Implant allergy

Area of Science:

• Orthopedic surgery
• Allergy and immunology
• Biomaterials science

Background:

• Osteosynthesis and artificial joint replacements are standard clinical procedures.
• Implant complications are typically mechanical or infectious, but material intolerance is a concern.
• Allergic reactions to implant materials like nickel, chromium, cobalt, acrylates, and gentamicin can cause symptoms such as eczema, delayed healing, effusion, pain, and loosening.

Purpose of the Study:

• To review the clinical presentation, diagnosis, and management of implant allergies.
• To highlight the rarity of implant allergies compared to cutaneous metal allergies.
• To provide recommendations for material selection in metal-allergic patients undergoing orthopedic procedures.

Main Methods:

• Review of clinical manifestations and diagnostic approaches for implant allergy.
• Discussion of differential diagnoses, emphasizing infection exclusion.
• Integration of allergological diagnostics (patch testing) and histopathology of peri-implant tissue.
• Analysis of risk factors for sensitization and allergic reactions.

Main Results:

• Implant allergies are rare despite a high incidence of cutaneous metal allergy.
• Diagnosis relies on excluding infection and employing patch testing and histopathology.
• Manifestations include eczema, delayed healing, effusion, pain, and implant loosening.
• Risk factors for sensitization and allergic reactions remain largely unknown.

Conclusions:

• Titanium-based osteosynthesis materials are recommended for metal-allergic patients.
• Metal-metal couplings in arthroplasty are generally not advised for patients with metal allergies.
• Informed consent is crucial if a cobalt-chromium-polyethylene articulation is considered for allergic patients.