Psychophysical measurements during lumbar discography: a heart rate response study.
METHODS
Prospective clinical data analysis.


OBJECTIVE
To determine if heart rate (HR) response correlates with positive discography results.


BACKGROUND
Lumbar discography is a controversial tool for the diagnosis of discogenic low back pain. The subjective nature of discography can make data interpretation difficult, leading to false-positive and false-negative results. HR changes have been found in numerous studies to be a reliable and valid indicator of acute pain. To date, there is no study analyzing the HR response to discography-induced pain.


METHODS
The HR measurements were recorded immediately preceding and after contrast injection into the each disc, and statistically correlated with the provocation of concordant pain, nonconcordant pain, and nonpainful discs.


RESULTS
Discography was performed in 26 subjects with low back pain. Among 75 discograms, 26 discs elicited concordant pain, 9 provoked nonconcordant pain, and 40 elicited no pain response. There was no significant change in HR during disc stimulation for negative [no pain response (P=0.19) and nonconcordant (P=0.26)] discograms, whereas positive discograms [concordant pain (numerical rating scale> or =6/10)] were associated with a statistically significant increase in HR (P=0.000002).


CONCLUSIONS
Lumbar discography induces positive HR response only in positive discograms. Although there is no immediate practical application of these results, 2 implications may deserve future research: (a) correlation of HR response with surgical and intradiscal electrotherapy treatment outcomes; (b) evaluation of HR measurement in cases of false-positive results (concordant pain on discography but no HR response).
Stojanovic
Milan P
MP
Interventional Pain Program, MGH Pain Center, Department of Anesthesia and Critical Care, Massachusetts General Hospital, Boston, MA 02114, USA. mstojanovic@partners.org
Cheng
Jianguo
J
Larkin
Thomas M
TM
Cohen
Steven P
SP
D000328:Adult; D001175:Arthrography / Q000009:adverse effects / Q000379:methods*; D003287:Contrast Media / Q000009:adverse effects; D004562:Electrocardiography; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D017116:Low Back Pain / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement / Q000009:adverse effects / Q000379:methods*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011601:Psychophysics / Q000379:methods; D015203:Reproducibility of Results; D013610:Tachycardia / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology
D003287:Contrast Media