Table 4.
Summary of the cartilage regeneration status
| MRI evaluation | |||
|---|---|---|---|
| BiCRI (n = 47) | Microfracture (n = 45) | P value | |
| T2-weighted fast spin-echo image (12th month) | |||
| N | 45 | 45 | |
| Not evaluated | 0 | 1 (2.2%) | 0.20 |
| Fully regenerated | 20 (44.4%) | 14 (31.1%) | |
| Partially regenerated | 24 (53.3%) | 25 (55.6%) | |
| Not regenerated | 1 (2.2%) | 5 (11.1%) | |
| Proton density image (12th month) | |||
| N | 45 | 45 | |
| Not evaluated | 0 | 0 | 0.14 |
| Fully regenerated | 20 (44.4%) | 14 (31.1%) | |
| Partially regenerated | 24 (53.3%) | 26 (57.8%) | |
| Not regenerated | 1 (2.2%) | 5 (11.1%) | |
| Arthroscopic evaluation | ||
|---|---|---|
| BiCRI (n = 26) | Microfracture (n = 22) | |
| Grade 0 | 3 | 0 |
| Grade I | 9 | 11 |
| Grade II | 12 | 7 |
| Grade III | 0 | O |
| Grade IV | 1 | 2 |
| Not evaluable | 1 | 2 |
P value: Cochran-Mantel–Haenszel test adjusted for the study site
Grade 0: normal cartilage
Grade I: cartilage with softening and swelling
Grade II: a partial-thickness defect with fibrillation or fissures on the surface that did not reach subchondral bone or exceed 1.5 cm in diameter
Grade III: fissuring to the level of the subchondral bone in an area with a diameter of more than 1.5 cm
Grade IV: exposed subchondral bone