Osteoporotic fractures of the proximal humerus: Assessment, implications on surgery and project for a novel device of fracture fixation.

Background:Hypothesis of this study is that osteoporotic proximal humerus fractures show different fracture patterns respect to non-osteoporotic, and that assessment of some proposed osteoporotic characteristics is reliable and reproducible between shoulder surgeons. The objectives are: a) to identify osteoporotic proximal humerus fractures in a large consecutive series of patients; b) to analyze fracture patterns among osteoporotic and non-osteoporotic proximal humerus fractures; and c) to calculate intra- and inter-observer reliability of assessment of osteoporosis and of characteristics of osteoporotic proximal humerus fractures. Methods:This is a prospective observational study of patients admitted in emergency department with a diagnosis of proximal humerus fracture (Current Procedural Terminology code 812.00) between June 2014/2016. Demographic data, comorbidities, x-rays and CT-scans were studied by three shoulder surgeons, two times per each. Evaluation of osteoporosis with an original method was assessed; then, specific characteristics of osteoporotic fractures were studied. Intra- and inter-tester reliability were calculated. Results:220 patients with 225 proximal humerus fractures were available. 163/225 (72.4%) fractures were identified as osteoporotic fractures. The intra-observer agreement of the proposed method was 0.83; the inter-observer 0.84. Specific osteoporotic fracture characteristics were Codman-Hertel type 12(p=0.041), metaphyseal comminution(p<0.001), impaction of fragments(p=0.023), comminution of tuberosities(p=0.037), inferior subluxation(p=0.029). Intra- and inter-tester reliability for evaluation of these characteristics were high. Conclusions:Osteoporosis of the proximal humerus was identified in ¾ of a two-year survey population group using a simple and reliable method; most of these fracture were of elderly female patients sustaining low energy trauma. These fractures show specific patterns, as comminution of metaphysis and of tuberosities, impaction of fragments, and inferior subluxation of the humeral head.