One of the most commonly utilised materials today for surgical uses is stainless steel.
It is biocompatible, easy to clean and sterilise, strong, and resistant to corrosion. These characteristics make stainless steel ideal for surgical instruments such as hypodermic needles and catheters. Specialty stainless steels are also used for surgical implants such as bone fixation screws and prosthetic joints.
While there are over 60 grades of stainless steel, stainless steels are essentially iron alloys bearing at least 10.5% chromium and less than 1.2% carbon by weight. The specialty grades of stainless steel that are most commonly used in surgical implants also contain molybdenum (about 3%) and nickel (about 14%).
In recent years, a specialist alloy called Nitinol has emerged as another nickel-containing material for biomedical applications. Comprised of nickel and titanium, Nitinol is commonly used in stents – small hollow tubes used to keep arteries open, and in kink-resistant guidewires for placing implants.
Amongst the millions of surgical implant operations carried out each year in short and long-term applications, an isolated number of occasions have been reported where the presence of nickel in the implant alloy is suspected of causing an allergic reaction. This advisory note aims to provide reassurance and advice about the safe use of nickel as part of an alloy in surgical applications.