Advantages of Biodegradable
Pins Over Metal Fixation
Introduction The field of internal fixation has long been dominated by the use of metal implants, in particular those manufactured from stainless steel, cobalt chrome and, in more recent years, titanium. However, despite widespread use and availability, utilisation of metal implants in fracture repair is not without its disadvantages.
Metal implants e.g. plates, pins, wires, mesh etc. have been associated with many physical problems including:
Metal pins, for example in the form of Kirschner wires (K-wires), can be used in the repair of many types of bone defects, e.g. fractures and osteochondral/chondral lesions. These implants in particular have been linked to several other problems. The most evident of these is the need to remove the implant once its purpose has been served (Jani and Parker 2004), specifically to remove protruding wires involved in the repair of hand and foot fractures. This causes added stress and discomfort to the patient and necessitates a further expensive and time-consuming procedure.
of using metal pins include infection and pin migration, bending or
breaking. There is, therefore, an obvious need for the widespread
A new generation of biodegradable implants has been created using the Inion OPTIMATM family of materials. By blending L lactide, D lactide, TMC (Tri-Methylene Carbonate) and occasionally also Glycolide (when particularly fast degradation is required), Inion has been able to establish a ’library’ of materials from which to select those with the most appropriate strength, toughness and degradation profile to meet specific clinical requirements.