Intrarater Agreement of Elbow Extension Range of Motion in the Upper Limb Neurodynamic Test 1 Using a Smartphone Application

Abstract

Objective: To estimate the intrarater agreement of the Compass application of a smartphone in the assessment of elbow extension range of motion (EE-ROM) at pain onset and maximum tolerable point during the Upper Limb Neurodynamic Test 1 (ULNT1).

Design: Within-day intrarater agreement study.

Setting: Private and university clinical settings.

Participants: Volunteers (N=41; 21 men; age, 31.34±13.27y; height, 1.67±0.07m; body mass, 70.53±12.37kg) recruited from the community, with no symptoms or musculoskeletal abnormalities in their upper body quadrant and no regional or systemic nerve dysfunction.

Interventions: Not applicable.

Main outcome measures: Ninety-five percent limits of agreement (LOA), standard error of the measurement, and minimal detectable change at the 95% confidence level (MDC₉₅) of EE-ROM at pain onset and maximum tolerable point during the ULNT1.

Results: Standard error of the measurement and MDC₉₅ were relatively high on both sides when considering the onset of pain (standard error of the measurement, 6.6°-6.8°; MDC₉₅, 18.4°-18.8°). Better results were found for the maximum tolerable point (standard error of the measurement, 4.2°-4.8°; MDC₉₅, 11.7°-13.2°). The 95% LOA showed a similar trend.

Conclusions: Smartphone measurements showed relatively wide agreement parameters of elbow extension during the ULNT1. These results are, nevertheless, comparable with previous studies using goniometric assessment when considering maximal pain tolerance. Further research is needed before the possible widespread use of the smartphone in neurodynamic assessment.

Trial registration: ClinicalTrials.gov NCT02159924.

Keywords: Observer variation; Pain threshold; Peripheral nerves; Rehabilitation.