Correlation between shoulder radiographic parameters and supraspinatus tendon tear : acromio-tuberosity index (ATI) and acromio-tuberosity difference (ATD)

Abstract

The purpose of this study was to find the correlation between supraspinatus tendon (SSP) tear, ATI and ATD. A case-control study design was conducted in 182 patients who presenting with history of shoulder pain for more than 6 months of duration. ATI and ATD were measured on neutral anteroposterior position of conventional radiographs. SSP integrity was evaluated on MRI. The study consisted of 143 patients with SSP tear and 39 patients with no SSP tear. The median ATI of SSP tear group and no SSP tear group were 1.1 ± 0.1 and 1.2 ± 0.1 respectively. The median ATD of SSP tear group and no SSP tear group were 2.3 ± 2.2 mm and 4.3 ± 1.6 mm respectively. The result showed that ATI and ATD had good correlation for SSP tear on MRI in patient with shoulder pain(Area under curve = 0.748 and 0.746 for ATI and ATD respectively). Bursal side tear group also had lowest ATI and ATD compare to other tear pattern groups. Although results are statistically significant such a small difference, these emphasized their role as risk factors and concordance to rotator cuff pathogenesis described in previous studies.