Table 1.

Demographic data regarding primary total knee replacements without patellar component, hybrid or cemented, reported to the Norwegian Arthroplasty Register 1999–2012

Hybrid TKR	Cemented TKR	p-value
Number	4,585	20,095
Men, %	34	33	0.2
Age, years	69	70
(95% CI)	68.9–69.4	69.6–69.9	0.8
Right knee, %	53	54	0.2
ASA category a, %	74	70	0.7
ASA 1	17	17
ASA 2	62	63
ASA 3	19	18
ASA 4	0.1	0.2
ASA missing	2	2
Diagnosis preoperatively, %		< 0.001
Primary osteoarthritis	90	88
Other	10	12
Died before revision, %	11	14
Previous operations of the knee, %	31	29	0.001
Osteosynthesis affecting the knee joint	2	2	0.2
Osteotomy	3	4	0.03
Synovectomi	1	2	< 0.001
Other	26	22	< 0.001
Operation time, min (SD)	79 (28)	96 (29)	< 0.001
Intact ACL preoperatively, %	83	80	0.02
Intact PCL postoperatively, %	68	49	0.003

^aASA category: American Society of Anesthesiologists physical status classification system, only reported from 2005.