Understanding Ankle Joint Dorsiflexion: A Key to Optimal Mobility
Ankle joint dorsiflexion is one of the most talked-about aspects when it comes to joint mobility and achieving optimal movement patterns. Many factors can contribute to restricted mobility in our clients, such as tight soleus and gastrocnemius muscles, heel-toe drop in shoes, flat feet, or high arches. The multitude of potential causes can sometimes feel overwhelming.
This article will delve into crucial concepts regarding ankle joint mobility and address one often overlooked cause of restricted dorsiflexion – the anteriorly shifted talus.
Why is Ankle Joint Dorsiflexion Important?
Joint mobility, especially in the foot and ankle, is essential for proper loading and unloading of impact forces and transferring associated potential energy. When our joints move—specifically the ankle—there is a stretching (or potentiating) effect on the Achilles tendon and surrounding fascial structures. Imagine this as stretching a rubber band or pulling back a bowstring.
The stretching of a rubber band or bowstring represents stored potential energy that we release to propel our leg forward during walking. If joint mobility is restricted, there is less stored energy in the tendon; instead of smoothly recoiling our leg forward, we end up pulling it forward with each step. This inefficiency can lead to increased workload, accelerated musculo-tendinous fatigue, and heightened injury risk.
How Much Dorsiflexion Do We Need?
The required amount of dorsiflexion depends on the activity being performed. Are you focusing on ankle joint dorsiflexion for squatting or for walking?
When assessing a patient, I primarily focus on their ankle joint dorsiflexion during walking since this movement pattern occurs over 10,000 times a day. My philosophy is that if we cannot master the fundamental functional movement demands of walking, we shouldn’t progress to more challenging movement patterns.
In summary:
- Proper ankle joint dorsiflexion is crucial for efficient movement.
- Restricted mobility can lead to increased workload and risk of injury.
- Assessing for adequate dorsiflexion should prioritize common daily activities like walking before moving on to more complex movements.
By understanding these key concepts and addressing factors like an anteriorly shifted talus, we can significantly improve our clients’ overall mobility and reduce their risk of injury.
Understanding Ankle Joint Dorsiflexion Assessment for Walking
The Importance of Straight Leg Position
If you’re concerned about ankle joint dorsiflexion for walking, it’s crucial to perform the assessment in a straight leg position. This is because our ankle dorsiflexes in this manner during walking.
Common Misconceptions
Many videos and articles online demonstrate a knee-bent ankle joint assessment technique, as above picture. While not incorrect, this method doesn’t apply to walking.
Preferred Open Chain Assessment Method
For an accurate open chain assessment, have the client lie on their back. Then, place the subtalar joint (STJ) into a neutral position and maximally dorsiflex the ankle. Aim for at least 5 degrees of dorsiflexion in this position.
Follow-Up with Silverskiöld Test(1)
You can follow this assessment with a Silverskiöld test—where the client bends their knee to see if there’s increased range of motion due to a tight gastrocnemius muscle.
Why Neutral STJ and 5 Degrees of Dorsiflexion?
You might wonder why keeping the STJ neutral and having only 5 degrees of ankle dorsiflexion is sufficient for walking. Here’s why:
- Maximum Dorsiflexion During Gait: The peak need for ankle dorsiflexion occurs in late midstance when your leg is behind you and your heel is down.
- Stability During Push-Off: At this moment, we transition through our ankle towards becoming a supinated, stable rigid lever ready for push-off. Full pronation isn’t desired during this transition.
- Maintaining Foot Stability: Keeping the STJ neutral restricts excessive ankle dorsiflexion, helping maintain foot stability during ambulation.
Closed Chain Assessment: Gait Analysis
For closed chain assessment of ankle joint dorsiflexion, observe how a client moves through late midstance during gait analysis. This observation will indicate if they possess sufficient functional ankle joint dorsiflexion.
By understanding these principles and using appropriate assessment techniques, you can ensure that your evaluation of ankle joint dorsiflexion is both accurate and relevant to walking mechanics.
The Importance of 5 Degrees of Dorsiflexion in Walking
Your ankle and foot will naturally find the path of least resistance to move through late midstance. This can manifest in several ways:
- Turning your foot outward and adopting a “duck walk.”
- Pronation as you transition through late midstance.
- Lifting your heel prematurely, resulting in a bouncy gait.
In simpler terms, your body will compensate to get through late midstance in a less efficient manner, which stores less potential energy and increases the risk of soft tissue or joint injury.
This underscores the importance of not only assessing proper ankle joint dorsiflexion but also understanding its underlying causes and how to address them.
Increasing Ankle Joint Dorsiflexion
To effectively increase ankle joint dorsiflexion, it’s crucial to determine why the ankle is restricted in the first place.
Many professionals primarily consider soft tissue reasons for limited ankle dorsiflexion. These include:
- Tight soleus
- Tight gastrocnemius muscles (calves)
- Tight Achilles tendon
- Tight plantar fascia
However, the causes of ankle joint restriction extend beyond just soft tissue issues.
The Overlooked Cause: Bony Block
One often overlooked cause of limited ankle dorsiflexion is a bony block. This refers to physical impediments within the joint itself that prevent normal movement. Recognizing this can be vital in accurately diagnosing and effectively treating restricted dorsiflexion.
By identifying both soft tissue and bony causes of ankle restriction, you can develop a comprehensive approach to improving mobility and reducing injury risk.
What is a Bony Block?
A bony block at the ankle joint can occur for several reasons, with the most common being bone spurs (osteophytes) or an anteriorly shifted talus. For this article, we will focus on the anteriorly shifted talus.
The Talus
The talus is a fascinating bone that articulates with three joints:
- The ankle
- The subtalar joint
- The talonavicular joint
Unique in its structure, the talus does not have any muscle or tendon attachments, making it somewhat of a “floating” bone. This characteristic means that ligaments are solely responsible for keeping the talus in place within the ankle mortise.
Causes of Anterior Talus Shift
Several factors can lead to a decrease in stability of the talus bone, allowing it to shift within the ankle joint:
- Ankle sprains
- Extreme ankle plantarflexion (common in dancers)
- Ligament laxity
When these conditions occur, they can cause the talus to shift anteriorly. This anterior shift happens due to the shape of the talar dome and reduced posterior stability of the posterior ankle mortise.
Impact on Ankle Dorsiflexion
When the talus shifts anteriorly and you attempt to dorsiflex your ankle, the tibia collides with the talus. This results in limited dorsiflexion. Upon examination, this typically feels like a “hard stop” at the end range of motion. Clients often describe experiencing pain or tightness at the front (anterior) part of their ankle.
Understanding these dynamics can help in diagnosing and treating issues related to bony blocks effectively.
Instructions for Proper Foot Position and Band Placement
- Ensure Neutral Foot Position
- Elevate the Foot
- Correct Band Placement
Secure the band under the malleoli (the bony prominences on either side of your ankle). - Maintain Proper Angle of Pull
Ensure that the angle of pull is directed downwards and laterally. - Tibia Translation and STJ Alignment
Limit tibia translation to 45 degrees while keeping the subtalar joint (STJ) in a neutral position. - Daily Repetition if Needed
Repeat these steps every day before training, as this method is not a permanent fix but can help manage issues effectively.
Follow these guidelines consistently for best results in managing foot positioning and alignment during exercises or training sessions.
Stay #postivemovementexperience
Reference
1.Seung Jun Moon, et al. https://doi.org/10.3349/ymj.2017.58.6.1170
Image: Google courtesy
