Background of the study:

Various studies show that the outcome of unstable distal ulna fractures after open reduction and internal fixation is better than closed reduction. The previous plate system for the distal ulna fractures is applied exclusively on the extensor side. This often leads to irritation of the extensor tendons, as well as problems with pronation and supination. With the new shape of the angle-stable distal ulna plate, the investigator hopes that the stability of the fracture osteosynthesis will remain the same and that it will be better tolerated with regard to the surrounding soft tissue, especially the extensor tendons. In this way, an otherwise practically unavoidable removal of osteosynthesis material could - at least in some cases - be avoided and some patients spared a follow-up operation.

With this in mind, the investigator tries to achieve the greatest possible reconstruction and stability for early functional follow-up treatment with a slightly bulky implant placed in the tendon-free area.

With this study, the application and usability of the new angle-stable plate system should be determined and documented.

New value of the study:

This system enables an optimal position of the plate on the distal ulna, on the one hand due to the position on the flexor side and on the other hand due to the new shape, adapted to the anatomy of the distal ulna. The locking system using angle-stable screws corresponds to the systems previously used by I.T.S.

Design:

Prospectively, handling, advantages and possible complications of the angle-stable, distal ulna plate; Company I.T.S. in the osteosynthesis of the unstable distal ulna fracture. A total of 20 patients with unstable distal ulna fractures are to be treated and evaluated over a period of 12 months according to the study design.

Risk/Benefit:

With the use of the angle-stable distal ulna plate, company I.T.S. the patients broken bone may heal better. However, it is also possible that the patient will not benefit directly from his/her participation in this clinical trial. The Expected Benefit of the Locking Distal Ulnar Plate; Company I.T.S. includes:

• Reduced risk of bone misalignment after surgery.
• Less risk of irritating tendons on the plate with the new location.
• A removal of the osteosynthesis material could possibly be avoided.

Inclusion Criteria:

1. Age over 18 years
2. unstable distal ulna fractures

Fracture classification according to Biyani [4]: all types

Exclusion Criteria:

1. Age under 18 years old
2. stable fractures of the ulna
3. Patient had one before ulna fracture
4. Patient may result in physical or intellectual disability consent not grant
5. Patient is for more Check-ups not available (Abroad)
6. Patient does not have full legal capacity
7. Alcohol and drug abuse
8. Increased risk of anesthesia (from ASA 3)

Patients with unstable distal ulna fractures who are over 18 years of age are included in this study. Patients should not have any additional pathology or previous damage to the distal radioulnar joint and should remain available for further examinations (e.g. no tourists, etc.).