AF Quadrant Scoring System NP Scoring System 0 Normal Disc: Concentric lamellated AF structure maintained without disruption or discolouration. No distortion between AF/NP transition zone.  0 Normal NP: No discoloration or haemorrhage. Gelatinous hydrated appearance. 1 Minor Disruption: Minor disruption/discolouration of lamella in outer half of AF zone. Preservation of inner half of AF zone and AF/NP transition zone. 1 Minor Disruption: Discoloration and/or haemorrhage < 50% NP region. No fissuring. Some evidence of nuclear dehydration. 2 Moderate Disruption: Moderate disruption /discolouration of outer half of AF extending into inner half. Preservation of AF/NP transition zone. 2 Major Disruption: Discoloration and haemorrhage > 50% NP region, and/or presence of fissuring. Dehydrated appearance.  3 Major Disruption: Disruption/discoloration of entire AF with loss of AF/NP transition zone.     4 Complete Disruption: Complete loss of lamellated structure and AF/NP transition zone with extension into NP. Bulging or prolapse of degenerate disc tissue.

Table 1: Disc morphology criteria used to score each NP and AF quadrants shown in Figure 1.