Table 1 Degeneration histologic grading scale

I Anulus fibrosus

Grade:

1

Normal, pattern of fibrocartilage lamellae without ruptured fibers and without a serpentine appearance anywhere within the anulus

2

Ruptured or serpentine patterned fibers in less than 30% of the anulus

3

Ruptured or serpentine patterned fibers in more than 30% of the anulus

II Border between the anulus fibrosus and nucleus pulposus

Grade:

1

Normal

2

Minimally interrupted

3

Moderate/severe interruption

III Cellularity of the nucleus pulposus

Grade:

1

Normal cellularity with large vacuoles in the gelatinous structure of the matrix

2

Slight decrease in the number of cells and fewer vacuoles

3

Moderate/severe decrease (>50%) in the number of cells and no vacuoles