Medial ankle sprains are a less common than lateral ankle sprains, but they can still occur in both the general and sporting populations, and both fall under the general category of a sprained ankle.
A medial ankle sprain involves damage to the medial ankle ligaments, mainly the deltoid ligament, which is located on the inside part of the ankle joint.
In the case of isolated deltoid ligament injuries, you may hear the term “deltoid ligament sprain”, which is simply a more specific description of that particular medial ankle sprain.
While the cause of this ankle injury can be forced ankle eversion in varying degrees of plantarflexion or dorsiflexion, a medial ankle sprain can also occur in combination with other types of ankle sprains, esepcially in traumatic injuries where a specific mechanism of injury cannot be easily defined.
Therefore, having an understanding of the bones, ligaments, and muscles involved in the medial ankle, specifically the deltoid ligament complex, as well as common mechanisms of injury for medial ankle sprains, one can then gain a better understanding of assessment and treatment of their sprained ankle.
Medial Ankle Ligaments
A medial ankle sprain most commonly involves damage to the deltoid ligament complex, which consists of a number of different medial ankle ligaments, primarily:
1. Tibiocalcaneal Ligament
2. Tibionavicular Ligament
3. Posterior Superficial Tibiotalar Ligament
4. Tibiospring Ligament
5. Anterior Tibiotalar Ligament
6. Posterior Deep Tibiotalar Ligament
When reading the names of all these ligaments, it’s understandable to see this more as a jumbled word salad. The main thing to know is that each of these ligaments serves a specific purpose, but they also work as a team to support a large portion of the medial aspect of the ankle.
These medial ankle ligaments can be separated into two compartments, which can often assist students in remembering the different ligaments and their general functions:
Superficial Compartment = Ligaments 1-4 (Tibiocalcaneal, tibionavicular, Posterior Superficial Tibiotalar, and Tibiospring ligaments).
Deep Compartment = Ligaments 5 and 6 (Anterior Tibiotalar Ligament and Posterior Deep Tibiotalar Ligament – also termed the “deep deltoid ligament”).
Medial Ankle Ligament Attachments and Functions
We will describe the deltoid ligament attachments and functions below, as this is the primary medial ankle ligament.
We placed this anatomical information in its own section because it may be more detail than necessary for many of our readers, but we felt it should be included nonetheless, for example, in the case where you are trying to understand an ultrasound report of your ankle injury provided by your physician.
Attachments: Medial malleolus of the tibia to the sustentaculum tali of the calcaneus
Function: Resists forced ankle eversion especially in dorsiflexed positions
Attachments: Medial malleolus of the tibia to the navicular tuberosity
Function: Resists forced ankle eversion, helps to suspend the spring ligament, and assists in stabilizing the head of the talus.
* Some recent literature, for example Gregerson et al (2022), suggest the tibionavicular ligament not be considered a completely distinct ligament of the deltoid ligament complex given the difficulty in distinguishing its fibers from the joint capsule in cadaveric studies.
Posterior Superficial Tibiotalar Ligament
Attachments: Medial malleolus of the tibia to posterior process (medial tubercle) of the talus
Function: Resists forced eversion/excessive valgus movement of the ankle
Attachments: Medial malleolus of the tibia to the spring ligament
Function: Resists forced ankle eversion, particularly in plantarflexion, and provides support to the spring ligament, the latter of which helps to stabilize the medial longitudinal arch of the foot.
Anterior Tibiotalar Ligament
Attachments: Medial malleolus of the tibia to the proximal and medial aspect of the body of the talus
Function: Resists forced ankle eversion and rotation, particularly in plantarflexion.
Posterior Deep Tibiotalar Ligament
Attachments: Medial malleolus of the tibia to the superior/posterior/medial aspect of the talus
Function: Provides medial ankle stability in dorsiflexed positions
What causes a medial ankle sprain?
While medial ankle sprains are not nearly as common as lateral ankle sprains, they do occur in the general population, athletes, and in traumatic scenarios.
Any damage to the deltoid ligament will be considered a medial ankle sprain, and this will typically occur when the force that stretches the ligaments overcomes their normal physiological tensile strength.
Given ligaments have elastic properties, this may not result in a full rupture, but even micro-tearing f the deltoid ligament can have a significant impact on comfort and function.
One relatively easy way to think about a medial ankle sprain mechanism of injury is by considering it the opposite of a lateral ankle sprain.
For example, rolling an ankle is a very common mechanism for a lateral ankle sprain – the outside of the ankle is excessively stretched while the inside of the ankle is not stretched.
Therefore, for a medial ankle sprain, any force that excessively stretches the inside of the ankle joint, which is where the deltoid ligament and other medial ankle ligaments are located, can result in a medial ankle sprain. Generally speaking, this means the medial ankle is most vulnerable with forced eversion.
Less intuitively, a combination of supination and external rotation can often result in injury to the deltoid ligament as well as a fracture to the fibula, which can make understanding medial ankle sprains a little confusing.
Given each specific ligament comprising the deltoid ligament complex is most taught in different degrees of plantarflexion/dorsiflexion, inversion/eversion, and internal/external rotation, there is a spectrum of ankle positions that can lend the ankle to being vulnerable to medial sprains, which is why there is no single defined mechanism of injury.
For the sake of simplicity, understanding that forced ankle eversion stresses the medial aspect of the ankle is a solid starting point.
It’s understandable if this is hard to picture. If you stand up and visualize rolling your ankle versus trying to stretch the inside of the ankle, it can become more intuitive why a medial ankle sprain is less common.
In my clinical experience, I’ve seen medial ankle sprains occur mostly when landing from a jump on an uneven surface where the inside of the ankle is stretched, landing from a jump while the body is in motion in space (planted ankle on landing while body moves over ankle), or in highly traumatic experiences where the entire ankle is basically injured.
In the case of jumping, landing on uneven surface, or planting the foot while your body is still moving over top of it, are usually the most common mechanisms of injury.
The risk of a medial ankle sprain increases if the athlete is also intending to plant and cut, or if an opponent lands on their leg while the ankle joint is in an everted position.
Another case example was a young short track speed skater who caught an edge at high speed and crashed with multiple other skaters landing on her. Catching the edge of the skate at high speed produced a rotational force on the ankle, and then the force of different skaters landing on her added additional force to the ankle in a very awkward manner.
Both of these cases were relatively minor and successfully treated with physiotherapy, whereas cases such as car accidents and falls from extreme heights more often require surgery, especially considering these are typically combined with other severe lower extremity injuries as well.
Treatment for a Medial Ankle Sprain
Just like any other low ankle sprain, most medial ankle sprains can be managed with conservative care, such as physiotherapy, which also serves to provide a long term reduction in risk of re-injury. For the sake of the following discussion, we will assume that there is no fracture associated with the injury.
Initial Recovery Stages
In the initial stages of recovery, especially for severe ankle sprains and other severe ankle injuries, there will be focus on providing an optimal healing environment for the ankle joint so the deltoid ligament and surrounding tissues can recover enough to lay the groundwork for subsequent phases of rehab.
This may include strategies like the P.R.I.C.E. principle, and perhaps some gentle active range of motion and/or proprioception exercises within the tolerable limits of the deltoid ligament. Range of motion should be performed within pain-free limits that do not place excessive stretch on the medial ankle.
Strength and Non-Weight Bearing Rehab Stage
As the ankle continues to recover and the tissue now enters the proliferative stage of healing, we can now begin to place a little more demand on the ankle joint while still protecting the deltoid ligament.
This may include strengthening in non-weight bearing positions with resistance bands, whereby we strengthen all the muscles around the ankle without stretching the deltoid ligament too much, which will help work towards resolving any ankle instability.
For example, if someone’s mechanism of injury for their deltoid ligament sprain was purely forced eversion, then we may wait a little longer to strengthen the peroneal muscles through full range of motion in order to avoid stretching the deltoid ligament, and instead may focus on supporting the inside of the ankle by strengthening muscles responsible for inversion.
Weight Bearing Rehab Stage
If weight bearing can be sufficiently tolerated, it may be appropriate to begin with static double-leg or single-leg balance and proprioception exercises, and possibly more dynamic double-leg exercises for proprioception, such as body weight squats or bosu squats.
Again, this will depend largely on the mechanism of injury and associated ligaments that are most damaged, as as well general severity of injury, but this is a common progression in general for most ankle injuries.
As we progress to more advanced phases of rehabilitation, it’s important to place an emphasis on ankle joint stability. Furthermore, as rehab progresses and the deltoid ligament becomes fully healed, it becomes more safe to challenge the ankle joint in general.
This doesn’t mean only medial ankle stability, as the entire ankle will likely have weakened and experienced a reduced proprioceptive input over the course of recovery, so it’s important to think about both the medial ankle specifically, as well as the entire ankle and lower extremity more globally.
This is usually when the the rehabilitation exercises become more fun, as they are largely focused on dynamic and functional strength and mobility, which ultimately resembles more of a workout. Rehabilitiation exercises may involve (but are not limited to):
Static single-leg balance on uneven surfaces, such as a bosu ball or wobble board:
Dynamic strength and proprioception where, such as single leg squats, single-leg deadlifts, or dynamic lunges onto an uneven surface:
Advanced stability exercises which focus on jumping and landing technique to ensure reactive stability is improved:
*** There are many variations of ladder drills that work on ankle stability. You can ensure ankle stability in all directions by going both directions (outside like above, then back towards the inside).
*** Additionally, you can focus on “absorbing” the impact for a soft landing and holding the position, then progress to more of a bounding exercise whereby you are focusing both on stability and energy return.
In any case, it’s highly recommended to seek physical therapy when treating an ankle sprain, as the process will be much more efficient and any questions or concerns can be addressed in a timely manner.
Even an initial assessment with one or two follow-ups can go a long way on guiding you how to self-manage your medial ankle sprain and provide you with the confidence you need to successfully recover from injury.
Additionally, avoiding chronic ankle instability can really help prevent the occurrence of future medial ligament injuries, as well as any other type of ankle injury. For additional support, some people also like trying out ankle braces, but this has to be with the knowledge that they still need the appropriate support offered by strength and proprioception.
In the mean time, we hope this article has proven useful in shedding light into the physiology, mechanism of injury, and what to expect with treatment for a medial ankle sprain.
Medial ankle sprains are far less common than lateral ankle sprains, but they do occur, and therefore should not be completely ignored.
The deltoid ligament complex largely comprises the medial ankle ligaments, and understanding the general structure and function of these ligaments can allow for informed decisions when it comes to subsequent care.
Physical therapy is typically recommended for ankle sprains, both of the medial and lateral variety, as this will allow for efficient care of the acute injury, as well as reduced risk of future injury.
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Golanó, P., Vega, J., de Leeuw, P.A.J. et al. Anatomy of the ankle ligaments: a pictorial essay. Knee Surg Sports Traumatol Arthrosc 18, 557–569 (2010). https://doi.org/10.1007/s00167-010-1100-x
Gregersen MG, Fagerhaug Dalen A, Nilsen F, Molund M. The Anatomy and Function of the Individual Bands of the Deltoid Ligament—and Implications for Stability Assessment of SER Ankle Fractures. Foot & Ankle Orthopaedics. 2022;7(2). doi:10.1177/24730114221104078
Won HJ, Won HS, Oh CS, Han SH, Chung IH, Suh JS, Lee WC. Posterior tibiotalar ligament: an anatomic study correlated with MRI. Clin Anat. 2014 Jul;27(5):798-803. doi: 10.1002/ca.22302. Epub 2013 Aug 30. PMID: 24038173.
The content here is designed for information & education purposes only and is not intended for medical advice.