B. Yu, Changhai Hospital, The Second Military Medical University, Shanghai, China
Object: To evaluate the new designed nickel–titanium (NiTi) shape memory alloy (SMA) connector for the treatment of fractures and nonunions of distal radius. Methods: The biomechanics test included photoelasticity, electrometric method and three dimensional finite element analyses. In clinical applications, 25 cases were treated by the procedure, of which 5 cases were fresh fractures of distal radius and 20 cases nonunion. The duration of postoperative follow-up was from 6 moths to 2 years (1.3 years on average). Results: The biomechanics study showed that the connector was characteristic of good anti-fatigue and reuse. The initiative memorial bone holding and longitudinal compressive forces were 98.40N~125.05N and 152N~196N correspondingly for maintaining axial stability. All the cases had primary healing without infection, angulationer and dislocation. Fracture line disappeared 9~14 weeks later postoperatively. Conclusion: The newly designed NT memory device that matches optimally the anatomy of the distal radius. It not only can maintained longitudinal compressive force continuously, but also has efficacious fixation effect with anti-shearing, bending and distracting stress. It can shorten the duration of bone healing and improve the healing quality of bone.
Summary: Abstract:A nickel–titanium (NiTi) shape memory alloy (SMA) fracure connector is described that allows management for the fractures and nonunion of distal radius. The development and finite element modelling of the shape memory alloy (SMA) fracure connector is presented in this paper. The biomechanics study showed that the connector had characteristic of good anti-fatigue and reuse. The preliminary clinical application demonstrated the use of shape memory alloy (SMA) fracure connector in the management of fractures of distal radius could reduce the duration of bone healing and improves the quality of bone healing.
Keywords: shape memory alloy (SMA), superelastic, fracture connector, distal radius
