Which movement is associated with the posterior tibialis?

• A. Plantarflexion
• B. Inversion
• C. Eversion
• D. Dorsiflexion

Answer: (B)

Inversion is the movement most closely linked to the posterior tibialis. This muscle lies in the deep posterior compartment of the leg and its tendon travels behind the medial malleolus to the navicular and other tarsal bones. That path allows it to turn the sole inward, elevating and supporting the medial arch as it inverts the foot. While the posterior tibialis also assists with plantarflexion, inversion is the characteristic action that defines its role in foot movement. In contrast, plantarflexion is mainly performed by the calf muscles (gastrocnemius and soleus), dorsiflexion is driven by the tibialis anterior, and eversion is accomplished by the fibularis (peroneus) muscles.