Table 1.

Age-related differences in selected trabecular bone properties from µCT analysis and finite element analysis of the L5 Vertebra (Mean ± SD).

Property	Unit	n=11 6 months	n=11 12 months	n=11 24 months	p-value
					6 vs. 12	6 vs. 24	12 vs. 24
Tb.BV/TV	%	39.3 ± 1.8	36.7 ± 2.3	30.0 ± 5.8	NS	<0.0001	0.0003
(Tb+Ct).BV/TV	%	19.6 ± 1.5	20.3 ± 2.1	18.6 ± 2.2	ANOVA p=0.3651
Tb.N	1/mm	3.86 ± 0.25	3.62 ± 0.16	3.17 ± 0.31	0.0332	<0.0001	0.0003
Tb.Th	mm	0.104 ± 0.006	0.102 ± 0.004	0.092 ± 0.020	NS	0.0347	NS
Tb.Sp	mm	0.230 ± 0.016	0.255 ± 0.014	0.311 ± 0.037	0.0267	<0.0001	<0.0001
Conn.D	1/mm3	60.6 ± 13.2	50.6 ± 3.7	48.4 ± 8.3	NS	0.0278	NS
Tb.TMD	mgHA/c m3	961 ± 22	981 ± 13	987 ± 19	0.0291	0.0057	NS
Trab. strengtha	N	119 ± 26	93 ± 32	78 ± 32	NS	0.0092	NS
Trab. strengthb	N	85 ± 20	67 ± 26	54 ± 25	NS	0.0148	NS
Trab. strengthc	N	150 ± 34	139 ± 28	113 ± 43	NS	0.0432	NS
(Tb+CT).BV/Ld	mm2	4.12 ± 0.28	4.27 ± 0.41	4.01 ± 0.46	ANOVA p=0.3108
Ct.TMD of shelle	mgHA/c m3	1058 ± 13	1090 ± 9	1099 ± 6	<0.0001	<0.0001	0.0409
Ct.Ar of shell	mm2	3.93 ± 0.26	4.18 ± 0.43	3.80 ± 0.63	ANOVA p=0.1625
Ct.Th of shell	mm	0.20 ± 0.01	0.20 ± 0.01	0.21 ± 0.03	ANOVA p=0.0953

^aPredicted strength of trabecular bone (excluding cortical shell of VB) using homogenous modulus 18 GPa, V_f = 2%, Failure strain = 10000 µstrain;

^busing inhomogeneous modulus, V_f = 2%, Failure strain = 10000 µstrain;

^cusing inhomogeneous modulus, V_f = 20%, Failure strain = 10000 µstrain;

^dTotal bone volume of VB divide axial length of the vertebral body was used to estimate the cross-sectional area;

^eCortical bone region surrounding the vertebral body