Botulinum Toxin Versus Placebo Injections to Temporalis and Masseter Muscles
Condition: Pain, Head; Pain Syndrome; Temporomandibular Disorder; Myofascial Pain Syndrome; Myofascial Pain
MeSH terms: Myofascial Pain Syndromes; Temporomandibular Joint Disorders; Temporomandibular Joint Dysfunction Syndrome; Fibromyalgia; Syndrome; Headache; Somatoform Disorders
Intervention: Botulinum toxin type A; 0.9% Sodium Chloride Injection
Intervention description: 37.5 units injected into each masseter muscle and 12.5 units into each temporalis muscle; 1cc syringe
Intervention MeSH terms: Botulinum Toxins; Botulinum Toxins, Type A; abobotulinumtoxinA
Phase: Phase 3
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Study participants will be randomly allocated to one of two treatment arms (injection of botulinum versus placebo). Blocked randomization will be performed at each of the participating sites. They will be stratified based on study site.
Masking: Triple (Participant, Care Provider, Investigator)
Masking description: Randomization will be carried out by the biostatistics team at Weill Cornell. This will provide assurance that there will be equal patient allocation to both study arms, at each participating site, in the event that the target sample size is not reached. The list will be maintained by the investigational pharmacy. A designated research assistant will be identified at each site to prepare the interventional medication (botulinum versus normal saline). The identity of the agent injected will be unknown to the surgeon as the agent will be drawn up by an assistant in a masked syringe immediately prior to each procedure and labeled with the patient's identifier. Only one assistant at each site will know the identity of the agents during the trial.
Enrollment: 75.0
Sex: All
Minimum age: 18 Years
Maximum age: 65 Years
Healthy volunteers: No
Keywords: Myofascial Pain; Myofascial Pain Disorder; Maxillofacial Pain; Masseter Muscle; Temporalis Muscle; Botulinum Toxin

Summary:

      This study aims to determine whether the injection of botulinum toxin A or placebo
      (unpreserved 0.9% sodium chloride) into the masseter and temporalis muscles provides pain
      relief and improved jaw function in those who suffer from myofascial pain disorder. The study
      hypothesis is that botulinum toxin A injection is superior to placebo. The specific research
      questions are:

        1. Is the injection of botulinum toxin A superior to placebo for the improvement in pain?

        2. Is the injection of botulinum toxin A superior to placebo for the improvement in
           function or quality of life (QOL)?

        3. Are there any adverse effects that result from injection of botulinum toxin A or placebo
           into the masseters and temporalis muscles? Limited data exists to support the use of
           botulinum toxin A in the management of myofascial pain disorder of the masticatory
           region. Botulinum toxin A is not FDA approved for intra-muscular injection within the
           masticatory region. Its use in the masticatory region is considered off-label but
           performed without significant known complications. This study will provide the
           opportunity to quantitate and qualitate any complications in a large prospective sample
           of patients.
    

Eligibility criteria:

        Inclusion Criteria:

          -  18-65 years of age

          -  Ability to give informed consent

          -  Myofascial pain of masticatory muscles as defined according to the RDC/TMD criteria

          -  Baseline pain measured by the subject ≥3.5/10 on visual analog scale

        Exclusion Criteria:

          -  Baseline pain measured by the subject <3.5/10 on visual analog scale

          -  Central/Neuropathic pain disorder affecting the masticatory muscles

          -  Temporomandibular Joint Arthralgia that is more severe than the myofascial pain
             disorder affecting the masticatory muscles

          -  Previous Temporomandibular Joint Surgery

          -  Systemic arthropathies

          -  Fibromyalgia

          -  Allergy to study medications

          -  Traumatic injury of masticatory muscles or temporomandibular joint within last 12
             months

          -  Mandibular fracture within last 12 months

          -  Pregnancy or breast feeding

          -  Cervical radiculopathy or surgery

          -  Prior botox injection in the masticatory muscles

          -  Initiation of additional treatment of MPD within the past 3 months