the transfer of weight and the force required to push off the toes into the next step. This mechanical function will be discussed in more detail subsequently. There is also a relationship that exists between the plantar fascia, the Achilles tendon, and the gastrocnemius muscle of the lower leg, which will be explored in the treatment section of this course. With such a heavy burden being placed on such a relatively small structure in the foot, it is easy to see why the plantar fascia is a common site for dysfunction, inflammation, and pain.
Figure 1
Where is the plantar fascia? To gain practical knowledge of the location and texture of the plantar fascia, use the live model of your own feet. With bare feet, sit in a chair with your knees bent at a 90-degree angle with both feet on the floor. Cross the left leg over the right, resting the left outer ankle on the thigh of the right leg. You should be able to see the arch of the left foot and easily reach the sole of the foot. With your right thumb tip, press into the sole of the foot at the front and center of the heel, right in front of the mound of the heel. Dorsiflex the toes, and with your left hand, trace the plantar fascia from What does the plantar fascia do? The plantar fascia has many roles in the normal function of the foot, the most important being its integral part of the windlass mechanism. In 1954, John Hicks first coined the term “windlass mechanism,” which is derived from sailing terminology, to describe the role of the plantar fascia in the movement of the foot. Hicks originally described the foot and its ligaments as an arch-like triangular structure or truss. The calcaneus, midtarsal joint, and metatarsals (the medial longitudinal arch) formed the truss’s arch. The plantar fascia formed the tie-rod that ran from the calcaneus to the phalanges. Vertical forces from body weight travel downward via the tibia and tend to flatten the medial longitudinal arch. Furthermore, ground reaction forces travel upward on the calcaneus and the metatarsal heads, which can further attenuate the flattening effect because these forces fall both posterior and anterior to the tibia. (Physiopedia, 2018) How does the plantar fascia work? To understand the function of the plantar fascia, use your own feet again. Walk barefoot and slowly across a hard surface. Notice what part of your heel lands on the floor first. As you roll forward onto the ball of the foot and the big toe, notice how the depth of the arch of your foot increases. This is the windlass mechanism in action. Next, repeat the exercise while running, still barefoot, and feel how much force is required to push off with the big toe into the next step of your stride. The plantar fascia plays a major role in how much push off force your foot is able to generate.
where the right thumb is pressing in forward toward the ball of the foot. You should be able to easily feel the thickest part of the plantar fascia, or the plantar aponeurosis, with the toes flexed. You may even be able to see the tension created by the plantar aponeurosis on the underside of the foot when the toes are flexed. Repeat the exercise, moving the pressing thumb slightly to either side and tracing forward with the other hand again. This should give you a clear indication of the location and superficial nature of your plantar fascia. In simpler terms, it is what happens in the foot when it comes between the downward force of the weight of the body and the upward force of that weight hitting the ground. The windlass mechanism is what allows you to land on the heel, then carry through to push off with the ball of the foot and big toe as part of a normal stride. The primary function of the plantar fascia is to create tension that shortens the distance between the heel and big toe, acting as a pulley on the underside of the foot and allowing the small bones of the foot to articulate with one another as the shape of the foot changes with motion. The windlass mechanism helps to create the propulsion of your stride as you lift the heel and push off with the big toe. This action happens naturally when barefoot, as the foot has the ability to move without restrictions. It can be somewhat compromised when wearing shoes because the stiffness of shoes can limit the normal range of motion of the structures of the foot. Next, repeat both exercises while wearing shoes. For a more in-depth experiment, try the exercise while wearing running shoes or any other athletic shoes and again with any other pair of shoes that you wear often. Do you notice how much less the foot, and especially the big toe, can bend and go through their natural range of motion in shoes? This can lead to a chronic shortening of the plantar fascia, which can be a contributing factor in inflammation of the plantar fascia, or plantar fasciitis.
SECTION 2: WHAT IS PLANTAR FASCIITIS?
fascia is designed to absorb the high stresses and strains we place on our feet. But, sometimes, too much pressure damages or tears the tissues. The body’s natural response to injury is inflammation, which results in the heel pain and stiffness of plantar fasciitis” (Perri et al., 2022). The most common symptom of plantar fasciitis is pain in the front of
Plantar fasciitis is a condition that occurs when the plantar fascia becomes inflamed or torn, typically as a result of overuse or excessive strain. The American Academy of Orthopedic Surgeons states that “Plantar fasciitis occurs when the strong band of tissue that supports the arch of your foot becomes irritated and inflamed ... The plantar
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Book Code: MLA1225
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