The utility of the discogram in diagnosing of the painful discs remains controversial. We performed discography with computed tomogram and evaluated the relationship between volume, pressure resistance, pain response and discs morphology..
The results of discogram of 72 discs were reviewed retrospectively. All patients had chronic back pain unresponsive to conservative measures. Discogram were performed by one examiner using the same method subjectively documenting pain
response(PR),
pressure(P) immediately after penetration of the nucleus and then prior to removal(Low, High), volum(V) of Iohexol in ml and immediately followed by biplanar X-ray and computed tomogram(CT) scan. A positive pain response was defined as Grade III
or
IV.
Discogram morphology was classified into 5 Types, Type I being a normal appearing disc and Type V showing greater than 60% degeneration. Reviewers of X-ray studies were blined to the clinical data and those reviewing the clinical data were
unaware
of
the morphology.
In general a trend of increasing pressure is evident as disruption worsens. When a subgroup of discs with a low-to-high pressure response in disc morphology Type IV and V was examined separately 30 of 34 level, 88%, were pain response positive.
The
subgroup high-to-high had a distinctive immediate pain response positive in 6 of 9, 67%, positve responders.
The results of this study may increase the predicability of a positive pain response and elucidate the possibility of different pain mechanism in disc pathology.
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