The results of this review demonstrate that tests do exist that change the probability of the disc or SIJ ( but not the facet joint ) as the source of low back pain .
Clinical practice guidelines state that the tissue source of low back pain can not be specified in the majority of patients .
However , there has been no systematic review of the accuracy of diagnostic tests used to identify the source of low back pain .
The aim of this systematic review was therefore to determine the diagnostic accuracy of tests available to clinicians to identify the disc , facet joint or sacroiliac joint ( SIJ ) as the source of low back pain .
Clinical predictors of screening lumbar zygapophyseal joint blocks: development of clinical prediction rules.
BACKGROUND Only controlled intra-articular zygapophyseal joint ( ZJ ) injections or medial branch blocks can diagnose ZJ-mediated low back pain . The low prevalence of ZJ pain implies that identification of clinical predictors of a positive response to a screening block is needed . PURPOSE To estimate the predictive power of clinical findings in relation to pain reduction after screening ZJ blocks . STUDY DESIGN As part of a wider prospect i ve blinded study investigating diagnostic accuracy of clinical variables , a secondary analysis was carried out to seek evidence of variables potentially valuable as predictors of screening ZJ block outcomes . PATIENT SAMPLE Chronic low back pain patients received screening ZJ blocks ( n=151 ) with 120 patients included in the analysis after exclusions . OUTCOME MEASURES Pain intensity was measured using a 100-mm visual analog scale , and responses were categorized according to 75 % through 95 % or more pain reduction in 5 % increments . METHODS Patients completed pain drawings , question naires , and a clinical examination before screening lumbar ZJ blocks . History , demographic and clinical variables were evaluated in cross tabulation and regression analyses with diagnostic accuracy values calculated for variables and variable clusters in relation to different pain reduction st and ards . RESULTS At the 75 % pain reduction st and ard , 24.5 % responded to screening ZJ blocks and 10.8 % responded at the 95 % st and ard . The central ization phenomenon is not associated with pain reduction using any st and ard . No variables were useful predictors of post-ZJ block pain reduction of less than 90 % . Seven clinical findings were associated with 95 % pain reduction after blocks . Five useful clinical prediction rules ( CPRs ) were found for ruling out a 95 % pain reduction ( 100 % sensitivity ) , and one CPR had a likelihood ratio of 9.7 , producing a fivefold improvement in posttest probability . CONCLUSIONS A negative extension rotation test , the central ization phenomenon , and four CPRs effectively rule out pain ablation after screening ZJ block . One CPR generates a fivefold improvement in posttest probability of a negative or positive response to ZJ block
The results of this review demonstrate that tests do exist that change the probability of the disc or SIJ ( but not the facet joint ) as the source of low back pain .
Clinical practice guidelines state that the tissue source of low back pain can not be specified in the majority of patients .
However , there has been no systematic review of the accuracy of diagnostic tests used to identify the source of low back pain .
The aim of this systematic review was therefore to determine the diagnostic accuracy of tests available to clinicians to identify the disc , facet joint or sacroiliac joint ( SIJ ) as the source of low back pain .