Reliability of Inclinometer-Derived Passive Range of Motion Measures in Youth with Cerebral Palsy

Aims: This study evaluated, for youth with cerebral palsy (CP), the reliability of passive range of motion (PROM) measures taken with an inclinometer, a device that may be simpler to use than a goniometer. Methods: The PROM for elbow and wrist extension, ankle dorsal flexion (knee flexed 90 degrees and fully extended), and the knee popliteal angle of 30 youth with CP (18 boys, 12 girls, 7.0 +/- 3.8 years old, classified in Gross Motor Function Classification levels I-V) was measured using an inclinometer. Two physical therapists took the measures during two different sessions, a maximum of 1 week apart. Results: Good mean intra-rater inter-session, inter-rater intra-session, and inter-rater inter-session reliability (ICC = 0.75-0.89), was found for the elbow, ankle, and knee sites. Absolute reliability for these sites and conditions was 7-14 degrees (90% confident) and 10-16 degrees (95% confident). Reliability values for wrist extension were comparable, albeit slight lower. Conclusions: Similar to published values for goniometry, inclinometery yields reliable upper and lower limb PROM measures from ambulatory and non-ambulatory youth with CP whether measures are carried out by different evaluators within or across sessions or whether measures are performed by the same evaluator across sessions.