Table 1 Semi-quantitative ultrasound scoring system

Joint Effusions

Defined as a compressible anechoic intra-capsular area

0- no effusion

1- minimal amount of effusion

2- moderate amount of effusion without distension of the capsule

3- Extensive amount of effusion with distension of the joint capsule

Synovitis

Defined as a non-compressible hypoechoic intra-capsular area (synovial thickening)

0- no synovial thickening

1- minimal synovial thickening (filling the angle between adjacent bones without bulging over the line linking the tops of the bones)

2- synovial thickening bulging over the line of the tops of the peri-articular bones but without extension along the bones diaphysis

3- Synovial thickening bulging over the lines linking the tops of the peri-articular bones and with extension to at least one diaphysis

Bone erosions

Changes in the bone surface of the area adjacent to the joint

0- Regular bone surface

1- Irregularity of the bone surface without formation of a defect in the surface of the bone seen in 2 planes

2- Defect in the surface of the bone seen in 2 planes

3- Bone defect creating extensive bone destruction

Power Doppler

Display of signal flow in the synovium

0- No flow

1- Single vessel signals

2- Confluent vessel signals in less that half of the synovium

3- Vessel signals in more than half of the area