This week features a 2-part guest post discussing the McKenzie Method of Mechanical Diagnosis and Therapy (MDT) by Christie Downing. Christie is a frequent contributor to this site. I think this is a great series to “clear the air” about some of the misconceptions regarding MDT, and more importantly, to share some of Christie’s experience and pearls of wisdom. If you are unfamiliar with MDT, take this as an opportunity to get to learn more about the method. While Christie discusses that MDT is not all about extension exercises, it does fit into my reverse posturing theory to an extent.
The McKenzie Method – Clearing the Air
What is your gut reaction when you hear “McKenzie Method?” I predict you are either excited or just rolled your eyes. If it is the later, I hope you will give this post due diligence. For it is my observation that those who despise it have not been fully informed about it. It’s one of the most researched physical therapy approaches, yet is fraught with misconceptions. For those interested in the research, the McKenzie Institute International maintains a database of the most relevant research. However, rather than discuss the literature, my objective will be to clear up misconceptions of what the McKenzie method entails and to give some brief “Pearls of Wisdom.” This first post will entail a brief overview of the McKenzie Method, otherwise known as Mechanical Diagnosis and Therapy (or MDT).
Mechanical Diagnosis and Therapy – MDT
Due to long standing misconceptions, much has been inaccurately portrayed regarding MDT. When describing MDT to another practitioner, it is sometimes easier to first discuss what it is not. MDT is/does not:
- A series of exercises
- Only about derangement
- Only extension
- Only about the intervetebral disc
- Only about repeated end range movements
- Ignore biopsychosocial issues
- Without the use of manual therapy
- Only about spinal conditions
I will address each of these issues point by point to more accurately portray what MDT is:
MDT is not a series of exercises: Although some exercises are common, MDT is an assessment process and problem solving paradigm. One takes clues from the history about the effects of specific loading strategies on one’s symptoms. At the history, the therapist begins to formulate a differential diagnosis. First, is it a problem with a mechanical influence, a medical influence, a biopsychosocial influence or any combination of the above? Second, if mechanical, which of the syndromes are likely at play: derangement, dysfunction, posture or “other?” Then, the examination includes a series of loading strategies to confirm or refute the postulated diagnosis.
MDT is not only about derangement: Although found widely, derangement syndrome is not the holy grail of MDT. Muscular or articular restrictions (dysfunctions) and postural syndromes are part of the “main” three mechanical syndromes. However, stenosis, chronic pain state (i.e., centrally/periperhally sensitized pain), SIJ dysfunctions, s/p traumatic states, etc. are all recognized by MDT clinicians.
MDT is not just extension: Although a common treatment recommendation, all planes of movement can be considered in both the assessment and treatment recommendations.
MDT is not just about repeated end range movements: static positioning and mid range movements are all part of the spectrum of force progressions.
MDT is not just about the intervertebral disc: Although it serves as one model of joint derangement, other postulated mechanisms are frequently discussed including: joint inclusions, fat pads, loose bodies, capsular impingements, etc for both the spine and peripheral joints as applicable.
MDT does not ignore biopsychosocial influences: Although a positive mechanical response (such as centralization) can sometimes trump “yellow flag” indicators, fear avoidance behaviors and other biopsychosocial influences are always considered and dealt with by education and graded exposure to movement where necessary.
MDT does not exclude manual therapy: Although we take a “hands off” approach first, mobilization and manipulation are all part of the continuum of force progressions. We focus primarily on education and self directed treatments first in order to reduce dependency and empower the patient to control their symptoms; however, sometimes patients are not successful in reducing their own pain in the initial stages. It is at this time we consider the use of our hands. However, use our hands in order to foster greater success of the patient treating themselves. We put our hands on, only to take them off again.
MDT is not just about the spine: The concepts of assessment and classification can be applied to the peripheral joints as well.
As a brief summary, MDT is a classification system. It seeks to differentiate between mechanical and non-mechanical influences of pain and functional limitation by using mechanical loading strategies and assessing both the patient’s subjective response and any mechanical changes.
The main 3 mechanical syndromes are derangement, dysfunction and postural syndromes.
Although the intervertebral disc serves as one model for mechanical influences of spinal pain, other influences are recognized. MDT focuses on patient education and empowerment in order to promote self directed treatment, reduce fear, and promote function. In part 2 of this series, we will describe the syndromes in more detail and offer “Pearls of Wisdom.”
Thanks Christie, great post! One thing that I wanted to also mention was a book that you can read for more information, Rapidly Reversible Low Back Pain. The book has been discussed here in the past, is a quick read, and I think is pretty cheap (~$10) on Amazon. I thought it did a good job talking about MDT, including it’s origin. My favorite story was the discovery of extension exercises for low back pain, check it out if haven’t already.
Have you heard these misconceptions? Did this post surprise you? What other questions do you have about what MDT is?
Christie Downing, PT, DPT, Dip. MDT, ICLM Christie works at Alexian Brothers Rehabilitation Hospital in Elk Grove Village, IL. She specialize in musculoskeletal care as well as lymphedema management. She is a MDT credentialed provider and student in the Diploma level of MDT, focusing primarily in MDT in both spine and extremity problems.
Photo credit toyourhealth