Lay Summary of Research
The lay summaries for thoracic outlet syndrome and piriformis syndrome that follow are intended to familiarize potential subjects with the advantages and disadvantages offered by the study protocols.
Naturally people will have questions that are not addressed by the summary; those interested in participating in the study will have ample opportunity to ask the questions that arise, and evaluate the answers given by the researchers and/or their own or other physicians and scientists.
Please address any questions and comments to loren@sciatica.org.
Download the Consent Form Here
LAY SUMMARY: MYOBLOC INJECTION FOR THORACIC OUTLET SYNDROME
The study in which you are being requested to participate is designed to test the effectiveness of Myobloc (Botulinum neurotoxin type B) in treating shoulder, arm and hand pain, tingling, weakness and numbness due to thoracic outlet syndrome. It has been determined that you have thoracic outlet syndrome, and that treatment of this type is more likely to be effective for you than conventional treatments of other causes of these problems.
Myobloc is a commercially available form of Botulinum type B toxin, produced in accordance with the regulations of the FDA. It has been used as an injection for some years in the treatment of spastic torticollis, another neck and shoulder problem. Botulinum toxin A has been used for many years for this purpose as well as ocular muscular defects in children. It has been demonstrated to be safe with no known serious side effects.
The proposed mechanism by which Myobloc reduces shoulder, arm and hand pain involves the effect of Botulinum toxin on muscles. Botulinum toxin inactivates the myoneural junction, the connection between nerves and the muscles they activate, in the local area of injection. Since your type of thoracic outlet syndrome appears to be due to the overtightening of the thoracic outlet muscles, this inactivation is likely to loosen the grip of the muscles, and relieve the pain that the spasm had caused.
Myobloc has been studied extensively in the laboratory and in use with people. Its effects last an average of three months. Preliminary studies in people with thoracic outlet syndrome have demonstrated that Myobloc can relieve this painful condition in people for whom other therapies, however intensively applied, were of no value.
In the proposed study your physician will study the conduction velocity of the upper extremity nerves when the thoracic outlet muscles tend to stretch them, to determine whether the nerves are actually affected by the tightness of these muscles. Excellent laboratory data for this determination has been obtained from more than 100 patients and many normals over the last seven years.
If you are diagnosed with thoracic outlet syndrome, then you will be given an injection of either 2,500 or 5,000 units of Myobloc. Neither you nor your doctor will know which medication you have received, though the assistant preparing the medication (according to a prearranged, random schedule) will make careful note of it.
You will be offered physical therapy, which has been found somewhat helpful to patients with thoracic outlet syndrome, and asked to return to our offices at two weeks, four weeks, eight weeks, and twelve weeks. At each visit you will receive a physical examination, electrophysiological assessment of the nerve we are studying, and you will be asked to update a short questionnaire.
The final visit at 12 weeks will assess the effects, if any, of the treatment. If there is evidence of response to either the injections or the physical therapy, you will be given an opportunity to continue treatment. If there is no response to either the physical therapy or the injections, then therapy will be discontinued.
This is the "adverse effects" profile for Myobloc, the medicine that will be used in this study. This table contains data from people whose neck muscles have been injected with doses of the medicine equal to, and two times as great as those that will be used in your case, (depending upon which randomized group you are in).
Different Studies
| Dry Mouth | 3(3%) | 1(3%) | 8(12%) | 36(34%) |
| Dysphagia | 3(3%) | 5(16%) | 7(10%) | 27(25%) |
| Cervical Dystonia | 17(16%) | 0(0%)b | 11(16%) | 18(17%) |
| Injection site pain | 9(9%) | 5(16%) | 8(12%) | 16(15%) |
| Infection | 16(15%) | 4(13%) | 13(19%) | 16(15%) |
| Pain | 10(10%) | 2(6%) | 4(6%) | 14(13%) |
| Headache | 8(8%) | 3(10%) | 11(16%) | 12(11%) |
| Dyspepsia | 5(5%) | 1(3%) | 0(0%) | 11(10%) |
| Nausea | 5(5%) | 3(10%) | 2(3%) | 9(8%) |
| Flu Syndrome | 4(4%) | 2(6%) | 6(9%) | 9(8%) |
| Torticollis | 7(7%) | 0(0%) | 3(4%) | 9(8%) |
| Torticollis Pain | 4(4%) | 3(10%) | 3(4%) | 7(7%) |
| Arthralgia | 5(5%) | 0(0%) | 1(1%) | 7(7%) |
| Back Pain | 3(3%) | 1(3%) | 3(4%) | 7(7%) |
| Cough increased | 3(3%) | 1(3%) | 4(6%) | 7(7%) |
| Myasthenia | 3(3%) | 1(3%) | 3(4%) | 6(6%) |
| Asthenia | 4(4%) | 1(3%) | 0(0%) | 6(6%) |
| Dizziness | 2(2%) | 1(3%) | 2(3%) | 6(6%) |
| Accidental Injury | 4(4%) | 0(0%) | 3(4%) | 5(5%) |
| Rhinitis | 6(6%) | 1(3%) | 1(1%) | 5(5%) |
None of the side effects observed so far have any serious consequences. For example, in all the testing done in various locations around the world, no one has ever gone to the hospital as a result of a Myobloc injection. In general, the benefits of Myobloc injection far outweigh the adverse effects.
If you have further questions, comments, or suggestions, please feel free to let me know.
Very truly yours,
Loren M. Fishman,M.D.
Principal Investigator
Lay Summary
BOTULINUM TOXIN INJECTION FOR PIRIFORMIS SYNDROME: NATURE AND PURPOSE OF THIS RESEARCH STUDY
The study in which you may participate is designed to test the effectiveness of Botulinum toxin in treating buttock pain and sciatica due to piriformis syndrome. If it is determined that you have piriformis syndrome, then treatment of this type may be more effective than conventional treatments used in other types of lower back and sciatic type pain.
DETAILS OF STUDY
Botulinum toxin is a commercially available form of medication, produced in accordance with the regulations of the FDA. It is already being used as an injection in the treatment of spastic torticollis (stiff neck) in dosages equivalent to those used in this study.
The proposed mechanism by which Botulinum toxin reduces buttock pain and sciatica involves its effect on muscles. Botulinum toxins inactivate the myoneural junction, the connection between nerves and muscles, in the local area of injection. Since piriformis syndrome is due to the powerful tightening of the piriformis muscle, this inactivation is likely to loosen the grip of the muscle sufficiently to relieve the pain that the muscle tightness had caused.
Botulinum toxin has been studied extensively in the laboratory and in use with people. Its effects last an average of 3-5 months. Preliminary studies in people with piriformis syndrome have demonstrated that Botulinum toxin can relieve this painful condition in people for whom other therapies, however intensively applied, were of no value.
In the proposed study your physician will study the conduction velocity of the sciatic nerve when the piriformis muscle has been stretched across it, to determine whether the nerve is actually affected by pressure from this muscle. Excellent laboratory data for this determination has been obtained from more than 1000 patients and 88 normals over the last ten years.
If you are diagnosed with piriformis syndrome, qualify and wish to participate in this study, you will be given an injection of Botulinum toxin. You will be given physical therapy twice weekly which has been found quite helpful to most patients with piriformis syndrome, and asked to return to our offices at two weeks, four weeks, eight weeks, and twelve weeks. At each visit you will receive a physical examination and you will be asked to update a short questionnaire.
A final visit at 12 weeks will assess the effects, if any, of the treatment. Whether there is evidence of response to either the injections or the physical therapy, or not, you will be given an opportunity to continue treatment at a dosage to be determined by the study doctor. At the end of the twelfth week following the final injection, however, your participation in the study will have ended.
You may experience the following side-effects if exposed to Botulinum toxin treatment for piriformis syndrome:
• Dry Mouth
• Stiff Neck
• Pain from the injection
These appear to be the most common side-effects. No patient in our experience has been seriously ill or hospitalized from an adverse effect of Botulinum toxin injection. These and all other adverse effects that we have encountered thus far are transient, though occasionally they may last for weeks. One case related to dry mouth lasted two months.
Loren M. Fishman, M.D., Principal InvestigatorStudy Personnel