Table 1

Description of the mSASSS and CT scoring methods

mSASSSCTSS
Spinal segments assessed
 Cervical spineLower border of C2 to upper border of T1Lower border of C2 to upper border of T1
 Thoracic spineNot includedLower border of T1 to upper border of T12
 Lumbar spineLower border of T12 to S1Lower border of T12 to S1
 Range of scoring system0–720–552
Sites per vertebral endplate
 Assessment atAnterior corner4 quadrants
Scoring grades
 0No abnormalitiesNo abnormalities
 1Erosion, sclerosis, squaringSyndesmophyte <50% of IDS
 2SyndesmophyteSyndesmophyte ≥50% of IDS but not bridging
 3Bridging syndesmophyteBridging syndesmophyte
Definitions of syndesmophytes
 NewScore 0, 1→2, 3Score 0→1, 2, 3
 GrowthScore 2→3Score 1→2, 3 or 2→3
  • C, cervical; CTSS, CT Syndesmophyte Score; IDS, intervertebral disc space; L, lumbar; mSASSS, modified Stoke Ankylosing Spondylitis Spine Score; S, sacral; T, thoracic.