FORENSICS

Osteology: Metatarsals

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There are five metatarsal bones.  The metatarsals are often referred to by the abbreviation “MT” plus the number of the ray to which they belong.  Thus, MT1 is the first metatarsal or the big toe metatarsal.  Like the metacarpals, each metatarsal is a tubular bone, with an expanded base which articulates with one or more tarsal bones, and a rounded head which articulates with a pedal phalanx.  The metatarsal heads are more compressed medio-laterally than the metacarpal heads.  It is much easier to identify and side metatarsals using their bases than their heads.

Return to the tarsus or pedal phalanges for more information about the ankle, foot, and toes.




Metatarsal  1


Metatarsal 2


Metatarsal 3


Metatarsal 4

Metatarsal 5



The first metatarsal is broad, robust, and short compared with the rest of the metatarsals.  The proximal end bears a saddle-shaped articular surface for the medial cuneiform.  A tuberosity of the proximal end projects towards the plantar surface. The plantar aspect of the phalanx articulation bears two grooves for sesamoid bones of the flexor tendons.

Siding MT1

To side the bone, the tuberosity is plantar.


The second metatarsal is the usually the longest metatarsal.  In proximal view, the base is triangular, with the point pointing towards plantar.  The single proximal facet is for the intermediate cuneiform.  The medial side of the base has a small articular surface for the medial cuneiform. The lateral side of the base bears two facets, one each for the lateral cuneiform and and MT3.

Siding MT2

Position the bone such that the proximal articular surface is flat (as if resting on a table) and view the bone from the plantar aspect.  The metatarsal leans medially, towards the side from which the bone comes.


The third metatarsal is very similar to MT2 but the number of facets on the medial and lateral sides of the base is reversed.  MT3 has a single lateral facet for MT4 and two medial facets which both articulate with MT2.  The proximal surface of the base articulates with the lateral cuneiform.

Siding MT3

Position the bone such that the proximal articular surface is flat (as if resting on a table) and view the bone from the plantar aspect.  The metatarsal leans medially, towards the side from which the bone comes.

The fourth metatarsal is distinguishable due to the oval shape of its base in proximal view.  The base bears a large articular surface on its dorsal-medial side with facets for the lateral cuneiform and MT3.  There is occasionally a small facet on the plantar-medial side for MT3 as well.  The lateral side bears an oval-shaped facet for the cuboid.

Siding MT4

Position the bone such that the proximal articular surface is flat (as if resting on a table) and view the bone from the plantar aspect.  The metatarsal leans medially, towards the side from which the bone comes.


The base of the fifth metatarsal has an extremely distinctive shape due to its blunt styloid process which projects laterally and proximally.  The proximal articular facet is for the cuboid.  The cuboid facet is analogous to the medial facet for MC4.  These two facets meet at an obtuse angle.

Siding MT5

Position the bone such that the proximal articular surface is flat (as if resting on a table) and view the bone from the plantar aspect.  The metatarsal leans medially, towards the side from which the bone comes.



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