Table 2.

Comparison of bone mineral density of the left femoral neck between the two groups before and after the treatment.

	N	Before treatment	6 months after treatment	12 months after treatment
ZOL	121	0.41 ± 0.05	0.45 ± 0.05	0.58 ± 0.05∗
Conservative	121	0.41 ± 0.05	0.43 ± 0.04	0.44 ± 0.05
P		0.76	<0.01	<0.01

^∗ P < 0.05 ZOL group vs conservative group 6 month after treatment.