Table 4.

Clinical and imaging differences between osteonecrosis femoral head and subchondral insufficiency fracture

	SIF	ONFH
Age/sex	Elderly/female	30 s to 40 s
Etiology	Osteoporosis/obese	Steroid/alcohol
Bilateral	Rare	50%-70%
Shape of the band	Iregular, disconnected	Smooth
High signal of the proximal	Yes	No
Segment on gadolimium MRI

From Yamamoto T. In: Yamamoto T. Subchondral Insufficiency Fractures of the Femoral Head. Clinics in Orthropedic Surgery 2012: 4: 3. SIF: Subchondral insufficiency fracture; ONFH: Osteonecrosis femoral head; MRI: Magnetic resonance imaging.