Internal Femoral Torsion

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 

 

W sitting

 

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