After cemented THR, failures at stem-cement interface and at bone-cement interface mainly resulted from the occurrence of abonormally high cement stresses and excessive micromotions (e.g. Jasty et al., 1991, Gardiner and Hozack, 1994). High compressive stress was source of cement fracture and enhanced the stem subsidence (e.g. Phillips et al., 1990) while excessive slipping enhanced the creation of cement debris (e.g. Rothman and Cohn, 1990). Bone-cement slipping leaded to a necrosis of bone that inter-digitize with the cement while the stem-cement debonding might induced the stem loosening (e.g. Harris, 1992) and peri-prosthetic osteolysis (e.g. Burke et al., 1991). The coupling effects between the two interfaces are complex. Increasing the sem roughness influence not only the shear friction at the stem-cement interface but also promotes the bone-cement failure (e.g. Gardiner and Hozack, 1994). In parallel, evidence of the effects of cement thickness has been observed either clinically or experimentally (e.g. Ebramzadeh et al., 1994).
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