Plate Fixation Versus Intramedullary Nailing of 3 and 4 Part Proximal Humerus Fractures

Inclusion Criteria: 1. Patients \> 18 years 2. Severe displacement, defined as malposition of at least 45⁰ of angular deviation in valgus or 30⁰ in varus in true frontal projection, regardless of whether the fracture is impacted or not. Fractures with more than 50% displacement of the head against the surgical neck 3. The greater or lesser tubercles must be fractured in a 3 or 4-part fracture. The degree of displacement is not critical for inclusion. Exclusion Criteria: Exclusion criteria: 1. Fracture more than 3 weeks' old 2. Caput humeri just a thin shell or split 3. Ipsilateral damage that will influence the recovery and scoring systems 4. Incapability to protect osteosynthesis, i.e. use of crutches because of injury to lower extremity. 5. Pathological fracture 6. Neurovascular injury 7. Open fracture 8. Noncompliance 9. Congenital anomaly 10. Ongoing infectious process around the incision site for plate osteosynthesis 11. Systemic disease that may influence healing processes or scoring systems (RA/MS) 12. Fracture dislocation 13. Substance abuse 14. Inability to read and understand Norwegian 15. Patients not residing in our catchment area 16. Patients with too small humerus diameter to use a nail 17. Patient not able to commit and understand written consent