Assessment of the Effect of Botulinum Toxin in Extensor Digitorum Brevis Via Strain Gauge and Nerve Conduction Studies
Condition: Muscle Strength; Botulinum Toxins, Type A
Study type: Interventional

Summary: 
      The purpose of this feasibility study is to determine if temporary weakness of a small foot
      muscle caused by local injection of botulinum toxin into that muscle can be measured with a
      strain gauge in addition to the previously known valid measurements via nerve conduction
      studies and surface electromyogram.
    

Detailed description: 
      Purpose/Hypothesis:

      Verify the validity and reliability of strain gauge assessment of strength of extensor
      digitorum brevis (EDB) muscle compared to compound muscle action potential (CMAP) size from
      EDB and surface electromyography (SEMG) data from EDB after injection of botulinum toxin into
      EDB

        1. Primary Outcome Measure:

           Change in measured strength (using strain gauges) of dorsiflexion of digits 3 and 4
           ("strength of EDB") after vs. before botulinum toxin injection into EDB

        2. Secondary Outcome Measures:

             1. Change in CMAP (with standard reference electrode location and with an "inactive"
                reference electrode location) from EDB after vs. before botulinum toxin injection
                into EDB;

             2. Change in SEMG parameters from EDB, tibialis anterior (TA), and extensor digitorum
                longus (EDL) after vs. before botulinum toxin injection into EDB

      STUDY DESIGN:

        1. Overview:

           Single intramuscular injection of botulinum toxin or placebo (placebo or BOTOX 2 units
           or BOTOX 20 units, each with a total volume of 0.1 ml) intramuscular into right EDB on
           Day 0. Strain gauge data and SEMG data from TA and EDL are obtained at each evaluation
           time: Baseline (3 separate times prior to Day 0 after at least 5 separate training
           sessions for the strain gauges); Day 1; Day 2; Day 4 (during anticipated rapid change);
           Day 14 (+/-1 day) (at clinical nadir); Day 21 (+/-1 day) (another day at clinical
           nadir); and Month 4 (when clinical recovery from the effect of BOTOX should have
           occurred); CMAP & SEMG data from EDB are obtained at Baseline; Day 4 (close to nadir of
           CAMP); Day 14 (at nadir of CAMP) and/or Day 21 (at nadir of CAMP); and Month 4 (when
           clinical recovery from the effect of BOTOX should have occurred but CMAP should not have
           recovered).

        2. Protocol:

      Single-center, Double-Blind, Randomized, Pilot Trial Total Sample Size: 12-15

      Treatment Groups:

      BOTOX Single Dose 20 units IM in EDB in 0.1 ml BOTOX Single Dose 2 units IM in EDB in 0.1 ml
      Placebo (Saline) Single Dose IM in EDB in 0.1 ml

      Estimated Time to Enroll:

      0-3 months

      Estimated Study Duration:

      4-6 months
    

Intervention name(s): Botulinum Toxin, Type A; Botulinum Toxin, Type A; Saline
Intervention type(s): Drug; Drug; Drug
Intervention description(s): 20 units, single dose, intramuscular in right EDB muscle; 2 units, single dose, intramuscular to right EDB muscle; Single Dose, Intramuscular into right EDB muscle
Other intervention name(s): BOTOX; BOTOX; Placebo
Intervention MeSH terms: Botulinum Toxins; Botulinum Toxins, Type A; abobotulinumtoxinA
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Diagnostic