Cervical Spine Thrust Joint Manipulation for Temporomandibular Disorder
Condition: Temporomandibular Disorder
MeSH terms: Temporomandibular Joint Disorders; Temporomandibular Joint Dysfunction Syndrome
Study type: Interventional

Summary: 
      Background: Temporomandibular disorder (TMD) is a common and costly problem that often leads
      to chronic pain or dysfunction. There is moderate evidence to support physical therapy (PT)
      interventions for individuals with TMD, yet they continue to be an underserved population. A
      known relationship between TMD and the cervical spine exists with some evidence to support
      the use of cervical interventions for TMD. Cervical spine thrust joint manipulation (TJM) is
      an effective PT intervention that has been explored in a limited fashion for this population.

      The purpose of this trial is to determine the immediate and short term (1 and 4 week) effects
      of cervical TJM delivered by a physical therapist on pain, dysfunction, and perception of
      change in persons with a primary complaint of TMD. The hypothesis is that all participants
      will improve, and those in the cervical TJM group may have a greater degree of improvement.

      Design: Participants will be randomized to one of two groups and all will receive physical
      therapy. Forty-two willing participants, age 18-65 with TMD will complete the informed
      consent process and screening for eligibility before being admitted. Participants will
      receive a combined treatment of 1) behavioral education, a home exercise program, soft tissue
      mobilization, and cervical spine TJM or 2) behavioral education, a home exercise program,
      soft tissue mobilization, and sham manipulation. Participants will receive 4 treatments over
      a period of 4 weeks.

      Significance: The results of this clinical trial will provide evidence relative to the impact
      of cervical spine TJM in the treatment of persons with TMD. Determining the effectiveness of
      cervical spine TJM included with a combined treatment approach has clinical implication for
      physical therapists and the patients they serve.
    

Detailed description: 
      Methods: Research design following CONSORT guidelines. A blinded assessor will measure ROM
      and PPT. Treating therapists will know group allocation and will receive training to
      standardize assessments and treatments. Self-report and objective measurements will be taken
      at baseline, immediately after treatment one, and at one and four week follow-ups.

      Data Analysis (primary): Sample size estimations were completed using G-Power, a free online
      downloadable program. An F-test family with ANOVA: Repeated measures, within-between
      interaction protocol was selected. While it is optimal to power sample size estimations
      around a functional outcome measure, the limited use of functional measures in this
      population created an obstacle. The sample size estimation for this project was powered
      around maximal mouth opening (MMO) as this most closely relates to function in the TMD
      population. In order to account for 15% attrition, and maintain equal participants in each
      arm of this study, the desired sample size is 42 participants.

      A 2 x 4 mixed model analysis of variance (ANOVA) will be used with treatment group as the
      between-subjects factor and time as the within-subjects factor. Separate ANOVAs will be
      performed for dependent variables and the hypothesis of interest will be group by time
      interaction for each ANOVA.

      To determine if missing data points associated with dropouts were missing at random or
      missing for systematic reasons, we will perform Little's Missing Completely at Random (MCAR)
      Test. Intention to treat analysis will be performed by using expectation maximization whereby
      missing data are computed using regression equations. Planned pair-wise comparisons will
      examine the difference between baseline and follow-up periods using the Bonferroni equality
      at an alpha level of 0.05.

      Success will be dichotomized using the GROC scale. A cut-off score of +5 or higher on the
      GROC will be used as a measure of success. Correlations between outcome measures (change
      scores) and success will be analyzed using an independent t-test to determine if differences
      between groups exist. Number needed to treat (NNT) will be calculated. Correlations among
      dependent variables will be analyzed with Pearson/Spearman correlations. Examples include the
      following: correlation between NDI and jaw functional measures, correlation among PPT at
      various areas tested, and correlation between change in ROM and change in functional scores.
      Data analysis will include 95% confidence intervals, and tables, charts, or other figures
      will be utilized to display findings to enhance reader understanding. Effect size of primary
      outcome measures including jaw ROM, JFLS, and TMD Disability Index will be calculated and
      reported. If there is no significant difference between groups noted, a post-hoc power
      analysis will be performed to determine the risk of Type II error.

      Data Safety Plan/Subject Confidentiality: The PI will be responsible for educating all
      clinicians, research assistants, and front office staff with RVPT, Bradley University, and
      UNLV in confidentiality measures and data safety plans. This information will be part of the
      live training and included in the Manuals of Standard Operating Procedures. The PI will also
      periodically check in with each participating clinician, blinded assessor, and clinic office
      staff member to review procedures and monitor recruitment and retention. This check will
      occur once per month over the phone.

      Standard Operating Procedures: Manual developed and used in training.
    

Intervention name(s): Cervical Spine Thrust Joint Manipulation; Cervical Spine Sham Manipulation; Home Program; Suboccipital Release
Intervention type(s): Other; Other; Other; Other
Intervention description(s): High velocity, short amplitude thrust to the cervical spine; Manipulative hold position shy of end range without a thrust; therapeutic exercise program and education; suboccipital soft tissue mobilization
Other intervention name(s): Grade V manipulation; soft tissue mobilization
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Participants will be randomly assigned to one of two intervention groups. Both will receive intervention and one group will receive cervical spine thrust joint manipulation while the other receives sham manipulation.
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Temporomandibular joint; Physical Therapy; Cervical spine thrust joint manipulation; therapy, exercise; Temporomandibular Disorders