Definition
Transverse plane rotation of the femoral neck axis anteriorly relative to the transcondylar axis
Epidemiology
F:M = 2:1
Bilateral, symmetrical
Aetiology
Unknown
Familial
NHx
Increases up to age of 5
- resolves by age of 8
Resolves in 95%
- compensatory ETT may develop after 5 years
- little functional disability
>50% of patients with persistent femoral anteversion achieve normal gait
Doesn't predispose to OA
Presentation
Intoeing in early childhood
- starts 3 years old
- maximum 4-6 years old
Examination
Squinting patellae
Sit in W
Run like egg beaters & trip over
Prone Rotation test / Gages Trochanteric Angle
- find position where GT most prominent laterally
- angle tibia makes from vertical is FAV
Increased IR
- abnormal if IR > 70°
- if severe, no ER possible
CT scan
If surgical intervention deemed likely
DDx
If unilateral / progressive rule out DDH / CP
Non operative
No evidence for orthoses
Operative
Indications
Very severe functional gait disturbance
Cosmesis
Age > 10
Rotational criteria
- IR > 85° & ER <10°
- measured Anteversion > 50°
Principles
Leave until at least > 8-10 years old because many resolve
Not required if 10° ER present
Subtrochanteric derotation osteotomy
Proximal femoral plate
Aim IR = ER on table