These are the most common queries regarding disc degeneration, disc prosthesis and ADR surgery.
f you cannot find what you wish to know, do not hesitate to contact us by email at or through nuestro formulario.

Disc Degeneration

1. What are the causes of disc degeneration?
Degeneration is a natural process directly related to aging. We all age and as we age all our joints undergo degeneration; to a greater or lesser extent; in some cases becoming painful and in others not.
Aging is therefore the most common and major cause of degeneration. The differences between individuals are mainly due to genetic makeup. Other causes are traumatic, metabolic, etc.

2. What is a herniated disc?
It is a herniation of the nucleus pulposus of the disc which is the hydrated center of the disc. It is caused by weakness and rupture of the ring that contains the nucleus. The ring usually breaks due to degeneration although in some cases this can be favored by trauma or overexertion.

3. What are the symptoms of a spinal disc problem?
Degeneration causes lumbar or cervical pain and in cases of nucleus pulposus herniation there is sciatica.

4. What tests are carried out on patients to decide if surgery is necessary?
An X-ray of the spine in movement in order to observe the mechanics of the spine and of the segment to operate, as well as a lumbar MRI.

5. When should a patient undergo surgery?
When back or neck pain has become chronic and is not improved by non-invasive treatment.
Also when a patient’s quality of life of is limited by pain.


1. What are the current surgical solutions to solve a problem of a lumbar or cervical disc degeneration and the pain it causes?
The most common surgery performed is arthrodesis or traditional lumbar or cervical fusion.
In this surgery, as the name suggests, vertebrae are fused or fixated so as to remove the degenerated disc and thus the pain it causes.
A new alternative is artificial disc replacement (ADR) with a prosthesis.

2. What is ADR surgery?
It is the replacement of a painful degenerated disc by an artificial disc.

3. What are the main advantages of ADR surgery with regards to fusion?
They are many and varied. It’s all explained in the section What is ADR?.

4. Is ADR a very expensive operation?
It is much cheaper than the alternative. Prostheses are cheaper than the implants used for fusion.
As recovery is much faster, this also reduces labor and social costs.

5. If it is such an advantageous technique, why it is not more commonly used?
Because of the complexity of the anterior approach.
This complexity is overcome with training and experience.

6. During the operation is the anterior longitudinal ligament sectioned?
Yes, both in cervical and lumbar spine operations.
We do not believe that re-suturing the ligament re-establishes its anatomy or functionality.

7. Is ADR surgery, that is to say disc replacement by an artificial implant, recommended in all cases of spinal disc degeneration?
No. We do not implant artificial discs in the following cases:
Spondylolisthesis with or without spondylosis, previous spine surgeries that have involved the posterior articular facets in more than 50%, severe atrophy of the multifidus back muscle, high pelvic incidence or acutely inclined superior sacral surface, previous anterior abdominal surgery, especially if this involved the retroperitoneal space and finally, bone weakness, osteopenia and osteoporosis.
Patients with a history of allergy to metals must undergo an allergy test to metals, including aluminum.

8. Do we use an anti-fibrotic barrier in lower back surgery?
No. We do not consider it has any advantages and believe that any foreign material introduced into the retroperitoneal space could contribute to fibrosis and increase the chances of infection.

9. When is a bone densitometry test requested?
In the case of women over 30 and men over 40 it is necessary to perform a bone densitometry test preoperatively.

10. Do we use bone wax?
Yes, we do in the case of cervical spine surgeries. We use a small amount of bone wax at the rear edge of the upper and lower endplates.
We have not seen any cases of infection in cervical spine surgeries in which we have used bone wax and we believe that its use can prevent heterotopic ossification.

11. Potentially, any patient can opt for ADR?
No. There are many anatomical and psychological reasons that can cause this type of surgery to be contraindicated in some cases. A long history of pain or drug consumption or several previous surgeries can be excluding factors that make this type of surgery inadvisable.

Postoperative issues

1. Is there a lot of pain during the postoperative period?
No. Patients can stand the next day and are discharged two or three days after surgery.

2. Are there any risks or complications?
Yes, as with any surgery. Risks in this type of operation are mainly approach-related; as an anterior approach is used it is necessary to mobilize the abdominal vessels, which means that they can be accidentally lacerated.
This is a very rare complication and is controlled and resolved during the operation itself.
The new generations of discs (better designs and materials) no longer give rise to the complications originally associated with artificial discs themselves.

3. Can you say that the patient leads a normal life after surgery? Including former physical activities?
Yes. The aim of the operation is to restore patients’ quality of life and ability to carry out physical activities that they possessed before the onset of pain.

4. What is the recovery time for patients who undergo this new surgical technique?
Two or three days of hospitalization and two to six weeks to return to work, depending on whether the operation was performed on the lumbar or cervical spine.

5. Can the hernia recur?
No. When a disc prosthesis is put in place, hernias do not recur.

6. Do you recommend patients take nonsteroidal antiinflammatory drugs (NSAIDs) after surgery?
Yes. We recommend our patients take NSAIDs for at least three weeks after surgery. It is known that these drugs inhibit bone growth and thus reduce the likelihood of occurrence of heterotopic ossification.

7. What type of physiotherapy protocol is followed after surgery?
We provide a comprehensive rehabilitation treatment for our patients during their stay in Barcelona. Our specialized physiotherapists work with patients from the day after the operation, twice a day, during the time they are hospitalized. We also provide a rehabilitation protocol to be followed during their hotel stay. Laia, our back rehabilitation specialist, works in a personalized way with patients while they are in Barcelona and until the day they leave the city. When patients return home, Dr. Pablo Clavel is responsible for patients’ follow-up and each patient receives recommendations and specific instructions to enable them to continue their rehabilitation at home.


1. Is the implanted prosthesis designed to replicate the function of a natural disc?
Yes. Most prostheses are designed to fully replicate the functions of a healthy natural disc. We choose the disc with the design that makes it closest to a natural disc.

2. If it is the most similar to a natural disc, why is it not used by all surgeons?
Most of the surgeons do not use any of the models that currently exist due to the technical complexity of the surgical approach.

3. Are prostheses custom-made?
There are different sizes and it is necessary to use the correct size for each patient.

4. Are there different types of prostheses? What are the differences between these?
Differences consist in the materials used, the mechanical designs and the manner in which they are anchored to the bone of the vertebrae.
For example, there are manufacturers that use metal, others use polyethylene in combination with metals such as titanium or cobalt-chrome. Finally there are more sophisticated designs combining metal with shock absorbing polyurethane (a polymer that mimics the natural nucleus).
Mechanically prostheses are usually of the ball and socket or inverted kneecap type.

5. In which patients are these prostheses indicated?
Patients with low back pain or chronic neck pain due to a degenerated disc (worn).

6. What artificial disc designs do you use?
Mainly M6C and M6L for both cervical and lumbar spine surgeries.
We have occasionally used Activ-L Aesculap, especially at the level of L5-S1. It is indicated if the surface of the L5 is concave. The convexity of the upper platform of Activ-L fits perfectly into the pronounced concavity of the anatomy of some patients.