Is Gelsolin a Biomarker for Aseptic Loosening After Total Knee Arthroplasty?

Gelsolin (GSN) has been implicated in inflammatory reactions in asthmatic patients and may be a marker for acute or chronic reactions in synovial tissue. Detection of increased levels of GSN in synovial fluid could differentiate between aseptic loosening (low GSN) and hypersensitivity reaction (high GSN). Synovial fluid from both knees of 7 cadaver specimens with unilateral TKA was analyzed using ELISA for GSN levels. Components were explanted after spiral CT scans to determine wear patterns and loosening. Results were compared to synovial fluid from 7 consecutive TKA revisions for aseptic failure. Average GSN levels for cadaver native and well-functioning TKA knees were 24,534±10,437 ng/mL and 38,430±30,907 ng/mL, respectively (p=0.314). Average GSN level for revision patients was 53,294±19,868 ng/mL, significantly higher than cadaver well-functioning TKAs (p=0.006). The patient with the highest level of GSN at time of revision surgery showed significant metallosis at the time of surgery.