Table 2.

Grading for morphology

		Morphology Change Under Optical Microscope	Grade
Ⅰ	Annulus Fibrosus (AF)	Normal texture and free of damage and distortion	1
		The damaged and distortion area is less than 30%	2
		The damaged and distortion area is more than 30%	3
Ⅱ	Boundary between AF and NP	Normal	1
		Micro disrupted	2
		Medium or severe disrupted	3
Ⅲ	NP Cells	Normal cells with large amounts of vacuoles	1
		Cells and vacuoles decreased slightly	2
		Cells decreased moderately or severely without vacuoles	3
Ⅳ	NP Matrix	Normal gel appearance	1
		Slightly congealed	2
		Moderate or severe condensation	3