Ankle Joint - Bones, Joints, and Muscles Flashcards
Name 4 bony landmarks on the tibiofibular regions of the ankle joint
- Triangular subcutaneous area (Articulating surface of the Tibia and Fibula)
- Lateral Malleolus
- Medial Malleolus
- Trochlear Notch
What are the bones in the heel of the ankle joint?
What is the shape of the articulating surface?
The Talus (Articulating surface) and Calcaneus *The articulating surface is convex*
What are the bones of the mid foot?
3 Cuneiforms (medial), Navicular, Cuboid (lateral)
What are the bones of the fore foot?
Metatarsals and Phalanges from the 1st to 5th digit
What are the ligaments of the medial side of the ankle joint?
All these ligaments originate from the Medial Malleolus and collectively called the Deltoid ligament:
- Posterior Tibiotalar (Deep)
- Anterior Tibiotalar (Deep)
- Tibiocalcaneal (Posterior and distally attaches to the Sustentaculum Talus)
- Tibionavicular (Anterior)
- Spring ligament (Plantar Calcaneonavicular) Supports the arch of the foot and doesn’t come from the medial malleolus
What is the Sustentaculum Talus?
A bony prominence on the medial side of the calcaneus and is a location for ligament attachment and prevents the ankle slipping medially
What are the ligaments of the lateral aspect of the ankle joint?
- Posterior Talofibular
- Anterior Talofibular
- Calcaneofibular
- Bifurcated ligament (Calcaneocuboid & Calcaneonavicular)
Which side of the ankle, medially or laterally, is the most vulnerable to injury and why?
What position of the ankle is the most likely to get a sprain?
- The Lateral side: This is because there are fewer, thinner, ligaments in this region than on the medial side.
- Plantar flexed and inverted because the anterior talofibular ligament and the talus medially is put under a lot of tension and pushed by the bone.*
What is the subtalar joint made up of?
What movement does it perform?
What are the primary ligamentous attachments?
- The Talus and Calcaneus
- Adduction with plantar flexion, and medial rotation
- Abduction with dorsiflexion, and lateral rotation
- The Interosseous ligaments, they are located in the sinus tali which is hollow tube though the foot
What type of synovial joint is the Midtarsal (Talocalcaneonavicular) joint? Why?
Ball and Socket - This is because the articular surface on the Calcaneus is convex (inferiorly), as well as the head of Talus (Superiorly), and the Navicular is concave (Main articulating bone)
What is significant about the Spring ligament in the Midtarsal ligament?
The Spring ligament, coming from the Sustentaculum Talus to the navicular, has a part of the articulating surface. To make this movement easier the ligament is cartilaginous to reduce friction which allows more fluid movement.
It also is the primary support for the medial arch of the foot.
What is the lateral aspect of the Midtarsal joint (Calcaenocuboid joint) and what movements can it perform?
The calcaneocuboid joint, the cuboid glides with calcaneus inferiorly and superiorly
What are the other three types of joints in the foot, and name examples?
- Tarsometatarsal joints, they are Plane joints which create slight gliding movements
- Metatarsophalangeal joints, they are Condylar joints which perform flexion and extension as well as abduction and adduction.
- Interphalangeal joints (Proximal and Distal), they are hinge joints.
What are movements of Mid foot?
Inversion:
- Adduction of the calcaneus at the subtalar joint
- Supination of the forefoot at the midtarsal joint
Eversion:
- Abduction of the calcaneus at the subtalar joint
- Pronation of the forefoot at the midtarsal joint
What are the ligaments of the plantar foot?
What are their functions and what are the insertions?
- Spring ligament (Plantar Calcaneonavicular)
- Plantar Calcaneocuboid ligament: It is longer than the spring ligament, and supports the lateral arch of the foot. Originates on the inferior aspect of the calcaneus and travels to plantar surface of the cuboid.
- Long Plantar ligament: It is the longest foot ligament and supports all the joints it passes as it originates in the tubercles of the calcaneus through midline to the bases metatarsals of 2, 3 & 4.
What are the 4 anterior crural muscles?
- Tibialis Anterior
- Extensor Hallucis Longus
- Extensor Digitorum Longus
- Peroneus Tertius
How does the body protect the long tendons of the anterior crural muscles?
What are its attachments?
Extensor Retinaculi is thickened fascia which binds the tendons in the joint; there are two parts of the extensor retinacula:
- upper component: starts on the shafts of the tibia and fibular around the anterior of the joint.
- lower component: comes from the fibula malleolus around anterior to the calcaneus*