Topics

Topic

design image
Head of first metatarsal bone

The head of the first metatarsal bone is the rounded distal articular end of the first metatarsal and forms the proximal component of the first metatarsophalangeal (MTP) joint. It plays a critical role in weight-bearing, push-off during gait, and stabilization of the medial longitudinal arch of the foot.

It is a key anatomical landmark in forefoot anatomy, sports medicine, podiatry, and foot imaging.

Synonyms

  • First metatarsal head

  • Metatarsal I head

Location

  • Situated at the distal end of the first metatarsal bone

  • Forms the proximal articular surface of the first MTP joint

  • Located medial and anterior in the forefoot

  • Superior to the sesamoid bones

  • Inferior to the proximal phalanx of the great toe

Anatomical components

  • Rounded articular surface:

    • Covered by hyaline cartilage

  • Plantar grooves:

    • Accommodate the medial and lateral sesamoid bones

  • Cortical shell and cancellous core

  • Capsular and ligamentous attachments:

    • Joint capsule

    • Collateral ligaments

    • Plantar plate

Relations

Anteriorly:

  • Base of the proximal phalanx of the great toe

Posteriorly:

  • Neck of the first metatarsal

Inferiorly (plantar):

  • Medial and lateral sesamoid bones

  • Flexor hallucis brevis tendons

Superiorly (dorsal):

  • Extensor hallucis longus tendon

Medially:

  • Medial collateral ligament of the first MTP joint

Laterally:

  • Lateral collateral ligament of the first MTP joint

X-ray appearance

Plain radiographs (AP, oblique, and lateral foot views):

  • Head: Seen as a rounded distal articular contour of the first metatarsal

  • Joint space: Clearly visualized with the proximal phalanx

  • Sesamoids: Seen inferior to the head on specialized views

  • Cortical outline: Smooth and well-defined

CT appearance

Non-contrast CT:

  • Head of first metatarsal: Well-defined rounded bony structure

  • Cortical margins: Smooth and sharply outlined

  • Trabecular pattern: Normal cancellous bone texture

  • Articular surface: Clearly demonstrated

  • Relationship to sesamoids: Well visualized

MRI appearance

T1-weighted images:

  • Cortical bone: Low signal intensity

  • Marrow within head: High signal intensity

  • Articular cartilage: Intermediate signal outlining joint surface

T2-weighted images:

  • Cortex: Low signal

  • Joint fluid: High signal in the first MTP joint

  • Cartilage: Intermediate-to-high signal relative to bone

STIR:

  • Fat suppression: Uniform suppression of marrow fat

  • Joint recesses: Bright signal

  • Soft-tissue contrast: Clear delineation of capsule and tendons

Proton density fat-saturated (PD FS):

  • Marrow fat: Suppressed

  • Articular cartilage: Well delineated

  • Sesamoids and plantar plate: Clearly visualized

  • Ligamentous structures: Seen as low-signal bands

MRI image

Head of first metatarsal bone mri anatomy labelled image-img-00000-00000

CT VRT 3D image

Head of first metatarsal bone