Foot Arch Support Effect on Lumbo-Pelvic Kinematics and Centre of Pressure Excursion During Stand-to-Sit Transfer in Different Foot Types

Abstract

Foot misalignments are possible risk factors for injuries to the knee and lumbar spine during daily activity. This study identified the lumbo-pelvic–knee kinematics and centre-of-pressure progression characteristics of the human trunk during stand-to-sit (STSI) transfer in people with different foot types. This study investigates the lower arch foot influence on lumbar–pelvic–knee kinematics and centre-of-pressure progression trunk characteristics during STSI transfer. Thirty-nine participants were assessed using the R-scan footscan system to define three different foot types (flat feet, normal feet, and asymmetric feet). Two electro goniometers and one inclinometer were used to record lumbar, pelvic and knee joint kinematic data during STSI transfer. A Tekscan mat system laced under the gluteal area was used to measure the trunk centre-of-pressure progression. The centre-of-pressure progression path, standard path deviation, velocity and acceleration were calculated. The flat foot group tended to use a more frontal plane range of motion and velocity in the pelvis than the normal group. The asymmetric foot group exhibited smaller sagittal plane lumbar motion and velocity, with a more frontal plane motion and velocity than normal participants. When arch support was used, the centre-of-pressure path standard deviation in the medial–lateral and anterior–posterior directions exhibited a significant decrease in all groups. There were no significant differences in kinematics, total centre-of-pressure path and centre-of-pressure progression acceleration between those with and without foot arch support. Participants with flat or asymmetric feet might have difficulty distributing the load forces evenly through both lower limbs and must use a different lumbar–pelvic strategy to compensate. Whether these adaptive kinematic strategies in the low arch group induce the development of injury requires further long-term investigation.