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The following is a summary of “Pressure Pain Sensitivity is Independent of Structural Pathology in Patients with Subacromial Pain Syndrome: A Cross-Sectional Analysis” published in the November 2024 issue of Pain by Pierson et al. 

Researchers conducted a retrospective study to compare localized (primary) and widespread (secondary) hyperalgesia using pressure pain threshold (PPT) in patients with normal imaging findings, rotator cuff tear, or other pathologies.  

They included participants with chronic subacromial pain syndrome lasting 3 months or more, categorizing them into 3 imaging groups: normal imaging, rotator cuff tear, or other structural pathology. Primary hyperalgesia was measured with PPT at the lateral deltoid of the painful shoulder, and secondary hyperalgesia was assessed at the contralateral tibialis anterior muscle (TA). An ANOVA and ANCOVA were used for analysis, with covariates including age, sex, education level, and pain duration.  

The results showed 103 participants, including 55 males, had a median age of 55 years, a median pain duration of 14.0 months, and a median Shoulder Pain and Disability Index (SPADI) score of 43.1%. The ANCOVA for primary hyperalgesia revealed no significant difference in square-root adjusted deltoid PPT across imaging groups (F = 1.04, P = 0.3589) and the ANCOVA for secondary hyperalgesia also showed no significant difference in log-adjusted TA PPT between imaging groups (F = 0.24, P = 0.7900).  

Investigators concluded no significant differences in PPT were observed between patients with different structural shoulder pathologies, suggesting that the pathologies were not associated with differences in a measure of hyperalgesia. 

Source: academic.oup.com/painmedicine/advance-article-abstract/doi/10.1093/pm/pnae123/7908992