Table 4.

Comparison of similar studies measuring long-term polyethylene wear from radiographs

Study	Mean patient age at implantation (years)	Followup (years)	Penetration rate (mm/year)	Comment
Our study	59.6	20	0.11
Isaac et al. [12]	55	8.75	0.2
Charnley and Halley [4]	63.3	9–10	0.15	Not gamma-irradiated?
Griffith et al. [7]	> 60	8.3	0.07