The Effect of Ding’s Screw and Tension Band Wiring for Treatment of Olecranon Fractures：A Finite Element Study

Abstract

Background:Tension band wiring (TBW) is common surgical intervention for olecranon fractures. However, high rate of complications such as loss of reduction, skin irritation, and migration of the K-wires were reported up to 80%. We have developed a new cannulated screw with holes on the tail, which called Ding’s screw. The goal of this study was to evaluate the stability of Ding’s screw and tension band wiring (DSTBW) for treatment of olecranon fractures by using a finite element analysis. Method: We conducted a finite element model by using two fixation methods: Ding’s screw and tension band wiring (DSTBW) and K-wire tension band wiring (TBW), were simulated to fix the olecranon fractures. The stress distribution, opening angle, twisting angle, and pullout strength of K-wires or screws were analyzed and compared. Results: The highest von Mises stress of fixation happened in 90°elbow movement in both groups. The value was 241.2 MPa at scews in DSTBW, and was 405.0 MPa at K-wires in TBW. Opening angle: 0.730°,0.741° at 45° and 0.679°, 0.693° at 90° elbow flexion for TBW and DSTBW, respectively. Twisting angle: 0.146°,0.180° at 45° flexion and 0.111°, 0.134° at 90° flexion for TBW and DSTBW, respectively. There was much higher pullout strength of DSTBW when compared to TBW. The maximum pullout strength was 2179.1N for screws in DSTBW, and it was 263.6N for K-wires in TBW. Conclusion: The technique of DSTBW can provide stable fixation to olecranon fractures, and reduce the risk of failure and migration of medical apparatus and instruments.