Comparison of lower limb calibration methods for movement analysis with inertial measurement unit (IMU)

Figures & data

Table 1. Segment axes (medio-lateral, antero-posterior, longitudinal) deduced from the different S2S calibration methods.

	Segment	Pelvis	Femur	Tibia	Foot
Posture, Movement Calibration	Upright posture	L	L	L	L
	Static with device	ML L
	Squats	ML	ML	ML	ML
	Leg Flex.^⋄	ML	ML	ML	ML
	Hip Flex.*	ML	ML
	Leg Rot.		L
	Hip Abd.	AP	AP
	Knee Flex.*		ML	ML
	Knee Rot.			L
	Knee Abd. ^●			AP

^⋄Passive movement, Leg Flex. consists in passive movements that provoke hip, knee, and ankle flexion.

* Movements done actively and in a second time passively.

^● Passive movement of the tibia in frontal plane, subject sitting.

Figure 1. Significant error in segment axes definition, P means Passive movement, *p < .05, **p < .01.