Rheumatology: Current Research
Open Access

Measurement of wire deflection on loading may indicate progress to union in fine wire Ilizarov constructs: An in vitro model

5^th International Conference of Orthopedic Surgeons and Rheumatology

June 16-17, 2016 Alicante, Spain

Beth Lineham, Todd Stuart and Paul Harwood

University of Leeds, UK
Leeds General Infirmary, UK

Posters & Accepted Abstracts: Rheumatology (Sunnyvale)

Abstract :

Introduction: No entirely reliable method exists for assessing union during Ilizarov treatment. Premature removal results in treatment failure and alternative methods warrant investigation. Wire deflection might provide an indication of fracture site deformation on weight-bearing, indicating progress towards union. This study aimed to test a method for assessing wire deflection within an Ilizarov frame. Materials & Methods: Tests were performed on clinical grade, all tensioned wire, 4 ring Ilizarov constructs stabilizing a simulated bone, with and without an unstable defect. Models were sequentially loaded to 700N using an Instron testing machine. A digital depth gauge attached to the superior ring measured relative wire displacement at the ring closest to the fracture. Tests were repeated 3 times. Results: In the unstable model, wires tensioned at 882N and 1274N produced mean maximum deflections of 2.76mm and 2.69mm compared with 0.050mm and 0.046mm in the intact bone model (significant p<0.0001 Students T-test). Both models produced highly linear load deformation curves (R2=0.983 and 0.997). Conclusions: A measurable difference in wire deflection between stable and unstable situations exists using this method, which appears valid and reliable with clear correlation between displacement and load. This approach might be clinically applicable and further clinical testing is required.

Biography :

Email: bethbrown@doctors.org.uk