Search

Aim: Medial meniscus tear has been proposed as a potential etiology of spontaneous osteonecrosis of the knee (SONK). Disruption of collagen fibers within the meniscus causes meniscal extrusion, which results in alteration in load distribution in the knee. Our purpose was to determine whether the extent of medial meniscus extrusion correlates with the severity of SONK in the medial femoral condyle. Methods: Radiological stage of SONK and femorotibial angle (FTA) were determined on knee radiographs. Ellipsoid volume of SONK lesion and meniscal pathology (degeneration, tear and extrusion) were evaluated by magnetic resonance imaging. Results: All the 18 knees with SONK in the present study showed substantial extrusion (≥ 3 mm) and degeneration of the medial meniscus. The extent of meniscal extrusion and FTA were strongly associated with the stage and volume of the SONK lesion. Multiple linear regression analysis revealed that medial meniscus extrusion and FTA were useful predictors of the volume of the SONK lesion. Conclusion: There was high association of medial meniscus extrusion and FTA with the radiological stage and volume of the SONK lesion. Increased loading in the medial femoral condyle with greater extrusion of medial meniscus and varus alignment may contribute to expansion and secondary osteoarthritic changes of a SONK lesion. [ABSTRACT FROM AUTHOR]

Previously, we have adapted a recently developed three-dimensional chemosensitivity test, the collagen gel droplet embedded culture drug sensitivity test (CD-DST), for evaluation of chemosensitivity of 12 anticancer drugs against colorectal adenocarcinoma, and surprisingly, it was found that tumor growth enhancement was occasionally observed even after exposure to anticancer drugs. In this study, the CD-DST was applied for human cervical carcinoma cell line HeLa-Ohio (HeLa) cells and its MDR1/P-glycoprotein-overexpressing subline, Hvr100-6 cells, and 12 anticancer drugs were assessed in terms of chemosensitivity and deterioration of tumor, and the results were compared with those by two-dimensional WST-1 assay. Growth enhancement was observed in Hvr100-6 cells, not in HeLa cells, for mitomycin C with the ratio of total volume of colonies in the treated group to that in the untreated group (T/C%) of 135.0%, doxorubicin with T/C% of 162.5% and cyclophosphamide with T/C% of 122.0%, and this was not observed in WST-1 assay. Multidrug resistance was detected both for CD-DST and WST-1 assay. The values of T/C% in CD-DST were comparable with or higher than those of the survival fraction (%) in WST-1 assay, and modification of WST-1 assay procedure gave similar results, suggesting a higher resistance in three-dimensional than in two-dimensional culture. Further investigations should be addressed to the association of MDR1/P-glycoprotein with tumor growth enhancement.