Limitations of evidence-based treatment and research in manipulative therapy

In an ideal world treatment decisions would be based on the evidence revealed by clinical trials. However, many variables affect accurate determinations of cause and effect in arthro-neuro-muscular dis­orders. The validity of clinical trials in the manual therapies is confounded by many factors.

  • Valid measurement tools for manual interventions have not yet been developed.
  • There are few inter- and intra-rater reliability studies for manual techniques.
  • All too often a manual therapy novice performs the manual techniques in a research study.  This will impact both the selection of technique and research outcomes. Master practitioners who have studied and practiced over many years will likely administer more effective interventions than would a student. I encourage experienced manual therapists to collaborate with clinical researchers to make meaningful contributions to the body of knowledge of manipulative therapy.
  • There are difficulties in the development of accurate and meaningful functional diagnoses and assessment measures to monitor changes in patient response and upon which to interpret findings.
  • Research results are unreliable when studies do not differentiate various techniques. Not all manual mobilization and manipulation techniques are the same. Research reports should provide a detailed description of the techniques used, including:
    • The precise position of the patient and the targeted joint. For example, research results using mobilization and manipulation techniques initiated from outside the resting position may not be applicable to Nordic OMT methods.
    • The speed and amplitude of the movement. For example, the term “manipulation” has been used by various authors to describe any type of treatment performed with the hands, from slow stretch mobilizations to manipulative thrusts. In the Nordic System, the term “manipulation” is reserved for small amplitude high velocity thrust techniques.
    • Whether the movement includes a traction component. Both Nordic System non-thrust mobilizations and manipulative thrusts include a traction component. Techniques used by others often do not.
    • Whether the movement is translatoric or rotatoric.
    • he precise direction of force.

There are an abundance of important and relevant questions worthy of study in manipulative medicine, including treatment outcomes and the cellular and soft tissue effects of manual therapy.