The Role of Osteoporosis in Digital Templating Accuracy for Primary Cementless Total Hip Arthroplasty: A Prospective Study

Background: Total hip arthroplasty (THA) is one of the most effective treatments for end-stage hip joint disease. Two-dimensional (2D) templating represents the most widely used method for preoperative planning in clinical practice. Patient characteristics and comorbidities may further influence and complicate radiographic templating. The present study aimed to evaluate the role of comorbidities in influencing the accuracy of 2D digital preoperative planning in primary cementless THA. Methods: In this prospective observational study, all patients underwent standardized anteroposterior pelvic radiographs, and a digital templating was performed using digital software. Patient demographic characteristics, such as age, sex, BMI, and comorbidities, were extracted and all the patients were divided into matched and mismatched group for the femoral stem, femoral head, and acetabular cup. Results: The final sample consisted of 71 patients with 44 (62%) female and 27 (38%) male patients, averaging 69.8 ± 10.6 years at surgery. For the femoral stem, no statistically significant differences were found between the two groups according to comorbidities. For the femoral head, 12.5% and 50% of the patients had osteoporosis in the matched group and mismatched group, respectively (p-value = 0.002). For the acetabular cup, 18.4% and 40.9% of the patients had osteoporosis in the matched and mismatched groups, respectively (p-value = 0.043). Conclusions: Two-dimensional digital templating is a reliable technique for preoperative planning in primary cementless THA. Osteoporosis significantly influences templating accuracy, often resulting in component oversizing.