Table 1.

Data on patients and surgical procedures

Parameter	Patient
	WP1	WP2	WP4	WP5
Gender (M/F)	M	M	M	M
Age at the time of surgery (years)	62	71	63	66
Height (cm)	168	169	170	180
Body mass (kg)	66	74	60	63
Fractured vertebra	L1	L1	L1	L3
Level of internal fixation device	T12-L2	T12-L2	T12-L2	L2-L4
Bone material added	Yes	Yes	Yes	Yes
Implantation date (month/year)	09/2006	11/2006	01/2008	07/2008