38
F
Dec
2018
Feature
Examining the evidence
Mulling
muscle
relaxants
A patient presenting with acute low
back pain poses a treatment dilemma
Clinical scenario
HARRY, a 55-year-old hospital cleaner, saw me
with acute low back pain after lifting a heavy
bag of linen. I recalled reading that skeletal
muscle relaxants might be helpful in acute low
back pain. Another of my patients had been
prescribed orphenadrine citrate in the emergency
department for the same indication. It’s one of
the few non-benzodiazepine muscle relaxants
available in Australia. I wondered if this would
be a good option for Harry. What is the evidence?
Clinical question
What is the effect of oral orphenadrine citrate
on acute low back pain recovery?
What does the research evidence say?
Step 1: The Cochrane Library
A rather old Cochrane systematic review
published in 2003 exists for the question of
muscle relaxants for low back pain. 1 Although
this review suggested that non-benzodiazepines
may be effective, most of the included trials
used other agents, and the few that used
orphenadrine were decades old
and problematic.
Step 2: TripDatabase
I conducted a search using the TripDatabase
PICO search tool (Participant: “low back
pain”, Intervention: “orphenadrine”,
Minimal clinically
important difference
THE minimal clinically important
difference is a patient-centred concept
that defines the “smallest amount
an outcome must change to be
meaningful to patients”. 7
When looking at study results, it is
not enough that a difference between
groups exist (statistically significant,
or otherwise), but whether it is of
sufficient magnitude to be important.