The complex interaction between the bones, ligaments, muscles and nerves within the foot determine its anatomy. Everything that disrupts these structures can cause flatfoot.
A foot examination begins with a general examination of the whole body because flatfoot could have a hidden cause. Some of the more frequent causes of flatfoot are cerebral palsy, various forms of muscle dystrophy, early onset arthritis, genetic disorders which affect the nervous system, innate connective tissue issues.
Flatfoot may be caused by an irregular anatomy such as a tarsal coalition (abnormal connection between bones), damage to the ligaments or muscles, limited ankle movement, outwardly rotated lower legs or inward tilted knees.
Excessive weight may also lead to collapse of the foot arches due to the increased load. If the knees begin to tilt inwards, the foot arches may turn outwards. The foot will begin pointing outwards when walking, instead of straight, which may cause fatigue.