Yim Physio Near Me: Flat Feet: short overview by sports physiotherapist.

Flat feet
(Ref: https://www.fixflatfeet.com/)

Flat foot is a common postural deformity that we have seen flat feet ordinary. We have thought flatfeet would always cause foot problems. This topic would be a bit deeper review of flat feet such as arch development, type of flat feet, and musculoskeletal disorders.

Prevalence of flat feet in children is inversely proportional with age. Higher prevalence (21% to 57%) has been reported among children of 2 to 6 years that the prevalence declines in primary school children (13.4% to 27.6%). While prevalence of flat feet in adults has been reported to be between 13.6% to 26.62%.

Type of flat feet

Flatfoot is characterized clinically by hindfoot valgus or eversion, forefoot supination in relation to the hindfoot, and a diminished or nonexistent medial longitudinal arch. Flat - feet that we have seen in normal life, however, the conditions can be divided into two types including rigid and flexible.

A rigid flat foot is characterized by a stiff, collapsed arch in both weight-bearing and non-weight-bearing positions. The differential diagnosis of Pediatric flat foot deformity consists of Rigid flatfoot with tarsal coalition, Rigid flatfoot without tarsal coalition, so - called peroneal spastic flatfoot, Inflammatory arthritic flatfoot, Neoplastic flatfoot.

Rigid flat feet that be flat both of non - weight and during weight bearing
(Ref: https://samantha153.wordpress.com/category/flat-feet/)

Whereas a flexible flat foot is characterized by a normal - appearing arch when the foot is not bearing weight but by a flattened arch when weight - bearing. Flexible flat feet are the most common type of flat foot. Harris and Beath have classified the flexible flat feet account for approximately 2/3 of all flat - foot occurrences.

A flexible flat foot results in hyperpronation, plantar flexion, adduction of the talus, and calcaneal eversion. If a flexible flat foot is neglected, it can worsen to become a rigid flat foot, resulting in a loss of flexibility, hindfoot eversion, and joint deformity with pain. From a biomechanical point of view, a flexible flat foot can cause some musculoskeletal problems because they require more energy consumption when performing movements such as walking, and running. The differential diagnosis of Pediatric flat foot deformity consists of Flexible flatfoot including Physiologic flexible flatfoot, Physiologic flexible flatfoot with short tendo - Achilles, Flexible flatfoot associated with accessory navicular, Paralytic (spastic and flaccid) flatfoot.

Soft flat feet that have arch with non - weight (above) and no arch with weight (below)
(Ref: https://www.semanticscholar.org/paper/Clinical-examination-of-the-foot-and-ankle.-Young-Niedfeldt/29bf0a47859ba614110d2e17270f54d503930fcf)

Evolution of foot arch

We have seen that every baby does not have a foot arch, maybe, because the baby's age is not about time to stand and walk. Standing, walking, running, or jumping have to be supported by feet that human feet have important roles in supporting, moving and balancing the body. The feet must not only support the weight of the body but must also have the elasticity to absorb the burden associated with supporting an excessive body weight. Foot elasticity is a function of the arched shape of the foot and the associated bone, ligament, tendon, and muscle structures, which form what is called the foot arch.

The medial longitudinal arch typically starts to develop around the age of 2 years with development continuing until age 6 - 10 years, at which point approximately 20 - 25% of individuals remain flatfooted. Most children’s feet are, and remain, pain free whether or not they develop a longitudinal arch. Some young children with physiologic flatfeet present with bilateral non- localized activity - related and/or nocturnal foot and/or leg pain without any findings of redness, swelling, tenderness, or warmth. Early fatigue and rapid shoe breakdown may be reported.

Baby feet
(Ref: https://www.bioped.com/)

In 90% of the children aged older than 2 years, an anatomic variation resembling flatfoot can be seen which is due to infantile adipose cushion formation localized on the medial part of the foot. Besides, toddlers who start to walk can assume a flatfoot posture. In fact they try to walk with their feet resting entirely on the ground so as to maintain a balanced posture. Consequently, they shift their weight-bearing axis to the first or second tarsometatarsal joint which may induce a flatfoot posture. In most of the children normal longitudinal arch develops at 3 - 5 years of age, and in only 4% of them flatfoot persists after 10 years of age.

Child feet
(Ref: https://www.doreenfac.com.au/)

In nearly 23% of the adult population collapse of the medial longitudinal arch of the foot can be seen. However it is not an isolated entity, and in 2/3 of the cases, subtalar complex, hyperflexible ankle joint, and in one-fourths contracture of the triceps surae muscle have been observed. Probably these combined pathologies cause patients’ complaints rather than collapse of the medial longitudinal arch.

Prevalence of flat feet varies with age, type of population and the presence of comorbidities. Flat feet have been associated with family history, wearing footwear during childhood, urban residence obesity, age, gender, BMI, and foot length. Flat feet could also be secondary to various conditions, such as ligament laxity, Rheumatoid arthritis, Diabetes, foot or ankle injury, posttraumatic arthritis, peroneal spastic flat foot, Charcot foot and posterior tibial tendon dysfunction. These factors can develop flat feet change in adults and elders, especially in high BMI groups.

Overweight feet
(Ref: https://policyinpractice.co.uk/)

Pathoanatomy/Biomechanics of Flatfoot Deformity

the subtalar joint complex (STJC), recognizing that the talo-calcaneal joint (the true subtalar joint) is the most important joint, and the location of all major foot deformities that can only move in combination with the talo-navicular joint.

The axis of motion of the STJC is a constrained ball and socket-type joint that rotates three-dimensionally around a fixed oblique axis. Imagery between subtalar joint and hip joint, in the hip, the femoral head rotates within the acetabulum. In the subtalar joint, the acetabulum pedis (socket), which comprises the navicular, the anterior and middle articular facets of the calcaneus, and the spring ligament, rotates around the talar head (ball).

Subtalar joint complex (Blue line) (Ref: https://ankleandfootcentre.com.au/)

More recently, the concept of the acetabulum pedis (AP) has been expanded to develop that of the calcaneopedal unit (CPU), which is a term used to describe the entire foot including that beyond the acetabulum pedis or subtalar joint complex. All major foot deformities, including flatfoot, have rotationally opposite static deformities within the CPU in relationship to the subtalar joint deformity. In flat feet, the hindfoot assumes a valgus position with eversion of the STJC, or more accurately, external rotation, dorsiflexion, and pronation of the AP/CPU around the talus. In flatfoot, the rotationally opposite direction deformity within the CPU is supination. These rotationally opposite direction deformities enable a flatfoot to maintain a plantar-grade tripod configuration. Valgus/eversion (pronation) of the hindfoot with rotationally opposite direction supination of the forefoot enable weightbearing on the plantar-medial corner of the calcaneus and the first and fifth metatarsal heads.

The hindfoot assumes a valgus position with eversion of the STJC in flat feet (Left). Contrast with high arch shows a varus position (Right) (Ref: https://www.pinterest.com/)

Among those structures, the medial longitudinal arch (MLA) of the human foot has multiple functions, including absorbing and distributing load forces and providing stability. However, if the MLA structure collapses, which may be due to various causes such as posterior tibial tendon dysfunction or tight gastrocnemius soleus complex, a flat-foot condition occurs. In flat - foot cases, downward forces are deflected toward the inside of the foot, including the forefoot and the medial column, due to excessive pronation (hyperpronation).

Medial longitudinal arch (Upper), Lateral longitudinal arch (middle), Transverse arch (lower)
(Ref: https://epos.myesr.org/)

The 3 lesion levels of flat feet pathophysiology are the talonavicular, tibiotarsal and midfoot joints. The subtalar joint is damaged by the consequent rotational defects. Clinical examination determines deformity and reducibility, and assesses any posterior tibialis muscle deficit, the posterior tibialis tendon and spring ligament being frequently subject to degenerative lesions.

Flat feet clinical presentation

Many people with flat feet are asymptomatic or never have trouble. By theory, however, the deformities concomitant with flat feet may cause pain, instability, uneven plantar pressure distribution, gait problems and foot fatigue which may have a significant influence on daily activities. All these changes can subsequently lead to slower walking speed, decreased stride length and cadence and increased stance duration all of which reduces functionality and overall well - being. The features of flat feet are an extremely low arch that increases the risk of hallux valgus, hammer toes, patellofemoral pain, and other musculoskeletal complications including low back pain.

Flatfoot is considered pathological only when symptomatic. Pain is generally located in

the medial part of the hindfoot, along the posterior tibial tendon, sometimes associated with effusion into the tendon sheath. Pain may be plantar and deep, suggesting spring ligament lesion. Even so, such pain may be caused by another pathology, such as talocalcaneal synostosis coalition or talonavicular, subtalar or mediotarsal osteoarthritis. Pain may also be lateral, due to fibulocalcaneal impingement in severe tibiotalar valgus, calcaneocuboid impingement in severe forefoot abduction, or impingement between the lateral tubercle of the talus and dorsal angle of Gissane of the anterior apophysis of the calcaneus in case of rotation and slippage of the talus.

The posterior tibialis tendon and spring ligament (Ref: https://coa.org/2017/presentations/Sunday/8SitlerDavidUpdate2.pdf)

Fundamental of flat feet treatment

3 majors treatment of flat feet consists of operative, insole, and exercises. The golden period of children must be before 6 years old and not greater than 10 years old. In physiotherapy, we have always suggested arch support insoles and exercise that focus on exercises.

Flatfoot exercises are analyzed in two main headings: weight - bearing, and non - weight - bearing exercises Exercises performed while seated are non - weight - bearing exercises which include rotating the feet, trying to grip the objects on the floor with foot, holding knees, and feet in extension, forcing the toes for abduction, and adduction, and crossing one foot over the other. Similarly, walking on tiptoes or on the outside edge of the foot, standing on tiptoes on an elevated surface, and walking with flexed feet are some of the weight - bearing exercises. If contracture of the Achilles tendon is present, stretching exercises, and Thera - Band exercises should be performed by the parents or if compliant by the patients themselves.