Ficat and arlet classifi steinberg classification for hip osteonecrosis.

Table 1: Ficat and arlet classifi steinberg classification for hip osteonecrosis.

Classification and staging systems for osteonecrosis
Ficat and Arlet
Stage I	Normal
Stage II	Sclerotic or cystic lesions
	A) No crescent sign B) Subchondral collapse (crescent sign) without flattening of the femoral head
Stage III	Flattening of femoral head
Stage IV	Osteoarthritis with decreased joint space with articular collapse