To improve the reliability of the quantitative scorings of the synovial biopsies, we evaluate whether diameter of arthroscopic forceps influences histological quality of synovial tissue and/or histological scores and we compare the intra- and inter-observer performances of the main histological scoring systems. Synovial biopsies were retrieved in the same part of the joint using 1, 2 and 4 mm diameters grasping forceps. After standard staining and immunohistochemistry with anti-CD68 antibody, slides were scored blindly by 2 independent experienced operators for tissue quality and with Krenn score, de Bois-Tak score and CD68 semi-quantitative score. Four samples did not pass quality control. No difference other than a higher number of vessels in the 4 mm versus 2 mm forceps (p = 0.01) was found among the 3 groups. CD68 score was significantly higher in the 2 versus 4 mm forceps (p = 0.009). So we concluded that only vessels quantification and CD68 semi-quantitative score seemed affected by the forceps size. The intra-reader agreement was variable across observers and features: 0.78 (0.66-0.87) for the Krenn scoring system, 0.89 (0.78-0.97) for the de Bois-Tak score and 0.93 (0.81-1.00) for the CD68 score. Interobserver reliabilities of Krenn score, de Bois-Tak score and CD68 scores were satisfactory: 0.95 (0.92-0.99) for Krenn, 0.98 (0.96-0.99) for de Bois-Tak and 0.80 (0.71-0.89) for CD68.