Understanding Your Foot: A Tendon Overview
When you’re dealing with foot or ankle pain, understanding the anatomy of your foot is key to figuring out what’s going on and how to treat it effectively. And when you’re talking about foot and ankle problems, tendons are a big part of the picture. Knowing where they are and what they do is essential for understanding how your foot works and how injuries happen.
Think of your foot as having three main sections: the hindfoot (heel), the midfoot (arch), and the forefoot (toes). All three work together to give you stability, cushion the impact of walking, and help you push off when you move.
This article gives you a detailed look at the tendons in your foot, including a foot tendons diagram, where they’re located, what they do, and why they’re important when it comes to foot health. Let’s take a closer look at what makes your foot tick!
Regions and Columns of the Foot
The foot is typically divided into three regions: the hindfoot, the midfoot, and the forefoot. It can also be described as having two columns: the medial column and the lateral column.
Hindfoot
The hindfoot includes the talus and calcaneus (heel bone). The talus has a pretty poor blood supply, which can slow down healing if it’s injured.
The hindfoot is the first part of your foot to contact the ground when you take a step, and it’s responsible for absorbing a lot of the impact.
Midfoot
The midfoot is made up of the navicular, cuboid, and cuneiform bones.
It helps to stabilize your foot and move weight and momentum from the hindfoot to the forefoot as you walk or run.
Forefoot
The forefoot includes the metatarsals and phalanges (toe bones).
The forefoot helps with balance and pushing off the ground.
Columns of the Foot
The medial column consists of the calcaneus, talus, navicular, cuneiforms, and first metatarsal. It’s more mobile than the lateral column, allowing your foot to adjust to uneven surfaces.
The lateral column includes the calcaneus, cuboid, and fourth and fifth metatarsals. It’s built to provide stability and support your weight.
Bones and Joints of the Foot
The foot is a complex structure made up of bones, joints, ligaments, muscles, and tendons, all working together to support the body, provide balance, and enable movement. Here’s a look at some of the major bones and joints in your feet:
Key Bones
- Talus: This important bone in the upper part of the foot has a relatively poor blood supply. About 70% of the talus is covered in hyaline cartilage.
- Calcaneus: The calcaneus is the largest bone in your foot, and it forms your heel.
- Navicular: Located on the medial (inner) side of the foot, the navicular bone connects with the talus and cuneiform bones.
- Cuboid: Situated on the lateral (outer) side of the foot, the cuboid bone articulates with the calcaneus and metatarsals.
Key Joints
- Ankle Joint (Tibiotalar): This joint allows for dorsiflexion (lifting the foot up) and plantarflexion (pointing the foot down).
- Subtalar Joint: The subtalar joint enables inversion (turning the sole of the foot inward) and eversion (turning the sole of the foot outward).
- Transverse Tarsal Joint (Talonavicular and Calcaneocuboid): This joint helps with foot flexibility and allows the foot to adapt to uneven ground.
- Metatarsophalangeal (MTP) Joints: These joints allow your toes to flex (bend downward) and extend (bend upward).
Ligaments of the Foot and Ankle
Ligaments are the strong, fibrous bands of tissue that connect bones to each other, providing stability to joints. The foot and ankle have a complex network of ligaments that allow for a wide range of motion while maintaining structural integrity. Here’s a quick tour:
Lateral Ligaments
These ligaments are on the outside of your ankle:
- Anterior Talofibular Ligament (ATFL): This is a major stabilizer of the ankle, and it’s the ligament that’s most often injured in ankle sprains, especially when you turn your foot inward.
- Calcaneofibular Ligament (CFL): This ligament also helps stabilize the ankle joint on the outside.
- Posterior Talofibular Ligament (PTFL): The strongest of the lateral ligaments, this one provides support to the back of the ankle.
Medial Ligaments (Deltoid Ligament)
- Deltoid Ligament: This isn’t just one ligament; it’s a group of them on the inside of the ankle that work together to provide strong support.
Plantar Ligaments
- Spring Ligament (Plantar Calcaneonavicular Ligament): This ligament supports the head of the talus bone and helps maintain the arch on the inner side of your foot.
Lisfranc Ligaments
- Lisfranc Ligaments: This set of ligaments stabilizes the joints between your tarsal bones (in the midfoot) and your metatarsal bones (in the forefoot).
Extrinsic Muscles and Tendons of the Foot
The muscles that move your foot and ankle are located in your lower leg. Long tendons extend from these muscles and attach to the bones in your foot. These are known as the extrinsic muscles and tendons of the foot. Here’s a look at some of the major players:
Superficial Posterior Compartment
- Gastrocnemius and Soleus: These two muscles come together to form the Achilles tendon, which is responsible for plantarflexion, the movement that lets you point your toes.
Deep Posterior Compartment
- Tibialis Posterior: This tendon supports the arch on the medial or inner side of your foot.
- Flexor Digitorum Longus: This muscle flexes your four lateral toes (all toes except the big toe).
- Flexor Hallucis Longus: This muscle flexes your big toe.
Anterior Compartment
- Tibialis Anterior: This muscle helps you flex your foot upward (dorsiflexion) and turn your foot inward (inversion).
- Extensor Hallucis Longus: This muscle extends your big toe.
- Extensor Digitorum Longus: This muscle extends your four lateral toes.
- Peroneus Tertius: This muscle assists with dorsiflexion and also helps you turn your foot outward (eversion).
Lateral Compartment
- Peroneus Longus: This muscle helps you turn your foot outward and point your toes.
- Peroneus Brevis: This muscle also helps turn your foot outward.
Intrinsic Muscles and Tendons of the Foot
The muscles and tendons in your feet give you the strength and flexibility you need to stand, walk, run, and jump. Here’s a look at the intrinsic muscles and tendons of the foot, divided by location:
Dorsal Aspect (Top of Foot)
- Extensor Digitorum Brevis: This muscle extends your second, third, and fourth toes.
- Extensor Hallucis Brevis: This muscle helps you extend your big toe.
Plantar Aspect – First Layer (Bottom of Foot)
- Abductor Hallucis: This muscle allows you to move your big toe away from the other toes.
- Flexor Digitorum Brevis: This muscle helps you flex, or curl, your second through fifth toes.
- Abductor Digiti Minimi: This muscle enables you to move your little toe away from the other toes.
Plantar Aspect – Second Layer (Bottom of Foot)
- Quadratus Plantae: This muscle helps flex your toes.
- Lumbricals: These muscles flex your metatarsophalangeal joints (where your toes meet your foot) and extend your interphalangeal joints (the joints within your toes).
Plantar Aspect – Third Layer (Bottom of Foot)
- Flexor Hallucis Brevis: This muscle flexes your big toe.
- Adductor Hallucis: This muscle allows you to move your big toe toward your other toes.
- Flexor Digiti Minimi Brevis: This muscle flexes your little toe.
Plantar Aspect – Fourth Layer (Bottom of Foot)
- Plantar Interossei: These muscles help you adduct, or bring together, your toes.
- Dorsal Interossei: These muscles abduct, or move apart, your toes.
Plantar Fascia and the Windlass Mechanism
The plantar fascia is a thick band of tissue that runs along the bottom (or plantar surface) of your foot. It’s a crucial structure for support and movement.
One of the plantar fascia’s main jobs is to support the medial longitudinal arch – that’s the arch on the inside of your foot. Think of the plantar fascia as a strong, flexible cable that helps maintain the arch’s shape.
Now, here’s where it gets interesting: the “windlass mechanism.” When you bend your toes upwards (dorsiflexion), it tightens the plantar fascia. This tightening action raises the arch of your foot, making it more rigid and stable. This is especially important when you’re pushing off the ground during walking, running, or jumping, because it provides a stable lever for propulsion.
Nerves of the Foot and Ankle
The nerves in your feet and ankles send signals to help you move and feel sensations. Here’s a brief overview:
- Tibial Nerve: This nerve splits into the medial and lateral plantar nerves.
- Medial Plantar Nerve: This nerve controls muscles on the inside of your foot and gives feeling to your inner toes.
- Lateral Plantar Nerve: This nerve controls muscles on the outside of your foot and gives feeling to your outer toes.
- Deep Peroneal Nerve: This nerve controls muscles in the front of your lower leg and gives feeling to the skin between your big toe and the toe next to it.
- Superficial Peroneal Nerve: This nerve controls muscles on the side of your lower leg and gives feeling to the top of your foot.
- Sural Nerve: This nerve gives feeling to the outside of your foot and ankle.
- Saphenous Nerve: This nerve gives feeling to the inside of your foot and ankle.
Medial Plantar Nerve Entrapment: Jogger’s Foot
The medial plantar nerve is one of the foot’s main nerves. Sometimes, it gets compressed, causing a condition called medial plantar nerve entrapment, or “jogger’s foot.”
Symptoms: If you have jogger’s foot, you may feel pain, numbness, tingling, or burning on the inside of your foot and in your toes.
Causes: Jogger’s foot is often caused by overuse, wearing shoes that are too tight, or having a foot deformity that puts pressure on the nerve.
Diagnosis and Treatment: Doctors can usually diagnose jogger’s foot with a physical exam and nerve conduction studies. Treatment options range from conservative measures like rest, ice, and orthotics, to surgery in severe cases.
To Conclude
The foot is an intricate structure of tendons, ligaments, and muscles, all working in concert to give you stability, mobility, and support. As you’ve seen in the foot tendons diagram, numerous tendons connect the muscles in your lower leg to the bones in your foot.
That’s why a strong understanding of foot anatomy is essential if you want to diagnose and treat foot and ankle conditions. By identifying the specific tendons involved and understanding their function, healthcare professionals can develop targeted interventions to restore optimal foot function and alleviate pain.