Influence of Radiographic Bone Quality on the Type of Proximal Humerus Fracture

Background. The risk of proximal humerus fractures increases with age and deterioration of bone quality over time, and the treatment of these injuries may be clinically challenging.The aim of this study was to analyse the relationship between local bone quality and the morphology of proximal humerus fractures. Material and methods. We conducted a retrospective study of 187 patients diagnosed with proximal humerus fractures. X-ray images of all patients were analysed, and on this basis, bone quality was assessed, using the Deltoid Tuberosity Index (DTI), average cortical bone thickness (CBTavg) and the Tingart measurement. The type of fracture was classified according to Neer’s and Association for Osteosynthesis (AO) classifications. Moreover, the caput-collum-diaphyseal (CCD) angle was measured and the relationships between valgus or varus fractures and the DTI, CBTAVG and Tingart parameters were investigated in all patients. Results. Using the Neer classification, the most common fracture type was type 3, found in 90 patients (48.1%). A total of 51 patients (27.3%) sustained an AO B1 fracture. Significantly lower mean DTI values were noted in patients with a Neer 4 fracture compared to those with Neer 3 (p = 0.02) and Neer 2 fractures (p = 0.03). Moreover, significantly higher mean DTI (p <0.00) and CBTAVG (p <0.025) values were noted in the group of patients with valgus fractures (CCD> 140º). Conclusions. 1. In the group of patients diagnosed with a four-part fracture according to Neer, bone quality assessed using the Deltoid Tuberosity Index was significantly worse than in two- and three-part fractures. 2. Significantly higher bone quality, assessed on the basis of the DTI and CBTAVG indices, was observed among patients with valgus fractures compared to those with varus fractures.