Few subjects in orthopedics have had varied and diverse opinions expressed about every aspect of the condition, from etiology to treatment, as has the flexible flatfoot (FFF). FFF is common in infants and children, and the majority of them resolve by the 1st decade of life. Thus, FFF has been described as physiologic because it is usually flexible and painless and has been thought to be of no functional consequence. However, there is a mounting body of literature that persistent flat feet may not be as benign in terms of long-term function as was once thought to be. Despite being one of the most common concern scenarios encountered in the pediatric orthopedic outpatient department, there is an absence of a standard definition for pediatric flatfoot and a lack of clarity on the natural history of untreated persistent FFF. Looking at the precariousness surrounding flatfoot literature, we need to reevaluate if we can be confident of pain-free adulthood in untreated children with persistently severe flat feet. Excessive hindfoot motion in this entity can have far-reaching effects on the musculoskeletal chain distally and proximally. With this article, we will look deeper into the biomechanics of FFF, summarize our understanding of the literature on this entity with regard to evolution, and identify “red flag signs” in persistent FFF where intervention might be beneficial.
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