Minimum Lateral Bone Coverage Required for Securing Fixation of Cementless Acetabular Components in Hip Dysplasia

Table 1

Modified DeLee and Charnley classification system for acetabular fixation [16, 17].

Fixation grade		Description
Bone ingrowth, stable	IA	No radiolucent line
	IB	Radiolucent line in 1 zone
	IC	Radiolucent line in 2 zones
Fibrous fixation, stable	II	Complete radiolucent line < 2 mm in width
Fibrous fixation, unstable	III	Complete radiolucent line ≥ 2 mm in width,; progressive radiolucent line in zone III, or cup migration