Table 1 Comparison of MRI cartilage thickness measurements at subdivision of femoral condyle in AS patients and controls

(a) Medial compartment

R ant (mm)

1.66 ± 0.56 (0.70–2.70)

3.47 ± 0.61 (2.90–4.60)

0.0001*

R middle (mm)

1.63 ± 0.70 (0.50–3.0)

3.08 ± 0.65 (2.10–4.00)

0.0001*

R post (mm)

1.68 ± 0.38 (0.90–2.70)

3.81 ± 0.67 (2.80–4.90)

0.0001*

L ant (mm)

1.60 ± 0.64 (0.40–2.70)

3.25 ± 0.55 (2.70–4.50)

0.0001*

L middle (mm)

1.56 ± 0.57 (0.80–2.70)

2.95 ± 0.60 (2.0–3.90)

0.002*

L post (mm)

2.08 ± 0.61 (1.20–3.20)

3.61 ± 0.61 (2.60–4.70)

0.0001*

(b) Lateral compartment

R ant (mm)

1.56 ± 0.77 (0.40–3.10)

3.19 ± 1.18 (2.40–5.10)

0.0001*

R middle (mm)

1.79 ± 0.71 (0.80–3.50)

2.75 ± 0.97 (1.60–4.80)

0.003*

R post (mm)

1.90 ± 0.67 (0.70–3.50)

3.49 ± 0.85 (2.60–5.40)

0.0001*

L ant (mm)

1.54 ± 0.79 (0.40–3.10)

3.05 ± 1.08 (2.30–5.0)

0.0001*

L middle (mm)

1.78 ± 0.73 (0.60–3.50)

2.81 ± 0.90 (1.50–4.80)

0.001*

L post (mm)

1.96 ± 0.73 (0.70–3.50)

3.29 ± 0.75 (2.40–5.20)

0.0001*