Histological Analysis of Early Osteolysis in Total Ankle Arthroplasty

Abstract

Category: Ankle Arthritis Introduction/Purpose: The purpose of this study was to perform a histological comparative analysis of tibiotalar joint samples taken from areas of osteolysis adjacent to total ankle arthroplasties vs control synovial specimens to determine the reaction to and presence of polyethylene (PE) particles. Methods: A total of 57 pathology samples were identified in the osteolysis group, while 11 were identified in the control group. For each sample, hematoxylin and eosin, Oil Red O (ORO), and macrophage marker CD163-stained slides were created. Polarized light and ORO stain were used to identify PE particles. The presence of metal particles and giant cell reaction to PE particles were also scored. Results: Macrophages, PE particles, metallosis, and foreign body giant cell reaction scores were significantly higher in the osteolysis group compared with the control group. In the osteolysis group, ORO staining was positive in 93% (53/57), birefringent material was present in 96.5% (55/57), and macrophage infiltrates were present in 96.5% (55/57). Foreign body giant cell reaction with giant cells surrounding PE particles was present in 49.1% (28/57) of osteolytic specimens. The presence of foreign body giant cell reaction was associated with significantly higher macrophage, ORO, and polarizable material scores. The average time to surgery for osteolysis from the index ankle replacement was 6.0 (range, 0-15) years for the 57 patients in the osteolysis group. Conclusion: This study is the largest ankle arthroplasty histological analysis to show that areas of osteolysis consist of abundant polyethylene wear particles, present both intracellularly and extracellularly. Furthermore, these areas were associated with a CD163+ macrophage infiltrate and frequently a foreign body reaction with giant cells engulfing PE particles. It is likely that implant wear particles play a significant role in osteolysis based on the histopathology.

Wear Characteristics of Conventional Ultrahigh-Molecular-Weight Polyethylene Versus Highly Cross-Linked Polyethylene in Total Ankle Arthroplasty

“…Polyethylene (PE) wear particles have been linked to osteolysis after total ankle arthroplasty. 6,19 Currently, there is no consensus on the importance of highly cross-linked polyethylene (HXLPE) in total ankle arthroplasty with regard to implant wear, or the effect of different sterilization methods on wear resistance. HXLPE components have significantly improved wear rates compared to conventional ultrahigh-molecular-weight polyethylene (CPE) components in total hip arthroplasty.…”

Medium-term results of the HINTEGRA total ankle arthroplasty

“…The criteria for a loose talar component are: subsidence greater than 5 mm or a change in position of more than 5° relative to the hindfoot axis (3,13,21) . Other studies have suggested possible implant loosening when components moved more than 5° or 5 mm in serial X-ray imaging (27)(28)33) . In our series, we had 6 cases of aseptic loosening that required conversion to fusion.…”

“…The ideal candidate for TAA is a mobile, middle-aged, or older patient with no significant comorbidities, good bone stock, and a stable and well-aligned arthritic ankle (14)(15)(16)(17)(25)(26)(27)(28)(29) . Total hip arthroplasty has a good outcome in patients younger than 30 years old, and total knee arthroplasty indications have been extended for patients younger than 55 years old.…”

“…Early failure of TAA is commonly due to infection or surgical errors, whereas late failure is due to aseptic loosening (13,27,28) . In a study done by Braito et al, 15% of TAA failures were found to be due to aseptic loosening; researchers concluded that this was the most common cause of TAA failure (37) .…”

“…Schmalzried et al observed that ORO staining had a similar sensitivity to polarized microscopy but was less specific for identifying PE particles; they recommended that the ORO staining should not be used as an isolated method for identifying PE particles. However, Schipper et al reported that this staining technique was very specific (96.4%) and sensitive (100%) (8,(27)(28) . Van Wijngaarden et al also detected PE particles in all their samples using the ORO staining method (10) .…”