Study on Shoulder Joint Parameters and Available Supraspinatus Outlet Area Using Three-Dimensional Computed Tomography Reconstruction

Studies addressing the anatomical values of the supraspinatus outlet area (SOA) and the available supraspinatus outlet area (ASOA) are insufficient. This study focused on precisely measuring the SOA and ASOA values in a sample from the Chinese population using 3D CT (computed tomography) reconstruction. We analyzed CT imaging of 96 normal patients (59 males and 37 females) who underwent shoulder examinations in a hospital between 2011 and 2021. The SOA, ASOA, acromiohumeral distance (AHD), coracohumeral distance (CHD), coracoacromial arch radius (CAR), and humeral head radius (HHR) were estimated, and statistical correlation analyses were performed. There were significant sex differences observed in SOA (men: 957.62 +/- 158.66 mm(2); women: 735.87 +/- 95.86 mm(2)) and ASOA (men: 661.35 +/- 104.88 mm(2); women: 511.49 +/- 69.26 mm(2)), CHD (men: 11.22 +/- 2.24 mm; women: 9.23 +/- 1.35 mm), CAR (men: 37.18 +/- 2.70 mm; women: 33.04 +/- 3.15 mm), and HHR (men: 22.65 +/- 1.44 mm; women: 20.53 +/- 0.95 mm). Additionally, both SOA and ASOA showed positive and linear correlations with AHD, CHD, CAR, and HHR (R: 0.304-0.494, all p < 0.05). This study provides physiologic reference values of SOA and ASOA in the Chinese population, highlighting the sex differences and the correlations with shoulder anatomical parameters.