leg length

Perthes

Femur

Multiplanar deformity

- worsend by previous surgery

- may require osteotomy

Acetabulum

Dysplasia often present

- not as severe as in DDH

LLD

Can be significant

Abductors

Have been short for long time

- difficult to restore length

Reproduce the normal anatomical centre of rotation

Restore femoral offset

Maintain equal leg lengths

Usually template off normal hip

1. LLD

2. Offset

3. Femoral component

4. Acetabular component

5. Osteotomy / femoral seating