Table 3.

Classification of acetabular chondral defects identified at arthroscopy.¹²

Severity
1	Wave Sign – detachment from sub-chondral bone Intact chondrolabral junction
2	Chondrolabral junction separation but no delamination; Cleavage tear
3	Delamination – macroscopic debonding of cartilage from acetabular bone
4	Exposed bone
Extent – Grades 1, 3 and 4 further classified into A, B and C This takes in to account of the distance of the lesion from the rim of the cotyloid fossa
A	Lesion less than one-third of the distance from the acetabular rim to the cotyloid fossa
B	One-third to two-thirds of the distance from the acetabular rim to the cotyloid fossa
C	Greater than two-thirds of the distance from the acetabular rim to the cotyloid fossa