Calcaneus Health Dictionary

The heel is the hind part of the foot, formed by the CALCANEUS and the especially thick skin covering it. It is not subject to many diseases. Severe pain in the heel is sometimes a sign of gout or rheumatism.... heel

A thick tendon that joins the calf muscles to the heel bone (calcaneus) and pulls up that bone. The tendon is prone to rupture in middle-aged people playing vigorous sports such as squash or tennis. Named after the classical Greek hero Achilles, who was reputedly vulnerable to his enemies only in his heel.... achilles tendon

The large double muscle which forms the chief bulk of the calf, and ends below in the tendo calcaneus.... gastrocnemius

Also known colloquially as club-foot, this is a deformity apparent at birth, affecting the ankle and foot: the foot is twisted at the ankle-joint so that the sole does not rest on the ground when standing. The heel may be pulled up so that the individual walks on the toes (talipes equinus); the toes may be bent up and the heel used for walking (talipes calcaneus); the sole may be twisted inwards (varus) or outwards (valgus); or the individual may have a combination of deformities (equinovarus). The condition is probably the result of genetic predisposition with an environmental trigger. In the UK the incidence is one in 1,000 live births and talipes is more common in boys than in girls, with 10 per cent of sufferers having a ?rst-degree relative with the same condition. Clinically, there are two types of congenital talipes equinovarus (CTEV): a milder form – resolving CTEV – in which full correction to the normal position is relatively easily achieved; and a more severe type

– resistant CTEV – which is harder to correct; and the infant has reduced calf-muscle bulk and abnormally shaped bones.

Treatment should be started at birth with the foot corrected to an improved position and then maintained in plaster of Paris or strapping

– a procedure performed weekly or more often. If the deformity is not corrected by around six weeks of age, a decision has to be made about whether to carry out surgical correction. If a deformity persists to maturity, a triple arthrodosis – fusion of three affected joints – may be required.... talipes

Of or pertaining to the TARSUS of the foot and ankle – this comprises TALUS, calcaneus navicular, cuboid and three cuneiform bones – or eyelid (see EYE).... tarsal

The region of the instep with its seven bones, the chief of which are the TALUS supporting the leg-bones and the CALCANEUS or heel-bone, the others being the navicular, cuboid, and three cuneiform bones.... tarsus

A tendon – also known as sinew, or leader – is the cord of tissue that attaches the end of a muscle to the bone or other structure upon which the muscle acts when it contracts. Tendons are composed of bundles of white ?brous tissue arranged in a very dense manner, and are of great strength. Some are rounded, some ?attened bands, whilst others are very short – the muscle-?bres being attached almost directly to the bone. Most tendons are surrounded by sheaths lined with membrane similar to the SYNOVIAL MEMBRANE lining joint-cavities: in this sheath the tendon glides smoothly over surrounding parts. The ?bres of a tendon pass into the substance of the bone and blend with the ?bres composing it. One of the largest tendons in the body is the Achilles tendon, or tendo calcaneus, which attaches the muscle of the calf to the calcaneus or heel-bone.

Tendon injuries are one of the hazards of sports (see SPORTS MEDICINE). They usually result from indirect violence, or overuse, rather than direct violence.

Rupture usually results from the sudden application of an unbalanced load. Thus, complete rupture of the Achilles tendon is common in taking an awkward step backwards playing squash. There is sudden pain; the victim is often under the impression that he or she has received a blow. This is accompanied by loss of function, and a gap may be felt in the tendon.

Partial Rupture is also accompanied by pain, but there is no breach of continuity or complete loss of function. Treatment of a complete rupture usually means surgical repair followed by immobilisation of the tendon in plaster of Paris for six weeks. Partial rupture usually responds to physiotherapy and immobilisation, but healing is slow.... tendon

the outer bone of the *tarsus, which articulates with the fourth and fifth metatarsal bones in front and with the calcaneus (heel bone) behind.... cuboid bone

n. any rheumatic disease resulting in inflammation of *entheses. Ankylosing *spondylitis, *psoriatic arthritis, and *reactive arthritis are examples. In these conditions the Achilles tendon is commonly involved, with swelling at its insertion on the calcaneus. Calcification within the tendon insertion may be seen on X-ray in patients with longstanding enthesopathy.... enthesopathy

(policeman’s heel) inflammation of the point of attachment of the *fascia in the sole of the foot to the calcaneus (heel bone), causing pain and localized tenderness of the heel. Treatments include heel pads, anti-inflammatory medication, steroid injections, or surgery. The inflammation takes 6–12 months to subside.... plantar fasciitis

*apophysitis caused by pulling at the point of insertion of the Achilles tendon into the calcaneus (heel bone), causing heel pain. [J. W. Sever (20th century), US orthopaedic surgeon]... sever’s disease

(astragalus) n. the ankle bone. It forms part of the *tarsus, articulating with the tibia above, with the fibula to the lateral (outer) side, and with the calcaneus below.... talus

The framework upon which the rest of the body is built up. The bones are generally called the skeleton, though this term also includes the cartilages which join the ribs to the breastbone, protect the larynx, etc.

Structure of bone Bone is composed partly of ?brous tissue, partly of bone matrix comprising phosphate and carbonate of lime, intimately mixed together. The bones of a child are about two-thirds ?brous tissue, whilst those of the aged contain one-third; the toughness of the former and the brittleness of the latter are therefore evident.

The shafts of the limb bones are composed of dense bone, the bone being a hard tube surrounded by a membrane (the periosteum) and enclosing a fatty substance (the BONE MARROW); and of cancellous bone, which forms the short bones and the ends of long bones, in which a ?ne lace-work of bone ?lls up the whole interior, enclosing marrow in its meshes. The marrow of the smaller bones is of great importance. It is red in colour, and in it red blood corpuscles are formed. Even the densest bone is tunnelled by ?ne canals (Haversian canals) in which run small blood vessels, nerves and lymphatics, for the maintenance and repair of the bone. Around these Haversian canals the bone is arranged in circular plates called lamellae, the lamellae being separated from one another by clefts, known as lacunae, in which single bone-cells are contained. Even the lamellae are pierced by ?ne tubes known as canaliculi lodging processes of these cells. Each lamella is composed of very ?ne interlacing ?bres.

GROWTH OF BONES Bones grow in thickness from the ?brous tissue and lime salts laid down by cells in their substance. The long bones grow in length from a plate of cartilage (epiphyseal cartilage) which runs across the bone about 1·5 cm or more from its ends, and which on one surface is also constantly forming bone until the bone ceases to lengthen at about the age of 16 or 18. Epiphyseal injury in children may lead to diminished growth of the limb.

REPAIR OF BONE is e?ected by cells of microscopic size, some called osteoblasts, elaborating the materials brought by the blood and laying down strands of ?brous tissue, between which bone earth is later deposited; while other cells, known as osteoclasts, dissolve and break up dead or damaged bone. When a fracture has occurred, and the broken ends have been brought into contact, these are surrounded by a mass of blood at ?rst; this is partly absorbed and partly organised by these cells, ?rst into ?brous tissue and later into bone. The mass surrounding the fractured ends is called the callus, and for some months it forms a distinct thickening which is gradually smoothed away, leaving the bone as before the fracture. If the ends have not been brought accurately into contact, a permanent thickening results.

VARIETIES OF BONES Apart from the structural varieties, bones fall into four classes: (a) long bones like those of the limbs; (b) short bones composed of cancellous tissue, like those of the wrist and the ankle; (c) ?at bones like those of the skull; (d) irregular bones like those of the face or the vertebrae of the spinal column (backbone).

The skeleton consists of more than 200 bones. It is divided into an axial part, comprising the skull, the vertebral column, the ribs with their cartilages, and the breastbone; and an appendicular portion comprising the four limbs. The hyoid bone in the neck, together with the cartilages protecting the larynx and windpipe, may be described as the visceral skeleton.

AXIAL SKELETON The skull consists of the cranium, which has eight bones, viz. occipital, two parietal, two temporal, one frontal, ethmoid, and sphenoid; and of the face, which has 14 bones, viz. two maxillae or upper jaw-bones, one mandible or lower jaw-bone, two malar or cheek bones, two nasal, two lacrimal, two turbinal, two palate bones, and one vomer bone. (For further details, see SKULL.) The vertebral column consists of seven vertebrae in the cervical or neck region, 12 dorsal vertebrae, ?ve vertebrae in the lumbar or loin region, the sacrum or sacral bone (a mass formed of ?ve vertebrae fused together and forming the back part of the pelvis, which is closed at the sides by the haunch-bones), and ?nally the coccyx (four small vertebrae representing the tail of lower animals). The vertebral column has four curves: the ?rst forwards in the neck, the second backwards in the dorsal region, the third forwards in the loins, and the lowest, involving the sacrum and coccyx, backwards. These are associated with the erect attitude, develop after a child learns to walk, and have the e?ect of diminishing jars and shocks before these reach internal organs. This is aided still further by discs of cartilage placed between each pair of vertebrae. Each vertebra has a solid part, the body in front, and behind this a ring of bone, the series of rings one above another forming a bony canal up which runs the spinal cord to pass through an opening in the skull at the upper end of the canal and there join the brain. (For further details, see SPINAL COLUMN.) The ribs – 12 in number, on each side – are attached behind to the 12 dorsal vertebrae, while in front they end a few inches away from the breastbone, but are continued forwards by cartilages. Of these the upper seven reach the breastbone, these ribs being called true ribs; the next three are joined each to the cartilage above it, while the last two have their ends free and are called ?oating ribs. The breastbone, or sternum, is shaped something like a short sword, about 15 cm (6 inches) long, and rather over 2·5 cm (1 inch) wide.

APPENDICULAR SKELETON The upper limb consists of the shoulder region and three segments – the upper arm, the forearm, and the wrist with the hand, separated from each other by joints. In the shoulder lie the clavicle or collar-bone (which is immediately beneath the skin, and forms a prominent object on the front of the neck), and the scapula or shoulder-blade behind the chest. In the upper arm is a single bone, the humerus. In the forearm are two bones, the radius and ulna; the radius, in the movements of alternately turning the hand palm up and back up (called supination and pronation respectively), rotating around the ulna, which remains ?xed. In the carpus or wrist are eight small bones: the scaphoid, lunate, triquetral, pisiform, trapezium, trapezoid, capitate and hamate. In the hand proper are ?ve bones called metacarpals, upon which are set the four ?ngers, each containing the three bones known as phalanges, and the thumb with two phalanges.

The lower limb consists similarly of the region of the hip-bone and three segments – the thigh, the leg and the foot. The hip-bone is a large ?at bone made up of three – the ilium, the ischium and the pubis – fused together, and forms the side of the pelvis or basin which encloses some of the abdominal organs. The thigh contains the femur, and the leg contains two bones – the tibia and ?bula. In the tarsus are seven bones: the talus (which forms part of the ankle joint); the calcaneus or heel-bone; the navicular; the lateral, intermediate and medial cuneiforms; and the cuboid. These bones are so shaped as to form a distinct arch in the foot both from before back and from side to side. Finally, as in the hand, there are ?ve metatarsals and 14 phalanges, of which the great toe has two, the other toes three each.

Besides these named bones there are others sometimes found in sinews, called sesamoid bones, while the numbers of the regular bones may be increased by extra ribs or diminished by the fusion together of two or more bones.... bone

A rare condition of unknown cause in which the muscles at the lower end of the oesophagus and the sphincter (valve) between the oesophagus and the stomach fail to relax to let food into the stomach after swallowing. As a result, the lowest part of the oesophagus is narrowed and becomes blocked with food, while the part above widens. Symptoms include difficulty and pain with swallowing and pain in the lower chest and upper abdomen.

A barium swallow (a type of barium X-ray examination) and gastroscopy may be performed to investigate achalasia.

Oesophageal dilatation allows the oesophagus to be widened for long periods. Surgery to cut some of the muscles at the stomach entrance may be necessary. Achilles tendon The tendon that raises the heel. The Achilles tendon is formed from the calf muscles (gastrocnemius, soleus, and plantar muscles) and is attached to the calcaneus (heel-bone). Minor injuries to the Achilles tendon are common and can result in inflammation (tendinitis).

Violent stretching of the tendon can cause it to rupture; in such cases, surgical repair may be necessary.... achalasia

The foot has 2 vital functions: to support the weight of the body in standing or walking and to act as a lever to propel the body forwards.

The largest bone of the foot, the heelbone (see calcaneus), is jointed with the ankle bone (the talus). In front of the talus and calcaneus are the tarsal bones, which are jointed the 5 metatarsals. The phalanges are the bones of the toes; the big toe has 2 phalanges; all the other toes have 3.

Tendons passing around the ankle connect the muscles that act on the foot bones. The main blood vessels and nerves pass in front of and behind the inside of the ankle to supply the foot. The undersurface of the normal foot forms an arch supported by ligaments and muscles. Fascia (fibrous tissue) and fat form the sole of the foot, which is covered by a layer of tough skin.

Injuries to the foot commonly result in fracture of the metatarsals and phalanges. Congenital foot abnormalities are fairly common and include club-foot (see talipes), and claw-foot. A bunion is a common deformity in which a thickened bursa (fluid-filled pad) lies over the joint at the base of the big toe. Corns are small areas of thickened skin and are usually a result of tight-fitting shoes. Verrucas (see plantar warts) develop on the soles of the feet. Athlete’s foot is a fungal infection that mainly affects the skin in between the toes. Gout often affects the joint at the base of the big toe. An ingrowing toenail (see toenail, ingrowing) commonly occurs on the big toe and may result in inflammation and infection of the surrounding tissues (see paronychia). Foot-drop is the inability to raise the foot properly when walking and is the result of a nerve problem.... foot