Intra-articular absorption and distribution of ketoprofen after topical plaster application and oral intake in 100 patients undergoing knee arthroscopy

Abstract

OBJECTIVE: The primary objective of this study was to assess the kinetics of ketoprofen in synovial fluid and intra-articular tissues in relation to plasma. The secondary objective was to study whether intra-articular tissues act as reservoirs. METHODS: The ketoprofen concentration was analysed in plasma, synovial fluid and intra-articular tissues after single application of a 30 mg plaster (n = 40), multiple applications for 5 days (n = 30) or oral intake of 50 mg (n = 30) in patients undergoing knee arthroscopy. RESULTS: Median CMax values after topical application were 12.8 ng/ml in synovial fluid, 56.7 ng/g in synovial tissue, 349.3 ng/g in meniscus and 568.9 ng/g in cartilage. CONCLUSION: Topical applications of ketoprofen allow the attainment of high intra-articular tissue concentrations.