The Use of Semiquantitative Histology for Reporting Periprosthetic Tissue Features: A Review

Abstract

A semiquantitative histology grading system is recommended in the ASTM International standard for the practice of implant retrieval studies. Histological descriptions of periprosthetic tissues abound in the orthopedic literature, with a plethora of terms applied to the interpretation of adverse tissue reactions (e.g., adverse local tissue reaction, adverse reaction to metal debris, and aseptic lymphocytic vasculitis associated lesions) and particularly related to metal wear or corrosion products. The degree to which semiquantitative histological rating tools are used in these evaluations of periprosthetic tissues or how they help distinguish types of adverse reactions is unclear. A review of the orthopedic hip arthroplasty literature was performed to survey the features of scoring systems as applied to periprosthetic tissue reactions around hip replacements. A secondary question was the inclusion of immunohistological techniques in orthopedic tissue characterization. The aim of this study was to identify ways to improve the reporting of features and examine the possibility of adding new recommendations for standardized methods and terminology to ASTM retrieval standards. PubMed, EmBase, and Google Scholar were searched using: [relating to “hip prosthesis”] AND [relating to “adverse local tissue reaction”] AND [relating to “immunohistochemistry”]. Inclusion of relevant articles was determined by a two-investigator appraisal for use of a semiquantitative histology scoring, key terms within the title/abstract, English language, and not a case report/review. Two hundred and ninety nine articles were identified and 34 articles satisfied the inclusion criteria. There were eight identified scoring systems. Most ranked macrophages and lymphocytes, four graded the extent of metal particles in tissues, four included a grading for the degree of necrosis, and two evaluated the synovial lining and tissue organization. Immunohistochemistry was used in eleven articles for cell identification. None of the studies gave clear definitions of the cellular components or gradings that were considered to represent an absence of observed adverse effects, but in the future it may be useful to do so.