Hartofilakidis et al reported a classification for developmental dysplasia based on the relationship of the femoral head to the acetabulum.
Description |
Term |
Type |
femoral head in true acetabulum |
dysplasia |
A |
femoral head articulates with a false acetabulum, which partially covers the true acetabulum |
low dislocation |
B |
superior and posterior migration of the femoral head, which articulates with a false acetabulum that is discontinuous with the true acetabulum |
high dislocation |
C |
Subtypes |
Features |
B1 |
overlap between true and false acetabula > 50% |
B2 |
overlap between true and false acetabula <= 50% |
C1 |
false acetabulum present |
C2 |
false acetabulum absent |
Type |
Acetabular Segmental Defect |
Acetabular Diameter and Depth |
Acetabular Anteversion |
A |
superior |
|
|
B |
superior and anterior |
small diameter |
increased |
C |
entire rim |
small diameter with inadequate depth |
excessive |
Type |
Additional AcetabularFindings |
A |
shallowness because of osteophytes |
B |
lack of posterior bone stock |
C |
abnormal bone stock superoposteriorly |
Specialty: Surgery, orthopedic