Sole of the foot – structure, function & diseases
Sole of foot
Ever since man rose above apes and found the ability to walk upright, the human foot has had a high level of complexity and function. The foot consists of the tarsus, the five toes, the metatarsus and the sole of the foot located there .
On the latter are receptors that function as a sense of touch. Touch, pressure, pain or temperature are perceived particularly intensively there, even more than on the five toes. This is a tactile perception that is part of the sense of touch.
What is the sole of the foot?
The sole of the foot forms the entire underside of the foot. The bony base is formed by metatarsal bones. It has a surface sensitivity there that serves to protect the body.
This rapid perception of change and touch is made possible by the mechanoreceptors in the skin . Meissner, Vater-Pacini and Ruffini corpuscles and Merkel cells carry the information towards the central nervous system via nerve fibers . Because of the many nerve endings that reside in the soles of the feet, people often feel ticklish on their feet.
In turn, the pain and thermoreceptors are responsible for pain and temperature changes. They are mediated by class C afferents via the nerve endings. If there is a disorder or damage to these nerves, anesthesia or paresthesia occurs . In addition to the state of insensibility and the state of paraesthesia , there is also hypersensitivity, which can lead to painful sensations. This is then referred to as a tactile defense. The skin uses this defense to react to received stimuli.
Anatomy & Structure
In biology, the sole of the foot is divided into the heel, the outer edge of the foot, the area of the longitudinal arch and the ball of the foot. All of these areas can be seen in a footprint in the sand. Medical diagnoses can be made from the impression, for example whether someone has a flat foot or not. Ground contact is not normally made over the entire sole of the foot. In a healthy foot, the inner edge of the foot does not lie in the area of the longitudinal arch.The relief of the sole of the foot has a strong ball of the heel in the rear area, a ball of the foot with the ball of the small toe and the ball of the big toe in the front area. The concave arch of the foot lies between the soft tissue protrusions. The sole of the foot has a substructure that consists of fatty bodies, but is also so stable that people do not slip as soon as they move. These fat bodies absorb shock and have a cushioning effect. The muscles , the skeleton and other anatomical conditions cannot be felt through this cushion . The exception is the metatarsal heads of the rays in the middle.
Underneath the entire skin of the sole of the foot lies a fibrous sheet called the plantar fascia. The term “Planta” is the Latin term for the sole of the foot. Foot skeleton, muscles, skin and plantar fascia are connected by fibers and form a functional unit.
Function & Tasks
Shoe size used to be determined using a pedoscope. This was used to x-ray the foot in the shoes in shoe shops. In orthopedics, the foot is examined using a podoscope. This device can be used to diagnose foot damage, postural anomalies or general weaknesses.
A digital pedography can be used to document and display the pressure load, which both facilitates the diagnosis and enables the necessary therapy. As a result, load points and the human foot reaction forces are recorded dynamically and statically. The patient is placed on a glass platform that has a mirror and a scanning system so that a foot pressure analysis can be created. From the measurement results, therapies for correct movement sequences can be planned. In turn, the patient can use the mirror to visually check their own foot and adapt it to the specified movement pattern.
There are also special acupressure points on the sole of the foot that can be massaged. This form of therapy is one of the Eastern healing methods, which stimulates the self-healing of the body through a foot reflex zone massage, causes relaxation and promotes the entire blood circulation. The Eastern healing method is based on energy meridians in the foot, which can be stimulated and should lead to an energy boost. It also relieves pain or eliminates cramps. Acupressure is also said to help against bladder problems, loss of appetite or hemorrhoids .
Diseases
Since the feet are used almost constantly and are exposed to high loads, pain in the soles of the feet occurs more frequently. These can also lead to serious diseases or inflammation and require therapeutic help.The pain in the sole of the foot is rarely accompanied by injuries, but rather is expressed by a painful tingling in the foot or a flat pulling pain. There are also selective pressure pains that can occur and thus provide information about the cause of such complaints. Such can e.g. B. vascular diseases, fractures, torn ligaments or sprains .
Gout , rheumatic diseases, arthrosis or osteoporosis also lead to sole pain. The high pressure load leads to circulatory pain and affects the nerves and nerve endings. Complaints are caused by pinching off the nerve tracts in the section between the sole of the foot and the central nervous system. An emergency signal is sent to the brain, which is expressed by a strong pulling or tingling in the foot. Accompanying symptoms include low back pain or numbness in the legs.
Pressure pain on the heel bone, on the other hand, is usually an inflammation of the plantar fascia. The entire tendon plate of the foot is affected. The pain radiates to the metatarsophalangeal joints. The malposition of the feet also causes an unfavorable distribution of body weight and can lead to pain.
Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.