Contrast medium imbibition in osteoarthritic cartilage

Abstract

Double contrast arthrography is routinely used in the examination of synovial joints as the articular cartilage and capsular surfaces are more clearly delineated than with a single contrast technique. Tears, pitting and thinning of articular and meniscal cartilages are readily identified (Stoker, 1980; Fujikawa, 1981). Stoker (1980) has described the way that osteoarthritic changes in articular cartilage are heralded by the absorption of the contrast agent. This observation forms the basis of a current investigation into the articular changes in patients with osteoarthritis of the knee using high definition microfocal radiography (Buckland-Wright, 1989; Buckland-Wright & Bradshaw, 1989). To understand the process of contrast medium imbibition into articular cartilage, the present in vitro study was undertaken to determine whether the rate and the volume of contrast medium diffusing into articular cartilage was related to the histological condition of the tissue. Thirty-seven samples of visually intact articular cartilage were obtained from the tibial plateau of fresh post-mortem subjects, three women and two men with early osteoarthritis and a mean age of 67.2 ± 15.0 years. Only five subjects were obtained for this study as we were not examining inter-subject variation but variation between samples, which were taken from different areas of the central articular regions of the medial and lateral tibial surfaces. The cartilage samples were cut to 3 × 10 mm in area, supported on approximately 10 mm of subchondral bone.