Tarsal coalition is a condition that’s present at birth and happens when the bones of the hindfoot fail to separate from each other in early development so there is an abnormal connection. And, it sometimes runs in families.
Since the bones in early childhood are primarily made of cartilage, coalitions are soft early on and often go unnoticed. As the cartilage gradually turns into bone, coalitions become stiffer and are more prone to injury with activity. It’s typical that children will not have a noticeable problem until late childhood or adolescence. Tarsal coalitions can cause activity-related foot pain, stiffness or recurrent ankle sprains. Some children never have symptoms and do not require treatment.
While any bones in the hindfoot can have a coalition, the two most common types of tarsal coalition are located between the:
- Calcaneus and navicular bones
- Calcaneus and talus bones
About 50 percent of children with tarsal coalitions have them in both feet. Initial treatment is aimed at reducing symptoms. Simply decreasing sports activities for a couple weeks can sometimes help, although this is not always necessary if symptoms are mild. Over-the-counter anti-inflammatory medication (such as ibuprofen or naproxen) and icing can also reduce symptoms. If initial treatment is unsuccessful, custom shoe inserts or a trial of walking cast immobilization can sometimes help.
Surgery may be needed if other treatments fail and symptoms persist. The exact surgical procedure needed depends on the type and severity of the tarsal coalition. The expected outcomes and risks of complications from surgery vary and depend on the type of surgery needed.