Table 1 Baseline demographic data and radiographic parameters

Demographic data

 Age, year

59.95 ± 13.01

 Sex

  Male/ Female

63/ 112

 Side

  Right/ Left

86/ 89

 Affected limb

  Yes/ No

104/ 71

Radiographic parameters (observer 1)

 Hip-knee-ankle angle, °^a

4.66 ± 4.08

 Weight-bearing line ratio, % ^a

27.03 ± 18.27

 Medial proximal tibial angle, ° ^a

85.00 ± 2.43

 Lateral distal femoral angle, ° ^a

88.40 ± 2.08

 Joint-line convergence angle, ° ^a

1.46 ± 2.24

 Posterior tibial slope, ° ^a

5.52 ± 2.89

 K-L grade (FLWAP radiographs)

  0/ 1/ 2/ 3/ 4 (Measurement 1)

56/ 47/ 31/ 23/ 18

  0/ 1/ 2/ 3/ 4 (Measurement 2)

65/ 40/ 29/ 25/ 16

 K-L grade (PA radiographs)

  0/ 1/ 2/ 3/ 4 (Measurement 1)

27/ 58/ 35/ 23/ 32

  0/ 1/ 2/ 3/ 4 (Measurement 2)

37/ 51/ 32/ 22/ 33

Radiographic parameters (observer 2)

 Hip-knee-ankle angle, ° ^a

4.99 ± 4.38

 Weight-bearing line ratio, % ^a

28.51 ± 17.59

 Medial proximal tibial angle, ° ^a

85.43 ± 2.48

 Lateral distal femoral angle, ° ^a

87.90 ± 2.09

 Joint-line convergence angle, ° ^a

1.88 ± 2.25

 Posterior tibial slope, ° ^a

5.55 ± 2.85

 K-L grade (FLWAP radiographs)

  0/ 1/ 2/ 3/ 4 (Measurement 1)

39/ 60/ 33/ 29/ 14

  0/ 1/ 2/ 3/ 4 (Measurement 2)

41/ 60/ 32/ 29/ 13

 K-L grade (PA radiographs)

  0/ 1/ 2/ 3/ 4 (Measurement 1)

31/66/25/26/27

  0/ 1/ 2/ 3/ 4 (Measurement 2)

31/70/19/30/25