A BIOCHEMICAL, HISTOLOGIC, AND IMMUNOHISTOLOGIC ANALYSIS OF MEMBRANESOBTAINED FROM FAILED CEMENTED AND CEMENTLESS TOTAL KNEE ARTHROPLASTY

Biochemical, histologic, and immunohistochemical analyses were perform ed on 34 interface membranes obtained from 33 patients during revision total knee arthroplasty. The membranes had surrounded components of c ementless (n = 11) and cemented (n = 23) knee prostheses that were ase ptically loose. None of these implant failures was caused by catastrop hic polyethylene erosion leading to metal-to-metal contact. The histol ogic findings were similar in the membranes from cemented and cementle ss knee components: small polyethylene debris within macrophages and l arge birefringent polyethylene debris within foreign-body giant cells. Metallic debris was seen in membranes from both groups, but cemented membranes had more polymethylmethacrylate particles and more hyaliniza tion. Intracytoplasmic asteroid bodies were observed in several foreig n-body giant cells in both types of membranes. No significant differen ces were found between the two groups in levels of collagenase, prosta glandin E(2) (PGE(2)), interleukin-1 (IL-1), interleukin-6 (IL-6), or tumor necrosis factor-alpha (TNF-alpha), nor in the population of infl ammatory cells stained with IL-1, IL-6, and TNF-alpha antibodies. Memb ranes that had surrounded components with radiographic evidence of dif fuse or localized periprosthetic bone loss released significantly more collagenase, IL-1, IL-6, and TNF than did membranes from components w ithout bone loss. These two groups, however, did not have significantl y different PGE(2) levels. These findings suggest that polyethylene an d metal debris may play a role in macrophage activation and the releas e of mediators of bone resorption in the membranes surrounding failed cemented and cementless total knee implants.