More Effective Joint: Sprained Ankle

     The ankle is composed of many different bones and joint, with ligaments connecting them to each other, that bind and work together to allow us to walk and move our feet. There are ligaments surrounding the ankle and they act to stretch and allow the ankle to move up and down or side to side. Because it is able to do this, the ankle is namely called a subtalar joint. After investigating more into ankle injuries and where the damage is sourced and what is affected, I have proposed a newly designed ankle that will minimize rolled ankles and decrease the number of injuries. If you're interested in how this super-ankle can prevent sprains and resist impact, keep on reading!

The ankle is located at the bottom of the tibia and fibula: bones that make up your lower leg. The “true ankle” consists of three bones: the calcaneus, talus, tibia, and fibula. These three joints are responsible for the up-and-down motion of the ankle. The calcaneus is the cuboidal structured bone at the back of your foot, making up the rounded portion of your ankle. The talus makes up the lower portion of the ankle joint; the tibia and fibula are part of the lower leg, the tibia being the larger bone. Among these bones in your ankle, there are ligaments that connect them to each other. When walking, the talus takes on the entire weight of the body primarily, then trasnfers the half of the weight to the calcaneus.

Here is an overview of the commonly torn ligaments during an ankle sprain or injury. The three ligaments that make up the lateral ligament complex is the anterior talofibular ligament (ATFL), the calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL). THis complex gives the ankle lateral stability when walking, running, or jumping. The anterior talofibular ligament is located between your fibula and tibia, stretching across the upper region of your foot. The ATFL connects the fibula to the metatarsals, stretching sagittally across the foot. The calcaneofibular ligament (CFL) connects the middle of the calcaneus to the base of the fibula. The posterior talofibular ligament (PTFL) attach between the backs of the tibia and fibula. Lastly, the deltoid ligaments connect the tibia to talus/calcaneus providing medial stability. The underside of the talus and the top of the calcaneus forms the subtalar joint, allowing the ankle to move side-to-side. The ankle works like a hinge joint giving it the ability to move up (dorsiflexion) and down (plantarflexion).

A tendon connects a muscle to a bone. Beginning at the fibula and stretching down around the top of the calcaneus are the peroneals, ending towards the tarsals is the peroneus brevis tendon; the longer tendon, peroneus longus tendon lies underneath the PBT. The most popular and commonly known tendon in is the Achilles tendon, attaching the calf muscles to the calcaneus. This allows us to going onto our tippy toes and is critical for walking and engaging the muscles in our lower leg.

There is a nerve that passes over the middle of the top of the foot, one along the outer edge of the ankle, and the tibial nerve which runs behind the medial malleolus. These nerves provide the foot with sensation and allow the foot to better control the muscles surrounding it. Arteries supply blood and oxygen to the foot joint. The artery located over the superior face of the foot is the dorsalis pedis and the artery behind the medial malleolus is the posterior tibial artery, which transmits other smaller vessels to the interior of the ankle joint.

Often when an ankle injury occurs, the ligaments located on the outer edge of the ankle stretch beyond their capacity and tear. During dance, the body is everted to its full capacity, as the core, and limbs are highly engaged and actively moving. When one does a leap, the leg comes back down with the ankle facing the initial impacts. If landed incorrectly or at a strange position, the ankle may roll and the ligaments tear causing a painful sprain and the ankle to turn inward. Ankle sprains, causing the foot to turn in are common in sports such as soccer and football since your legs are rapidly moving.

Most common, the three ligaments(anterior talofibular ligament (ATFL), the calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL) in the lateral ligament complex tear during a rolled ankle. As seen by the picture below, the red marks indicate where the tear would take place.

Most common, the three ligaments(anterior talofibular ligament (ATFL), the calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL) in the lateral ligament complex tear during a rolled ankle. As seen by the picture below, the red marks indicate where the tear would take place. Since these ligaments on the lateral side of the ankle often tear during injury, my proposal for the new ankle is to thicken the fibers in each of those ligaments, making them sustain more impact that they usually do. The ligaments will also be more elastic, allowing them to stretch farther during an impact and resist snapping. By increasing the thickness of the ligaments and increasing their tolerance for sudden impact, the ankle may appear thicker in size, however this will still benefit the foot because it gives more cushion and catches some of the injury's impact. 
     Along with the thickening the ligaments, there will also be a layer of fat added below the calcaneus, underneath the metatarsals and tarsals. This will give the foot more stability when doing everyday motions such as walking, but will greatly benefits athletes because it also prevents the ankle's joints from receiving the impact and instead transfers it to the added fat. The new fat will be called "calcaneotarsal filament."
     Finally, the ankle's talus and base of the tibia and fibula will be able to rotate 360 degrees. This motion will allow the ankle to smoothly move along any disturbances of turning in or turning out, giving the ankle more relaxed momentum to resist any injuries that may cause it to twist abnormally. 

     I arrived at this new design because I noticed a repetition of broken ligaments during a rolled ankle. Not only were they usually ligaments, but the ones that tore were always located on the lateral side of the ankle. Also, the ankle was usually turned inwards during an sports injury, therefore I decided that adding a rotating cuff into the talus and base of tibia and fibula would allow the ankle to resist that impact of turning in. I had some issues with adding in the new layer of fat into the bottom of the ankle since it would be impossible to add any kind of material into joints and bones, however, it fit the requirements of increasing protective cushion in the ankle. It was interesting to go through the process of looking deeper into the ankle, as it is often said that studying the dysfunctions of our body helps us understand the normal functions. And it is true! I was fascinated about the various ligaments in the ankle and how precisely each one was located. Seeing that injuries often caused the lateral side of the ankle to break, shows how important it is to be mindful of where our foot placement is. When we participate in various activities such as dance, soccer, football, or any kind of sport, our ankle is under a large amount of impact and we can decrease the risk of injury by always landing either toes first, or (keeping) the knees bent so that the impact distributes up the leg and isn't all located in the ankle.    

Works Cited: 

“Anatomy of the Ankle.” Southern California Orthopedic Associates, www.scoi.com/specialties/anatomy-ankle. Accessed 8 May 2017.

Fisher, Stuart James, editor. “Foot and Ankle.” OrthoInfo, American Academy of Orthopedic Sciences, 2017, orthoinfo.aaos.org/topic.cfm?topic=A00524.

FootCare MD, editor. “Ankle Sprain.” American Orthopedic Foot & Ankle Society, Bone and Joint Initative, 2017, www.aofas.org/footcaremd/conditions/ailments-of-the-ankle/Pages/Ankle-Sprain-.aspx.

Johnson, Josh. “Ankle Sprain.” My Ankle, edited by British Orthopaedic Foot & Ankle Society., General Medical Council, 2013, myankle.co.uk/conditions/ankle-sprain/. Accessed 5 May 2017.

“A Patient’s Guide to Ankle Anatomy.” Where Does It Hurt, Houston Methodist Leading Medicine, 2017, www.houstonmethodist.org/orthopedics/where-does-it-hurt/ankle/ankle-anatomy/. Accessed 8 May 2017.

Tortora, Gerald J., and Bryan Derrickson. Introduction to the Human Body. 7th ed., John Wiley & Sons, 2007. The Essentials of Anatomy and Physiology.