CorpusHuman Anatomy
SkeletalBone

Palatine bone

Os palatinum

A paired L-shaped bone at the back of the nasal cavity forming the posterior third of the hard palate, part of the lateral nasal wall and a small part of the orbital floor.

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Overview

Each palatine bone has a horizontal plate, which meets its fellow and the palatine processes of the maxillae to form the posterior third of the hard palate (its free posterior border attaches the soft palate and bears the posterior nasal spine), and a perpendicular plate forming the posterior lateral wall of the nasal cavity, with conchal and ethmoidal crests for the inferior and middle conchae. Three processes arise from it: the pyramidal process (fits between the pterygoid plates), the orbital process (small part of the orbital floor) and the sphenoidal process; the notch between the latter two, closed by the sphenoid body, forms the sphenopalatine foramen.

The greater palatine foramen (greater palatine nerve and vessels), near the third molar, and the lesser palatine foramina (to the soft palate) open on the palate. The perpendicular plate forms the medial wall of the pterygopalatine fossa.

Location

Posterior part of the nasal cavity and hard palate, between maxilla and pterygoid process of the sphenoid.

Parts & subdivisions

  1. Horizontal plate
    Posterior third of the hard palate.
  2. Perpendicular plate
    Posterior lateral nasal wall; medial wall of the pterygopalatine fossa.
  3. Greater and lesser palatine foramina
    Greater and lesser palatine nerves (V2) and vessels; site for the greater palatine nerve block.
  4. Sphenopalatine foramen
    Sphenopalatine artery and nasopalatine/posterior nasal nerves enter the nasal cavity.
  5. Orbital process
    Small posterior part of the orbital floor.

Anatomy

Articulations

Maxilla, sphenoid, ethmoid, inferior nasal concha, vomer and opposite palatine bone.

Ossification

Intramembranous, single centre ≈week 8 in the perpendicular plate.

Function

  • Completes the hard palate posteriorly
  • Forms part of the nasal cavity walls and floor
  • Contributes to the orbit and pterygopalatine fossa

Clinical significance

Posterior epistaxis

Bleeding from branches of the sphenopalatine artery (entering via the sphenopalatine foramen) is harder to control than anterior (Kiesselbach plexus) bleeds and may need posterior packing or endoscopic ligation.

Compiled from standard anatomy and physiology references — see the Skeletal System sources. For education only; not medical advice.