Biofilms and prosthetic devices

Summary

THE USE OF PROSTHETIC DEVICES IN MEDICINE

Prosthetic devices are used to repair or replace a structure or function which has been damaged or is absent as a result of disease, trauma (including surgery) or congenital defect. The limits on their use are considerations of mechanical properties or function, and biocompatibility, and these are progressively being overcome as new biomaterials are developed. However, most prosthetic devices in common use are made from a narrow range of biomaterials, such as silicone elastomer, polyurethanes, fabricated polytetrafluoroethylene (Teflon) or polyethylene terephthalates (Dacron), titanium, stainless steel, ceramics and composite materials containing carbon or glass fibres.

Most prosthetic devices are used in either children or the elderly, and the proportion of the population comprising these two age groups is increasing in most developed countries. It is likely, therefore, that the absolute numbers of prosthetic devices used each year will rise rapidly. Examples of such devices are large joint (hip, knee, shoulder, etc.) replacements for arthritis, spinal fixation to stabilize the spine after cancer or trauma, prosthetic heart valves, pacemakers, vascular grafts for obstructed or weakened major arteries, voice prostheses for those whose larynx has been removed because of cancer or trauma, central venous catheters for parenteral nutrition or anticancer drug administration, catheters for peritoneal dialysis for those with renal failure, and shunts to control hydrocephalus, or pathological accumulation of fluid in the brain.

Incidence and resource implications of device-related infection

While biodeterioration or mechanical dysfunction are important complications, the most feared is infection, which occurs at widely varying rates between devices.