??? Clinical question: indications for MRI

[proud]

Having just recently read Timothy Flynn's clinical commentary in JOSPT regarding appropriate use of Diagnostic imaging in low back pain, I have a question.

In the commentary, reference is made to the American College of Physicians and the Americal Pain Society's clinical practice guidelines where indications for MRI are suggested.

One of them is "severe or progressive neurologic deficit"

How would you define that? I have a patient right now who has significant pain into his leg down to his foot. Although deep tendon reflexes are symmetrical, he has absent L5 myotome( great toe extension) and notably diminished L4 myotome (dorsiflexion).

The pain initially started 1st of January but the "weakness" is a new onset in the past week.

Would this fit the definition of progressive neurologic deficit?

[Jon Newman]

I think so.

[Barrett Dorko]

I agree with Jon.

What people fail to consider however is that the manifestations of a deficit over time vary wildly.

[Josh]

Yes, I agree, should obtain imaging. May not alter treatment, but will rule out bad stuff!

[ste5e]

Yes, this is precisely what the guidelines are looking for. Progressing neurological feature. If it was to extend to more than one level then you could have a red flag.

[Frédéric]

Are there any sensitive hypoesthesia in corresponding dermatomas?

What is the patient's age?

How about SLR, PKB and SLUMP tests results?

Any signs of red flags other than that? night pain? smoker? how about the second muscles in the myotomes, like the gluts or hamstrings?

My personnal opinion would be affected by all that. I am usually patient when the compression signs are only partial, weakness only for instance, as pain is notable for influencing strengh/motivation for efforts. I would give a few treatments and monitor neuro signs and neural tension tests every visit in the mean time.

[proud]

Originally Posted by Frédéric

Are there any sensitive hypoesthesia in corresponding dermatomas?

What is the patient's age?

How about SLR, PKB and SLUMP tests results?

Any signs of red flags other than that? night pain? smoker? how about the second muscles in the myotomes, like the gluts or hamstrings?

My personnal opinion would be affected by all that. I am usually patient when the compression signs are only partial, weakness only for instance, as pain is notable for influencing strengh/motivation for efforts. I would give a few treatments and monitor neuro signs and neural tension tests every visit in the mean time.

He is 35

+ve SLR at 40 degrees/+ve slump/did not check PKB

No red flags

Yes, I will be proceeding with a trial of 3-4 treatments to monitor

[nari]

I would give a few treatments and monitor neuro signs and neural tension tests every visit in the mean time.

I agree with this approach + PKB.

Nari

[advantage1]

If myotome or reflex do not improve or worsen I would consider this a progressively worsening neuro deficit. I don't think I would rely on SLR or dermatomes.

[Frédéric]

Originally Posted by advantage1

If myotome or reflex do not improve or worsen I would consider this a progressively worsening neuro deficit. I don't think I would rely on SLR or dermatomes.

I don't think we can rely on any specific sign in isolation. And I would consider a worsening over several treatment and not just one. Also, someone coming in with a positive myotome likely did have a negative myotome at some earlier point in his or her condition. Meaning he did worsen at some point but before seing the PT. Yet we should not send a patient with only a positive myotome, normal reflexes and normal dermatomes for an MRI or should we?

If the myotomes strenghts weakens over several treaments and hypoesthesia and hyporeflexia begins when it wasn't there in the first place I would be more inclined to an MRI, even more so if the deficits spreads to other nerve roots.

[Frédéric]

I have a patient currently who initially came in with only mildly hyporeflexive C6 reflexes, OK in myotomes and dermatomes. With trapeze pain, shoulder pain and thx pain. He was getting better until a fall on the ice. Re checked Neuro signs : positive dermatomes in the thumb C6, myotomes in elbow flexion and wrist extension. The neck moved well though and with little pain.

Saw the patient again this week and the myotomes are much better, the hypoesthesia has lessen also. Did not ask for an MRI. I think these are subject to variations so it's good to sample over a reasonnable time period.

[advantage1]

What is a midly hyporeflexive reflex? Seems subject to error and poor interrater reliability.

[Frédéric]

Originally Posted by advantage1

What is a midly hyporeflexive reflex? Seems subject to error and poor interrater reliability.

Well, bicipital reflex slightly less strong/lively on the right side (in french we say vif) and brachioradialis reflex also slightly less strong on R side. The feature was/is present every time on seperate dates. We'd have to check if the way we assess reflex is valid and reliable but I assume there is some decent/acceptable intra and inter rater reliability for reflex assessment given it's a commonly used measure to test neurological status. I don't know if you'd prefer I say 4/5 or 4+/5 but I find this probably more prone to intervariability thus the more subjective term employed : mildly. BTW it's not necessarily how I charted it.

Then again, it's not only the reflex I check because of SMD and variability in the measures but rather clusters of signs. So I always look at the overall portrait of dermatomes, myotomes and reflexes and if the signs all fit inside the distribution of one nerve root or if they are extra or multisegmental.