Table 3.

Spearman’s rank correlation order of the elements measured in intervertebral disc samples

Spearman	Al	Si	Cu	Mg	Zn
Al	x
Si	0.47*	x
Cu	−0.25	−0.50*	x
Mg	0.50*	0.46*	−0.32	x
Zn	0.27	0.09	−0.08	0.75*	x

*Statistically significant; p value <0.01