Normalization of chromium and cobalt values after femoral head replacement.

Introduction Adverse reaction to metal debris (ARMD) can be caused by metal-on-metal total hip arthoplasty. We treated a case of ARMD in a 61-year-old patient by limited prosthetic revision, replacing the metal head with a polyethylene one. Presentation of case Two years after metal-on-metal total arthoplasty of the left hip, radiographic control showed osteolysis of the patient’s greater trochanter. He underwent surgical curettage and the application of demineralized bone matrix. After a few months, blood Co and Cr increased, and at clinical evaluation, the patient had worsening paresthesias. He agreed to prosthetic revision after 14 months. Discussion During surgery, the acetabular cup and femoral stem appeared correctly osteointegrated; therefore, the cup was maintained, while the prosthetic femoral head was removed and replaced with a 50 mm polyethylene head. Conclusion Blood Cr and urinary Cr and Co decreased and normalized 3 months after surgery, and the patient no longer suffered paresthesias. Blood Co normalized 7 months after revision. Radiographic follow-up showed no change after 30 months post-operatively. We believe this case report could be a starting point for a future randomized clinical trial to test the efficacy of the procedure used compared with complete implant revision.