in order to decompress nerve roots. It is also performed in spinal stenosis to decompress the spinal cord.
• Arthrodesis:
  • The fusion of two vertebrae. It may be performed using metal plaques to accomplish fusion of both vertebral bodies or by inserting a bone graft between them. It is done in spondylolisthesis or scoliosis that require surgery. It is sometimes done after a laminectomy to add stability to the vertebra whose lamina has been removed.

• Chemonucleolysis:
  • The injection of a substance called "chymopapain"- inside the disc. This substance dissolves the nucleus pulposus. This diminishes disc pressure and compression on the nerve root. It also dissolves the substances contained within the nucleus pulposus that trigger neurogenic inflammation.
• Percutaneous discectomy:
  • The extraction of the nucleus pulposus from the intervertebral disc through a small skin incision.
  • Placement of a nucleus pulposus prosthesis by arthroscopy:
  • The extraction of the nucleus pulposus from the intervertebral disc through a small skin orifice and replacing it with a prosthesis.

Recommendations

The criteria for considering surgery for each type of structural anomaly are noted in the corresponding section. The recommendations for the surgical techniques described above are outlined below.

In instances of disc herniation requiring surgery, some of the existing evidence based recommendations advise:

Microdiscectomy, laminotomy or laminectomy. Laminotomy and microdiscectomy are of similar efficacy, although the latter is less aggressive and permits a faster recovery.

Chemonucleolysis is less efficient than microdiscectomy or laminotomy. Its complications, although rare, are serious. This surgical procedure should be considered only after previously ruling out allergies to chymopapain.

Percutaneous discectomy is the least efficient technique and should be avoided.

According to some of the existing evidence based recommendations, surgical treatment for spinal stenosis is laminectomy, eventually completed with arthrodesis.

Some of the existing evidence based recommendations advise arthrodesis in the spondylolisthesis cases considered for surgery.

In cases of scoliosis in which surgery is appropriate, the recommended surgical procedure is arthrodesis with instrumentation and bone graft.

The existing evidence based recommendations do not consider placement of nucleus pulposus protheses by arthroscopy, since this surgical technique had not been developed at the time of issuance of guidelines. Removal of the nucleus pulposus means also removal of the substances it contains, so although the fibrous ring may have fissures, its nerves are not stimulated and there is no pain. Posterior placement of the prosthesis allows the disc to maintain its cushioning function. It is recommended when disc fissure produces very frequent discomfort, which is intense and resistant to treatment.These are new techniques with very promising results when patients are properly selected. However, their long term effects are still unknown.