Topics

Topic

design image
Metatarsophalangeal joint of great toe

The metatarsophalangeal (MTP) joint of the great toe, also called the first MTP joint, is a synovial condyloid joint formed between the head of the first metatarsal and the base of the proximal phalanx of the hallux. It plays a critical role in weight-bearing, balance, and propulsion during gait.

It is a key anatomical structure in foot biomechanics, sports medicine, podiatry, and musculoskeletal imaging.

Synonyms

  • First MTP joint

  • Hallux metatarsophalangeal joint

Location

  • Situated at the base of the great toe

  • Between the first metatarsal head and proximal phalanx

  • Anterior to the first metatarsal

  • Inferior to the distal first metatarsal metaphysis

  • Forms the medial-most MTP joint of the forefoot

Anatomical components

  • Articulating bones:

    • Head of the first metatarsal

    • Base of the proximal phalanx

  • Joint capsule:

    • Fibrous capsule enclosing the joint

  • Plantar plate:

    • Thick fibrocartilaginous structure reinforcing the plantar aspect

  • Sesamoid apparatus:

    • Medial (tibial) and lateral (fibular) sesamoid bones embedded in flexor hallucis brevis

  • Collateral ligaments:

    • Medial and lateral stabilizing ligaments

Relations

Anteriorly:

  • Extensor hallucis longus tendon

  • Dorsal joint capsule

Posteriorly (plantarly):

  • Flexor hallucis longus tendon

  • Sesamoid bones and plantar plate

Medially:

  • Abductor hallucis tendon

  • Medial collateral ligament

Laterally:

  • Adductor hallucis tendon

  • Lateral collateral ligament

Superiorly (dorsally):

  • Skin and subcutaneous tissue of the forefoot

Inferiorly (plantarly):

  • Plantar soft tissues and fat pad

X-ray appearance

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

  • Joint space: Well-defined between metatarsal head and proximal phalanx

  • Metatarsal head: Rounded articular surface

  • Sesamoids: Seen beneath the metatarsal head on AP and axial views

  • Alignment: First metatarsal and phalanx in proper axial orientation

CT appearance

Non-contrast CT:

  • Articular surfaces: Clearly delineated cortical margins

  • Joint space: Well visualized between the articulating bones

  • Sesamoid bones: Precisely defined in size, shape, and position

  • Subchondral bone: Trabecular detail well demonstrated

MRI appearance

T1-weighted images:

  • Bone marrow: High signal in metatarsal head and proximal phalanx

  • Cortical bone: Low signal

  • Joint space: Intermediate signal

  • Sesamoids: Low-to-intermediate signal

T2-weighted images:

  • Joint fluid: High signal outlining articular surfaces

  • Cartilage: Intermediate signal

  • Plantar plate and ligaments: Low signal

STIR:

  • Fat suppression: Uniform suppression of marrow fat

  • Joint fluid: Bright signal

  • Sesamoids and ligaments: Low signal against suppressed background

Proton density fat-saturated (PD FS):

  • Joint fluid: High signal

  • Cartilage surfaces: Well visualized

  • Collateral ligaments and plantar plate: Low-signal linear structures

CT VRT 3D image

Metatarsophalangeal joint of great toe 3D

MRI image

Metatarsophalangeal joint of great toe mri anatomy labelled image-img-00000-00000

CT image

Metatarsophalangeal joint of great toe 2

CT image

Metatarsophalangeal joint of great toe CT