The bones of children are very malleable in infancy. This will generally mean that, despite the presence of a coalition, the bones can deform enough to allow painless walking until the child's skeleton has matured enough. 'Skeletal maturing' means that bone is laid down in the tissue that forms the immature bone shape gradually until adult bone is achieved at about the age of seventeen years in the feet. Other body parts reach skeletal maturity at different times. The onset of symptoms related to a tarsal coalition usually occurs at about nine to seventeen years of age, with a peak incidence occurring at ten to fourteen years of age. Symptoms may start suddenly one day and persist, and can include pain (may be quite severe), lack of endurance for activity, fatigue, muscle spasms and cramps, an inability to rotate the foot, or antalgic gait.

Tarsal coalition (also known as peroneal spastic flatfoot, calcaneonavicular bar, talocalcaneal bar, tarsal synostosis, or tarsal dysostosis) is an abnormal connecting bridge of tissue between two normally-separate tarsal bones. The term 'coalition' means a coming together of two or more entities to merge into one mass. The tissue connecting the bones, often referred to as a "bar", may be composed of fibrous or osseous tissue. The two most common types of tarsal coalitions are calcaneo-navicular and talo-calcaneal, comprising 90% of all tarsal coalitions. There are other bone coalition combinations possible, but they are very rare. Symptoms tend to occur in the same location, regardless of the location of coalition: on the lateral foot, just anterior and below the lateral malleolus. This area is called the sinus tarsi.

These conditions nearly all present with an insidious onset of pain referred to the location of the bony damage. Some, notably Kienbock's disease of the wrist, may involve considerable swelling, and Legg-Calvé-Perthes disease of the hip causes the victim to limp. The spinal form, Scheuermann's disease, may cause bending, or kyphosis of the upper spine, giving a "hunch-back" appearance.

Chopart's fracture–dislocation is a dislocation of the mid-tarsal (talonavicular and calcaneocuboid) joints of the foot, often with associated fractures of the calcaneus, cuboid and navicular.

The most common symptom is pain over the heel area, especially when the heel is palpated or squeezed. Patients usually have a history of recent trauma to the area or fall from a height. Other symptoms include: inability to bear weight over the involved foot, limited mobility of the foot, and limping. Upon inspection, the examiner may notice swelling, redness, and hematomas. A hematoma extending to the sole of the foot is called "Mondor Sign", and is pathognomonic for calcaneal fracture. The heel may also become widened with associated edema due to displacement of lateral calcaneal border. Involvement of soft tissue (tendons, skin, etc.,) should be evaluated because soft tissue injury has been associated to serious complications (see below).

Chopart's fracture–dislocation is usually caused by falls from height, traffic collisions and twisting injuries to the foot as seen in basketball players.

Synostosis (plural: synostoses) is fusion of two bones. It can be normal in puberty, fusion of the epiphysis, or abnormal. When synostosis is abnormal it is a type of dysostosis.

Examples of synostoses include:

- craniosynostosis – an abnormal fusion of two or more cranial bones;

- radioulnar synostosis – the abnormal fusion of the radius and ulna bones of the forearm;

- tarsal coalition – a failure to separately form all seven bones of the tarsus (the hind part of the foot) resulting in an amalgamation of two bones; and

- syndactyly – the abnormal fusion of neighboring digits.

Synostosis within joints can cause ankylosis.

In humans, these conditions may be classified into three groups:

1. Spinal: Scheuermann's disease (of the interspinal joints) which is a curve in the thoracic spine.

2. Articular: Legg-Calvé-Perthes disease (or, avascular necrosis of the femoral head in the hip), Köhler's disease (of the tarsal navicular bone of the foot), Panner's disease (of the capitulum of the elbow), and Freiberg's infraction (of the second or third metatarsal of the foot and less frequently the first or fourth; sometimes called Freiberg's Infraction or Freiberg's disease)

3. Non-articular: This group includes Sever's disease (of the calcaneus, or heel), and Kienbock's disease of the hand, and other conditions not completely characteristic of the osteochondrosis, such as Osgood-Schlatter's disease (of the tibial tubercle) and Osteochondritis dissecans.

A calcaneal fracture is a break of the calcaneus (heel bone). Symptoms may include pain, bruising, trouble walking, and deformity of the heel. It may be associated with breaks of the hip or back.

It usually occurs when a person lands on their feet following a fall from a height or during a motor vehicle collision. Diagnosis is suspected based on symptoms and confirmed by X-rays or CT scaning.

If the bones remain normally aligned treatment may be by casting without weight bearing for around eights weeks. If the bones are not properly aligned surgery is generally required. Returning the bones to their normal position results in better outcomes. Surgery may be delayed a few days as long as the skin remained intact.

About 2% of all fractures are calcaneal fractures, however, they make up 60% of fractures of the mid foot bones. Undisplaced fractures may heal in around three months while more significant fractures can take two years. Difficulties such as arthritis and decreased range of motion of the foot may remain.

Studies have shown children and adolescents with flat feet are a common occurrence. The human arch develops in infancy and early childhood as part of normal muscle, tendon, ligament and bone growth . Flat arches in children usually become high arches as the child progresses through adolescence and into adulthood. Since children are unlikely to suspect or identify flat feet on their own, it is important for adult caregivers to check on this themselves. Besides visual inspection, caregivers should notice when a child's gait is abnormal. Children who complain about calf muscle pains, arch pain, or any other pains around the foot area may be developing or have developed flat feet. Children with flat feet are at a higher risk of developing knee, hip, and back pain. A recent randomized controlled trial found no evidence for the efficacy of treatment of flat feet in children either from expensive prescribed orthotics i.e (shoe inserts) or less expensive over-the-counter orthotics. As a symptom itself, flat feet usually accompany genetic musculoskeletal conditions such as dyspraxia, ligamentous laxity or hypermobility.

Flat feet (also called pes planus or fallen arches) is a postural deformity in which the arches of the foot collapse, with the entire sole of the foot coming into complete or near-complete contact with the ground. Some individuals (an estimated 20–30% of the general population) have an arch that simply never develops in one foot (unilaterally) or both feet (bilaterally).

There is a functional relationship between the structure of the arch of the foot and the biomechanics of the lower leg. The arch provides an elastic, springy connection between the forefoot and the hind foot. This association safeguards so that a majority of the forces incurred during weight bearing of the foot can be dissipated before the force reaches the long bones of the leg and thigh.

In pes planus, the head of the talus bone is displaced medially and distal from the navicular. As a result, the Plantar calcaneonavicular ligament (spring ligament) and the tendon of the tibialis posterior muscle are stretched, so much so that the individual with pes planus loses the function of the medial longitudinal arch (MLA). If the MLA is absent or nonfunctional in both the seated and standing positions, the individual has “rigid” flatfoot. If the MLA is present and functional while the individual is sitting or standing up on their toes, but this arch disappears when assuming a foot-flat stance, the individual has “supple” flatfoot. This latter condition can be correctable with well-fitting arch supports.

Three studies (see citations below in military section) of military recruits have shown no evidence of later increased injury, or foot problems, due to flat feet, in a population of people who reach military service age without prior foot problems. However, these studies cannot be used to judge possible future damage from this condition when diagnosed at younger ages. They also cannot be applied to persons whose flat feet are associated with foot symptoms, or certain symptoms in other parts of the body (such as the leg or back) possibly referable to the foot.

Radioulnar synostosis is one of the more common failures of separation of parts of the upper limb. There are two general types: one is characterized by fusion of the radius and ulna at their proximal borders and the other is fused distal to the proximal radial epiphysis. Most cases are sporadic, congenital (due to a defect in longitudinal segmentation at the 7th week of development) and less often post-traumatic, bilateral in 60%, and more common in males. Familial cases in association with autosomal dominant transmission appear to be concentrated in certain geographic regions, such as Sicily.

The condition frequently is not noted until late childhood, as function may be normal, especially in unilateral cases. Increased wrist motion may compensate for the absent forearm motion. It has been suggested that individuals whose forearms are fixed in greater amounts of pronation (over 60 degrees) face more problems with function than those with around 20 degrees of fixation. Pain is generally not a problem, unless radial head dislocation should occur.

Most examples of radioulnar synostosis are isolated (non-syndromic). Syndromes that may be accompanied by radioulnar synostosis include X chromosome polyploidy (e.g., XXXY) and other chromosome disorders (e.g., 4p- syndrome, Williams syndrome), acrofacial dysostosis, Antley–Bixler syndrome, genitopatellar syndrome, Greig cephalopolysyndactyly syndrome, hereditary multiple osteochondromas (hereditary multiple exostoses), limb-body wall complex, and Nievergelt syndrome.

Craniosynostosis (from cranio, cranium; + syn, together; + ostosis relating to bone) is a condition in which one or more of the fibrous sutures in an infant skull prematurely fuses by turning into bone (ossification). Craniosynostosis has following kinds: scaphocephaly, trigonocephaly, plagiocephaly, anterior plagiocephaly, posterior plagiocephaly, brachycephaly, oxycephaly, pansynostosis.

Curb is defined in older literature as enlargement secondary to inflammation and thickening of the long plantar ligament in horses. However, with the widespread use of diagnostic ultrasonography in equine medicine, curb has been redefined as a collection of soft tissue injuries of the distal plantar hock region. Curb is a useful descriptive term when describing swelling in this area.

Lisfranc injury, also known as Lisfranc fracture, is an injury of the foot in which one or more of the metatarsal bones are displaced from the tarsus. The injury is named after Jacques Lisfranc de St. Martin (2 April 179013 May 1847), a French surgeon and gynecologist who described an amputation of the foot through the tarsometatarsal articulation, in 1815, after the War of the Sixth Coalition.

When plantar fasciitis occurs, the pain is typically sharp and usually unilateral (70% of cases). Heel pain is worsened by bearing weight on the heel after long periods of rest. Individuals with plantar fasciitis often report their symptoms are most intense during their first steps after getting out of bed or after prolonged periods of sitting. Improvement of symptoms is usually seen with continued walking. Rare, but reported symptoms include numbness, tingling, swelling, or radiating pain. Typically there are no fevers or night sweats.

If the plantar fascia continues to be overused in the setting of plantar fasciitis, the plantar fascia can rupture. Typical signs and symptoms of plantar fascia rupture include a clicking or snapping sound, significant local swelling, and acute pain in the sole of the foot.

Camptodactyly is a medical condition that causes one or more fingers to be permanently bent. It involves fixed flexion deformity of the proximal interphalangeal joints. The fifth finger is always affected.

Camptodactyly can be caused by a genetic disorder. In that case, it is an autosomal dominant trait that is known for its incomplete genetic expressivity. This means that when a person has the genes for it, the condition may appear in both hands, one, or neither. A linkage scan proposed that the chromosomal locus of camptodactyly was 3q11.2-q13.12.

The name is derived from the ancient Greek words "kamptos" ("bent") and "daktylos" ("finger").

Diplopodia is a congenital anomaly in tetrapods that involves duplication of elements of the foot on the hind limb. It comes from the Greek roots diplo = "double" and pod = "foot". Diplopodia is often found in conjunction with other structural abnormalities and can be lethal. It is more extreme than polydactyly, the presence of extra digits.

Plantar fasciitis is a disorder that results in pain in the heel and bottom of the foot. The pain is usually most severe with the first steps of the day or following a period of rest. Pain is also frequently brought on by bending the foot and toes up towards the shin and may be worsened by a tight Achilles tendon. The condition typically comes on slowly. In about a third of people both legs are affected.

The causes of plantar fasciitis are not entirely clear. Risk factors include overuse such as from long periods of standing, an increase in exercise, and obesity. It is also associated with inward rolling of the foot and a lifestyle that involves little exercise. While heel spurs are frequently found it is unclear if they have a role in causing the condition. Plantar fasciitis is a disorder of the insertion site of the ligament on the bone characterized by micro tears, breakdown of collagen, and scarring. As inflammation plays a lesser role, many feel the condition should be renamed plantar fasciosis. The diagnosis is typically based on signs and symptoms with ultrasound sometimes used to help. Other conditions with similar symptoms include osteoarthritis, ankylosing spondylitis, heel pad syndrome, and reactive arthritis.

Most cases of plantar fasciitis resolve with time and conservative methods of treatment. Usually for the first few weeks people are advised to rest, change their activities, take pain medications, and stretch. If this is not sufficient physiotherapy, orthotics, splinting, or steroid injections may be options. If other measures do not work extracorporeal shockwave therapy or surgery may be tried.

Between 4% and 7% of people have heel pain at any given time and about 80% of these cases are due to plantar fasciitis. Approximately 10% of people have the disorder at some point during their life. It becomes more common with age. It is unclear if one sex is more affected than the other.

Lameness is most commonly caused by pain, but may also be the result of neuromuscular disease or mechanical restriction. Lameness itself is a clinical sign, and not a diagnosis.

In humans, the midfoot consists of five bones that form the arches of the foot (the cuboid, navicular, and three cuneiform bones) and their articulations with the bases of the five metatarsal bones. Lisfranc injuries are caused when excessive kinetic energy is applied either directly or indirectly to the midfoot and are often seen in traffic collisions or industrial accidents.

Direct Lisfranc injuries are usually caused by a crush injury, such as a heavy object falling onto the midfoot, or the foot being run over by a car or truck, or someone landing on the foot after a fall from a significant height. Indirect Lisfranc injuries are caused by a sudden rotational force on a plantar flexed (downward pointing) forefoot. Examples of this type of trauma include a rider falling from a horse but the foot remaining trapped in the stirrup, or a person falling forward after stepping into a storm drain.

In athletic trauma, Lisfranc injuries occur commonly in activities such as windsurfing, kitesurfing, wakeboarding, or snowboarding (where appliance bindings pass directly over the metatarsals). American football players occasionally acquire this injury, and it most often occurs when the athlete's foot is plantar flexed and another player lands on the heel. This can also be seen in pivoting athletic positions such as a baseball catcher or a ballerina spinning.

Besides swelling in the long plantar ligament, injury to the deep digital flexor tendon, superficial digital flexor tendon, tarsocrural lateral collateral ligament or peritendonous/periligamentous tissues in this region can contribute to the appearance of curb. Sickle-hocked conformation is a predisposing risk factor for the development of curb. (See hind leg conformation)

Fluid accumulation and/or swelling are almost always found in the peritendonous/periligamentous tissues in curb, often with no additional underlying injuries.

Injury to the superficial digital flexor tendon as a cause of curb is as common as injury to the long plantar ligament. Injury to the deep digital flexor tendon as a cause of curb is less common, and collateral ligament desmitis in the tarsocrural joint is uncommon. Combination of injury to the long plantar ligament and tendon of the gastrocnemius is also seen.

Various horseman’s terms have evolved over the years to describe common lamenesses or blemishes (defects that do not cause lameness) in horses.

- Bog spavin: excessive synovial fluid in the tarsocrural joint, which leads to a large, soft, cool distention on the dorsal surface of the hock.

- Bone spavin: osteoarthritis of the distal hock joints, which produces lameness and is sometimes seen as a visible, hard swelling on the inside of the hock joint.

- Bowed tendon: tendinitis of the superficial or deep digital flexor tendons, which leads to a "bowed" appearance when the tendon is seen in profile. Considered a lameness when acute, and a blemish once healed, although the tendon is at greater risk for re-injury.

- Bucked shins: pain, heat, and swelling over the dorsal surface of the cannon bone most commonly seen in racehorses. This complex disease process, called "dorsal metacarpal disease," involves inflammation of the periosteum, subperiosteal hematoma, and microfractures to the cortex of the underlying bone.

- Capped joint: Inflammation leading to the development of a "false" or acquired bursa over the point of the elbow (capped elbow, also known as a "shoe boil"), point of the hock (capped hock), or knee (capped knee, or carpal hygroma) which causes an obvious swelling in the area. These are generally considered blemishes.

- Curb: a thickening or bowing on the caudal surface of the calcaneous. Classically associated with damage to the long plantar tarsal ligament of the hock, it is actually most commonly due to injury to the superficial digital flexor tendon, but may also involve the deep digital flexor tendon, or the surrounding soft tissue structures.

- Founder (laminitis): a very painful condition resulting from the inflammation of the laminae within the hoof, leading to rotation of the coffin bone.

- Navicular disease or navicular syndrome: a catch-all phrase used to describe pain in the palmar hoof which was originally attributed to damage to the navicular bone. MRI has since shown that navicular syndrome may be caused by damage to any of the structures within the hoof, including the navicular bone, the navicular bursa, the coffin joint, the deep digital flexor tendon, and various ligamentous supportive structures.

- Osselets: swelling on the front surface of the fetlock joints of the front legs, caused by traumatic arthritis of the fetlock joints.

- Ringbone: boney proliferation around the pastern. May be articular (osteoarthritis) or non-articular. The articular forms can affect the pastern or coffin joints, and can cause lameness.

- Shoe boil: see "capped joint"

- Sidebone: ossification of the collateral cartilages of the hoof secondary to chronic concussion, may be palpated on just above the coronary band on either side of the hoof. Rarely causes lameness, therefore considered a blemish.

- Splints: bony enlargements in the area of the splint bone, most commonly on the inside of the front leg, but sometimes on the outside of the front leg or on a hind leg. They are caused by trauma to the split bone itself or the ligament between the splint bone and cannon bone. Acutely, there may be no visible swelling but the horse will be painful on palpation, and lame. Once healed, the boney swelling is cool to the touch and considered a blemish.

- Stocking up: Edema (fluid) retained in the lower legs due to reduced lymphatic drainage, often because the horse is sedentary for long periods (such as when stalled) but occasionally due to pathology. It is cool to the touch, and usually decreases or resolves with exercise. It is considered a blemish.

- Sweeney (shoulder sweeny): a loss of muscle of the shoulder. It is due to atrophy of the supraspinatous and infraspinatus muscles, secondary to damage to the suprascapular nerve, which innervates these muscles. It is usually caused by trauma, and is relatively rare in present day.

- Thoroughpin: effusion in the deep digital flexor tendon sheath, producing a small fluid swelling in the depression just front of the calcaneous. It is proximal to the tarsocrural joint, which helps distinguish it from bog spavin.

- Windpuffs (wind galls): cool, soft effusions in the area of the fetlock joint. May be "articular windgalls," which are the result of excessive synovial fluid in the fetlock joint capsule and located on the inside and outside of the fetlock, just behind the bones of the joint. Swelling towards the back of the joint are "tendonous windgalls," and are the result of effusion in the deep digital flexor tendon sheath. Windgalls are considered blemishes.

Some of the symptoms are:

- Pain and tingling in and around ankles and sometimes the toes

- Swelling of the feet

- Painful burning, tingling, or numb sensations in the lower legs. Pain worsens and spreads after standing for long periods; pain is worse with activity and is relieved by rest.

- Electric shock sensations

- Pain radiating up into the leg, and down into the arch, heel, and toes

- Hot and cold sensations in the feet

- A feeling as though the feet do not have enough padding

- Pain while operating automobiles

- Pain along the Posterior Tibial nerve path

- Burning sensation on the bottom of foot that radiates upward reaching the knee

- "Pins and needles"-type feeling and increased sensation on the feet

- A positive Tinel's sign

Tinel's sign is a tingling electric shock sensation that occurs when you tap over an affected nerve. The sensation usually travels into the foot but can also travel up the inner leg as well.

Winchester syndrome is a rare congenital connective tissue disease described in 1969, of which the main characteristics are short stature, marked contractures of joints, opacities in the cornea, coarse facial features, dissolution of the carpal and tarsal bones (in the hands and feet, respectively), and osteoporosis. Winchester syndrome was once considered to be related to a similar condition, multicentric osteolysis, nodulosis, and arthropathy (MONA). However, it was discovered that the two are caused by mutations found in different genes; they are now thought of as two separate disorders. Appearances resemble rheumatoid arthritis. Increased uronic acid is demonstrated in cultured fibroblasts from the skin and to a lesser degree in both parents. Despite initial tests not showing increased mucopolysaccharide excretion, the disease was regarded as a mucopolysaccharidosis. Winchester syndrome is thought to be inherited as an autosomal recessive trait.