Table 3.

Accuracy of digital image measurements under simulated limb and camera mal-positioning

Knee flexion/extension	Simulated limb (L) or camera (C) position	Difference between true knee flexion/extension and measured flexion/extension
16° knee extension	15° abduction (L)	2
16° knee extension	30° abduction (L)	1
96° knee flexion	15° abduction (L)	1
96° knee flexion	30° abduction (L)	10
16° knee extension	15° adduction (L)	1
16° knee extension	30° adduction (L)	0
96° knee flexion	15° adduction (L)	5
96° knee flexion	30° adduction (L)	10
16° knee extension	15° clockwise (C)	1
16° knee extension	30° clockwise (C)	1
16° knee extension	45° clockwise (C)	6
96° knee flexion	15° clockwise (C)	3
96° knee flexion	30° clockwise (C)	5
96° knee flexion	45° clockwise (C)	14
16° knee extension	15° anti-clockwise (C)	0
16° knee extension	30° anti- clockwise (C)	2
16° knee extension	45° anti- clockwise(C)	8
96° knee flexion	15° anti- clockwise (C)	3
96° knee flexion	30° anti- clockwise (C)	14
96° knee flexion	45° anti- clockwise (C)	28