Table 3.

Life table for the posterolateral approach group

Year (x)	Number at risk in year x	Number of revisions in year x	Probability of revision in year x	Cumulative proportion surviving	95% confidence interval
0	774	0	0	1.000	1–1
1	709	3	0.004	0.996	0.991–1
2	686	1	0.001	0.994	0.989–1
3	630	3	0.005	0.990	0.982–0.0997
4	526	1	0.002	0.988	0.979–0.996
5	407	0	0	0.988	0.978–0.996
6	273	0	0	0.988	0.976–0.996
7	153	2	0.013	0.980	0.958–0.994
8	91	1	0.011	0.972	0.939–0.993
9	24	0	0	0.972	0.909–0.993