Authors (including presenting author) :
WANG H(1)
Affiliation :
(1) Prosthetic & Orthotic, Pamela Youde Nethersole Eastern Hospital
Introduction :
The flexible flatfoot is a common disorder with 20% occurrence among adults, caused by the collapsed medial arch with the lower extremity ligamentous laxity. The collapsed and pronated feet will alter the lower limb alignment, including tibia and femur internal rotation and anterior pelvic tilting. Some flatfoot may suffer back, hip, knee, and foot pain due to the malalignment, requiring foot orthosis to alleviate the pain and deformities. However, the current research mainly focuses on the correction outcomes on the feet and knee. Except for the feet and knee, the effects on the anteriorly tilted pelvis, whose malalignment would impact the pelvic muscle activities, sensory-motor control, and induce the degenerative joint disease.
Objectives :
For finding the effect of the foot orthosis on correcting the anterior pelvic tilting by the foot orthosis, this project studied the outcomes of different arch support height in restoring the pelvic position.
Methodology :
This project is separated into two parts. The first objective is to study the normal range of pelvic tilting of normal and flatfoot persons. The second is to learn the effect of foot orthosis on correcting the pelvic alignment. In stage 1, this project had recruited 20 normal adults and 11 subjects with flexible flatfoot. Stage 2 included ten flatfoot subjects with anterior pelvic tilting in stage 1.
Result & Outcome :
It was found that most of the flatfoot subjects have more significant anterior pelvic tilting compared to the normal subjects in stage 1, regardless of whether the subjects have hip flexor contracture. Under the walking condition, the flatfoot subjects tend to tilt the pelvis posteriorly. After the experiment of stage 2, it was found that the anterior pelvic tilting is reduced with the arch support, and the corrective results become significant with the increase of the arch support height both under standing and walking. However, as the subjects may feel discomfort when wearing the arch support with excessive height, the arch support height design should be tolerable for daily use. Through the analysis, it was also found that the correction outcomes depend on the individual difference. However, the relationship between the individual differences and the orthotic outcomes is complicated, which needs the further research.
