Chondroitin Sulfate: S/DMOAD (Structure/Disease Modifying Anti-Osteoarthritis Drug) in the Treatment of Finger Joint OA Gust Verbruggen, Stefan Goemaere and Eric M. Veys Department of Rheumatology, Ghent University Hospital, Ghent, Belgium

Summary: A total of 119 patients were included in a randomized, double-blind, placebo-controlled trial in order to assess the S/DMOAD properties in OA of chondroitin sulfate (CS 4&6, 3 x 400 mg/day, Condrosulf® IBSA, Lugano, CH). Posteranterior roentgenographies of the interphalangeal (IP) joints were carried out at the start of the study and at yearly intervals. This enabled the investigators to document the radiological progression of the anatomical lesions in the pathological finger joints over a 3-year period. It was shown that the progression of OA in the IP finger joints in an individual can be determined by the evolution of his finger joints through previously described anatomical phases: ĪNā (not affected), 'S' (classical OA), ĪJā (loss of joint space), ĪEā (erosive OA) and ĪRā (remodeled joint). Structure/disease-modifying anti-OA drug (S/DMOAD) properties were searched for by assaying the number of patients developing OA in previously normal IP joints ('N' > 'S'), or progressing through the described anatomical phases of the disease ('S' > ĪJā, 'S' > ĪEā, ĪJā > ĪEā, 'S' > ĪRā, ĪJā > ĪRā, ĪEā > ĪRā). In the CS 4&6 group we observed a significant decrease in the number of patients with new 'erosive' OA finger joints. This result is particularly important since OA of the finger joints becomes a clinical problem (pain, functional loss) when 'S' joints progress to ĪJā and especially 'E' phases. During and after these ĪEā phases, joints will remodel and show the nodular deformities characteristic of Heberden's and Bouchard's nodes. Treated patients were protected against erosive evolution.

Source: Osteoarthritis and Cartilage (1998) 6, (Supplement A), 37-38 Osteoarthritis Research Society

Dr. Theo's Comments: This very well designed Belgium study proves that chondroitin sulfate can modify cartilage erosion and may prevent osteoarthritis in the finger joints. This erosion is what leads to crooked and enlarged finger joints. This type of study design provides the highest level of medical evidence.