A NEW EXTERNAL FIXATION SYSTEM FOR TIBIAL FRACTURES

Abstract

In a novel external fixation system for tibial fractures accurate reduction is achieved with a complex temporary device (Staffordshire Orthopaedic Reduction Machine: STORM) following which the reduced fracture is fixed using a simple titanium bar fixator (IOS). With the fracture reduced, the external fixator screws may be placed in the optimum position. The fixator is designed to allow controlled bending to optimise movement at the fracture site for callus growth. With no need for adjustable elements, the fixator is small and short enough for epicentric placement in the commonest fracture of the middle and distal thirds. Optimum mechanical properties are approached: elastic return is to the reduced position; epicentric placement minimises shear and distraction on weightbearing. Integral healing assessment measures bending stiffness. The device is single-use.

In 40 tibial fractures (closed or grade I compound) the mean healing time was 15 weeks with a healing endpoint of bending stiffness of 15Nm/deg in two orthogonal axes and full weightbearing on fixator removal with no subsequent creep or refracture. Good reduction, defined as less than 5 deg of maximum angulation and less than 3mm of maximum translation, was achieved and maintained. The incidence of pin site complications was extremely low and there were no deep infections.

This new device thus far has had few of the drawbacks commonly associated with external fixation. The infection rate is low, healing time is comparable to other methods and there have been no malunions. We feel our strict adherence to fracture reduction and pin site hygiene are the most important factors in producing these excellent results.