Final answer:
Large talar beak and C-shaped sclerosis at the subtalar joint indicate a tarsal coalition, a congenital condition where tarsal bones are abnormally connected, leading to restricted foot movements and potential discomfort.
Step-by-step explanation:
Large talar beak and C-shaped sclerosis at the subtalar joint are indirect signs of a tarsal coalition. Tarsal coalition is a condition where two or more of the tarsal bones of the foot are abnormally connected. This congenital anomaly usually manifests during late childhood or adolescence.
The subtalar joint, which allows for inversion and eversion movements of the foot, can be affected by these coalitions, resulting in limited movement and potential pain. Typical radiographic signs, such as a large talar beak and C-shaped sclerosis, suggest a limitation in the normal range of motion due to bony, cartilaginous, or fibrous bridges between the tarsal bones. Management of tarsal coalition might vary from conservative treatments like orthotics and physical therapy to surgical intervention in severe cases.