Objective: To predict the risk of osteonecrosis (ON) according to the Neer and Hertel et al. classification for surgically treated proximal humeral fractures after at least one year of follow-up. Methods: This is a retrospective, cross-sectional, and observational cohort study. A total of 44 patients, 16 (36.36%) men and 28 (63.63%) women, with a mean age of 61.36 years, participated in this study. Lesions were categorized according to Neer and Hertel’s classifications, considering the preoperative prognosis for ON. After at least a year of follow-up, patients were reassessed. Data were evaluated using IBM SPSS Statistics®. Results: A total of three patients (6.8%) developed osteonecrosis. Comparisons showed no statistically significant difference, but we observed a superior association of osteonecrosis for the Hertel classification than that of Neer. Conclusion: Both classifications showed a similar ability to identify patients at low risk of developing ON. New studies with a greater number of participants and sample homogeneity may intensify the value of the evaluation of clinical applicability and predictive capacity of the studied classifications with greater significance and correlation. Level of Evidence III, Case Control Study.