The major findings of the study were:

• More than half of all orthopaedic implants may be detected by metal detectors.
• Ninety percent of total knee replacements and all total hip replacements were detected, whether they were unilateral or bilateral. * Plates, screws, intramedullary nails and wires are rarely detected.
• Cobalt-chromium and titanium implants are much more likely to be detected than stainless-steel implants.
• Lower-extremity implants are detected 10 times more often than upper-extremity and 11 times more than spine implants.
• Upper-extremity prostheses, such as total shoulder replacements, total wrist replacements and radial head replacements, were not detected.

The abstract of the study can be viewed at:

http://www.ejbjs.org/cgi/content/abstract/89/4/742