A LARGE Austrian nationwide analysis has revealed that osteoporosis often goes unrecorded in hospital records after a fragility fracture, with hip fractures far more likely than wrist or arm fractures to be linked to a formal osteoporosis diagnosis, particularly in men. Comorbidity network analysis characterised sex- and age-specific diagnoses co-occurring with osteoporosis, coded as with (M80) or without (M81) pathological fracture. Hip fractures showed the strongest co-occurrence with osteoporosis, particularly in females aged 60 and older, whereas upper limb fractures showed no osteoporosis diagnoses among significant co-diagnoses in any age group, despite being considered early fragility fractures. Implications for Fragility Fracture Recognition in Clinical PracticeThese findings have suggested that osteoporosis is not systematically coded across all fracture types in routine hospital data, with upper limb fractures rarely recorded alongside osteoporosis diagnoses despite being recognised as potential fragility fractures. Sex-and age-specific comorbidity networks associated with osteoporosis and fragility fractures in nationwide data.