Botulinum Toxin Injections for Thoracic Outlet Syndrome

Phase 1

• Conditions: Thoracic Outlet Syndrome
• Interventions: Other: Normal Saline injection; Drug: Botulinum Toxin Type A

• Registration Number: NCT01405482
• Lead Sponsor: University of British Columbia

Brief Summary

Botulinum toxin type 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.

Detailed Description

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.

Study design:

Double-blind, randomized, placebo-controlled parallel groups effectiveness trial evaluating changes in pain, paresthesias and function before, at six weeks and four months following injection.

Study population:

Sixty subjects at least eighteen years of age with a clinical diagnosis of TOS of at least three months duration but less than one year, referred to our practice for management of TOS.

Intervention:

Each subject will receive an injection under EMG guidance into the anterior and middle scalene muscles of either 100 units of BTX-A (experimental group), or normal saline (control group). Outcome measures:

The primary outcome measure will be pain as measured on a ten point Numeric Rating Scale with a two point reduction considered significant. Secondary outcomes will be paresthesias as measured on a Numeric Rating Scale, function measured on the Disabilities of the arm, shoulder and hand (DASH) questionnaire.

Study Timeline

• Study First Submitted: 2011-06-23
• Status Verified: 2011-07
• Study First Submitted QC: 2011-07-28
• Last Update Submitted: 2011-07-28
• Study First Posted: 2011-07-29
• Last Update Posted: 2011-07-29
• Study Start: 2011-08
• Primary Completion: 2012-12
• Study Completion: 2013-06

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 60

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 three months and less than two year
• 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 four 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 and 4 months
• Any abnormalities on EMG, CT or MRI studies suggesting an alternate diagnosis
• Pregnancy or planned pregnancy within six months

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Normal Saline	Normal Saline injection	Double-blind, randomized, placebo-controlled trial evaluating changes in pain, paresthesias, and function in subjects with TOS before, at six weeks, and four months following injection of placebo into the scalene muscles under EMG guidance.
Botulinum Toxin Type A injection	Botulinum Toxin Type A	Double-blind, randomized, placebo-controlled trial evaluating changes in pain, paresthesias, and function in subjects with TOS before, at six weeks, and four months following injection of BTX-A into the scalene muscles and pectoralis minor muscle under EMG guidance.

Primary Outcome Measures

Name	Time	Method
Pain	Change from baseline at six weeks and four months	The primary outcome measure will be change in baseline pain as measured on a ten point Numeric Scale and will be assessed at six weeks and four months following injection.

Secondary Outcome Measures

Name	Time	Method
Paresthesias on Numeric Rating Scale	Change from baseline at six weeks and four months	Secondary outcomes will be change from baseline in paresthesias as measured on a Numeric Rating Scale at baseline, six weeks and four months.
Function on DASH scale	change from baseline at 6 weeks and 4 monthss	Secondary outcome will be change from baseline in function on the Disabilities of the arm, shoulder, hand questionnaire at six weeks and at four months.

Trial Locations

Locations (1)

G F Strong Rehabilitation Centre; 🇨🇦 Vancouver, British Columbia, Canada