Table 4.
Changes on radiograph and MR image before and after treatment.
| LPFH group (n = 376 hips) | Non-LPFH group (n = 152 hips) | |||||
|---|---|---|---|---|---|---|
| Before ESWT | After ESWT∗ | P value | Before ESWT | After ESWT∗ | P value | |
| ON lesion (%)a | 23.57 ± 8.91 | 17.92 ± 8.24 | 0.091 | 37.62 ± 9.58 | 29.78 ± 9.32 | 0.087 |
| Bone marrow edemab (hips) | ||||||
| Grade 0 | 171 | 226 | 0.007 | 22 | 83 | 0.016 |
| Grade 1 | 114 | 86 | 41 | 39 | ||
| Grade 2 | 47 | 53 | 67 | 27 | ||
| Grade 3 | 39 | 11 | 13 | 3 | ||
| Grade 4 | 5 | 0 | 9 | 0 | ||
Note: ∗the last follow-up time. ON: osteonecrosis; ESWT: extracorporeal shockwave therapy.
aThe ON lesion (%) represents the percentage of the lesion over the total femoral head surface and is shown in mean ± SD (range).
bBone marrow edema was graded 0 for no bone marrow edema, 1 for perinecrotic bone marrow edema, 2 for bone marrow edema extended into femoral head, 3 for bone marrow edema extended into neck of femur, and 4 for bone marrow edema extended into intertrochanteric region [18].