Reliability of the Modified-Modified Schöber and Double Inclinometer Methods for Measuring Lumbar Flexion and Extension

BACKGROUND AND PURPOSE: The primary purpose of this study was to determine the reliability of lumbar flexion and extension range-of-motion measurements obtained with the modified-modified Schöber and the double inclinometer methods on subjects with low back pain. SUBJECTS: Fifteen patients (8 women, 7 men), aged 25 to 53 years (mean = 35.7, SD = 9.9), with chronic low back pain were measured by three physical therapists with 3 to 12 years (mean = 8.3, SD = 4.7) of clinical experience. METHODS: The therapists used the modified-modified Schöber and double inclinometer techniques to measure, in random order and on two occasions, the subjects' lumbar flexion and extension. RESULTS: Pearson Product-Moment Correlation Coefficients for test-retest reliability for the modified-modified Schöber technique varied from .78 to .89 for lumbar flexion and from .69 to .91 for extension; for the double inclinometer method, Pearson correlation coefficients varied from .13 to .87 for lumbar flexion and from .28 to .66 for extension. Analysis of variance-derived intraclass correlation coefficients for interrater reliability for the modified-modified Schöber technique were .72 for flexion and .76 for extension; for the double inclinometer technique, they were .60 for flexion and .48 for extension. CONCLUSION AND DISCUSSION: The modified-modified Schöber method thus appears to be a reliable method for measuring lumbar flexion and extension for patients with low back pain, whereas the double inclinometer technique needs improvement.