Titanium is a very popular metal, used not only in medicine but also made familiar by its use in shipbuilding, aircraft and vehicles, to name just a few applications. The reasons mentioned for the use of titanium implants in trauma surgery, including on the spine, are primarily biocompatibility and corrosion resistance. An important advantage is also that magnetic resonance imaging studies are possible with absolute safety, which is for example of considerable relevance for intracranial aneurysm clips in neurosurgery.
The view, however, in which titanium implants in fracture fixation have better biocompatibility and reduced infection rates predominantly on the basis of less potential corrosion, arise from in-vitro and in-vivo studies, “but not from clinical evidence,” said Dr. Sebastian Weckbach from the University Hospital of Ulm. He says that titanium implants could even have several disadvantages, such as an increased risk
- of early implant failure and
- of complications arising from revision surgery or removal of the material. Moreover, costs are higher.
Indirect comparison of clinical results
Therefore together with his colleagues Weckbach investigated in a retrospective study whether using titanium implants in fracture treatment actually benefits the patient more than plates and screws made of steel alloys. The central question of the recently published study (“the trauma surgeon“) was whether titanium implants are associated with higher complication and revision rates in the restoration of peripheral fractures. For the study, the team evaluated data from a trauma center in the United States (Denver Health Medical Center). Included were all patients over 15 years of age treated between 1 January 2006 and December 31 2010 who were, due to a limb fracture, fitted with steel plates in osteosynthesis. The results were compared by Weckbach and his colleagues with the data published until that time on complications associated with titanium implants for identical indications and fracture sites. Data from 751 patients, whose 774 fractures were fitted with 859 steel plates, was evaluated.
Better results with steel plates
According to the trauma surgeons, the complication rate in these patients amounted to 8.01 percent (n=62), the surgical revision rate being 5.16 percent (n=40). As expected, the complication and revision rates were higher for open fractures: In comparison to the rates in closed fractures (7.4 and 4.3 percent) they were 16.4 and 13.5 percent. Overall, the results were, according to Weckbach and his colleagues, even better than the published results for titanium plates used for identical indications.
Steel implants: safe and economically viable
The conclusion of Weckbach and his colleagues is: Given the “multiple negative aspects associated with the material properties of titanium, and the lack of evidence for improved outcomes with use of titanium implants in trauma surgery, it appears that the anecdotal and widespread assumption of the inferiority of steel in comparison to titanium implants is not understandable and is scientifically unfounded”. Steel implants for fixing fractures would therefore be a “safe and economically viable alternative to the widespread use of titanium implants as is taking place in central Europe”. The frequently cited argument of increased allergy risk with implants made of steel alloys, particularly those with nickel, does not convince Weckbach. For one thing, there are now nickel-free steel implants.
And secondly, there have also been accounts from titanium implants of cross allergies to nickel and cobalt intolerance, which led to complications. In any case, as opposed to frequently occurring cutaneous metal allergies, implant allergies appear to be rare; major survey data is however lacking it says in a statement of opinions already assembled in 2008 by the interdisciplinary body Implant Allergy Working Group made up of members from several professional societies. In any case, not every patient in whom there has been an aseptic loosening of the implant should be hastily classified as “allergic” emphasises orthopedist Dr. Heiko Meyer from the University Hospital of Magdeburg.