Dr David McGrath

Spine Physician

MB BS (Hons) FAFOM, RACP, FAFMM
Master of Pain Medicine

This is an interseting subject,which goes into the heart of our biology. It is also of great practical interest. Let's start with the maths.

DiagnosisOutcome	Good Result	Bad Result
Explanation Right	a	b
Explanation Wrong	c	d

The "a" cell indicates that the diagnosis is correct and a good outcome has occured
The "b" cell indicates that the diagnosis is also correct,but the outcome was poor
The "c" cell indicates that the diagnosis was incorrect but a good outcome occured nonetheless
The "d" cell indicates that the diagnosis was incorrect and a bad outcome occured

In other words, we have come to expect cells "a" and "d". The problem lies with cells "c" and "b".
Cell "c" is an unexpected bonus and is relatively common. Cell "d" is what we definately don't want.
We can state treatments fail because
1.Despite a correct diagnosis, the treatment was insufficient or incorrectly applied (cell b)
2.An incorrect diagnosis was made, with inappropriate treatment and poor outcome(cell d)

The other side of the coin is:
1.Good diagnosis, good treatment and outcome (cell a )
2.Bad diagnosis, bad treatment, good outcome (cell c)

All of these possibilities are thought to be relatively common in spinal medicine.

Some concrete examples.

1.Diagnosis=You have hurt your disc. Treatment =manipulation. Outcome =good. Most likely the situation is "c". The diagnosis of "hurt disc" is difficult to make and often wrong. The treatment is unlikely to apply. The outcome is good because of the correct diagnosis=minor strain and the confounding treatment of natural recovery.
2.Diagnosis=Spondylolitheseis. Treatment=spinal exercise. Outcome =bad. The most likely situation is "b". The structural explanation from spinal imaging is usually accurate. The correct set of spinal exercise can be difficult to establish which leads to a bad outcome.
3.Diagnosis= Prolapsed disc with severe nerve involvement. Treatment = surgical decompression. Outcome=good. The most likely situation is "a".
4.Diagnosis is muscle weakness. Treatment=strenghening. Outcome=bad. The most likely situation is "d". The diagnosis is wrong. The correct diagnosis might be internal disc disease, which has a different treatment protocol needed for a good outcome.

In some ways the situation of cell "c" is the biggest problem. We are diagnising incorrectly and obtaining a good result from reasons unrelated to the treatment. This leads to great confusion in the minds of medical advisors and patients alike. But cell "b" is also a bother. We have not established the best treatments with precision for each correct diagnosis.

In other words, the reason treatments WORK is just as important as why they FAIL.

In the real world, patients wander from treatment to treatment looking for an answer. They can become lost in a sea of confusion. Recursive neuromodulation or the experimental movement approach obviates some of this difficulty by NOT seeking a specific diagnosis but rather an ordered set which can expand into further order. This is not a risky enterprise, once important treatable diagnosis have been excluded. (eg cancer,infection)