This study prospectively analyses and describes a cohort of non-elderly hip fracture patients at four orthopaedic departments in two Scandinavian countries regarding epidemiology, treatment, Patient Reported Outcome Measures, functional outcome as well as clinical results.

Hip fracture is common and well studied in the elderly population, but quite rare in the non-elderly and scarcely investigated in the literature. This prospective observational study focuses on individuals between 18 and 59 years old who have incurred a hip fracture and been treated at any of the participating orthopaedic departments in Sweden or Denmark. The study group is analysed and described at the time of the fracture and are followed during two years.

The patients' treatment follows the departments' standard rationale, there is no intervention in the study. Patients are included, after being informed and consent to participate is given, at the ward when they are admitted at the time of the fracture. The study comprises written enquiries (Patient Reported Outcome Measures, PROM) regarding hip- and global health before the fracture as well as interview and medical files and x-ray information regarding previous illness and use of medication, information about the injury, fracture type and treatment. Blood samples are used to investigate possible comorbidities and evaluate the hormonal and nutritional status and dual energy x-ray absorptiometry (DXA) is analysed with regards to reduced bone mineral density (osteopenia/-porosis). For patients with a femoral neck fracture who are treated with osteosynthesis, MRI with metal reduction is performed post-operatively and at 4 and 12 months to assess fracture healing and avascular necrosis of the femoral head.

Patients are followed up at 6 weeks by written PROM-enquiries by mail, and at 4, 12 and 24 months post-operatively with x-ray and visits in the outpatient clinic.

Inclusion Criteria:

• Acute non-pathologic hip fracture regardless of trauma energy level or previous medical conditions.

Exclusion Criteria:

• Fracture older than four weeks.
• Not able to follow up, e.g. not living in the department area.

Among hip fracture patients treated at the participating departments, patients aged 18 to 59 years, who sustain an acute non-pathological hip fracture and are treated within four weeks, are invited to participate in the study. All patients are invited, regardless of medical, cognitive and functional pre-fracture status. The participating orthopaedic departments are part of local hospitals, treating all patients in the catchment area who seeks medical care at low (Sweden) or no cost (Denmark).