Inter- and intraexaminer reliability of a single, digital inclinometric range of motion measurement technique in the assessment of lumbar range of motion.

Objective: The between and within examiner reliability of a range of motion digital inclinometer was evaluated for lumbar flexion, extension and right and left lateral flexion.

Design: Blinded, lumbar range of motion instrumentation reliability.

Setting: Private college research and ambulatory patient care facility.

Participants: Twenty-eight asymptomatic persons recruited from a private college. This included students, staff and faculty that ranged from 23-36 yr, with no history of back pain or surgery or back injury 6 wk prior to entry into the study.

Intervention: Lumbar range of motion examination, twice by each examiner, or four times in all per subject.

Main Outcome Measure: Lumbar range of motion, measured in degrees.

Results: Intraclass correlation (ICC) revealed lack of reliability for this device except flexion, but intrinsic limitations of the instrument suggests that flexion as well may not be reliable. The p value of .05 was used for statistical significance and Burdock's recommended value of .75 represented the minimum R value for reliability.

Conclusion: Most of the reliability values did not meet Burdock's recommended minimum R value, and the R values for flexion may have met minimum criteria due to intrinsic limitations of the instrument itself. Due to the findings of this study, we conclude that the Orthoranger II digital inclinometer is not reliable, between and/or within examiners, for measuring lumbar flexion, extension or lateral flexion. Because there was evidence to suggest other variables which were not accounted for, and which could have affected final results, the development of a streamlined protocol may result in more consistent findings. Further research is needed to either support or dispute these results before this instrument can be recommended as an assessment tool in clinical practice or in clinical trials.