Table 1.

Summary of the main characteristics of the patients in the 2 groups

	Primary arthritis (PA) group n = 407	Posttraumatic arthritis (PTA) group n = 33	p-value
Age (years) a	72 (9)	69 (11)	0.09
Gender (M:F)	132:275	18:15	0.01
BMI (kg/m2) a	29 (5)	27 (5)	0.09
Previous knee surgeries (n) a	0.36 (0.73)	1.6 (0.93)	0.003
Charnley classification
A	323	27	0.7
B	84	6	0.7
C	0	0	–
Follow-up a	11 (3)	11 (3)	0.4

^aMean (SD)