A tarsal coalition is a union between two or more of the tarsal bones in the foot. The bridge may be osseous, cartilaginous or fibrous, and can affect various bones.

The prevalence is estimated to be approximately 1-2% and the condition is bilateral in approximately 50%. Pes planus (flat foot) is a frequent feature.

There are several types of tarsal coalition:

• calcaneonavicular
• talonavicular
• talocalcaneal
• calcaneocuboid

In this case, all of the above mentioned are present.