Digital mapping of shoulder pain in patients with shoulder disorders: a reliability study

ABSTRACT

Introduction

Digital body mapping can be used to document and quantify the area and location (distribution) of pain and discomfort and support assessment, monitoring, and treatment in clinical populations. This study determines the test–retest reliability of drawings detailing pain and pins and needles using digital body charts and their relationship to pain intensity and patient-reported shoulder function.

Methods

Sixty-two participants with shoulder disorder completed pain and pins and needles drawings with test–retest interval of 30 minutes. Pain intensity in the last week and the patient-reported shoulder function questionnaires were completed. Area and radiating extent were determined using customized software. To assess relative and absolute test–retest reliability, the intraclass correlation coefficient (ICC_3,1), standard error of measurement (SEM) and minimal detectable change (MDC₉₅) were calculated. Regression analysis evaluated relation between area and radiating extent of pain and pins and needles with patient-reported function questionnaires.

Results

Relative reliability for pain area and radiating extent was excellent (>0.90). Absolute reliability (SEM and MDC₉₅) values for the pain area and radiating extent were 0.20%/34 pixels and 0.57%/94 pixels. Absolute reliability improves for smaller pain areas. Regression analysis revealed the area and radiation extent for both pain and pins and needles are independent constructs to the patient-reported function outcome when adjusted for pain intensity.

Conclusions

Digital body mapping assessing pain area and radiation extent in patients with shoulder disorders are reliable. The magnitude of absolute reliability suggests other sources of variability on repeat testing in this population. Pain area and radiation extent appear to be independent constructs.

KEYWORDS:

• Pain drawings
• digital body mapping
• reliability
• shoulder disorders
• subacromial impingement
• frozen shoulder
• shoulder fracture

Acknowledgments

The authors would like to thank the students from University College Copenhagen who helped recruit patients and collect the pain drawing and questionnaire data. A sincere acknowledgement goes to the management and physical therapists working at the Centre of Rehabilitation, Nørrebro, City of Copenhagen, Denmark.

Disclosure statement

SAB is a co-developer of the Navigate pain android app (Aalborg University) used in this study and has holdings in Aglance Solutions ApS, which licenses a digital body mapping web application. All other authors declare that they have no competing interests.

Additional information

Funding

The author(s) reported that there is no funding associated with the work featured in this article.