Table 2. Results of the between level comparisons (Mean±SD).

	Lumbar level	Fat infiltration
Normal group	L23–L34	−0.26±1.98
	L34–L45	−1.37±2.82*
	L45–L5S1	−2.43±3.03**
HNP group	L23–L34	−2.21±3.24**
	L34–L45	−3.55±3.35**
	L45–L5S1	−4.62±6.37**

* p<0.05, ** p<0.001, paired t-test (Unit: mm²)