Which term describes movement of the foot medially? Extension Inversion Abduction Adduction Flexion
The correct answer and explanation is:
Correct Answer: Inversion
Explanation (300 words):
The movement of the foot medially refers to a motion in which the sole of the foot turns inward, toward the midline of the body. This specific movement is called inversion.
In anatomical terms, inversion is the movement of the plantar (bottom) surface of the foot so that it faces medially (toward the opposite foot). This is most commonly seen when you “roll” your ankle inward or lift the inner edge of your foot off the ground. It mainly occurs at the subtalar joint, which lies between the talus and calcaneus bones in the foot.
To understand why inversion is the correct answer, let’s briefly consider what the other terms mean:
- Extension refers to increasing the angle between two body parts—like straightening the knee or ankle. At the ankle, extension is often called plantarflexion (pointing the toes down).
- Flexion is the opposite of extension and means decreasing the angle between two body parts. At the ankle, this is called dorsiflexion (lifting the foot upwards toward the shin).
- Abduction is the movement of a body part away from the midline. In the case of toes, it means spreading them outward.
- Adduction is the movement of a body part toward the midline. Again, in toes, this refers to bringing them together.
So, neither abduction nor adduction describes the inward turning of the sole of the foot.
Inversion, on the other hand, is the precise term used in anatomy to describe the medial movement of the sole of the foot. It is important in understanding common injuries like ankle sprains, where excessive inversion can damage the lateral ligaments of the ankle.
Therefore, the correct and most accurate answer is inversion.