title: New physical examination tests for lumbar spondylolisthesis and instability: low midline sill sign and interspinous gap change during lumbar flexion-extension motion.
abstract: BACKGROUND
  Lumbar spondylolisthesis (LS) and lumbar instability (LI) are common disorders in patients with low back or lumbar radicular pain. However, few physical examination tests for LS and LI have been reported. In the study described herein, new physical examination tests for LS and LI were devised and evaluated for their validity. The test for LS was designated "low midline sill sign", and that for LI was designated "interspinous gap change" during lumbar flexion-extension motion.
  
  
  METHODS
  The validity of the low midline sill sign was evaluated in 96 patients with low back or lumbar radicular pain. Validity of the interspinous gap change during lumbar flexion-extension motion was evaluated in 73 patients with low back or lumbar radicular pain. The sensitivity, specificity, and positive and negative predictive values of the two tests were also investigated.
  
  
  RESULTS
  The sensitivity and specificity of the low midline sill sign for LS were 81.3% and 89.1%, respectively. Positive and negative predictive values of the test were 78.8% and 90.5%, respectively. The sensitivity and specificity of the interspinous gap change test for LI were 82.2% and 60.7%, respectively. Positive and negative predictive values of the test were 77.1% and 68.0%, respectively.
  
  
  CONCLUSIONS
  The low midline sill sign and interspinous gap change tests are effective for the detection of LS and LI, and can be performed easily in an outpatient setting.
authors.affiliation: Ahnkang Pain Free Hospital, CHA University, 323 Nonhyeon-Ro, 135-930, Kangnam-Ku, Seoul, Republic of Korea. kangahn2003@gmail.com.
authors.forename: Kang
authors.initials: K
authors.lastname: Ahn
authors.affiliation: Ahnkang Pain Free Hospital, CHA University, 323 Nonhyeon-Ro, 135-930, Kangnam-Ku, Seoul, Republic of Korea. oemdoc21@gmail.com.
authors.forename: Hyung-Joon
authors.initials: HJ
authors.lastname: Jhun
mesh_terms: D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D017116:Low Back Pain / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010808:Physical Examination / Q000379:methods*; D011237:Predictive Value of Tests; D011859:Radiography; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D013168:Spondylolisthesis / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology