| Popis: |
Background: A tension band wiring technique is the current gold standard for osteosynthesis of olecranon osteotomies, although the technique has several practical disadvantages and its theoretical advantages have been questioned. The Step-Cut Olecranon osteotomy is an interesting new option for surgeons to access distal intra-articular humerus fractures, but its stability has only been assessed using the tension band wiring osteosynthesis. Therefore, the mean load to failure of this osteotomy with two different osteosynthesis techniques (tension band wiring and compression screws) was assessed. A higher load to failure was hypnotized for the tension-band-wiring osteosynthesis group. Methods: A Step-Cut Olecranon osteotomy was performed on 32 Sawbones. Half were secured by a tension band wiring and the other half by two compression screws. The humero-ulnar joint was simulated using an established test setup, which allows the application of triceps traction force through a tendon model to the ulna model, while the joint is in a fixed position. Eight models of each group were tested at one of two angles (20° and 70° of flexion) by isometrical loading until failure. A failure was defined as either complete fracture or gap formation of more than 2mm between osteotomy and the remaining model. Results: At 20° of flexion, the mean load to failure in the tension band wiring group was 1360 N (SD 238) and 1401 N (SD 261) in the compression screw group. At 70° of flexion, it was 1398 N (SD 215) and 1614 N (SD 427), respectively. Differences did not reach significance (p = 0.88 at 20°, p = 0.28 at 70°).Conclusions: A tension band wiring osteosynthesis does not provide higher stability than a compression screw osteosynthesis for the Step-Cut Olecranon osteotomy. A Step-Cut Olecranon osteotomy with screw osteosynthesis might be an interesting option for surgeons when treating intra-articular distal humeral fractures. |
