Foot & Ankle
Foot and Ankle Anatomy
The foot and ankle is a complex joint involved in movement and providing stability and balance to the body. The foot and ankle consists of 26 bones, 33 joints, and many muscles, tendons and ligaments.
Bones of the Ankle
The ankle joint connects the leg with the foot, and is composed of three bones: tibia, fibula and talus. The tibia or shin bone and fibula or calf bone are bones of the lower leg which articulate with the talus or ankle bone, enabling up and down movement of the foot.
Three bony bumps present on the ends of the tibia and fibula form parts of the ankle joint:
- The Medial malleolus, formed by the tibia, is found on the inside of the ankle;
- Posterior malleolus, also formed by the tibia, is found at the back of the ankle and the
- Lateral malleolus, formed by the fibula, is found on the outer aspect of the ankle
Bones of the Feet
The foot acts as a single functional unit, but can be divided into three parts: the hindfoot, midfoot and forefoot.
The hindfoot forms the ankle and heel and is made up of the talus bone and calcaneous or heel bone. The heel bone is the largest bone in the foot.
The midfoot connects the hindfoot to the forefoot, and consists of one navicular bone, one cuboid bone, and three cuneiform bones. The navicular bone is found in front of the heel bone, and the cuneiform and cuboid bones are arranged in front of the navicular bone.
These bones are connected to five metatarsal bones of the forefoot, which form the arch of the foot for shock absorption while walking or running. The forefoot is also made up of the toes or digits, formed by phalanges, three in each toe, except the big toe, which has only two phalanges. The big two has two additional tiny round sesamoid bones in the ball of the foot, which help in upward and downward movement of the toe.
Ankle and Foot Joints
There are 33 joints in the ankle and foot. They include the
- Hinge joints in the ankle, which allow flexion (bending) and extension
- Gliding joints found in the hindfoot, which allow gliding movements
- Condyloid joints found in the forefoot and toes, which allow the flexion (bending) and extension, adduction and abduction (sideward movement).
The joints of the foot and ankle provide stability and support the weight of the body, helping you to walk or run, and to adapt to uneven ground.
The joint surface of all bones of the ankle and foot are lined by a thin, tough, flexible, and slippery surface called articular cartilage, which acts as a shock absorber and cushion to reduce friction between the bones. The cartilage is lubricated by synovial fluid, which further enables smooth movement of the bones.
Soft Tissues of the Ankle and Foot
Our feet and ankle bones are held in place and supported by various soft tissues such as cartilage, ligaments, muscles, tendons and bursae.
Cartilage is the flexible, shiny, smooth tissue on the ends of bones that meet to form a joint. Cartilage provides cushioning between the bones allowing smooth movement.
Ligaments are tough rope-like tissue that connect bones to other bones, and holds them in place providing stability to the joints. The Plantar fascia is the largest ligament in the foot, originating from the heel bone to the forefoot, it extends along the bottom surface of the foot and is involved in maintaining the arch of the foot. The plantar fascia ligament stretches and contracts to provide balance and strength to the foot. Lateral ligaments on the outside of the foot and medial ligaments on the inside of the foot provide stability and allow up and down movement of the foot.
The foot is made up of 20 muscles, which help in movement. The main muscles include:
- Anterior tibial muscle: allows up and down movement of the foot
- Posterior tibial muscle: supports the arch
- Peroneal tibial muscle: controls movement on the outside of the ankle
- Extensors: enable the ankle to raise the toes just before stepping forward
- Flexors: stabilize the toes against the floor
Smaller muscles are also present to help the toes lift and curl.
Tendons are soft tissues that connect muscles to bones. The largest and strongest tendon in the foot is the Achilles tendon, present at the back of the lower leg around the heel bone. Other tendons include peroneals and anterior and posterior tibialis.
Bursae are small fluid filled sacs that decrease friction between tendons and bone or skin. Bursae contain special cells called synovial cells that secrete a lubricating fluid.
A sprain is the stretching or tearing of ligaments, which connect adjacent bones and provide stability to a joint. An ankle sprain is a common injury that occurs when you suddenly fall or twist the joint or when you land your foot in an awkward position after a jump.
Achilles tendon is a strong fibrous cord present behind the ankle that connects the calf muscles to the heel bone. It is used when you walk, run and jump. The Achilles tendon ruptures most often in athletes participating in sports that involve running, pivoting and jumping.
Plantar fasciitis refers to inflammation of the plantar fascia, a thick band of tissue that lies at the bottom of the foot. It runs from the heel bone to the toe and forms the arch of your foot. Plantar fasciitis is one of the most common causes of heel pain. It is most often seen in middle-aged men and women, but may also occur in those who are constantly on their feet such as soldiers.
The ankle joint is composed of three bones: the tibia, fibula, and talus which are articulated together. The ends of the fibula and tibia (lower leg bones) form the inner and outer malleolus, which are the bony protrusions of the ankle joint that you can feel and see on either side of the ankle.
Ankle instability is a chronic condition characterized by a recurrent slipping of the outer side of the ankle. It usually results from repeated ankle sprains. It is generally noticed during movement of the ankle joint but can also occur during standing as well.
The nail is composed of a nail plate, nail matrix and nail bed. The nail bed is the soft tissue that lies below the nail and is essential for the growth of the nail. Nail bed injuries such as crush and avulsion injuries are commonly associated with injuries to the hands or fingertips.
The ankle joint is an articulation of the end of the tibia and fibula (shin bones) with the talus (heel bone). Osteochondral injuries, also called osteochondritis dissecans, are injuries to the talus bone, characterized by damage to the bone as well as the cartilage covering it. Sometimes the lower end of the tibia or shin bone may also be affected.
The calcaneus or heel bone is a large bone found at the rear of the foot. A fracture is a break in a bone from trauma or various disease conditions. The types of fracture to the calcaneus depend on the severity and include stable fractures, displaced fractures, open fractures, closed fractures and comminuted fractures.
The Lisfranc joint or tarsometatarsal joint refers to the region in the middle of the foot. It is a junction between the tarsal bones (seven bones in the foot arch) and metatarsal bones (five long bones in the foot). Lisfranc fracture scan occur due to a fall from a height or traumatic motor accidents.
The talus is a small bone at the ankle joint that connects the heel bone and the shin bones, enabling the up and down movement of the foot. Fractures in the talus bone may occur due to a fall from great heights, motor vehicle accidents or sports injuries. Symptoms include severe ankle pain, inability to walk, swelling and tenderness.
Turf toe is an injury to the ligament at the base of the big toe. It is a painful condition which usually results from jamming of the toe into the ground or excessive backward bending of the toe. As it is more common in athletes playing on artificial turf, especially those involved in field sports such as football, baseball and soccer, it is known as turf toe.
Ankle ligament injury, also known as ankle sprain, can be caused by a sudden twisting movement of the foot during any athletic event or during daily activities. It is one of the most common orthopaedic injuries and can also be caused by walking down a slope or over any uneven surface. The injury can range from mild to severe, depending on the condition of the injured ligament and the number of ligaments involved.
Osteochondral injuries are one of the most common causes of ankle pain. Though in most cases there is a history of injury or trauma to the ankle joint, a few cases may not have any previous history of ankle injury. A condition known as osteochondritis dissecans is commonly seen in the knee and ankle joint and is characterized by the damage and separation of a piece of bone and cartilage, within the joint, from the underlying bone.
Arthritis is inflammation resulting from the degeneration of cartilage in the joint causing pain, swelling, and stiffness in the joints resulting in restricted movements. Arthritis of the foot and ankle joint can occur due to fracture, dislocation, inflammatory disease, or congenital deformity.
Forefoot pain, also referred to as metatarsalgia, is a type of pain that occurs in the ball of the foot (around the tip of the metatarsal bones). Generally, forefoot pain is associated with aging. Individuals with metatarsalgia experience pain of varied intensity and discomfort and find difficulty in activities like walking, running, playing, and several others.
In toeing also called “pigeon-toed”, is an abnormal condition characterized by inward facing of the toe or feet instead of being straight. Parents may observe their children having intoeing at an early age when they start walking. But usually intoeing corrects itself without any specific treatment as the child grows up to around 8 years of age.
Flatfoot, also known as “fallen arches” or Pes planus, is a deformity in children’s feet in which the arch that runs lengthwise along the sole of the foot has collapsed to the ground or not formed at all. Flatfoot is normal in the first few years of life as the arch of the foot usually develops between the age of 3 and 5 years. Flatfoot can be rigid or flexible.
Fungal infections are common in nails, and occur most often in toe nails. Termed as onychomycosis, nail fungus affects the keratin, the hard material that makes up the nail and can include the entire nail or a portion of the nail, along with the nail root, plate or bed. It gradually leads to thickening, distortion and discoloration of the nails.
Foot drop also known as drop foot, is a sign of an underlying muscular, neurological or anatomical condition, where you are unable to lift the front part of your foot, resulting in foot dragging. To avoid dragging your foot, you may lift your knee higher than usual as if you were climbing stairs or swing your leg in a wide arc, causing you to slap your foot on the ground every time you step forward. Foot drop may also produce numbness. It can affect one or both feet and may be temporary or permanent.
A hammertoe is a deformity of a lesser toe (second through fifth toes), where the toe gets bent upward at the toe’s middle joint, resembling a hammer. The bent portion may rub against a shoe causing pain, irritation and development of corns. It is caused by wearing shoes that are too tight or narrow near the toes, when the second toe is larger than the first, and as a complication of arthritis and certain neuromuscular conditions.
Mallet finger is a condition where the end of the finger is bent and does not straighten. It occurs when the extensor tendon on the back of the finger is damaged. The finger joint is a hinge-joint that allows bending and straightening of the fingers. Each finger is composed of 3 phalanges bones, joined by 2 interphalangeal joints (IP joints). The joint near the base of the finger is called the proximal IP joint or PIP joint, and the joint near the tip of the finger is called the distal IP joint or DIP joint.
Claw toe is a deformity, where a toe bends and appears like a bird’s claw. The affected toe is bent upward from the joint at the ball of foot, and downward at the joints in the middle and tip of the toe to curl under the foot. Hard thick skin called corns may develop under the ball of the foot or on the top of the affected toe, causing pain while walking.
Congenital deformities of the lower limbs are developmental disorders that are present at birth, causing alterations in the shape and appearance of the legs. Several factors such as genetics, teratogenic drugs and chemicals can cause congenital deformities.
A corn is a circular area of thickened skin developed because of continuous friction or pressure. They usually develop on the soles of feet, or on the top or sides of toes, and appear as yellowish dead tissue surrounding an area of tenderness. Pain and discomfort may be present with walking, which can get more painful without treatment.
A bunion, also known as hallux valgus, is bony prominence at the base of the big toe, which often results in pain, redness and rubbing in footwear. The 1st metatarsal bone abnormally angles outward towards the other foot from its joint in the midfoot. A bunion can change the shape of your foot, make it difficult for you to find shoes that fit correctly and worsen the symptoms if left untreated.
Foot reconstruction is a surgery performed to correct the structures of the foot and restore the natural functionality of the foot that has been lost due to injury or illness. Ideally, any foot surgery for reconstruction is done to improve the appearance and function of the foot so that patients can maintain their quality of life.
Subtalar arthrodesis is the surgical fusion of bones that form the subtalar joint. The subtalar joint is a complex joint located below the ankle joint and is formed by the union of the heel (calcaneus) and the talus (ankle) bone. The subtalar joint allows side-side movement of the foot.
Minimally Invasive Foot Surgery (MIFS) uses the latest advanced technology to treat foot and ankle pain caused by a variety of conditions. Special surgical instruments, devices and advanced imaging techniques are used to visualize and perform the surgery through small incisions. The aim of MIFS is to minimize damage to the muscles and surrounding structures enabling faster recovery and less pain.
Injuries during sports are common. They can result from accidents, inadequate training, improper use of protective devices, or insufficient stretching or warm-up exercises. Injuries to the foot and ankle are common while playing sports such as football, hockey, skating and in weekend athletes. Common sports injuries include sprains and strains, ankle fractures, and Achilles tendinitis.
To support the entire body’s weight on your two feet, the inner middle portion of each foot (midfoot) is raised off the ground to form an arch. A cavovarus foot deformity is characterized by a higher-than-normal arch of the inner midfoot. This results as the two ends of the foot - the heel and toes - abnormally draw towards the inside of the foot, causing the foot to rest on its outer side.
Ankle tenotomy is a surgical procedure to lengthen the Achilles tendon enabling the ankle to flex upward and allowing the heel to be placed flat on the floor. It is indicated in patients that have an abnormally developed Achilles tendon or one that has become shortened and difficult to stretch. The surgery is done to restore the normal range of motion of the ankle.