Orientation of motion | Range of motion | Maximum difference between IK and FD | NRMSE (%) | |
---|---|---|---|---|
IK | FD | |||
Intact knee model | ||||
 Internal/external rotation | 2.7 to 12.5 (range 9.8°) | 2.1 to 11.8 (range 9.7°) | 0.8° at 30° of knee flexion | 5.4a |
 Adduction/abduction | 3.3 to 6.4 (range 3.1°) | 3.4 to 6.4 (range 3°) | 1.7° at 22° of knee flexion | 11.8a |
 Anterior/posterior translation | 1.3 to 9.3 (range 8 mm) | − 2.6 to 14 (range 16.6 mm) | 6.7 mm at 100° of knee flexion | 74.6 |
 Proximal/distal translation | 2.5 to − 20.3 (range 22.8 mm) | 4.5 to − 12.4 (range 16.9 mm) | 7.9 mm at 100° of knee flexion | 10.6a |
 Lateral/medial translation | − 0.8 to − 5.7 (range 4.9 mm) | − 2.4 to − 5.6 (range 3.2 mm) | 2.1 mm at 50° of knee flexion | 30.4 |
ACL-sectioned knee model | ||||
 Internal/external rotation | 3.9 to 13.4 (range 9.5°) | 4.9 to 13.6 (range 8.7°) | 2.5° at 50° of knee flexion | 16.5a |
 Adduction/abduction | 2.5 to 6.5 (range 4°) | 4.4 to 6.5 (range 2.1°) | 3.8° at 20° of knee flexion | 26.7a |
 Anterior/posterior translation | 1.6 to 11.1 (range 9.5 mm) | − 1.9 to 14.3 (range 16.2 mm) | 10.5 mm at 63° of knee flexion | 60.5 |
 Proximal/distal translation | − 3.2 to − 24.3 (range 21.1 mm) | − 0.5 to − 17.4 (range 16.9 mm) | 6.9 mm at 100° of knee flexion | 11.2a |
 Lateral/medial translation | − 0.9 to − 6.2 (range 5.3 mm) | − 2.3 to − 5.6 (range 3.3 mm) | 2.55 mm at 54° of knee flexion | 30.7 |