Joint Coordination to Maintain Postural Balance Differs Between Preferred and Non-preferred Lower Limbs

The maintenance of postural balance depends on coordinated actions between the joints on both sides of the body. Although biomechanical modeling studies assume symmetry between the sides of the body in the control of postural balance, it is known that lateral preference makes the lower limbs functionally asymmetric in people without neurological impairment. However, it remains inconclusive whether the coordination between joint and segmental angles to maintain balance differs between the lower limbs according to lateral preference. The study investigated the coordination of joint and segmental angles for preferred (right) and non-preferred (left) lower limb movement for static and dynamic tasks during a single-legged postural task. Eighteen healthy young adults in single-legged upright posture were evaluated. The angular variability was assessed by analyzing the first eight principal components. The cross-correlation analysis between the main components and the angles examined showed that when the support on the ground was on the non-preferred lower limb, there was greater participation of the upper segments compared to the support of the preferred limb. The preferred support of the lower limb on the ground generated angular variability among the participants in the hip, knee, and ankle joints, that is, the most distal part of the body. There is a wide range of strategies for distributing the variability of the principal components between the original angles on the left side.