It reports on a study which looks how flat feet in an adult occur:
Adult-acquired flat foot is most common in women over 40 and often goes undiagnosed. The condition results from the gradual 'stretching out' over time of a tendon near the ankle bone -- the tibialis posterior tendon -- which is the main stabiliser of the foot arch.
The researchers looked at the very structure of this tendon:
Working with surgeons and scientists at Addenbrooke's Hospital, Cambridge and the University of Bristol, the team showed that the structure and composition of tendon specimens had changed and found evidence of increased activity of some proteolytic enzymes. These enzymes can break down the constituents of the tibialis posterior tendon and weaken it -- causing the foot arch to fall.
The study itself is available here.
What I found interesting though was the way the report skims over something important - the environmental factors......like footwear. It mentions high heels as a risk, but I wonder if shoes in general also have an impact. We dive into research into the structure of tendons that collapse. Perhaps we just need more people barefoot or in simpler shoes.