Metatarsus

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Bone: Metatarsus
Skeleton of foot. Lateral aspect.
Gray's subject #64 272
MeSH A01.378.610.250.300.480

The metatarsus consists of the five long bones of the foot, which are numbered from the medial side (ossa metatarsalia I.-V.); each presents for examination a body and two extremities. These are analogous to the metacarpals of the hand.

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[edit] Common characteristics of the metatarsal bones

The body is prismoid in form, tapers gradually from the tarsal to the phalangeal extremity, and is curved longitudinally, so as to be concave below, slightly convex above. The base or posterior extremity is wedge-shaped, articulating proximally with the tarsal bones, and by its sides with the contiguous metatarsal bones: its dorsal and plantar surfaces are rough for the attachment of ligaments. The head or anterior extremity presents a convex articular surface, oblong from above downward, and extending farther backward below than above. Its sides are flattened, and on each is a depression, surmounted by a tubercle, for ligamentous attachment. Its plantar surface is grooved antero-posteriorly for the passage of the flexor tendons, and marked on either side by an articular eminence continuous with the terminal articular surface.

[edit] Characteristics of the individual metatarsal bones

Figure 1 : The first metatarsal. (Left.)
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Figure 1 : The first metatarsal. (Left.)
Figure 2 : The second metatarsal. (Left.)
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Figure 2 : The second metatarsal. (Left.)
Figure 3 : The third metatarsal. (Left.)
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Figure 3 : The third metatarsal. (Left.)
Figure 4 : The fourth metatarsal. (Left.)
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Figure 4 : The fourth metatarsal. (Left.)
Figure 5 : The fifth metatarsal. (Left.)
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Figure 5 : The fifth metatarsal. (Left.)

[edit] The first metatarsal bone

('os metatarsale I; metatarsal bone of the great toe') [Fig. 1] The first metatarsal bone is remarkable for its great thickness, and is the shortest of the metatarsal bones. The body is strong, and of well-marked prismoid form. The base presents, as a rule, no articular facets on its sides, but occasionally on the lateral side there is an oval facet, by which it articulates with the second metatarsal. Its proximal articular surface is of large size and kidney-shaped; its circumference is grooved, for the tarsometatarsal ligaments, and medially gives insertion to part of the tendon of the Tibialis anterior; its plantar angle presents a rough oval prominence for the insertion of the tendon of the Peronæus longus. The head is large; on its plantar surface are two grooved facets, on which glide sesamoid bones; the facets are separated by a smooth elevation.

[edit] The second metatarsal bone

('os metatarsale II') [Fig. 2] The second metatarsal bone is the longest of the metatarsal bones, being prolonged backward into the recess formed by the three cuneiform bones. Its base is broad above, narrow and rough below. It presents four articular surfaces: one behind, of a triangular form, for articulation with the second cuneiform; one at the upper part of its medial surface, for articulation with the first cuneiform; and two on its lateral surface, an upper and lower, separated by a rough non-articular interval. Each of these lateral articular surfaces is divided into two by a vertical ridge; the two anterior facets articulate with the third metatarsal; the two posterior (sometimes continuous) with the third cuneiform. A fifth facet is occasionally present for articulation with the first metatarsal; it is oval in shape, and is situated on the medial side of the body near the base. The second metatarsal base acts as a "keystone (architecture)" (like in an arch) for the lisfranc joint. The base of the metatarsal is held firmly between the 1st & 3rd cuneiform.

[edit] The third metatarsal bone

('os metatarsale III') [Fig. 3] The third metatarsal bone articulates proximally, by means of a triangular smooth surface, with the third cuneiform; medially, by two facets, with the second metatarsal; and laterally, by a single facet, with the fourth metatarsal. This last facet is situated at the dorsal angle of the base.

[edit] The fourth metatarsal bone

('os metatarsale IV') [Fig. 4] The fourth metatarsal bone is smaller in size than the preceding; its base presents an oblique quadrilateral surface for articulation with the cuboid; a smooth facet on the medial side, divided by a ridge into an anterior portion for articulation with the third metatarsal, and a posterior portion for articulation with the third cuneiform; on the lateral side a single facet, for articulation with the fifth metatarsal.

[edit] The fifth metatarsal bone

('os metatarsale V') [Fig. 5] The fifth metatarsal bone is recognized by a rough eminence, the tuberosity, on the lateral side of its base. The base articulates behind, by a triangular surface cut obliquely in a transverse direction, with the cuboid; and medially, with the fourth metatarsal. On the medial part of its dorsal surface is inserted the tendon of the Peronæus tertius and on the dorsal surface of the tuberosity that of the Peronæus brevis. A strong band of the plantar aponeurosis connects the projecting part of the tuberosity with the lateral process of the tuberosity of the calcaneus. The plantar surface of the base is grooved for the tendon of the Abductor digiti quinti, and gives origin to the Flexor digiti quinti brevis. The base of the metatarsal is often injured and a particularly notorious fracture is the Jones fracture.

[edit] Articulations

The base of each metatarsal bone articulates with one or more of the tarsal bones, and the head with one of the first row of phalanges. The first metatarsal articulates with the first cuneiform, the second with all three cuneiforms, the third with the third cuneiform, the fourth with the third cuneiform and the cuboid, and the fifth with the cuboid.

[edit] Injuries

The metatarsal bones are often broken by soccer players, notably by David Beckham in 2002 and Wayne Rooney (a double fracture) in 2006, in both cases threatening their participation in World Cup tournaments. These and other recent cases have been attributed to the modern lightweight design of football boots, which give little protection to the foot.

[edit] Trivia

The Beckham bone is a name attributed by British journalists to the second metatarsal.

David Beckham, while playing for Manchester United against Deportivo La Coruña in a UEFA Champions League quarter-final game in 2002, was subject to a tackle from Argentina's Aldo Duscher. (A lot of acrimony had existed between David Beckham and Argentina since David Beckham's sending off in the 1998 World Cup). This tackle broke the second metatarsal in his left foot and seriously threatened England's chances in the 2002 World Cup.

David Beckham was the media darling at the time, and the bone (and the tackle) received a wave of publicity; subsequently, the name "Beckham bone" was born.

Since then, other notable football superstars including Ishaan Misra, Gary Neville, Danny Murphy, Michael Owen, Drew Peacock, Wayne Rooney and Mikael Silvestre have suffered fractures to the same bone. Wayne Rooney has broken his twice and underwent a scan on 7 June 2006 to assess whether he could play in the 2006 World Cup. Amid minor controversy he was declared fit to play.

[edit] Additional images

[edit] External links

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.

Human Bones
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VERTEBRAL COLUMN: vertebrae (cervical - atlas - axis | thoracic | lumbar) | sacrum | coccyx

THORAX: sternum | rib

cranial bones of SKULL: occipital | parietal | frontal | temporal | sphenoid | ethmoid

facial bones of SKULL nasal | maxilla | lacrimal | zygomatic | palatine | inferior nasal conchae | vomer | mandible | hyoid

UPPER EXTREMITY: clavicle | scapula | humerus | ulna | radius

carpals (scaphoid | lunate bone | triquetral | pisiform | trapezium | trapezoid | capitate | hamate) | metacarpals | phalanges (prox | int | dist)

LOWER EXTREMITY: pelvis (ilium, ischium, pubis) | femur | patella | fibula | tibia

tarsals (calcaneus | talus | navicular | cuneiform | cuboid ) | metatarsals | phalanges (prox | int | dist)

OSSICLES: malleus | incus | stapes


[edit] See also