Graf

Sonographic hip type

Bony roof

Ossific rim

Cartilage rim

Alpha angle

Ia

Mature

Good

Sharp

Long and narrow, extends far over femoral head

> 60

Ib

Mature

Good

Usually blunt

Short and broad, but covers femoral head

> 60

IIa

Physiological delay in ossification > 3 months (physiological immature but stable hips)

Deficient

Rounded

Covers femoral head

50 to 59

IIb

Physiological delay in ossification > 3 months (inherently stable)

Deficient

Rounded

Covers femoral head

50 to 59

IIc

On point of dislocation (unstable, requires immediate treatment)

Deficient

Rounded or flat

Covers femoral head

43 to 49

IId

On point of dislocation

Severley deficient

Rounded or flat

Compressed

43 to 49

IIIa

Dislocated (subluxation)

Poor

Flat

Displaced upwards and echo poor

< 43

IIIb

Dislocated (subluxation)

Poor

Flat

Displaced upwards and more reflective than femoral head

< 43

IV

Dislocated (complete)

Poor

Flat

Interposed

< 43