Table 1 Characteristics of study objects.
Non perforated group | Perforated group | p-value | |
|---|---|---|---|
Number of joints | N = 168 | N = 131 | |
Age (year)*** | < 0.001 | ||
Median [IQR] | 27.0 [22.0; 33.0] | 32.0 [26.5; 44.5] | |
Gender* | 0.029 | ||
Male | 30 (17.9%) | 10 (8.4%) | |
Female | 138 (82.1%) | 120 (91.6%) | |
Shape of the disc*** | < 0.001 | ||
Biconcave | 30 (17.9%) | 1 (0.8%) | |
Folded | 46 (27.4%) | 7 (5.3%) | |
Flattened | 34 (20.2%) | 17 (13.0%) | |
Eyeglass-shaped | 40 (23.8%) | 35 (26.7%) | |
Amorphous | 18 (10.7%) | 71 (54.2%) | |
Signal intensity of bone marrow*** | < 0.001 | ||
Normal | 152 (90.5%) | 87 (66.4%) | |
Low | 16 (9.5%) | 44 (33.6%) | |
Fluid collection | 0.178 | ||
Grade 0 | 82 (48.8%) | 54 (41.2%) | |
Grade 1 | 58 (34.5%) | 52 (39.7%) | |
Grade 2 | 24 (14.3%) | 18 (13.7%) | |
Grade 3 | 4 (2.4%) | 7 (5.3%) | |
Disc displacement*** | < 0.001 | ||
Normal + ADcR | 51 (30.4%) | 7 (5.3%) | |
Early ADsR | 56 (33.3%) | 31 (23.7%) | |
Late ADsR | 61 (36.3%) | 93 (71.0%) | |
Joint space*** | < 0.001 | ||
Normal | 38 (22.6%) | 7 (5.3%) | |
Narrowing | 125 (74.4%) | 91 (69.5%) | |
Bone to bone contact (close) | 3 (1.8%) | 12 (9.2%) | |
Bone to bone contact (open) | 2 (1.2%) | 21 (16.0%) | |
Changes of condyle and fossa*** | < 0.001 | ||
2 or less features | 149 (88.7%) | 72 (55.4%) | |
2 or more features | 19 (11.3%) | 58 (44.6%) |
