Pressure Pain Threshold in Subjects with Piriformis Syndrome: Test-Retest, Intra-, and Inter-Rater Reliability, and Minimal Detectible Changes

Publication date: Available online 7 December 2019

Source: Archives of Physical Medicine and Rehabilitation

Author(s): Abbas Tabatabaiee, Ismail Ebrahimi Takamjani, Javad Sarrafzadeh, Reza Salehi, Maryam Ahmadi.

Abstract

Objective

This study aimed to assess the test-retest, intra-, and interrater reliability of using the pressure pain threshold (PPT) in healthy and affected piriformis muscles and to estimate its absolute reliability. As a secondary objective, the degree of tenderness of the affected piriformis muscles was compared with healthy piriformis muscles.

Study Design

This study used a comparative and reliability-based design.

Setting

Rehabilitation clinic.

Participants

Thirty patients with unilateral piriformis muscle syndrome (30 affected and 30 healthy piriformis muscles) were recruited, and the PPT of both the healthy and affected piriformis muscles was recorded using digital algometry. Measurements of PPT were done by two raters (rater 1 and 2), which have selected at random order. The rater 1 repeated the PPT measurements 24-72 hours after initial assessment.

Interventions

Not applicable.

Main Outcome Measures

PPT.

Results

Excellent intra-rater intra-class coefficient (ICC) values were observed for the PPT of the affected piriformis (ICC: 0.86–0.96) and the healthy piriformis (ICC: 0.88–0.96) in the same session. The PPT measurements using digital algometry showed good-to-excellent inter-rater reliability (ICC: 0.64–0.92) and test-retest reliability (ICC: 0.72–0.95) in both the healthy and affected piriformis muscles. The findings revealed a significant decrease in the PPT of the affected piriformis muscle in comparison to the healthy piriformis muscle (mean difference 12.76 [95% confidence interval [CI]:15.69–9.82], P < 0.001).

Conclusion

Digital algometry is a reliable tool for measuring piriformis PPT, regardless of the testing session and the rater. Patients with unilateral piriformis muscle syndrome have increased tenderness and decreased PPT in the affected piriformis muscle in comparison to the healthy piriformis muscle.

from ScienceDirect Publication: Archives of Physical Medicine and Rehabilitation https://ift.tt/34VEoeq
via IFTTT