By Corey Kim, MPT | Registered Physiotherapist, Certified in Mechanical Diagnosis and Therapy (Cert. MDT)
Published January 26 2023 [Last Updated September 17 2026]
I started out in my career very eager to learn physiotherapy as a craft, so I've taken a lot of courses over the years. Most of what I've learned has provided great value to my clients, but there's one thing that helps the majority of them and delivers long-term value: the McKenzie Method of Mechanical Diagnosis and Therapy. I've since gone on to become fully certified in MDT through the Robin McKenzie Institute of Canada, and I use these principles throughout my treatment of the spine and extremities.
What is it?
The McKenzie Method of Mechanical Diagnosis and Therapy (MDT) is a way to find the source of your problem through repeated movements and objective testing. An exciting part of this treatment is the potential to rapidly reverse your condition — this includes rapidly changing your range of motion, decreasing your pain and accelerating your return to the activities you love. One of the other great things about MDT is that I can teach you how to maintain your progress and prevent the same injury from happening again in the future.
Does this sound like you? The "mystery injury"
If you've been injured before, you may have experienced a lingering issue that doesn't resolve over time. After several attempts at self-care through massage and stretching, you can't seem to find relief. You've ignored it, and over time it's gradually worsened. You may have tried various health care practitioners who provide temporary relief, but nothing that lasts.
Whether your injury is recent or chronic, this kind of "mystery injury" doesn't improve with time. Certain activities can be painful one day and fine the next. As the intensity of pain fluctuates, it prevents you from moving well. Worst of all, it's invisible — no one else can see it, only you can feel it. Pain is isolating and confusing. How do you make sense of it all?
Here are some signs that MDT-guided physiotherapy might be right for you:
Your improvement is variable and not consistent
It's difficult to understand your pain and what you can do to change it
You don't have concrete ways of testing your improvement
Conventional stretching and strengthening programs aren't helping
You want to find the actual source of your problem
You've tried other types of physiotherapy, chiropractic or massage with no real change
Enter MDT
MDT is a systematic approach that helps make sense of complex injuries. Using an algorithmic approach, MDT narrows down the source of the injury. It uses movement and pain patterns to determine the exact movement required to reduce pain and improve function — and it's backed by a substantial body of research.
To help make sense of whether MDT is right for you, here's an example:
Sue is a 61-year-old woman with right hip pain during her daily hikes with her walking group. Her stride has changed, and it hurts to put weight on her right leg. Her pain fluctuates — some days she feels great, other days are very painful. Massage and stretching haven't helped. After several weeks and months, frustration sets in. She seeks help from her family physician, who suspects arthritis and orders an x-ray of her hip. To her surprise, the x-ray comes back normal. She's confused, because the source of her pain isn't clear. Her doctor suggests she try physiotherapy.
Many of my clients come in with this same confusion — the imaging doesn't line up with the injury. So where is the pain actually coming from?
Pain referral
Pain referral is a bit like an ice cream headache — the ice cream touches your palate, but you feel a deep chill in your brain. Different parts of the body can refer pain to other locations. When Sue came to see me, we explored the possibility that her hip pain was actually referred from elsewhere. With further investigation, we found the source was her lower back.
It sounds surprising, but there's good research on the spine being a source of pain in other locations. One study separated patients by where they were experiencing pain and found that for those reporting hip pain, 71% could change their symptoms by moving the lower back.
How we check the lower back: repeated movements
Clinicians trained in MDT repeat a movement to gain a better understanding of your injury — asking about the location and intensity of pain, testing the strength of muscles around the area, and measuring range of motion.
Going back to Sue: when I assessed her, we completed 20 repetitions of cobra (lumbar extension), holding for 2 seconds at the top of the stretch. Afterwards, her hip range of motion and strength increased. She reported that walking became easier, her stride felt longer, and putting weight on her right leg hurt less. We found that sitting in a slouched position would worsen her hip range of motion and decrease her strength, so we corrected this with a posture roll in her lower back for driving. Her hip no longer hurt randomly when hiking, and she became consistently pain-free.
Sue was then able to return to her regular activities with a program to maintain what she'd gained — understanding that her posture mattered when driving, and that regular stretching would help prevent the injury from returning.
Why it works so well
It uses the scientific method. Test, treat, retest. We use range of motion, strength, or your ability to perform a task in clinic as a baseline, then give you a movement to repeat and check whether it made you better. Simple but effective.
It's collaborative and centered around you. You're not just relying on a physiotherapist to apply a treatment — we work together as a team to find the source of your problem. Without your input, it's much harder to help you reach your goal. It becomes a dialogue centered on what matters most to you.
There's strong evidence behind it. MDT is one of the most researched treatment methodologies out there, and some of the largest studies point toward the spine being the culprit behind a lot of arm and leg problems — with real statistics on what percentage of those problems may be coming from the spine.
It's a framework for ruling out serious problems. MDT helps categorize your problem into different subgroups. Based on how you describe your problem and how you move in clinic, we can determine whether physiotherapy is the right path or whether you need to see a specialist. If we can't help, we'll do our best to help you find someone who can.
It lowers your chance of reinjury. "Give someone a fish and they'll eat for a day. Teach someone to fish and you feed them for a lifetime." MDT is built to help you manage your problem on your own. Once you've learned the tools, if the problem resurfaces, you know how to address it — and if you keep up with your maintenance program at home, there's a good chance you'll stay pain-free for a long time.
Could it be coming from your spine?
You've probably heard the saying "the human body is all connected." There's a real chance your pain could be coming from your spine rather than the area where you feel it — but it's hard to know unless we test it thoroughly.
Here are some questions worth asking yourself:
Do your symptoms worsen or improve with changes in posture?
Do your symptoms worsen when sitting, bending, turning, or staying still?
Have you lost range of motion in your spine — for example, you used to be able to bend forward and touch your toes, but can't anymore?
Do you experience tingling, numbness, or pins and needles?
If you answered yes to any of these, there's a higher chance your injury is related to your spine.
Final thoughts
I love seeing people get better — it's genuinely one of the best parts of this work. My goal is to help people break free from their injuries long-term so they can get back to living fully. There are moments where we find a rapidly reversible problem through repeated movements, and my clients look at me with wide eyes, somewhere between bewilderment and excitement. It still gets me every time.
A lot of my clients joke that it feels like magic — which always reminds me of that line from Harry Potter: "Yer a wizard, Harry!"
If you want to find out whether you have a rapidly reversible condition, and whether MDT could work for you, book an assessment or call the clinic at 519-850-3733.
If you're curious about how centralization and peripheralization — two key concepts within MDT — relate to your specific back, neck, or leg pain, check out our companion post on that topic.
For more on MDT itself, you can also visit the Robin McKenzie Institute Canada.
