Article

OBJECTIVE: To evaluate the predictive utility of the pattern of low back pain
(LBP) in detecting the source of LBP as internal disk disruption (IDD), facet
joint pain (FJP), or sacroiliac joint pain (SIJP). DESIGN: Retrospective chart
review. SETTING: University spine center. PATIENT SAMPLE: A total of 170 cases
from 156 patients presenting with LBP whose low back disorder was definitively
diagnosed. The mean age was 54.4 years (SD, 16.2) and median duration of LBP was
12 months (interquartile ranges, 6-32). METHODS: Charts of consecutive LBP
patients who underwent definitive diagnostic spinal procedures including
provocation diskography, facet joint blocks, and sacroiliac joint blocks were
retrospectively reviewed. Each patient with LBP was queried as to the exact
location of their LBP: midline, defined as in-line with the spinous processes,
and/or paramidline, defined as lateral to 1 fingerbreadth adjacent to the
midline. OUTCOME MEASURES: In patients with a definitive diagnosis for the source
of LBP, the proportion of each diagnosed source of pain was calculated. chi(2)
tests were used to identify differences in the percentages of midline and
paramidline LBP among the groups of patients testing positive for IDD, FJP, or
SIJP. Diagnostic measures of sensitivity, specificity, positive and negative
predictive values, diagnostic accuracy, and likelihood ratios of positive and
negative tests using the presence/absence of midline and paramidline pain for the
diagnosis of IDD, FJP, and SIJP were estimated. RESULTS: With cases of IDD,
significantly greater percentages of patients reported midline LBP (95.8%; chi(2)
= 101.4, df = 2, P < .0001) as compared with cases of FJP (15.4%) or SIJP
(12.9%). In cases of IDD, significantly lower percentages of patients reported
paramidline pain (67.3%; chi(2) = 16.1, df = 2, P = .0003) as compared with cases
of FJP (95.0%) or SIJ (96.0%). In cases of IDD, significantly greater percentages
of patients reported midline LBP (95.8%; chi(2) = 101.4, df = 2, P < .0001) as
compared with cases of FJP (15.4%) or SIJP (12.9%). The specificity of midline
LBP for IDD, FJP, and SIJP was 74.8% (95% CI = 65.0%-82.9%), 28.0% (20.1%-37.0%),
and 36.0% (28.0%-44.5%), respectively. The negative predictive value of
paramidline LBP for IDD, FJP, and SIJP was 29.2% (95% CI = 12.6%-51.1%), 91.7%
(73.0%-99.0%), and 95.8% (78.9%-99.9%). The diagnostic accuracy of midline LBP
for IDD, FJP, and SIJP was 83.5%, 24.1%, and 31.8%, respectively. CONCLUSIONS:
The presence of midline LBP increases the probability of lumbar IDD and reduces
the probability of symptomatic FJ and SIJ dysfunction. The presence of isolated
paramidline LBP increases the probability of symptomatic FJ or SIJ but mildly
reduces the likelihood of lumbar IDD.
CI - Copyright A(c) 2011 American Academy of Physical Medicine and Rehabilitation.
Published by Elsevier Inc. All rights reserved.

Langue : ANGLAIS