Flexible pediatric flatfoot is a difficult and common etiology that has many treatment options available. Surgical treatment can be very complicated, especially in a child with potential to grow. A subtalar arthroereisis implant can provide correction without the need for osteotomies or tendon transfers, however is scarcely used. This study evaluates the amount of radiographic correction and mid-term clinical outcomes of pediatric flatfoot corrections performed with the use of a subtalar arthroereisis implant. They found satisfactory results with limitations specifically in transverse plane correction and can be a viable option in patients without a transverse plane deformity.