In a radiograph, which joint is indicated by the arrow?

In a radiograph, which joint is indicated by the arrow?

• A. Subtalar
• B. Talocrural
• C. Tibiofibular
• D. Midtarsal

Answer: (B)

The arrow points to the ankle mortise—the joint where the distal tibia and fibula cradle the superior surface of the talus. This is the talocrural joint, the primary hinge of the ankle that allows dorsiflexion and plantarflexion. On radiographs, you identify it at the area where the tibial plafond meets the talar dome, enclosed by the medial and lateral malleoli. The subtalar joint sits below this, between talus and calcaneus; the tibiofibular joints are higher up, between the tibia and fibula; and the midtarsal joints are in the midfoot (between talus/navicular and calcaneus/cuboid).

The arrow points to the ankle mortise—the joint where the distal tibia and fibula cradle the superior surface of the talus. This is the talocrural joint, the primary hinge of the ankle that allows dorsiflexion and plantarflexion. On radiographs, you identify it at the area where the tibial plafond meets the talar dome, enclosed by the medial and lateral malleoli. The subtalar joint sits below this, between talus and calcaneus; the tibiofibular joints are higher up, between the tibia and fibula; and the midtarsal joints are in the midfoot (between talus/navicular and calcaneus/cuboid).