Anatomy & Organs

Frontal bone – structure, function & diseases

Frontal bone

The frontal bone (lat. Os frontale ) is one of the human skull bones. Due to its frontal position, it is distinctive for the optics of the human face and also fulfills anatomically diverse important functions.

What is the frontal bone

The frontal bone sits in the upper frontal part of the human skull and thus partially encloses the brain . Likewise, it partially functions as the bone foundation for the human face .

Its scientific name Os frontale is derived from the Latin terms os ( bone ) and frons ( forehead ). The os frontale is involved in the formation of the anterior cranial fossa as well as the orbital roof and is usually unpaired in adult humans after the cranial bones have fused in the area of ​​the fontanelles.

The frontal sinuses as part of the paranasal sinuses are also contained within the frontal bone.

Anatomy & Structure

Anatomically, the frontal bone is roughly divided into three parts: the squama frontalis , also called frontal bone scales, the pars orbitalis , and the pars nasalis .

  • The squama frontalis , which in turn is divided into the facies externa and the facies interna, is designed vertically, corresponding to the human forehead. The facies externa refers to the outer surface, the facies interna refers to the surface of the squama frontalis on the inside of the skull.

Also characteristic of the human skull and that of primates are the so-called eyebrow ridges (Arcus superciliares) lying on the facies externa . These are typically more pronounced in men than in women.

  • The pars orbitalis forms the horizontal part of the frontal bone and consists of two triangular, thin bone plates, the orbital plates. Both orbital plates are pierced by a longitudinal seam. This part of the bone forms the roof of the human eye sockets as well as the nasal cavity.
  • The Pars nasalis forms the smallest section of the frontal bone and at the same time the connection between the two Partes orbitales. The spina nasalis protrudes from it, which together with the upper jaw (maxilla) and the nasal bone (os nasale) forms the root of the nose. The nasal cavity is bounded by the bony part of the pars nasalis.

Function & Tasks

The human skull serves primarily to protect the delicate brain and form the bony foundation for the human face. As a result, it is also divided into the brain skeleton ( neurocranium ) and the facial skeleton ( viscerocranium ). A special feature of the frontal bone is that the squama frontalis , as part of the anterior skullcap, is assigned to the cranium, while the pars orbitalis and pars nasalis come under the definition of the facial skeleton. Accordingly, the functions of the frontal bone are assigned to both task areas.

On the one hand, the squama frontalis covers the human brain on the frontal side of the head and thus protects against external violence and the associated injuries to the sensitive organ. This part of the frontal bone also contains the frontal sinus (frontal sinus), one of the paranasal sinuses. This is a paired cavity within the bone.

The frontal sinus is completely lined with mucous membrane and filled with air. It is primarily used to heat the breathing air and for the resonance of nasal sounds. Likewise, its function as a pneumatization space (air-filled cavity in the bone) is an expansion of the mucous membrane surface and thus defense against infection . This pneumatization space in the frontal bone also saves weight on the frontal bone, similar to other cranial bones.

The pars orbitalis is counted as part of the eye sockets (orbita) of the facial skeleton. The orbits form a cavity in the skull about 4-5 centimeters deep, in which the human eye and its appendages are embedded. They serve as bony protection for the sensitive visual organs. Likewise, the openings on the inside allow the passage of nerves , blood vessels and the tear duct .

The pars nasalis belongs to the roof of the nasal cavity, which in turn belongs to the upper respiratory tract. This interior of the nose is connected to the outside world through the nostrils and thus enables the supply of vital breathing air.

Diseases & Ailments

Pain in the frontal bone can indicate a variety of complaints. Very often, these are headaches caused by excessive stress and a lack of time for both physical and mental rest. With short relaxation units in everyday life, however, the symptoms can usually be counteracted without any problems.

Headaches in the forehead area are also often among the main complaints in patients with migraines and cluster headaches . The exact causes of the latter two diseases are still unclear to this day, but in most cases so-called “triggers” can be identified, triggers for the recurring headache attacks. These vary greatly from person to person, but once they have been identified, they can be avoided in a targeted manner.

Eye problems can also be the cause of the pain mentioned. Poor eyesight or other eye diseases are a frequent trigger for headaches in the forehead and eye area and can go unnoticed by those affected without clarification by a specialist.

In the context of colds , there is always the risk of sinusitis , an inflammatory change in the mucous membrane of the paranasal sinuses caused by bacteria or viruses. The frontal sinus as part of the paranasal sinuses can be affected by this disease and cause the patient a boring pain accompanied by a feeling of pressure.

Sinusitis can be acute or chronic and requires different treatment methods depending on the severity. These can range from a simple administration of herbal medicines to the necessary surgery.

If pain occurs in the above-mentioned area after external violence such as a bump or blow, this can be an indication of a skull or craniocerebral trauma . The severity can also vary greatly here. Depending on the type and duration of the pain and any additional symptoms that may occur, such as nausea or impaired consciousness , this can range from injuries that do not require further treatment to life-threatening injuries. Obtaining medical advice after head injuries is always recommended.

Lisa Newlon
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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.