Clinical and Radiological Outcomes of Extracorporeal Shock Wave Therapy in Early-Stage Femoral Head Osteonecrosis

Table 4

Changes on plain radiographs and MRI images before and after ESWT.

Variable	Before ESWT	After ESWT	P-value
Size of ONFH (%)	59 ± 32 (5-76)	28 ± 16 (0-63)	0.235
Bone marrow edema
Grade 0	3	20	0.003
Grade 1	9	9
Grade 2	16	4
Grade 3	3	0
Grade 4	2	0

The values, given as the mean and standard deviation with the range in parentheses, represent the percentage of the involved area of the femoral head. ESWT: extracorporeal shockwave therapy; ONFH = osteonecrosis of the femoral head.