Introduction: After surgery of proximal humerus fractures complications such as failure of osteosynthesis with bad functional outcome are often observed. We predict, that the treatment with an angular stable plate will reduce the risk of secondary dislocation. Patients and Methods: Eleven patients with displaced proximal humerus fractures, treated with the proximal humeral internal locking system plate (PHILOS, Synthes), including two patients who are treated for non-union of an earlier fracture. They were monitored clinically and radiologically for a mean of 8.4 months by the same surgeon who had operated the patient. Results: Average Constant Score at six months: 70.3; average range of motion: 121° flexion, 108° abduction, 21° external rotation and internal rotation lumbar vertebra (L) L 4-L 5. We observed one case of partial avascular necrosis, one case of complex regional pain syndrome I and two cases of non-union, one with a break of the plate. There were no infections. Conclusion: This implant provides good stability in treatment of displaced humeral head fractures with good clinical and radiological results, however with a high complication rate. These results remain be compared to other kind of treatments and implants.