Zone III corresponds to which anatomical structure?

Zone III corresponds to which anatomical structure?

• A. Proximal gastrocnemius
• B. Mid-gastrocnemius
• C. Distal Achilles tendon
• D. Calcaneus

Answer: (C)

Zone III is the distal portion of the Achilles tendon, the segment that runs toward the heel just before the tendon inserts into the calcaneus. This labeling places the proximal gastrocnemius in the more proximal parts of the muscle-tendon unit and the mid-gastrocnemius in the middle portion, while the calcaneus is the bone at the end of the tendon. Knowing this helps you localize pathology within the tendon itself, separate from the muscle belly or the bone insertion.

Zone III is the distal portion of the Achilles tendon, the segment that runs toward the heel just before the tendon inserts into the calcaneus. This labeling places the proximal gastrocnemius in the more proximal parts of the muscle-tendon unit and the mid-gastrocnemius in the middle portion, while the calcaneus is the bone at the end of the tendon. Knowing this helps you localize pathology within the tendon itself, separate from the muscle belly or the bone insertion.