Which muscle is a primary dorsiflexor of the foot?

Which muscle is a primary dorsiflexor of the foot?

• A. Gastrocnemius
• B. Tibialis anterior
• C. Peroneus longus
• D. Flexor digitorum longus

Answer: (B)

Dorsiflexion at the ankle is carried out mainly by the tibialis anterior. This muscle sits in the front of the leg and, when it contracts, pulls the foot upward toward the shin and helps invert the foot. It’s the primary dorsiflexor, essential for clearing the foot during the swing phase of walking. The gastrocnemius is primarily a plantarflexor through the Achilles tendon and also crosses the knee, so it doesn’t dorsiflex. The peroneus longus everts the foot and assists with plantarflexion, not dorsiflexion. The flexor digitorum longus mainly flexes the toes and assists with plantarflexion, with little to do with dorsiflexion.

Dorsiflexion at the ankle is carried out mainly by the tibialis anterior. This muscle sits in the front of the leg and, when it contracts, pulls the foot upward toward the shin and helps invert the foot. It’s the primary dorsiflexor, essential for clearing the foot during the swing phase of walking. The gastrocnemius is primarily a plantarflexor through the Achilles tendon and also crosses the knee, so it doesn’t dorsiflex. The peroneus longus everts the foot and assists with plantarflexion, not dorsiflexion. The flexor digitorum longus mainly flexes the toes and assists with plantarflexion, with little to do with dorsiflexion.