Reliability of the lumbar flexion, lumbar extension, and passive straight leg raise test in normal populations embedded within a complete physical examination

Study Design. The study measured the reliability of the passive straight leg raise (SLR) test and lumbar range of motion (LROM) tests measured as continuous variables embedded within a comprehensive physical examination. Objectives. To determine the reliability of the SLR and LROM test scores when they are measured with a Cybex electronic inclinometer (Lumex, Inc., New York, NY) within a physical examination. Summary of Background Data. Good published empirical reliability exists for the Cybex and for SLR and LROM tests when the measurements are taken in isolation from other physical examination procedures. Reliability of the Cybex for continuous SLR and LROM measurement within a physical examination has not been assessed, however. Methods. Forty-five participants were seen by one of two physician/physiotherapist teams, Participants were examined by both team members. The first examiner conducted the first tests and retested 1 week later (intrarater reliability). The second examined the participants the day after their first appointment (inter-rater reliability). Results. Only two scores showed substantial reliability (defined as r > 0.60). These scores were left (r = 0.81) and right (r = 0.79) SLR intrarater reliability. All other scores fell below the specified cutoff. Conclusions. SLR and LROM scores used clinically are collected during comprehensive physical examinations. Most scores gathered under these conditions were not reliable. These findings have implications for the use of clinically derived SLR and LROM scores.