Lumbar range of motion: influence of time of day and individual factors on measurements.

STUDY DESIGN: Influence of time of day and individual factors on the measurements of the lumbar range of motion was investigated.

OBJECTIVES: To investigate factors that influence lumbar range of motion.

SUMMARY OF BACKGROUND DATA: Twenty-nine patients with chronic low back pain participated in the study.

METHODS: The lumbar range of motion was measured by inclinometer technique, Schober sign, modified-Schober sign, and fingertip-to-floor method in the morning, at noon, and in the afternoon. The lumbar range of motion was correlated with patients' gender, age, and body weight.

RESULTS: Total lumbar range of motion measured by the inclinometer technique and the modified-Schober sign increased significantly throughout the day from morning to afternoon. Extension lumbar range of motion was shown to be independent of the time of measurement. There were no significant correlations between lumbar range of motion and gender, age, and body weight of the patients.

CONCLUSION: For the reliability of a measurement, it is important to investigate lumbar range of motion at the same time of day.