METALLOSIS AFTER TOTAL KNEE ARTHROPLASTY. THE REPORT OF 4 CASES.

Abstract

Metallosis after a total joint arthroplasty, although uncommon, is a serious complication that may occur. The deposition of metallic wear debris in the joint space may lead to thickening of the synovium and the formation of a thin dark colored film substance. We present 4 cases of metallosis from a total number of 246 total knee arthroplasties that were performed the last 10 years in our department. All patients were females with a mean age of 71.5 years (range 67 to77 years). The main symptoms were pain, swelling, and limited range of motion around the knee joint space. No signs of sinuses or wound drainage were noted. Bone scanning showed increased activity around the prosthesis. Needle joint aspiration and intra-operative wound culture were negative for any microorganism growth. Patients have had 4 types of different implants; AGC, S+G, Kirschner and Rotaglide. Extensive synovectomy and revision of all the implants were done on 3 patients and only the revision of the polyethylene component was done on one patient.

We conclude that metallosis is a serious complication that requires surgical treatment. Different diagnostic tests should be also included in order to exclude the possibility of infection. Proper alignment of the implants combined with proper soft tissue balance are 2 important factors to be respected when performing TKA.