Table 4.

Comparison of the Distribution of Residual Patellar Thickness

Thickness (mm)a)	Group Ab)		Group Bc)
	No. of subjects	Cumulative (%)d)	No. of subjects	Cumulative (%)d)
<12d)	23	7.5	6	2.1
12–14	88	36.9	66	23.9
14–16	115	75.3	122	64.8
16–18	52	92.5	57	83.8
18–20	16	97.9	36	95.8
20–22	6	100	9	98.6
24–26	0	100	2	99.3
26–28	0	100	0	99.3
28–30	0	100	2	100

^a)Thickness of the residual patella.

^b)Group A patients who received the Attune prosthesis.

^c)Group B patients who received the PFC Sigma prosthesis.

^d)The proportion of high-risk cases with a residual patellar thickness of less than 12 mm was significantly different between the groups (p=0.003).