3rd TNA CONFERENCE REPORT

Pittsburgh, USA - OCTOBER 25th to 29th 2000

for the UK TN Association

 

 

THE IMPORTANCE OF A DIAGNOSIS

 

Face pain disorders are difficult to diagnose because the head is the centre of many "wires". The origin of  pain in the face can be vascular, neurogenous, musculoskeletal, systemic or psychogenic, and it is common that all those factors mingle. The consultant has to work with the patient as a team to find out the origin of pain. The acurate description of the pain is essential, as well as tests to confirm the diagnosis.

Consultants should use a questionnaire (like the McGill pain questionnaire) to assess the pain. Dr Joanna Zak found that Typical TN patients are using words like sharp, shooting, unbearable when they fill it in. The word "nagging" exclude typical TN. It is best to ask the patient to complete the questionnaire each time they come for a consultation. It enables the consultant to assess the effectiveness of the treatment, and understand the evolution of the pain. A "pain diary" is also a very valuable source of information for both the patient and the doctor.

The consultant has to assess the psychology and behaviour of the patient, the effect of the pain on his quality of life. If you attend a pain clinic, don't be upset if they ask you to see a psychologist: they are only trying to help finding the cause of your pain.

As a patient, if you feel that your consultant does not listen to you, go away!

 

Typical TN must correspond to the following characteristics:

- Sharp, shooting attacks that come and go

- The pain is restricted to one (or two and rarely three) branches of the trigeminal nerve.

- The pain is limited to one side of the face (95% of the time)

- There are trigger zones

- The pain runs into cycles.

 

 

MEDICAL THERAPY

 

Anticonvulsant

They are still the best treatments for TN:

- Carbamazepine (Tegretol). 75% of typical TN patients respond to this treatment. In fact, a positive response to Tegretol is often a clue to confirm the diagnosis.

- Oxcarbamazepine (Trileptal), a new form of carbamazepine.

- Dilantin (Phenytoin), less effective, but often good in conjunction with Tegretol.

- Lioresal (Baclofen) usually recommended for patients with MS.

- Lamictal (Lamotrigine), for patient who cannot tolerate carbamazepine or oxcarbamazepine.

- Valporate, for patient who cannot tolerate carbamazepine or oxcarbamazepine.

- Gabapentin (Neurontin) little side effects but less effective.

 

Opioids

Neuropathic pain does not respond as well as other sort of pain to opioids. Although there is no scientific study on the effect of opioids on TN or Face Pain disorders, some opioids have been use with effectiveness: Clonadine, Lidocaine, Morphine (at twice the expected dosage), and Tramadol.

Opioids are sometimes used as "nerve blocks" to allow the consultant to reach a diagnosis and then prescribe a more appropriate medical therapy, or to stop a very severe pain temporarily. They can also be used  as a diagnostic tool because some chronic pain respond to certain opioids and some others don't.

Tolerance and side effects are two important factors in the management of opioid treatments. The patient becomes physically independent, which is different to addiction, a chronic brain disease.

 

 

DENTAL ASPECT OF FACIAL PAIN

 

Efforts need to be done to take care of "pain" patients, those who have been misdiagnosed or treated ineffectively. If not aware of TN, a dentist tends to confuse the site of the pain (in the teeth) with the source of the pain (trigeminal nerve). He will then end up doing root canals inappropriately. 3% of patients having a root canal extraction end up with neuropathic pain.

Efforts are continuously done to educate dental students nowadays. For older dentists, their education lies on numerous publications, but nobody can force them to read... So if you are about to have a root canal extraction, make sure your dentist has taken some X-rays and is sure that the cause of your pain is dental.

 

When you have TN, you NEED TO go to the dentist regularly. You are often not brushing your teeth well, you also eat on one side only, and having a dental problem on top of your TN can only make it worse. A very good local anesthesia is needed. Anesthesia is like a nerve block, and you should not feel pain during dental work.

 

 

WHEN TO REFFER FOR SURGERY ?

 

There is definitely a tendency to consider surgery before having exhausted all medical therapies. TN pain gets worse overtime, whatever we do; surgery can provide longer pain free periods and a better quality of life. But as mentioned earlier, the patient and the consultant must be sure they have reached the correct diagnosis in order to prevent people to have unnecessary surgery.

 

When is the right time?

- When the correct diagnosis is made and verified.

- Do not wait until all medicines on the market have been tried.

- When medical therapy no longer works: when the pain is not controlled, or/and when the side effects are too strong, or/and when a good quality of life is no longer possible.

- When you have confidence in your neurosurgeon

- When a MRI shows evidence of compression (for an MVD)

- As there are risks associated with all surgeries, if the medical therapy is effective and there is no sides effects, there is no need to have surgery.

 

Is age a good criteria?

Neurosurgeons prefer to talk about life expectancy and fitness of the patient:

- If the life expectancy of the patient is lower than 10 years, a destructive procedure is better.

- If the life expectancy is between 10 and 20 years, a destructive procedure can be done because even if it fails, the patient usually responds better to medical therapy. If the patient is fitted, he can have an MVD.

- If the life expectancy is greater than 20 years, MVD is the procedure of choice.

 

In 1989, Dr Zak started a study on 15 Typical TN patients who rejected surgery and had treatment with oxcarbamazepine. They all had a recurrence of pain after 20 months. Recently, she managed to contact them again: They ALL had surgery and they ALL said that they should have been sent to surgery earlier.

Referring a patient to surgery is teamwork between the patient and the consultant. Faith and correlation with the physician is an important factor for surgery. Psychological factor is to be taken into account as well.

 

SELECTING AN OPERATION

 

There are two types of operation:

1/  Destructive procedures:

Radiofrequency Rhizotomy, Balloon compression, Glycerol injection, Gamma Knife. Those procedures are damaging the trigeminal nerve one way or another. When the nerve is damaged, it is very likely that the pain will be replaced by numbness in the face. When the numbness wears of, it is very likely that the pain will come back.

2/  Invasive procedure:

MVD or Microvascular Decompression. The nerve is not damaged, so the risk of numbness is minimal and only occurs if the nerve is touched during surgery.

 

The criteria you should look at:

- Do you have the correct diagnosis? Some destructive procedures may worsen neuropathic pain.

- Are you prepared to have numbness in your face?

- Are you prepared to take some risks?

- Is your neurosurgeon experienced in ALL procedures or only one?

- Do you feel he is giving you good information on ALL procedures?

- Are you actively participating in the choice or are you in too much pain to make a rational decision?

 

Some facts:

- Patients with Typical TN do respond better to surgery.

- Surgery usually woks well for the "sharp shooting" factor, but may not help for the "dull, aching, constant" factor.

- Patients with typical TN will do better with an MVD.

- If a patient is young, some neurosurgeons are reluctant to do a destructive procedure, unless the patient does not want to take the risks associated with the MVD.

 

IT IS NOT WRONG TO BE AN EDUCATED PATIENT,

IT IS NOT WRONG TO ASK QUESTIONS AND EXPECT STRAIGHT ANSWERS.

 

 

RESULTS AND COMPLICATIONS OF OPERATIONS

 

The major complications after surgeries are numbness and recurrence. Mr John Alksne, Neurosurgeon, says that his treatments of choice are MVD and Gamma knife. He thinks that recurrence occurs too soon with Glycerol, and that Radiofrequency and balloon compression often give too much numbness.

 

Here is his study among 702 patients.

Excellent results : pain free, no medication

Good results: pain free, occasional medical treatment with no side effects.

Fail: Still requiring medical treatment with side effects, still in pain.

 

 

Excellent

Good

Fail

 

MVD: 406

91%

6%

2%

short term

 

66%

15%

19%

long term

Radio Frequ: 20.

87%

6%

7%

short term

 

71%

10%

19%

long term

Glycerol : 276

83%

9%

8%

short term

 

52%

12%

36%

long term

 

MVD: 5 deaths, 3 of them due to cerebral haemorrhage. 1 temporary facial weakness, 2 mild earring loss, 7 complete earring loss, double vision trouble got all solved between 3 to 6 months.

Radiofrequency and Glycerol: the cases of dysesthesia (bothering numbness) are more frequent with Radiofrequency than Glycerol injection.

 

Professor Brisman presented his study on Gamma Knife: He treated 332 patients in three and a half years.

Pain relief between 0 to 120 days: 91%

After 1 year: 82 to 86% patients are pain free, most of them had Typical TN.

The complications included mild bothersome numbness of the face in 5%, moderately bothersome numbness in 4%. No death, no anesthesia dolorosa, no chewing problem, no eye problem, no stroke. Pr Brisman is definitely a big defender of Gamma Knife. He thinks it is safe, and if pain reoccurs, then another gamma knife procedure is possible.

 

Mr Richard Zimmerman, MD

He concentrated on MVD because it is the most scary and tried to tell us how we could avoid major complications:

- If your neurosurgeon does not answer your questions, do not trust him!

- Have a MRI, and have it read properly

- Understand what is going to happen during the MVD

 

 

DEMONSTRATION OF SURGICAL TECHNIQUES

 

Balloon Compression

The objective of this operation is to damage the myelin by compressing it with a tiny balloon. This will result in "switching off" the pain. This technique has been used since the 1950's.

The operation is done under general anesthesia. The surgeon inserts a needle and guides it up to the ganglion with the help of a fluoroscope. When the needle is in place, the surgeon inflates the balloon for approximately one minute. Doing it longer will induce great numbness, which can lead to other complications. The pressure of the balloon is constantly measured; the more the pressure, the greater the numbness.

2/3 of the patients will wake up with mild numbness. This technique is better when the forehead/eye branch of the Trigeminal nerve is affected, because it can avoid corneal numbness.

Although this technique is fairly simple, it is important to check that your neurosurgeon monitors the pressure and will take x-rays to verify where the balloon has been inflated.

 

Radiofrequency Rhizotomy or Thermocoagulation Stereotaxic Rhizotomy

The objective of this procedure is to damage the nerve by heating it, using light radiowaves provided by a radiofrequency unit. Electric current has been used to treat TN as early as 1930's. Dr William H.Sweet has refined the technique in 1965.

The patient is put asleep with a short-lasting general anesthetic to allow the surgeon to place the curved needle in the cheek and guide it to the ganglion with the aid of a fluoroscope. When the needle is in place, the electrode is inserted into it. The patient is then awaken, and the surgeon triggers light radiowaves so the patient can tell which area of the face is stimulated. This feels like a tingling sensation. When the surgeon has located the precise painful area, the patient is put back to sleep, and the nerve can be heated to the point where a lesion (damage) is created. This can be repeated several times during the operation.

The key to the success of this procedure is to produce enough numbness to relieve the pain, but not too much to induce dysesthesia (severe painful numbness).

It is tolerated by almost anyone, and it can be repeated. It is the technique of choice for patients with MS and TN, but this operation often aggravates Atypical Facial Pain. When the numbness wears off, it is likely that the pain will come back, but the operation can be repeated.

If the patient is worried about the sensation of numbness, the surgeon can inject some Novocain (a local anesthetic) in the nerve for a moment: this will give an indication to the patient of how it feels to be numb in a precise area of the face.

 

Glycerol Injection

The objective of this technique is to damage the nerve with glycerol, an oily alcohol. Alcohol has been used since 1909, and it has been replaced by glycerol in the early 1980's.

The patient is put under sedatives during the whole procedure. After a local anesthetic, The needle is guided with fluoroscope into the sac (or Meckel's cave). Meckel's cave is where the ganglion is, and the ganglion is the "relay station" where the Trigeminal nerve separates into 3 branches before going into the face. The patient is asked to sit, and the surgeon injects a liquid dye solution to confirm that the needle is at the right place. This also allows him to see the amount of glycerol needed and the exact size of the sac. The major risk is an infection (rare). The patient gets mild sensory loss, the pain recurrence rate is 51%. This is high, but the procedure is repeatable.

 

All those percutaneous procedures do not treat the cause of the problem, but only the Microvascular decompression does. They slightly damage the nerve with compression, heat, or a chemical solution in order to stop the message of pain. They all replace the pain by partial numbness, which is often considered as a fair trade by the patient. They all work better with typical TN patients, and their effect is limited in time.

 

Microvascular Decompression

This is the procedure of choice when a MRI scan shows an actual vascular compression. It is therefore very important to have a good MRI scan, and to have it interpreted by an expert. Imaging is making progress in terms of quality, but some neurosurgeons are still reporting compression by small blood vessels that couldn't be spotted on the MRI.

The patient is under general anesthesia. An opening is made right behind the ear, to allow the surgeon to see the base of the trigeminal nerve. A microscope is brought in, and the surgeon lifts up all arteries and blood vessels compressing the nerve. Small vessels can be destroyed without causing problem. When all compressing blood vessels are taken away from the trigeminal nerve, the surgeon introduces small pieces of Teflon to prevent the blood vessels going back on the nerve again. The opening is then closed with stitches or staples, and the patient usually spends a few hours in the intensive care unit.

As the trigeminal nerve is very close to the "earring" nerve, you need to have this nerve monitored during the procedure (make sure your neurosurgeon does that!).

If the operation is successful, the pain is relieved without numbness. Numbness occurs when the Trigeminal nerve has been damaged during the surgery, and this occurs in 3 to 5% of the cases.

When you are considering having an MVD, bring the issue of headache, Spinal Fluid leaks, hemorrhage: if you feel that your neurosurgeon does not have straight answers to those questions, consider seeing someone else.

 

Gamma Knife

This is the newest procedure in the treatment of TN. It aims at mildly injuring the nerve with a small amount of radiation beams (201 beams, targeted with high precision).

The surgeon (or nurse) apply an anesthetic cream on the scalp or administrate a local anesthetic with a seringe in order to fix a frame around the head. Measures are taken, and the imaging is brought back to the computer and carefully examined by the surgeon. Once the target is located, the patient goes in the Gamma Knife machine, the frame is fixed to the gamma knife, and the procedure starts. The patient feels nothing, some often go to sleep at that point.

Pain relief is not often immediate. It takes an average of  one to three months to get relief. Another MRI scan is done six months after the procedure, so the surgeon can see the difference.

There is practically no side effects or major complications after a gamma knife treatment, and the procedure can be repeated.

One person in the audience brought up the fact that radiation can cause cancer. The surgeon said that it was in fact a theoretical risk, but radiations used for the treatment of  TN are so small that this can not happen. He added that gamma knife has been safely used for 10 years.

 

 

ATYPICAL TN AND ATYPICAL FACIAL PAIN

 

This session has been quite remarkable: we had 4 different speakers, all experts in facial pain, all giving a different definition of "Atypical" pain... At the end of the session, all medical experts agreed to meet in the future and try to work out a precise definition of "Atypical". I hope they will do it!

 

Mr Kim J. Burchiel, MD

1/ Typical TN

A good response to carbamazepine, all classic symptoms, no sensory loss, pain free intervals.

2/ Atypical TN

Unilateral episodic pain superimposed on some degree of lingering background pain. A detectable sensory loss is more common, the response to carbamazepine is limited.

3/ Neuropathic pain

There is a history of trauma to the nerve (facial trauma, difficult dental extraction, sinus surgery, ...). The pain is in a branch. The pain can be episodic or constant, but the constant factor is predominant. This pain does not respond to medication well, but do respond to nerve blocks.

4/ Atypical Face Pain:

Almost no common feature with TN. The pain can be bilateral. It is not responding to medications, and depression is a factor.

BUT, those 4 classifications are often not separated. They are often linked to one another, and it is important for the consultant to know how the pain started: It gives him a clue on how to treat it best.

 

Mr Steven B. Graff-Radford, DDS

Atypical is : A wastebasket disorder, a disorder where surgery failed to relieve the pain, a psychological disorder. The first definition of Atypical TN was found in 1927: " any pain which do not meet the criteria for TN". Since then, Atypical TN includes many different symptoms, the most common being a dull, aching, constant pain in the face.

The origin of the pain can be psychogenic, but 40% of "atypical" patients are not depressed. It can also be neuropathic, when the pain occurs following a trauma. Or it can be vascular (an inflammation of the nerve) like in cluster headache or facial migraine.

 

Mr David a.Wright, MD (neurologist)

For the physician, Atypical often means " I have never seen this before". Because there is no typical recognition, it is easy to fall in the psychological path. A good assessment of the patient is needed to see if the origin of pain is psychological.

Some conditions are very similar to TN and often called atypical. This include temporal arthritis, cluster headaches, Herpes Zoster or shingles, glossopharyngeal neuralgia.

Diagnosis is no w better with the help of CT Scan and MRI. Every patient with a face pain condition should have an imaging of the head.

 

Dr Kenneth Casey, MD (neurosurgeon)

Dr Casey concentrated on people diagnosed with Typical TN who developed a form of Atypical pain in time.

TN patients do not use their face muscle properly: they often eat on one side, avoid moving their mouth when talking, etc. This can lead to muscle pain, and this can be treated successfully by simple muscle exercises.

When the pain is initiated by an injury, the technique aimed at stimulating the nerve (with electrodes) can work. But this technique is still experimental, and it is too soon to draw conclusion on its efficacy.

A neurectomy (cutting the nerve) is not a good solution because it leads to other complications like anesthesia dolorosa.

Neuropathic pain should be treated with tricyclic antidepressants.

Most importantly, the patient has to be taught how to manage his pain, and attending a pain clinic for "atypical" face pain patients is only beneficial.

 

 

TAking the Natural Path to a drug-free pain-free Life

 

This has been a very interesting session presented by Gwen Asplundh, a TN patient who found success in treating her pain with a special diet. Her nutritionist (and sister in law) Emily Jane Lemole, did many research before finding the right treatment for her patient.

Gwen started to treat her pain with a glass of whisky before eating. She soon found out that it wasn't helpful and quite a bad habit! She then tried to get as drowsy as possible with painkillers, with no better effect. She is allergic to carbamazepine (tegretol) Neurontin as been ineffective, and baclofen has had terrible side effects. She had a Gamma knife surgery in 1996, but pain returned after 5 months. She also tried acupuncture, aromatherapy, anything that could help her to avoid taking medications.

She started her new diet in May 1997. She has been free of pain since then, except on 2 occasions, when the pain as been controlled by vitamin B12 injections. Vitamin B12 (or cobalamin) is essential is the production of myelin, the protective coating around nerves.

She follows a Pritikin diet : sugar, salt, alcohol free, no caffeine, vegetarian except for fish. Dairy free.

She takes vitamins and supplements daily, cod liver oil caps, folic acid caps etc (I have her own diet at home if you are interested!)

She started her treatment with vitamin B12 injections 3 times a day, and she still uses B12 injections with local applications of Capsaicin Cream when pain returns.

Mrs Lemole said that she treated 4 patients with TN so far, all with success, and all with a different diet according to their general condition. This number is too small to draw conclusions, but this is a risk free way of dealing with the pain. If no result is achieved within 3 to 4 weeks, then you can consider that this path is the wrong one for you. You can always follow the diet while taking medications.

 

A good book to read on the subject:

" The New Orthomolecular Nutrition" by Abraham Hoffer.

 

 

Alternative treatment method: Upper Cervical Chiropractic

 

An upper cervical chiropractor is a doctor in the field of chiropractic with training in the structure, function and bio-mechanics of the upper cervical spine.

The theory behind the practice

Many nerves pass through the spinal cord. If a patient presents a misalignment, it is very likely that any movement of the head will hyper-activate the nerve and cause pain. This is often the case with back pain and headaches, and some patients with TN are reporting good results with this upper cervical technique. In short, the upper cervical chiropractor believes that TN pain can be caused by a trauma in the neck or head, or simply by an inadequate posture.

How does the treatment take place?

The upper cervical chiropractor will first start by taking x-rays of the head: profile, head down, back. He will then examine the patient from head to toes, take some measurements, make temperature differential comparisons to help determine the degree of nerve involvement in the pain, and ask him about his medical history and symptoms. The patient has to fill in a pain questionnaire on every consultation, in order to be able to monitor the results of the treatment.

The treatment takes place in 2 phases:

First, the patient comes three times a week during the first two weeks, and then twice a weeks for the next two weeks. After this four weeks period, the progress is carefully assessed and the patient only comes back if the pain returns.

The treatment consists in several gentle manipulations, with hands and fingers, sometimes with some mechanical instruments. This does not hurt.

Who is a candidate for this treatment?

Any TN patient between 18 to 80 years old! An MRI must be done prior to the upper cervical treatment to rule out a tumor or Multiple Sclerosis. The patient can continue to take his medications during the treatment, and slowly decrease the dosage if his condition improves.

The risk of this treatment is minimal, there are no randomise control trials to prove that it is effective, but this is worth trying!

 

What do we do if the pain comes back?

 

If pain comes back after a period of remission

You have to go back on medications. Make sure that you are taking the medications properly: slowly increasing the dosage, intakes at regular intervals during the day, slowly decreasing it when advised by your consultant. It can take several weeks before anticonvulsant like Tegretol start to be effective, so be patient. It is sometimes better to have a combination of two drugs instead of a massive dosage of one. If the problem persists, you should discuss surgical procedures with a neurosurgeon who is able to offer you advice on ALL possibilities.

 

If pain comes back after surgery

You need to go over a full investigation with your neurologist or neurosurgeon to compare this "new" pain with the original symptoms. Is it exactly the same? All three neurosurgeons participating in the discussion have emphasised the importance of  reassessing the situation. This is particularly true when you are significantly numb after a percutaneous procedure. You cannot have TN and numbness at the same time, but you can have a pain that mimics TN. In that case, all procedures for TN will make the pain worse, so you must be careful and seek an expert advise.

Recurrence of pain can occur with all procedures.

- If you had an MVD, once you are sure that the pain is still TN, you can go back to medications or try one of the peripheral procedure. You can also have another MVD, but this is rarely indicated. A repeated MVD long after the first one is difficult to perform because the Teflon adheres to the trigeminal nerve and access/examination is not easy for the neurosurgeon. A second MVD is recommended only if an MRI shows evidence of compression again. The risk of sensory loss is higher with the second MVD, and the success rate is lower.

- If you had one of the percutaneous procedure, you can go back to medications or you can have it again. As a repeated percutaneous procedure will damage the nerve once again, the risk of bothering numbness is greater, but the success rate is about the same. There is no limit to the number of percutaneous procedures you can have; this is a personal assessment.

If you had sharp shooting pain before the procedure and the recurrent pain is now burning and aching, a repeated procedure is not recommended. It is also possible that the pain has moved to another branch of the trigeminal nerve.

 

 

A look at the future

 

1 - Fields needing improvement

 

- We need to understand the mechanism of TN pain. For now, we know that TN has something to do with the myelin sheat (protective coating of the nerve), we know that the cause of TN is often a vascular compression. But there is no prospective natural history of TN, and therefore no cure.

 

- We need to encourage randomised control trials for the medical and surgical treatment of TN. Randomised control trials are studies involving patients and professionals in order to scientifically prove the efficacy of a treatment. Such studies have been made on Tegretol, Pimozide, Lamotrigine and Baclofen.

There has not been any randomised control trials on surgeries. The only data we have are personal compilations from neurosurgeons. There is a real need to pursue those issues as they are the only scientifically based studies on which patients can rely on.

 

1- Fields of improvement

 

- The quality of MRIs is getting better. It is more accurate when contrast is used. This is a substance that you inject in the patient's blood stream to enhance the picture. But MRI is not showing compression form small blood vessels. A neurosurgeon presented a study on 25 patients who had an MRI before an MVD: the compression has been visible on the MRI for 13 patients. The other patients had venous compression not appearing on the MRI.

- MRA (Magnetic Resonance Angiography) technique has improved as well. It is now possible to have "thin-slice" or "thin-cut" MRAs with high resolution. MRIs and MRAs have to be read by experienced specialists; it is not that easy to see a compression.

 

- A few surgeons are beginning to use an endoscope to do MVDs. The endoscope is a small camera that supposedly allows smaller openings in the head and a better 3D view around the nerve. A study was presented showing that the endoscope picked up compressing blood vessels that were missed by a standard microscope. There is a hope that the use of endoscope will make the MVD safer and more accurate.

 

- Research is making giant steps nowadays on the mechanism of pain. Once the biochemical reason of pain is fully understood, than we will be able to produce new drugs to block the pain in a more targeted, effective way.

The National Institute of Neurological Disorders and Strokes (NINDS) is interested in TN research. They are committed to pain research, making this possible through workshops and symposiums. They have recently published a paper "TN: opportunities for research and treatments". They do have some credit to pursue the research on Epidemiology of TN, etiology and pain mechanism. They are also very aware that there is a real need to assess the pain. The research on TN will also benefit all Facial Pain disorders.

 

- The American TNAssociation initiated a worldwide survey for TN patients two years ago. Polly Potter is starting to draw conclusions from the survey. Today, already has 5285 answers. Among them, 3736 were diagnosed with TN. 100 have TN associated with MS. 2042 did have dental treatment before the TN started.

Polly will publish the results of the survey in the next TN Newsletter, but she gave us some interesting figures:

A total of 386 people had surgery. 242 are pain free (62%), 76 have partial relief (20%0, 26 reported no change (7%), 12 said the pain was worse after the surgery (3%), and there is a lack of data on 30 (8%).

Polly and the TNAssociation do encourage people to fill in the questionnaire: it will be an incredible data ready to be analised by professionals.

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