Here is a great case example of a patient that I saw recently to understand the beauty and simplicity of the MDT system of assessment and diagnosis created by the late Robin McKenzie.
MDT is first and foremost a classification system. One of the strengths of MDT is the assessment system, and this system is not focused on presumed patho-antomy. Decision making is based on symptomatic and mechanical responses to repeated movements and loading strategies and is focused on education and self-management tailored to the unique patient in front of you.
Referred to me by an experienced Sports Physician with the comment that the “Patients weakness is disproportionate to the MRI finding. Please assess further for potential spine/hip/SIJ cause to the loss of power”.
MRI right hip demonstrates mild gluteus medius tendinosis, partial tearing of the gluteus minimus with mild trochanteric bursal oedema.
A lovely lady in her mid-50’s with a sitting/driving job.
Symptoms came on after a fall over in an exercise class. Also had rib pain and broken ribs which resolved.
Timeframe now > 1year and patient reports them as unchanging.
Symptoms are all intermittent: Right sacral, lateral hip/thigh.
Symptoms are mild, and biggest complaint is huge loss of power and inability to walk up stairs (requiring a side-ways crab type method of getting up/down).
Pain is consistently produced on the stairs at a very mild level, despite marked loss of power.
Lying on the right side for > 10 mins also produces right sacral and hip symptoms.
What about psychosocial factors I hear you say??!
The patient reveals no fear to move her back or hip during the physical examination.
Yellow Flag Risk Form score at intake of 68.
Recommended YFRF cut off scores:
- Low risk of CNS characteristics – under 50 points
- Moderate risk of CNS characteristics – 50-65 points
- High risk of CNS characteristics – over 65 points
Low self-reported scores on the anxiety and depression domains (3/10 for both).
Moderate-high scores on the fear avoidance questions (eg 8/10 for I should not do my normal activity due to pain).
What MDT classifications are possible from the history?
There are many and rather than going through a detailed reasoning of the which/why (which would be only fully understood by those with MDT training, and I wanted to expose this case study to a broader reach) here are some of candidates (not the only options):
- Lumbar derangement (ie referral from the lumbar spine, and by definition rapidly changeable once exercises are performed in the directional preference)
- Hip derangement (ie referral from the hip joint, and by definition rapidly changeable once exercises are performed in the directional preference)
- SIJ derangement (less likely potentially given symptom distribution in the lateral thigh)
- Contractile (eg tendon pathology which should behave consistently with load)
- Hip articular dysfunction (eg hip OA)
- Chronic pain syndrome
The key physical exam findings
Functional baselines: (all volunteered by the patient upon enquiring about “can you show me things you can’t do because of your problem”)
- Significant difficulty stair climbing and weight bearing on right leg (note minimal pain in right sacrum/lateral thigh)
- Patient volunteered and showed me inability to hop on right leg due to power (no pain)
- Unable to perform right single leg glute bridge (and clearly able to on left, mild pain only reproduced)
Hip range of motion testing:
- Mild loss of right hip flexion (active and passive similar, and left full and painless)
- Moderate loss of right her ER (20 degrees, not painful, compared to L=45)
- Mild loss of right hip IR (5 degrees producing right buttock pain, L= 10)
- Full hip extension
Resisted muscle testing:
- Weakness with resisted right hip abduction in lying (4/5)
- Unable to do right single leg glute bridge (mild buttock pain) or hop (pain free)
- Standing hip hitch on step decreased power on right ++
Lumbar Spine range of motion (ROM) testing:
Moderate loss of lumbar extension (no pain)
Minimal loss of lumbar flexion (no pain)
Mild loss of lateral movements both side (no pain)
The brilliance and simplicity of MDT!
This is the big one where MDT excels in differentiating between multiple competing diagnoses/classification used repeated movement testing or sustained positions (over 1 or multiple sessions until a classification is reached):
Step 1- Rule the lumbar spine in/out by proving that it does/does not affect our local joint functional baselines and ROM tests
Repeated lumbar extension in lying (with sag/breath out to achieve end-range or close to it via patient generated forces) x 40 reps was assessed.
(note: Extension was chosen as the first direction to test given the movement loss was moderate, and the patient has a predominantly sitting/driving job which involves sustained lumbar flexion. Testing repeated lumbar flexion would have been potentially equally as valid/useful an option).
No change on hip functional baselines. Increased lumbar ROM, slight increase right hip ER.
Step 2- Further lumbar testing would have been reasonable (and we could always come back to this) but given the lack of any change at all to the hip baselines of stair-climbing, hopping and single leg glute-bridge the hip joint was assessed with repeated movements.
Repeated hip flexion was chosen first. It would have been valid to test various directions including external rotation (ER) given it was the biggest movement loss at the hip. Usually it is preferable to keep it simple and stick in the sagittal plane first.
After repeated hip flexion x 30 reps.
- Stair climbing around 60% better (not explained by a contractile/tendon problem)
- Single leg hop now possible but weak
- Single leg glute bridge now possible but weak
- Increase in hip ROM with flexion (now close to full) and ER (increase to 35)
Repeated hip extension x 20 now assessed.
- Worse with all functional baselines, back to similar at initial testing
- Worse with hip ROM, back to similar at initial testing
Provisional classification: Hip derangement with a directional preference for flexion. Plan for patient to perform hip flexion in lying (or sitting as more practical with her work, and this was testing for a suitable symptomatic/mechanical response) x 20-30 reps every few hours.
*Note- had lumbar repeated movement testing and hip repeated movement testing failed to change our functional baselines, MDT would not have failed. It would however helped further refine our remaining potential classifications and assist ruling in/out remaining classifications like hip contractile structures (this would not explain the hip loss of ROM or sacral symptom).
What happened at follow up?
The response to hip flexion was confirmed at the next session. The exercises were refined including applying more force, ensuring they were performed correctly and regularly.
The patient improved by 70-80% over a 1-2-week period.
Interestingly the ability to lie on the right side did not resolve despite rapid changes in power, all functional baselines and hip ROM increasing.
Over sessions 2-3 a plateau was reached. So, what now?
Further hip repeated movement testing revealed that addition of external rotation with the hip flexion fully cleared all mechanical signs and symptoms in the room including all power testing.
Classification: Hip derangement with a directional preference for flexion, with a relevant lateral component of external rotation.
The only remaining complaint by the patient…
Still unable to lie on the right side at night (but notes lower right sacral pain and no longer any right lateral hip pain).
So now what?
The lumbar spine was reassessed with repeated movements.
I asked the patient to lie on the right side for 5 mins (her reported time in bed for the onset of symptoms).
At 4 mins and 55 seconds the patient reported the right sacral pain, which increased the longer she lay there (acknowledged: the surface was different to her bed).
Repeated extension in lying as reexamined (tested at initial and did increase all lumbar ROM but was not further explored given the lack of any change to hip baseline functional tests in any way).
Patient now able to lie for close to 7 mins for any symptoms felt. Testing at home over 48 hours found resolution of the night pain.
Classification: Secondary problem of lumbar derangement with a directional preference for extension.
Key messages to take from this case study:
- The patient had a complex history and it was not obvious which diagnosis/classification she had.
- The MDT process quickly and inexpensively found a solution and differentiated between potential competing diagnoses/classifications through a simple yet rigorous assess process
- The patient was actively involved in her own care with both the assessment (volunteering the functional baselines when asked) and in the solution (self-generated exercises that provided relief and restored power/movement).
- This scenario is not uncommon for those who assess/test patients with MDT and who have sufficient training in the system
- The testing of movement in the opposite direction to the directional preference (eg hip extension repeated movement testing) rapidly worsened all hip functional baselines/ROM and would reduce the likelihood of a placebo response given this finding. This was useful to confirm the classification and helped reduce fear as the patient could rapidly reverse this worsening situation.
Written By Senior Physiotherapist & MDT Diplomat Joel Laing