History: 35 year old male with foot pain.
This is the appearance of pes planus, or flatfoot, which occurs in up to 20% of adults with no other abnormalities.
There are many contributors to pes planus deformity, including hindfoot valgus shown by increased talocalcaneal angle to greater than 45 degrees, midfoot sag or lisfranc ligament injury, and forefoot pronation (seen as overlapping metatarsals in the images above). Pes planus can be idiopathic, due to posterior tibialis tendon injury, charcot joint, lisfranc ligament injury, rheumatoid arthritis, or tarsal coalition. It is important to always obtain weightbearing films to assess for alignment, and compare with the contralateral foot.