Treatment of Thoracic Outlet Syndrome (TOS) With Botox

University of British Columbia

Status and phase: Completed; Phase 2

Conditions: Thoracic Outlet Syndrome

Treatments: Drug: Botulinum Toxin Type A injection (BOTOX)

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT00444886

Data not known

H06-03355

Details and patient eligibility

About

The purpose of this study is:

1. To assess the effect of BOTOX injection to the scalene muscles on the severity of pain from TOS.
2. To assess the effect of BOTOX injection on numbness and tingling and quality of life.

Full description

Background:

Thoracic Outlet Syndrome (TOS) is a symptom complex consisting of pain, paresthesias and often functional impairment caused by compression of the neurovascular supply to the upper limb. Impingement may occur at the interscalene triangle, and both anesthetic blockade and chemodenervation of the scalene muscles have been shown to temporarily improve symptoms of TOS in non-randomized controlled trials.

Objective:

To assess the effect of Botulinum Toxin Type A (BTX-A) injections into the scalene muscles on pain, paresthesias and function in subjects with TOS.

Hypothesis:

BTX-A injected into the anterior and middle scalene muscles will reduce the irritation on the neurovascular structures at the interscalene triangle in subjects with TOS. This will lead to reductions in pain and paresthesias, and improvements in function when compared with injection of placebo.

Intervention:

Each subject will receive an injection under EMG guidance into the anterior and middle scalene muscles of either 75 units of BTX-A (experimental group), or normal saline (control group). Both groups will be provided with a stretching and strengthening exercise program.

Enrollment: 40 estimated patients

Sex: All

Ages: 19+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age at least 19 years
• Medically stable
• Able to give informed consent
• Meets criteria for clinical diagnosis of TOS
• Symptoms of TOS present for at least six months
• Have had EMG studies and a CT or MRI scan of the cervical spine

Exclusion criteria

• Prior treatment with BTX-A
• Allergy to BTX-A
• History of botulinum toxicity
• Prior scalenectomy
• Surgery for TOS planned within six months
• Use of blood thinners, i.e., warfarin; unfractionated or low molecular weight heparin
• History of Myasthenia Gravis, Eaton-Lambert Syndrome or Shy-Drager Syndrome
• Unable to complete follow-up assessments at 6 weeks, 3 months and 6 months
• Any abnormalities on EMG, CT or MRI studies suggesting an alternate diagnosis
• Pregnancy or planned pregnancy within six months

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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40 participants in 2 patient groups

1

Active Comparator group

Description:

To assess the effect of BOTOX injection to the scalene muscles on the severity of pain from TOS.

Treatment:

Drug: Botulinum Toxin Type A injection (BOTOX)

Drug: Botulinum Toxin Type A injection (BOTOX)

2

Active Comparator group

Description:

To assess the effect of BOTOX injection on numbness and tingling and quality of life.

Treatment:

Drug: Botulinum Toxin Type A injection (BOTOX)

Drug: Botulinum Toxin Type A injection (BOTOX)