Based on the relationship between Hounsfield units and bone mineral density: a tool for preoperative planning of rotator cuff tears

Purpose: To quantify the abnormal bone mass of the proximal humerus using the Hounsfield unit (HU) to assist in preparing preoperative surgical plan and improve the curative effect. Methods We identified patients who underwent computed tomography and dual-energy X-ray absorptiometry (DXA). The proximal humerus HU values and DXA results were recorded, the correlation of HU and BMD was calculated, and the diagnostic effect was evaluated. Results A total of 600 proximal humeri (389 patients) were included in the study. There was no significant difference in the HU values between shoulders (t = 0.62, p = 0.536). The HU values of the humeral head and the greater and lesser tuberosity were negatively correlated with age, but positively correlated with BMD (p < 0.001). We have obtained the exact cut-off value of HU values. All the cut-off values had good diagnostic values, and the area under the curve (AUC) was more significant than 0.70. The linear regression equations of HU values and T score were obtained. Conclusion The HU value of CT is an excellent method to evaluate the bone mass of the proximal humerus. We obtained threshold values of abnormal BMD of the humerus head, greater tuberosity, and lesser tuberosity, which can be used to assist in selecting anchors during ARCR and improve the curative effect.