BIOMECHANICAL EVALUATION OF FIBERWIRE AS A TENSION BAND IN OLECRANON FRACTURE FIXATION

Introduction: Tension band wiring is a common technique for olecranon fracture fixation. The most commonly used material for the tension band is stainless steel wire. There are however problems associated with stainless steel wire. Ethibond (Ethicon Ltd, Edinburgh) has previously been cited as a suitable alternative material but not FiberWire. The biomechanical properties of FiberWire (Arthrex Ltd, Sheffield) as a tension band material have not been evaluated. This study aimed to investigate the properties of FiberWire and compare them with stainless steel wire and Ethibond. Methods: Saw-bone olecranons were osteotomised identically to create an olecranon fracture. Identical tension band constructs were produced using stainless steel wire, Ethibond and FiberWire. The construct was tested by cyclical loading with an ESH dynamic testing machine (Brierley Hill, West Mids). A preload of 5N was applied before cyclical loading at levels up to 200N. The fracture gap was measured with a displacement transducer (Tokyo Sokki Kenkyujo Co, Japan). Results: At loading up to 100N, the stainless steel wire allowed an average fracture gap of 200 micrometers. 5 gauge Ethibond allowed a larger fracture gap of 350 micrometers (p Discussion: The fracture gap with suture material was greater than with stainless steel wire, but still less then 0.5mm with loading of 100N. Free body diagram calculations determine that in a 70 kg man, this would correspond to the forces expected in extending the elbow against gravity. This means that these alternative materials are mechanically suitable for use in clinical practice for tension bands. This can avoid some of the complications of stainless steel wire. Conclusion: 5 gauge Ethibond and 2 gauge FiberWire are biomechanically suitable as alternatives to stainless steel wire in tension band wire fixation of olecranon fractures.