Test-retest reliability of joint position sense in the elbow among healthy adults

Proprioception of the elbow is necessary for daily activities. Proprioception can be impaired with injury or pathology, and rehabilitation efforts seek to improve proprioception for improved upper extremity functioning. In clinical practice, joint position sense (JPS) testing is often utilized to assess conscious proprioception; however, varying methods exist with little evidence of psychometric properties, especially for the elbow.

The primary aim of this study was to create a standardized elbow JPS test protocol using goniometry measurement to determine the most reliable testing position. The secondary aim was to determine if the elbow JPS test had acceptable test-retest reliability in healthy adults.

This was a cross-sectional study using a convenience sample of healthy adults.

Three elbow positions (45°, 60°, and 75° of elbow flexion) were measured twice on the same day by a single rater using a universal goniometer. We calculated the absolute error in degrees between each position and reposition and the intraclass correlation coefficient (3,1) for relative reliability. We also calculated the standard error of the measurement and visually inspected Bland-Altman plots for absolute reliability.

Sixty-eight healthy adults (mean age 27.9 years, standard deviation 8.59) were assessed. The mean absolute error for all positions for test and retest was 5.7°. The intraclass correlation coefficients were moderate to good (0.57-0.75), and the standard error of the measurement was 2° (rounded) for all positions. The limits of agreement were moderately narrow, and the Bland-Altman plots showed a random distribution of errors for each position, indicating clinically acceptable measurement error.

The joint position reproduction test for JPS using goniometry demonstrated moderate to good test-retest reliability and acceptable measurement error in healthy adults. The elbow joint angle of 60° flexion was the most reliable for JPS testing, providing insight for JPS assessment in clinical practice.