The vomer is an unpaired bone of the facial skeleton, characterized by its small size and thin, quadrilateral shape. Its name is derived from the Latin word for a plowshare, describing its flattened form. Situated in the midline of the skull, the vomer acts as a central partition. It connects several other facial and cranial bones, establishing the core structural integrity of the nasal cavity.
Anatomical Placement in the Skull
The vomer is positioned vertically and centrally within the skull. Its location is inferior and posterior within the nasal cavity, contributing significantly to the bony structure of the face. The bone is trapezoidal in outline and features four borders, which articulate with a total of six different bones.
The superior border is the thickest part, extending laterally into two wing-like projections called the alae of the vomer. This border fits into a deep furrow on the sphenoid bone, anchoring the vomer to the base of the skull. This superior connection provides stability for the nasal septum.
The inferior border articulates with the crest formed by the maxillae (upper jaw bones) and the palatine bones. The longest border, the anterior border, slopes forward and downward. It connects superiorly with the perpendicular plate of the ethmoid bone and inferiorly with the septal cartilage of the nose. This set of connections ensures the vomer is securely locked into the center of the facial skeleton.
The posterior border does not articulate with any other bone. This concave, free border separates the two posterior nasal apertures, which lead from the nasal cavity into the nasopharynx. Along its surfaces, the vomer contains oblique grooves that accommodate the passage of nerves and blood vessels, such as the nasopalatine nerve and vessels.
Primary Function in Nasal Passage Structure
The primary role of the vomer is to form the posteroinferior portion of the nasal septum. The nasal septum is the wall that separates the internal nasal cavity into two passages. The vomer, along with the perpendicular plate of the ethmoid bone and the septal cartilage, creates this complete midline partition.
This structural separation is necessary for the proper regulation of airflow. Dividing the cavity ensures that air is efficiently funneled and conditioned as it passes toward the lungs. The vomer’s position supports the overlying mucous membranes, which warm, humidify, and filter the inhaled air.
The structural integrity provided by the vomer also supports the upper nasal region, which contains the olfactory epithelium. This specialized tissue is responsible for the sense of smell. By maintaining the correct architecture of the nasal cavity, the vomer indirectly supports the function of the olfactory system.
Common Clinical Issues Involving the Vomer
The vomer’s central location makes it a common factor in structural problems within the nose, most frequently contributing to a condition known as a deviated septum. A deviated septum occurs when this midline wall is displaced or bent away from the center. The vomer, being a bony component of the lower septum, can be crooked or develop bony spurs that project into one of the nasal passages.
This displacement can impair breathing by obstructing the flow of air through the narrowed passage. While many individuals have some degree of septum deviation without symptoms, a pronounced deviation involving the vomer may require a septoplasty to correct the alignment. During this surgical procedure, a surgeon may reshape or remove deviated portions of the vomer to restore the airway.
Physical trauma to the face is another common issue, as the vomer is a thin bone that can be fractured. The connection points, particularly where it meets the ethmoid and sphenoid bones, are susceptible to injury. A fracture can cause acute pain and contribute to a severe nasal obstruction, necessitating medical intervention to stabilize the nasal structure.