The primary objective is to compare the mechanical failure risks in the first year after treatment.

Biomechanical tests have shown that augmentation of screws or nails with polymethylmethacrylate (PMMA) leads to increased mechanical properties of the bone-implant complex, leading to the assumption that augmentation could reduce mechanical failures in patients. While a few clinical studies have already been performed with augmented trochanteric nails in proximal femur fractures, no clinical studies exist with the use of Proximal Humerus Internal Locking System (PHILOS) and (PMMA) augmentation for the treatment of fractures in the proximal humerus.

In this study a new standardized technique for augmentation of screw tips using high viscous PMMA cement (Traumacem V+) with the PHILOS plate will be applied. Fracture treatment with PHILOS Screw Augmentation will be compared with treatment with PHILOS without augmentation.

Inclusion Criteria:

• Age ≥ 65 years
• Low energy trauma (e.g. fall from standing height)
• Radiologically confirmed closed fracture (≤ 10 days) of the proximal humerus
• Any displaced or unstable 3- or 4-part fracture of the proximal humerus (i.e. segment dis-placement > 0.5 cm or angulated > 45°) except isolated displaced fractures of the greater or lesser tuberosity
• Primary fracture treatment with a PHILOS plate
• Ability to understand the content of the patient information / informed consent form
• Willingness and ability to participate in the clinical investigation including imaging and fol-low-up procedures
• Signed informed consent

Preoperative Exclusion Criteria:

• Bilateral or previous proximal humerus fractures on either side
• Splitting fracture of the humeral head or humeral head impression fracture
• Cuff-arthropathy of the contra- or ipsilateral proximal humerus
• Associated nerve or vessel injury
• Any known clotting disorders, severe cardiac and/or pulmonary insufficiency
• Known hypersensitivity or allergy to any of the components of Traumacem V+ Cement Kit
• Any severe systemic disease: class 4 - 6 of the American Society of Anesthesiologists (ASA) physical status classification
• Any not medically managed severe systemic disease: class 3 of the ASA physical status classification
• Recent history of substance abuse (i.e. recreational drugs, alcohol) that would preclude reliable assessment
• Prisoner
• Participation in any other medical device or medicinal product study within the previous month that could influence the results of the present study

Intraoperative Exclusion Criteria:

• Intraoperative decision to use implants other than PHILOS/PHILOS Screw Augmentation