Foot and Ankle Anatomy
The feet are often the point of connection between our human body and the earth. Gravity pulls the body down as the soles of the feet touch the ground, and through our physical support matrix made up by the skeleton, muscles, nerves, and connective tissue (to mention some categories of the physical human body), we push down into the earth in order to stand upright. The feet give us integrity in the posture. The feet and ankles play a crucial role in our posture and overall physical well-being.
Ankle and Foot anatomy
The foot is a complex structure composed of 26 bones, 33 joints, and more than 100 muscles, tendons, and ligaments (Frontera et al., 2015). The shape of our feet is due to the arrangement of the 26 bones and their ligaments, as well as the surrounding muscles and fascia. No one foot is alike, not even your left and right foot.
The ankle joint is formed by the tibia, fibula, and talus bone and is responsible for supporting the weight of the body while allowing for movement and flexibility. It is, in fact, named the talo-crural joint (crural meaning leg), as the fibula and tibia bones compose a mortise for the talus bone (see figure below).
Range of motion
Understanding the normal ranges of movement of the foot and ankle is important in maintaining proper posture and preventing injury.
For simplicity one can view the ankle as a hinge joint, with one empirical axis and two movements - flexion and extension, or dorsiflexion and plantarflexion. Dors means back, implying back flexion, or an upward lifting of the foot, while plantar refers to the sole of the foot, flexing the foot toward the sole, or downward. There is a little wiggle room, and more if the ankle has been damaged or the ligaments ruptured. Overall range of motion includes 10 to 20° of dorsiflexion through to 40–55° of plantarflexion.
The foot has another type of movement; supination and pronation. Supination is the action of lifting the sole of the foot in and up toward the midline, while pronation is the opposite - lifting or tilting the sole out from the midline. The range of motion of pronation is 0-30´while it is 0-60´for supination.
Supporting structures
The foot and ankle are complex structures that require a multitude of supporting tissues to function properly. Ligaments are the primary connective tissues responsible for stabilizing the foot and ankle joints. They are tough bands of fibrous tissue that connect bone to bone and provide structural support. Some of the main ligaments in the foot and ankle include the deltoid ligament, the lateral collateral ligament, and the anterior talofibular ligament. Fascia is another important supporting structure in the foot and ankle. It is a thin layer of connective tissue that covers and connects muscles and bones. In the foot and ankle, the plantar fascia plays an important shock absorbing role, as well as it contributes in maintaining the arch of the foot. Together, the ligaments and fascia work in concert to provide stability and support to the foot and ankle complex.
The arches
The arches of the foot are a critical component of the foot's structure, providing stability and support during movement. There are three primary arches in the foot: the medial longitudinal arch, the lateral longitudinal arch, and the transverse arch. The medial longitudinal arch is the highest and most prominent of the arches, running from the heel to the ball of the foot. It is maintained by a combination of ligaments, tendons, and muscles, including the plantar fascia, which acts as a supportive sling. The lateral longitudinal arch runs parallel to the medial arch on the outer side of the foot and is primarily supported by the peroneus longus muscle. The transverse arch runs across the foot's midsection and is formed by the shape of the tarsal bones. The arches of the foot act like springs, absorbing shock and distributing weight during movement. A well-maintained arch is essential for proper foot function and can help prevent injuries such as plantar fasciitis and flat feet.
Injuries ankle/ foot
Yoga can be a beneficial practice for the feet and ankles, but it can also lead to injuries if not practiced mindfully. Unfortunately, injuries in yoga often occur through repetitive and incorrect alignment and technique over time, rather than due to high-force trauma. Therefore, it is important to train with an experienced yoga practitioner and to practice non-violence. We aim to avoid painful postures, especially those that cause pain in and around joints, which is common in the foot. Ankle sprains can occur when the ligaments supporting the ankle are stretched or torn, often due to misalignment over time or excessive force on the joint, such as coming out of a handstand without control. The fibula bone's hard end point against the talus in the ankle typically provides more stability for pronation, which explains why pronation injuries and medial ligament ruptures are rare. In contrast, supination trauma toward the ankle can result in rupture or fractures of the lateral (outside) structures. Additionally, stress fractures can occur in the foot or ankle from overuse, repeated impact, or insufficient support. Certain foot and ankle imbalances or dysfunctions can lead to postural issues and chronic pain. For instance, overpronation or excessive inward rolling of the foot can cause misalignment of the entire lower body, leading to issues such as knee pain or lower back pain (Bramble et al., 2004). Practicing poses that focus on strengthening the muscles of the feet and ankles, such as standing on one leg or transitioning from high plank through chaturanga and to upward facing dog, while engaging the feet, can help improve overall posture and prevent issues caused by imbalances or dysfunctions.
To prevent these injuries, it is essential to practice yoga with proper alignment and form, and to use supportive props when necessary. Seeking medical attention is also crucial if an injury occurs.
Application to the yoga practice
When it comes to yoga and posture, the feet and ankles serve as the foundation for the entire practice. Proper alignment and engagement of the feet and ankles can help prevent injury, improve balance, and enhance overall posture. For example, practicing standing poses like Warrior I or II requires grounding down through the feet and evenly distributing weight between both feet to maintain stability and balance.
Warrior two
One of the best exercises for foot stability, or grounding, is the flow between warrior three and standing leg raise pose C, or in sanskrit, Utthita Eka Padasana, changing between the two postures a few times, focusing on grounding through the standing foot as the center of gravity changes.
Also experimenting with the feet and spreading the toes is good exercise - maybe combined with gentle massage of the plantar fascia. One tip is to pronate the foot in order to spread out the toes fully, and then supinating gently for stability after.
Feet, Posture and Science
A good posture starts with the feet because they are the foundation of the body. Faults in the feet can lead to issues in other parts of the body, such as back pain, knee pain, and even headaches. When the feet are not properly aligned, it can cause imbalances in the body that can lead to tension and discomfort. By developing awareness of the feet and working on proper alignment and strengthening of the muscles, we can improve our overall posture and prevent these issues from arising. Some small studies have shown that bad posture might be related to osteoporosis, fractures, chronic pain and early death (Ensrud et al 1997; Kado et al 2009). Yoga has been investigated as a tool to improve your posture. In 2009 Greendale et al found that yoga gave a significant improvement in the level of kyphosis among elderly. Moreover, it turns out that a powerful posture alters your hormone levels, with greater performance at job interviews as a result Cuddy (2012).
The upright standing signature
As small babies, when we learn to stand upright for the first time, and from that moment on, we get our own unique standing trait, I call it the upright standing signature. This posture is made up of a certain technique, unique for your character, and involves everything from how we stack each bone on top of the other, starting from the foot’s sole. The bare foot is in connection with the ground in various degrees and shapes, and this affects the rest of the posture, the center of gravity, and your general and specific muscular tone. The connection is key.
Our upright standing signature can affect our body in many ways.
Balance and hence safety, including real protection from falling, but also a comforting sense or feeling of safety - a stable ground.
Tensions and pain. The posture affects everything from pelvic floor dysfunction, tension headaches, and lower back pain.
Breathing habits.
All of the above are causes of our greatest public health threats in modern society. Movement therapy might be one of the best investments in health.
The posture - a journey
Our upright standing signature is often inherited from our caregivers. Toddlers tend to mimic posture, and is an important feature for motoric development (PMID: 16763035). With time they develop both strength, flexibility, and balance - all important for a good posture. The best posture is not necessarily a straight, aligned posture. It is dynamic. It is dependent on the activation of new muscles. It implies balance.
Yoga is one tool that can contribute to increased awareness, and in turn improved posture. Among other benefits, the asana practice involves stretching, strengthening, technique and increasing your awareness.
If you want to practice and explore your own anatomy, join our foot and ankle anatomy course online.
Best wishes,
Tiril
