The larger muscles that move the foot and toes are located in the leg, while smaller muscles are located in the foot. This lesson describes the major muscles responsible for the various movements of the foot at the ankle and the toes.
My daughter is a Kansas State champion gymnast. She is in fantastic shape, and she has great flexibility.
She is so cute as she stands on her toes, just before she starts her routine. As she tumbles, the muscles of her thigh control the movement of her leg, and the muscles of her leg control the movement of her foot and even her toes.
The larger muscles controlling movement of the foot and the toes are located in the leg. We refer to them as the extrinsic muscles of the foot. This allows for the foot to be less bulky and capable of fine movements with fewer restrictions. Smaller muscles located in the foot are referred to as intrinsic muscles of the foot, and they move the toes and support the arch of the foot.
This lesson will identify the major extrinsic as well as intrinsic muscles of the foot that are used to perform everyday as well as gymnastics routines.
Extrinsic Foot Flexors and Extensors
Most of the muscles that move the ankle produce what we call plantar flexion, which occurs when we run or walk. The bottom, or plantar surface of the foot, moves down and our heel is raised. This is the same movement performed while standing up on the balls of your feet.The gastrocnemius is a major plantar flexor as it originates from the distal end of the femur and inserts on the heel via the calcaneal tendon. Deep to the gastrocnemius, the soleus also produces plantar flexion, and it originates from the proximal tibia and fibula and inserts on the heel via the calcaneal tendon, much like the gastrocnemius.
Let me quickly note the calcaneal tendon is also known as the Achilles tendon, so named for Achilles, the Greek hero of the Trojan War. Legend holds that Achilles met his demise when Paris shot him with an arrow in the heel, thus slowing him down and making him vulnerable.
If we peel away the soleus, we can see the fibularis longus and the fibularis brevis that produce eversion of the foot and plantar flexion. The tibialis posterior produces inversion of the foot, as well as plantar flexion, and the plantaris is unique in that it produces not only plantar flexion of the foot, but also some flexion of the leg at the knee due to its origin on the femur.
Most of the leg muscles are posterior, while the tibialis anterior, in the anterior compartment, produces dorsiflexion of the foot at the ankle. With dosiflexion, the toes are raised and the heel is lowered. That’s just the opposite of plantar flexion.
Extrinsic Toe Flexors and Extensors
Now that we’ve identified the major foot movers, let’s take a look at some of the extrinsic muscles that move our toes. Looking at the posterior leg muscles, we see the flexor digitorum longus, as it originates from the leg and inserts on phalanges two through five. This produces flexion of these toes or digits.The flexor hallucis longus originates from the leg and inserts on the great toe, or phalange number one.
That’s your big fat toe, and this produces flexion of the great toe. In the anterior of the leg, the extensor digitorum longus and the extensor hallucis longus have the same attachments of their respective flexors, thus producing extension of the digits.
Intrinsic Foot Muscles
The intrinsic muscles of the foot originate from the tarsal and metatarsal bones and insert on the digits. While they are small in comparison, they are important for assisting with movement of the toes, as well as maintenance of the arch.
Let me identify a few of these muscles. The flexor digitorum brevis and the extensor digitorum brevis insert on digits two through five and produce flexion and extension, respectively, of these digits.
The flexor hallucis brevis and the extensor hallucis brevis insert on the great toe and produce flexion and extension of the great toe, respectively.
It makes sense that these muscles are named brevis as they are shorter; that is, brief in comparison with the like-named extrinsic muscles producing similar actions.
In summary, lots of muscles produce movement of the foot and toes. The extrinsic foot muscles are located in the leg, while the intrinsic foot muscles are located in the foot. The gastrocnemius, soleus, fibularis longus, fibularis brevis, tibialis posterior and plantaris all produce plantar flexion. The fibularis muscles produce eversion of the foot, while the tibialis posterior produces inversion.
The tibialis anterior produces dorsiflexion of the foot.The flexor digitorum longus and the extensor digitorum longus are extrinsic foot muscles that produce flexion and extension of our digits two through five. The flexor hallucis longus and the extensor hallucis longus are extrinsic foot muscles producing respective movements of the great toe, which is digit number one. Finally, the intrinsic muscles controlling these movements of the toes include: the flexor digitorum brevis, the extensor digitorum brevis, the flexor hallucis brevis, and the extensor hallucis brevis.
At the end of this lesson, you’ll be able to identify the extrinsic and intrinsic foot muscles and describe their actions and attachments.