Laser-Pointer assisted angle reproduction test (LP-ART): reliability, performance, and correlation with shoulder pain and disability in patients with subacromial pain syndrome

Physiother Theory Pract. 2022 Feb 8;1-10. doi: 10.1080/09593985.2022.2035031. Online ahead of print.


Introduction: The proprioception plays an important role in the stability of the shoulder joint. However, clinical practice lacks reliable and user-friendly tools.

Objectives: To evaluate the intra- and inter-rater reliability of the Laser-Pointer assisted Angle Reproduction Test (LP-ART), to analyze the difference in proprioception between the symptomatic and asymptomatic shoulders, and to investigate if there is a correlation between the LP-ART and the pain intensity assessed by 11-point Numerical Rating Pain Scale (NRPS) and the level of shoulder disability and pain assessed by the Disability Index and Shoulder Pain (SPADI - BR).

Methods: Fifty patients (age = 56.2 ± 10.4 years) performed the LP-ART at 90° of shoulder flexion.

Results: The intra and interrater reliability of the LP-ART measurements was moderate (Intraclass Correlation Coefficient2,3 = 0.41 to 0.65) for both shoulders, symptomatic and asymptomatic. There was no difference in the absolute angular deviation between shoulders (mean difference of 0.4°, P = .581). The absolute angular deviation was not significantly correlated with the pain intensity (rs = 0.007, P = .962) and the SPADI - BR (rs = 0.022, P = .881).

Conclusion: The LP-ART measurement showed moderate reliability in participants with subacromial pain syndrome. The active joint position sense was not different between symptomatic and asymptomatic shoulders, and there was no correlation between proprioception and the pain intensity and shoulder pain and disability level.

Keywords: Proprioception; observer variation; reproducibility of results; shoulder joint.