wider, flatter, less mobile feet

If you have patella femoral pain, the older you get, the wider (probably for increased proprioception), flatter (possibly due to loss of intrinsic strength and extensor tone) and less mobile (for stability) you feet become. 

"This study observed that in individuals with PFP, those aged 40–50 years had less foot mobility than younger adults aged 18–29 years, as evidenced by measures of midfoot height mobility and foot mobility magnitude. These differences represented a moderate effect size, and exceed the intra-rater minimal detectable change (MDC 95%) associated with these measures (midfoot height mobility 2 mm; foot mobility magnitude 3.1 mm). The differences between age groups were specific to both midfoot height mobility and foot mobility magnitude; however, there were no differences in midfoot width mobility."

Tan JM, Crossley KM, Vicenzino B, Menz HB, Munteanu SE, Collins NJ. Age-related differences in foot mobility in individuals with patellofemoral pain. Journal of Foot and Ankle Research. 2018;11:5. doi:10.1186/s13047-018-0249-2.

free full text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5815185/