The symptomatic adult flatfoot: Is there a relationship between severity and degree of pre-existing arthritis in the foot and ankle?

•No association between severity of planovalgus deformity and pre-existing severity of osteoarthritis in the ankle, subtalar, or midtarsal joints.•Increasing age is associated with severity of ankle, subtalar and midtarsal joint osteoarthritis.•No association with age and severity of planovalgus deformity.