The ankle and foot regions belong to the body’s lower extremities or lower limbs. These parts support the upper body’s weight, maintain balance, and allow various movements(1).
The ankle is part of the lower limb that encompasses the leg’s distal portion and the foot’s proximal portions. The ankle joint (talocrural joint) allows the foot’s dorsiflexion (raising the foot upwards) and plantar flexion (pointing the foot downwards)(2).
Three joints comprise the ankle joint: tibiotarsal (upper ankle joint), talocalcaneonavicular, and subtalar joints. The last two joints are also called the lower ankle joints(3).
The interior surfaces of the tibia (shinbone), fibula (calf bone), and the superior surface of the talus make up the upper ankle joint. Meanwhile, the talus (ankle bone), calcaneus (heel bone), and navicular bone form the lower ankle joint.
The joints are supported by a set of ankle ligaments: the medial collateral or deltoid ligament and lateral collateral ligament(4).
There are 26 bones in the foot divided into tarsal bones, metatarsal bones, and phalanges(5).
Tarsals consist of seven irregularly shaped bones that make up a strong weight-bearing platform. These bones are homologous to the carpal bones in the wrist and are divided into three groups(6):
Five metatarsals connect the distal aspects of the cuneiform bones and cuboid bone to the base of the foot’s phalanges supporting the body’s weight(7). Metatarsal bones are homologous to the metacarpals of the hand.
Phalanges are bones that make up the fingers and toes. There are 56 phalanges in the body, with 14 on each hand and foot.
The lateral four toes consist of three phalanges (proximal, middle, and distal). Meanwhile, the hallux (great toe) consists of only two phalanges (proximal and distal)(8).
Aside from the ankle joint that connects the foot with the leg, the foot’s bones articulate among themselves through numerous synovial joints(9).
A synovial joint is a common joint type wherein the articulating surfaces have no direct contact with each other. The four groups of foot joints are: intertarsal, tarsometatarsal, metatarsophalangeal, and interphalangeal(10).
The foot muscles contribute to the toes’ movements, the foot’s plantar flexion, dorsiflexion, eversion, and inversion(11).
In eversion, the sole of the foot is turned and faces laterally. Meanwhile, the sole is directed medially during inversion(12).
The foot muscles are divided into two groups: plantar and dorsal. The dorsal group has two muscles, while the plantar muscles are further divided into three subgroups: lateral, central, and medial.
The dorsal foot muscles extend the toes and are in the dorsum (area facing upwards while standing). These muscles include the extensor digitorum brevis and extensor hallucis brevis(13).
The deep fascia of the foot is located beneath the subcutaneous tissue, surrounding the intrinsic foot muscles. The three groups of plantar foot muscles are(14):
The standard initial imaging modality to assess the ankle and foot is conventional radiography. It has a superior spatial resolution of osseous (bony) structures compared to magnetic resonance imaging (MRI)(15).
Radiography also offers strong contrast resolution to differentiate between bone, metal, fat, calcification, and soft tissues. This modality provides a detailed anatomic assessment of the bones to help identify and diagnose fractures or injuries(16).
Like radiography, CT utilizes ionizing radiation to generate images. This cross-sectional imaging technique provides a non-invasive method to visualize complex anatomical structures(17).
CT is most commonly used in ankle and foot imaging to characterize complex injuries or detect radiographically occult fractures. CT can easily distinguish metal, bone and calcifications, soft tissues, gas, and fat(18).
MRI is the choice of modality for further imaging the ankle and foot after obtaining initial radiographs.
This imaging technique assesses the ligaments and tendons, neurovascular structures (tarsal tunnel and plantar fascia), and the osseous structures(19).
MRI can detect radiographically occult fractures or ankle impingement syndromes and characterize various injuries(20).
This webpage presents the anatomical structures found on foot radiograph. Elbow Radiograph – Lateral projection 1, Fibula 2, Cuboid 3, 5th Metatarsal Bone 4, Tibia 5, Talus 6, Navicular 7, Cuneiform 8, 1st Metatarsal Bone 9, Proximal phalanx 10, Distal phalanx Elbow Radiograph – Lateral projection 1, Calcaneus 2, Cuboid 3, 5th Metatarsal Bone […]
This webpage presents the anatomical structures found on ankle radiograph. AP projection The Ankle The ankle joint is usually one of the most injured joints and the most common type of fracture treated by orthopedic surgeons(1). Although the ankle is often referred to as a single joint, it consists of the true ankle joint
This webpage presents the anatomical structures found on ankle MRI. sagittal view, T1 axial view, T2FATSAT coronal view, T2FATSAT sagittal view, T2FATSAT sagittal view, T1 MRI of ankle, sagittal view, image 1.1, Tibia (medial malleolus). 2, Navicular. 3, Tibialis anterior tendon. 4, Medial cuneiform. 5, 1st metatarsal. 6, Flexor hallucis brevis muscle. 7, Abductor
MRI of the Ankle: Detailed Anatomy Read More
This webpage presents the anatomical structures found on ankle CT. Coronal view Axial view Sagittal view Coronal view Scout view (coronal reconstructions). CT-scan of the ankle (coronal reconstruction). Image 2. 1, Fibula. 2, Tibia. 3, Talus. CT-scan of the ankle (coronal reconstruction). Image 3. 1, Fibula. 2, Tibia. 3, Talus. CT-scan of the ankle
Anatomy of the Ankle and Foot Read More
