AB0844 THE ENIGMA OF FRAGILITY FRACTURE WITH NORMAL BONE MASS; EXPERIENCE OF A LIAISON SERVICE FRACTURE UNIT

Background The enigma of fragility fracture with normal bone mass; Experience of a Liaison Service Fracture Unit Objectives To describe the characteristics of patients with fragility fracture and normal DXA treated in an FLS unit. Methods Prospective 6-year observational study of a FLS fracture unit. Demographic variables, FRAX items, DXA and TBS were collected. The characteristics of patients with normal and abnormal DXA are described. The statistical analysis was performed by means of a descriptive, comparing the normal DXA/osteopenia/osteoporosis groups by means of contingency tables, Fisher’s exact test, Student’s t test or ANOVA, as appropriate, as well as regression analysis. Results 1,631 patients were included, 205 with normal DXA (12.5%), 747 with osteopenia (45.8%) and 680 with osteoporosis (41.6%). Patients with normal DXA were characterized by a higher percentage of males, a younger age and a higher BMI. Hip fracture was less frequent in patients with normal DXA, while the frequency of other fractures was higher. The frequency of previous fracture, history of hip fracture of the parents and secondary osteoporosis was lower in patients with normal DXA. The TBS and FRAX values were higher in the cases of normal DXA compared to osteopenia and osteoporosis. In the multiple regression analysis, excluding TBS, remained significant associated with abnormal DXA age (OR 1.04; 1.03-1.06), sex (OR 2.48; 1.71-3.58), BMI (OR 0.91; 0.89-0.94),) and parent hip fracture (OR 1.99; 1.11-3.58). Including TBS Conclusion Patients with fragility fracture and normal DXA are younger, with more frequent males and with BMI and higher TBS values. Acknowledgement Fabiola Santana y Carmen Alonso Disclosure of Interests Antonio Naranjo Grant/research support from: Amgen, Consultant for: UCB, Speakers bureau: Amgen, UCB, Soledad Ojeda Grant/research support from: AMGEN, Speakers bureau: AMGEN, Aida Saavedra: None declared, Cristina Sepulveda: None declared, Amparo Molina Speakers bureau: AMGEN, Tatiana Marrero: None declared, Maria Pino Afonso: None declared, Margarita Ramirez: None declared, Nieves Martin: None declared, Alicia Olivares: None declared, Carlos Rodriguez-Lozano: None declared