Apoptosis in the traumatic and degenerative tears of human meniscus

The apoptotic bodies were observed aging in osteoarthritic cartilage and meniscus but there is still a lack of knowledge in the literature about the relationship between meniscal injury and apoptosis. The aim of this study is to investigate the apoptotic changes on meniscal tears caused by degeneration and trauma. Thirty-eight specimens of human meniscal tissues harvested from cadavers and patients were selected from groups below the age of 40. There were 14 normal meniscal tissues from cadavers in the control group. There were 24 meniscal tissues harvested from patients who had had arthroscopic operations for meniscal tear due to degeneration or trauma. The torn meniscal samples were divided into two groups according to their etiologies, either degenerative or traumatic. Apoptotic cells were investigated in each of the three groups in the histopathological examination. There was statistically significant difference among the groups according to apoptotic index (p < 0.01). The mean indexes of apoptosis in both groups of torn meniscus (group 2 = 0.497 and group 3 = 0.725) were significantly higher than that in the normal tissue (group 1 = 0.237) (p < 0.01) but the difference between groups 2 and 3 was not significant (p > 0.001). This study indicates that an increase in the amount of apoptosis appeared to have a close relationship with meniscal tear caused by either trauma or degenerative changes.