Determination of the False Positive Rate of Uncontrolled Diagnostic Block for Lumbar Medial Branch of Dorsal Rami.
10.4097/kjae.1999.37.5.859
- Author:
Jae Chol SHIM
1
;
Dong Won KIM
Author Information
1. Department of Anesthesiology, College of Medicine, Hanyang University.
- Publication Type:Original Article
- Keywords:
Nerve, nerve block, medial branch of dorsal rami block;
Pain, low back pain, zygapophysial joint pain
- MeSH:
Arthralgia;
Back Pain;
Bupivacaine;
Diagnosis;
Humans;
Joints;
Lidocaine;
Low Back Pain;
Prospective Studies
- From:Korean Journal of Anesthesiology
1999;37(5):859-866
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Patients without genuine zygapophysial joint pain exhibit a positive response to uncontrolled diagnostic blocks. We determined the false positive rate of single uncontrolled diagnostic zygapophysial joint block in patients with chronic back pain. METHOD: Thirty-five patients with chronic lower back pain were studied prospectively. All patients underwent a series of medial branch of dorsal rami blocks with lidocaine and bupivacaine starting at the symptomatic level to a maximum of three levels or until the pain was abolished. RESULTS: All patients proceeded with the injections. 16 patients (45%) had a definite or greater response to the initial lidocaine injection at one or more levels but only 5 (14%) had a 50% or greater response to a confirmatory injection of 0.5% bupivacaine. Using the confirmatory blocks as the criterion standard, the false positive rate of uncontrolled diagnostic blocks was 37% and the positive predictive value was only 31%. CONCLUSION: Uncontrolled diagnostic blocks may be unreliable for the diagnosis of lumbar zygapophysial joint pain.
