- Most common sensitizers are: nickel, cobalt, and chromium
- Incidence of sensitivity: Chromium=0.2%, nickel=1.3%, and cobalt=1.8% (Swiontkowski MF, J Orthop Trauma 2001; 15: 86-89).
- Stainless steel and cobalt-chromium alloys contain the above sensitizers, especially Nickel.
- Titanium and titanium alloys generally do not contain the above sensitizers.
- People with a history of allergies to cobalt, chromium or nickel generally are not sensitive to titanium or its common alloys. (Ti-6AL-4V)
- Metal allergy may affect 10-15% of the population (Hallab N, JBJS 2001;83A:428). Prevalence may be increasing (Thyssen JP, Contact Dermatitis 2007;57:287).
- Patients with a potential metal sensitivity should be seen by a dermatologist or allergist for testing prior to any orthopedic implant. (Mesinkovska AN, MD, Arch Dermatol. Published online February 20, 2012)
- Dermatologist generally use testing kits such as, T.R.U.E Test Patch Test for testing. (www.truetest.com or www.allerderm.com, 800-365-6868)
- Patients with metal sensitivity or a nickel allergy may report nonspecific deep generalized pain over the implant.
Metal Allergy TKA
- Patients with metal allergy should be treated with a modular titanium or all poly tibial component and an oxidized zirconium femoral component. Titanium has a propensity for metallosis and is not suitable for the articulating portions of the components. (Laskin RS, CORR 2003;416:191).
Metal Allergy THA
- Press-fit titanium stem, ceramic (alumina) head, and cementless titanium cup.
- Titanium femoral heads are susceptibility to abrasive wear. Cemeted titanium stems transmit greater stresses to the cement column and are not recommended. Titanium is less stiff than cobalt-chrome (and stainless steel).
- Hallab N, JBJS 2001;83A:428
- Thyssen JP, Contact Dermatitis 2007;57:287