The value of the acromiohumeral distance in the diagnosis and treatment decisions of patients with shoulder pain: A retrospective case-control study

Abstract Background : The role of subacromial space reduction in causing shoulder pain / rotator cuff tears (RCTs) remains controversial. It is widely thought that extending the acromiohumeral distance (AHD) by subacromial decompression provides limited relief of shoulder pain. Herein, we assessed the differences in AHD between patients with shoulder pain treated with or without surgery and analyzed whether there was a linear relationship between AHD and Constant-Murley shoulder joint function score (CMS) and severity of RCTs. Methods: A retrospective case-control study included patients from our hospital from 2019 to 2022 divided into surgical treatment (n=93) and non-surgical treatment (n=116) groups. The two groups were comparable in age, gender, and location of shoulder pain. Data, including the degree of RCTs, CMS, and AHD, were recorded. The Mann-Whitney U test was used to compare differences between groups in AHD, RCTs, and CMSs. Pearson correlation analysis was used to represent the correlation between AHD and CMS. Spearman correlation analysis was used for the correlation between AHD and RCTs grade and CMS and RCTs grade. Results : AHD was smaller in the surgery group than the non-surgery group, but the difference was not statistically significant (P>0.05). The CMS of the surgical group was significantly lower than the non-surgical group (P<0.001). The degree of RCTs was significantly more severe in the surgery group than in the non-surgery group (P<0.001). Pearson correlation analysis between AHD and CMS showed a weak or no correlation(P>0.05). Spearman correlation analysis showed a significant correlation between CMS and RCTs (P<0.001). However, no significant difference was found between AHD and RCTs (P = 0.797). Conclusions: Our results suggest that surgical or non-surgical management of patiens with shoulder pain or RCTs should focus on shoulder joint function and degree of rotator cuff tears, and a potential decrease in subacromial space/AHD has minimal value.