Light microscopic identification of submicron polyethylene wear debris

A simple, yet specific, means to identify submicron polyethylene (PE) particles in routine histologic sections would be practically useful. We have previously reported a very fine, diffuse, birefringence (when viewed under polarized light) in the cytoplasm of phagocytic cells from around total hip replacements (THRs) with a PE acetabular bearing and proposed that this finding was caused by multiple submocron PE particles. In order to determine the specificity of this light microscopie finding, we have analyzed a wide range of specimens (N = 27), characterized by a foreign‐body inflammatory response to both biologic and prosthetic material, that do not contain PE. In no case was there any suggestion of the diffuse cytoplasmic birefringence that is characteristic of specimens from THRs with a PE acetabular bearing surface. This study indicates that, within the range of orthopedic implant materials and designs currently in use, this diffuse birefringence is a specific finding and it represents a simple, practical, and useful method for ligh microscopic identification of submicron PE.