Table 1.

Baseline patient characteristics and SPARCC MRI SSS, and change over 2 years (exercises 1 and 2) or 1 year (exercise 3) from patients with SpA.

Patient CharacteristicsExercise 1, n = 45Exercise 2, n = 102Exercise 3, n = 40
No. readers423
Age, mean (SD)41.4 (12.6)39.9 (11.3)36 (9.4)
Males, n (%)34 (76)77 (75)34 (85)
Symptom duration, yrs, mean (SD)15.9 (10.5)16.9 (9.9)14 (8.4)
BASDAI, mean (SD)5.3 (2.5)4.7 (2.4)5.5 (2.2)
CRP, mg/l, mean (SD)13.5 (15.0)13.0 (17.0)11.5 (13.7)
Taking only NSAID, n (%)17 (38)39 (38)17 (43)
Taking TNF-α inhibitor, n (%)23 (51)56 (55)21 (53)
SSS fat score, 0–40*, mean (SD) (range)
  Baseline3.38 (4.07) (0–17)3.84 (6.54) (0–31.5)4.61 (6.30) (0–26)
  Change0.21 (1.43) (−4.25 – +5.75)0.33 (2.03) (−6 – +11)0.73 (1.80) (−4 – +6)
SSS erosion, 0–40*, mean (SD) (range)
  Baseline3.09 (3.37) (0–15)3.03 (4.01) (0–21)4.63 (2.77) (0–18)
  Change−1.32 (2.04) (−8.25 – +4.25)−0.94 (2.56) (−12 – +6)−0.63 (1.67) (−9.33 – +6)
SSS backfill, 0–20*, mean (SD) (range)
  Baseline3.68 (4.34) (0–17.8)2.76 (3.68) (0–19)4.93 (3.09) (0–18)
  Change0.5 (2.55) (−7.25 – +10.75)0.06 (2.45) (−14.5 – +8)−0.03 (1.61) (−8.33 – +7.33)
SSS ankylosis, 0–20*, mean (SD) (range)
  Baseline5.27 (7.96) (0–20)6.16 (8.02) (0–20)2.36 (3.86) (0–14.7)
  Change0.15 (1.13) (−2.25 – +6.5)0.36 (1.73) (−5 – +9)0.58 (1.39) (−1.33 – +7.67)
No. of patients SSS fat, mean, n (%)
   Baseline > 025.3 (56)44 (43)24.3 (61)
  Change > 019.8 (44)34 (33)17.3 (43)
  Change > SDC19.8 (44)25.5 (25)17.3 (43)
No. of patients SSS erosion, mean, n (%)
  Baseline > 026.8 (59)54 (53)32.3 (81)
  Change > 024 (53)52 (51)32 (80)
  Change > SDC17.3 (38)27 (26)20.3 (51)
No. of patients SSS backfill, mean, n (%)
  Baseline > 023.8 (53)43 (42)31 (78)
  Change > 024.3 (54)36 (35)27.3 (68)
  Change > SDC18.5 (41)27 (26)16.7 (42)
No. of patients SSS ankylosis, mean, n (%)
  Baseline > 016.5 (37)47 (46)13.7 (34)
  Change > 011.8 (26)27.5 (27)12.7 (32)
  Change > SDC11.8 (26)27.5 (27)7 (18)
  • * Maximum scoring range for SSS score. Baseline SSS score > 0 denotes at least 1 SIJ quadrant in the 5 coronal slices assessed in the SSS method with the structural lesion. Change SSS score > 0 denotes at least 1 SIJ quadrant of the 5 SIJ slices with a new or resolved structural lesion. SPARCC: the Spondyloarthritis Research Consortium of Canada; MRI: magnetic resonance imaging; SSS: Sacroiliac joint Structural Score; SpA: spondyloarthritis; BASDAI: Bath Ankylosing Spondylitis Disease Activity Index; CRP: C-reactive protein; NSAID: nonsteroidal antiinflammatory drug; TNF-α: tumor necrosis factor-α; SIJ: sacroiliac joint.