Ankle¶
Return to Table of Contents¶
The Ankle
Bimalleolar Fracture (Potts or Dupuytren)
Ankle Overview¶
The ankle joint is formed by the connection of three bones. The ankle bone is called the talus. The top of the talus fits inside a socket that is formed by the lower end of the tibia (shinbone) and the fibula (the small bone of the lower leg). The bottom of the talus sits on the heel bone, called the calcaneus.
The talus works like a hinge inside the socket to allow your foot to move up and down.
Inside the joint, the bones are covered with a slick material called articular cartilage. Articular cartilage is the material that allows the bones to move smoothly against one another in the joints of the body.
The tibia and fibula have specific parts that make up the ankle:
· Medial malleolus: Inside part of the tibia
· Posterior malleolus: Back part of the tibia
· Lateral malleolus: End of the fibula
The ligaments of the ankle joint are grouped in two categories
· The lateral collateral ligaments (lateral means further away from the center of the body)
· The medial collateral ligaments or deltoid ligament (the side closest to the other ankle)
(Note: the medial and collateral ligaments can also refer to the knee)
Lateral collateral ligaments include
· Anterior talofibular ligament (ATFL)
· Calcaneofibular ligament (CFL)
· Posterior talofibular ligament (PTFL)
Medial collateral ligaments or deltoid ligaments
· Tibionavicular ligament
· Calcaneotibial ligament
· Anterior/Posterior talotibial ligament
Two joints are involved in ankle fractures:
· Ankle joint
· Syndesmosis: The joint between the tibia and fibula, which is held together by ligaments. The ligaments support the lower end of the leg where it forms a hinge for the ankle. This series of ligaments supports the ankle syndesmosis, the part of the ankle where the bottom end of the fibula meets the tibia.
· Three main ligaments support this area:
o Anterior Inferior Tibiofibular Ligament (AITFL) is the ligament that crosses just above the front of the ankle and connecting the tibia to the fibula
o Posterior Fibular Ligaments attaches across the back of the tibia and fibular
§ The above ligaments include the posterior inferior tibiofibular ligament (PITFL) and the transverse ligament
o ** __** Interosseous ligament lies between the tibia and fibula (Interosseous means between bones). This ligament is a long sheet of connective tissue that connect the entire length of the tibia and fibula, from the knee to the ankle
· The ligaments that surround the ankle joint help form part of the joint capsule.
· The ankle joint is also supported by nearby tendons. The large Achilles tendon is the most important tendon for walking, running and jumping. It connects to the heel of the calf muscles.
Bimalleolar Fracture¶
· Also known as: Potts or Dupuytren fracture
· A bimalleolar fracture is a fracture of both the lateral and medial malleolar
· To locate the injury via freeform search, enter ‘bimalleolar fx’ right or left and open or closed
· The code for ‘bimalleolar fx closed’ is 824.4.L/R and ‘bimalleolar fx open’ is 824.5.L/R
Malleolus Fracture¶
· Malleoli are the distal (bottom) ends of the tibia and fibula
· The Medial malleolus is the distal end of the tibia
· The Lateral malleolus is the distal end of the fibula
· The code for ‘medial malleolus fx closed’ is 824.0.L/R and ‘medial malleolus fx open’ is 824.1.L/R
· The code for ‘lateral malleolus fx closed’ is 824.2.L/R and ‘lateral malleolus fx open’ is 824.3.L/R
Subtalar Fracture¶
· Subtalar fracture is entered in the system using fracture of the talus
· To locate the injury via freeform search, enter ‘fx talus’ right or left and open or closed
· Closed talus fracture code is 825.21.L/R; Open talus fracture code is 825.31.L/R
· The Medical Library defines the subtalar fracture as part of the talus
· The talus consists of three parts: a head, neck and a body
· The body of the talus is the part that fits into the socket created by the lateral and medial malleoli
· The lower part of the body connects with the calcaneus to form what is known as the subtalar joint
· The talar neck connects with the navicular bone while the head also forms part of the subtalar joint
Torn Tibiofibular Ligament¶
· This is entered using the sprain/strain codes specific to the tibiofibular ligament
· The root code for this injury is 845.03
Trimalleolar Fracture¶
· A trimalleolar fracture is a fracture of the lateral (fibula) and medial (tibia) malleoli and the posterior portion of the tibia (posterior malleolus)
· To locate the code using freeform search enter ‘trimalleolar fracture’ to refine the search enter ‘right or left’ and whether it is ‘opened or closed’ fracture
· Closed trimalleolar fracture code is 824.6.L/R ; opened trimalleolar fracture code is 824.7.L/R
· If a trimalleolar fracture is diagnosed and a dislocation of the talus, enter both codes
¶
Talus Dislocation¶
· The talus is situated between the heel bone and the tibia and fibula. Based on its’ proximity to the tibia and fibula, it is often susceptible to dislocation when a trimalleolar fracture occurs
· To locate the code for a talus dislocation using freeform search, enter ‘tarsal dislocation’ as an injury; you can further refine search by entering ‘right or left’ and whether it is an ‘open or closed’ dislocation
· ‘Closed talus dislocation’ code is 838.01.L/R ; ‘open talus dislocation’ code is 838.11.L/R
· If a dislocation of the talus is diagnosed in addition to a trimalleolar fracture, enter both injuries in the system
¶
Talus Fracture¶
· The talus is a small bone that sits between the heel bone (calcaneus) and the two bones of the lower leg (tibia and fibula). It has an odd humped shape.
· A talus fracture occurs when the talar bone, one of the important connections between the leg and the foot, is broken.
· A talus fracture often requires surgery, and even with surgical treatment, patients often have long term ankle problems such as arthritis
· ‘Closed talus fracture’ code is 825.21.L/R ; ‘open talus fracture’ code is 825.31.L/R
· To locate using freeform search enter keyword ‘fx talus’ to refine search enter ‘closed or open’ and ‘right or left’, select Injury and then Find