The pathology of failed total joint arthroplasty.

In 94 cases of failed total hip and knee joint arthroplasties, acute and chronic inflammation, acrylic, metal, and polyethylene debris, and histiocytic reaction were assessed in a 0, 1+, 2+, 3+ semiquantitative manner. Chronic inflammation of 2+ to 3+ was not particularly useful in separating a reaction to wear debris from infection. At the time of frozen section, 2+ to 3+ acute inflammation (greater than 5 PMNs per high power field) was used with excellent follow-up bacteriologic correlation to delay replacement of the failed prosthesis until the infection was controlled. Acrylic (2+ to 3+) and excessive polyethylene wear debris correlated well with loosening. Dusky grey cells were the hallmark of metal-filled histiocytes. Mononuclear and multinuclear histiocytes (2+ to 3+) were correlated with excessive acrylic and/or polyethylene debris. The histologic features of metal particles, acrylic voids, polyethylene and teflon fibers and silastic globules illustrate the pathologic identification of these materials.