Shoulder and elbow joint position sense assessment using a mobile app in subjects with and without shoulder pain - between-days reliability.

OBJECTIVES: To determine between-days reliability and the minimal detectable change for shoulder and elbow joint position sense assessment using a validated mobile app, in subjects with and without shoulder pain. DESIGN: Reliability study. SETTING: Clinical measurement. PARTICIPANTS: Subjects with (n = 25) and without shoulder pain (n = 29). MAIN OUTCOME MEASURES: Subjects were assessed by the same examiner in two sessions, with one-week interval. Active joint repositioning tests of shoulder flexion and scaption and elbow flexion were assessed at the target-angles of 50°, 70°, 90° and 110°. Intra-class correlation coefficient, standard error of measurement and minimal detectable change were calculated for constant, absolute, total and variable errors. RESULTS: Good to excellent reliability was found for constant, absolute and total errors at the target-angle of 50° of scaption for healthy subjects; at 110° of shoulder flexion and all target-angles for elbow for both groups. CONCLUSIONS: The mobile app is a reliable tool and may be useful for assessing shoulder joint position sense mainly at 110° of flexion and for elbow between 50° and 110° of flexion in subjects with and without shoulder pain. Minimal detectable changes were demonstrated and may help clinicians to follow-up rehabilitation and researchers to interpret findings of studies.