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Fractures of the olecranon account for 7% of fractures in adult patients. Of all elbow fractures, 38% are isolated fractures of the olecranon. Falling on the 90 degrees flexed elbow is the most common cause of isolated olecranon fractures. Reconstitution of the joint surface is the main treatment goal, as well as stability of the joint and full range of motion and muscular strength. This can only be achieved in most cases by open reduction and precision osteosynthesis. Tension band wiring and plate osteosynthesis are the most commonly used techniques. Operative therapy is the therapy of choice, since it permits early physical therapy. Some non-dislocated fractures and fractures in elderly and multimorbid patients are indications for conservative therapy.

Background: The objective of this study was to determine the in vitro characteristics of the clinically used and newly developed implants for the stabilization of proximal humeral fractures under static and cyclic loading. The goal was to optimize implant stiffness for fracture stabilization even in weak bone stock., Methods: In a laboratory study using 35 fresh human humeri, the specimens were randomized into 5 groups, which included the clinically used humerus T-plate (HTP), the cross-screw osteosynthesis (CSO), the unreamed proximal humerus nail with spiral blade (UHN), the recently developed Synclaw Proximal Humerus Nail (Synclaw PHN) and the angle-stable Locking Compression Plate Proximal Humerus (LCP-PH). The implant stiffness was determined for three clinically relevant load cases: axial compression, torsion and varus bending. In addition, a cyclic varus-bending test was performed to determine the implant properties under cyclic loading., Results: In contrast to a rather elastic and minimally invasive implant(LCP-PH), the conventionally designed ones (Synclaw PHN, CSO, HTP, UHN) showed rather high stiffness values under static loading. In cyclic loading, a strong decrease in stiffness ( p<0.05) was found for the rigid implants HTP and UHN. In comparison with the other implants, only the elastic implant (LCP-PH) showed a significantly lower load reduction in a weak bone stock (17+/-6.2%)., Conclusion: The high initial stiffness of rigid implants led to an early loosening and failure of the implant-bone interface under cyclic loading. Implants with low stiffness and elastic characteristics, however, appear to minimize the peak stresses at the bone-implant interface, making them particularly suitable for fracture fixation in osteoporotic bone.

Irrespective of an anterior open or endoscopic approach, the combined postero-anterior instrumentation of thoracolumbar fractures requires time consuming intraoperative maneuvers changing the patients position from prone to lateral.A standardised anterior endoscopically assisted approach for the segments Th4 to L4 is described, allowing the patient to remain in prone position, using a 4-5cm incision combined with a retractor system. The approach to the anterior spine in prone position is feasible by using a self holding retractor system for the region from Th4 to L4. Time of anaesthesia for the one stage combined procedure can be reduced by about 40 min, when changing the position of the patient is no longer necessary. The minimal incision in combination with the retractor system allows mainly the use of conventional instruments and implants, which provides reasonable lower costs. The advantages of the open and the endoscopical technique are combined. The main advantage of the prone position is the opportunity to access the anterior and posterior spine simultaneously, which is extremely helpful in reduction maneuvers.