Table 4.

4- and 8-week post-treatment mechanical testing

Groups	Maximum torque to failure (N m)	p value	Torsional rigidity (N m/rad)	p value	Maximum shear stress (MPa)	p value	Shear modulus (MPa)	p value
Saline
4 weeks (n = 5)	728 ± 84	0.89	62,969 ± 12,195	0.77	210 ± 26.29	0.29	7,940 ± 1,158.95	0.70
8 weeks (n = 8)	647 ± 149	0.04	63,836 ± 18,828	0.89	210 ± 46	0.22	9,239 ± 2,554	0.69
Buffer + HA/TCP
4 weeks (n = 6)	754 ± 144		57,740 ± 17,801		245.64 ± 36		8,306 ± 2,153.17
8 weeks (n = 6)	828 ± 70		63,889 ± 10,177		258 ± 33		8,608 ± 1,088
Low-dose rhBMP-2 + HA/TCP
4 weeks (n = 5)	789 ± 104		65,992 ± 5,806		253 ± 46		9,030 ± 936
8 weeks (n = 6)	765 ± 105		59,259 ± 14,865		234 ± 35		7,930 ± 1,914
High-dose rhBMP-2 + HA/TCP
4 weeks (n = 6)	740 ± 174		63,948 ± 14,238		223 ± 45		8,461 ± 1,164.52
8 weeks (n = 6)	805 ± 130		65,437 ± 12,384		244 ± 52		8,517 ± 1,976

Treated femur values; one-way ANOVA comparing all four groups at 4 and 8 weeks (mean ± standard deviation)

p value in bold indicates statistical significance