The bony structure beneath the eyebrow, often called the eyebrow bone, can be broken, though it is not a frequent injury. This robust part of the skull is designed for protection. A fracture in this area, technically called a supraorbital rim fracture, indicates that a significant force has overcome the natural defenses of the human face. This injury is serious because of the bone’s proximity to the eyes, sinuses, and brain.
The Bone Structure Under the Eyebrow
The bone structure commonly referred to as the eyebrow bone is anatomically known as the supraorbital ridge or the superciliary arch. This ridge is a prominent, thickened arch of the frontal bone, which is the large, flat bone that makes up the forehead. It forms the upper and outer boundary of the eye socket, or orbit, serving as a natural shield for the eye and the delicate structures within the orbit.
The supraorbital ridge is one of the densest and strongest parts of the facial skeleton. Its primary function is to provide mechanical protection against impact to the eyes and to support the soft tissues of the forehead. The ridge is typically more pronounced in men than in women, but it creates a bony buffer zone. Directly behind this ridge is the frontal sinus, a hollow space within the bone, which can sometimes be involved in a fracture.
Forces Required to Cause a Fracture
Fractures of the supraorbital rim are rare compared to other facial fractures because of the bone’s robust nature. When these fractures do occur, they are nearly always the result of significant, high-energy blunt force trauma. The mechanism of injury must be powerful enough to overcome the inherent strength of the frontal bone.
The most frequently reported causes include motor vehicle collisions, severe falls from a height, or direct, high-velocity impacts during sports or assault. Isolated supraorbital rim fractures are uncommon; they often occur concurrently with other craniomaxillofacial injuries, such as fractures to the frontal sinus or other parts of the orbit. The force of impact is typically focused directly onto the ridge, causing the thick bone to fracture or depress inward toward the eye socket or brain cavity.
Identifying Signs of a Supraorbital Fracture
The signs and symptoms following a supraorbital fracture are often severe and require immediate medical attention. Localized, intense pain and significant swelling around the eye and forehead are immediate indicators of trauma. Severe bruising, which may spread around the eye socket to create a “raccoon eye” appearance, results from blood pooling beneath the skin (periorbital ecchymosis).
A specific and concerning symptom is numbness or a tingling sensation (paresthesia) in the forehead or scalp above the eyebrow. This symptom occurs when the supraorbital nerve, which runs through a notch or foramen in the ridge, is stretched, compressed, or damaged by the fractured bone segments. In more severe cases, a visible step deformity or depression in the bony ridge may be felt upon gentle palpation.
Visual disturbances are a serious complication if the fracture affects the orbital roof or surrounding structures. Patients may experience double vision (diplopia) due to the displacement of the eye or restriction of eye movement. The eyeball may appear sunken (enophthalmos) or pushed forward (proptosis), and any change to vision demands immediate evaluation by a specialist.
Diagnosis and Treatment Options
Diagnosis of a supraorbital fracture begins with a detailed clinical examination, but imaging is necessary to determine the full extent of the injury. A Computed Tomography (CT) scan is the preferred imaging modality, as it provides high-resolution, three-dimensional detail of the bone structure, which is superior to standard X-rays. The CT scan helps medical professionals assess the displacement of the bone fragments, the involvement of the frontal sinus, and any possible damage to the orbital contents.
Treatment is highly dependent on the fracture’s severity and whether the bone fragments are displaced. If the fracture is non-displaced and stable, treatment may involve only conservative management, such as observation, pain control, and avoiding activities that could cause further injury. Fractures that are displaced, involve the eye socket, or affect the frontal sinus often require surgical intervention.
Surgical treatment typically involves an approach called Open Reduction and Internal Fixation (ORIF). During this procedure, the surgeon accesses the fracture site, carefully repositions the bone fragments, and secures them with small metal plates and screws. This stabilization is necessary to restore the normal contour of the orbital rim and protect the underlying structures. Recovery time varies widely but can involve several weeks of restricted activity and follow-up imaging to ensure proper healing.
Identifying Signs of a Supraorbital Fracture
The signs and symptoms following a supraorbital fracture are often severe and require immediate medical attention. Localized, intense pain and significant swelling around the eye and forehead are immediate indicators of trauma. Severe bruising, which may spread around the eye socket to create a “raccoon eye” appearance, results from blood pooling beneath the skin (periorbital ecchymosis).
A specific and concerning symptom is numbness or a tingling sensation (paresthesia) in the forehead or scalp above the eyebrow. This symptom occurs when the supraorbital nerve, which runs through a notch or foramen in the ridge, is stretched, compressed, or damaged by the fractured bone segments. In more severe cases, a visible step deformity or depression in the bony ridge may be felt upon gentle palpation.
Visual disturbances are a serious complication if the fracture affects the orbital roof or surrounding structures. Patients may experience double vision (diplopia) due to the displacement of the eye or restriction of eye movement. The eyeball may appear sunken (enophthalmos) or pushed forward (proptosis), and any change to vision demands immediate evaluation by a specialist.
Diagnosis and Treatment Options
Diagnosis of a supraorbital fracture begins with a detailed clinical examination, but imaging is necessary to determine the full extent of the injury. A Computed Tomography (CT) scan is the preferred imaging modality, as it provides high-resolution, three-dimensional detail of the bone structure, which is superior to standard X-rays. The CT scan helps medical professionals assess the displacement of the bone fragments, the involvement of the frontal sinus, and any possible damage to the orbital contents.
Treatment is highly dependent on the fracture’s severity and whether the bone fragments are displaced. If the fracture is non-displaced and stable, treatment may involve only conservative management, such as observation, pain control, and avoiding activities that could cause further injury. Fractures that are displaced, involve the eye socket, or affect the frontal sinus often require surgical intervention.
Surgical treatment typically involves an approach called Open Reduction and Internal Fixation (ORIF). During this procedure, the surgeon accesses the fracture site, carefully repositions the bone fragments, and secures them with small metal plates and screws. This stabilization is necessary to restore the normal contour of the orbital rim and protect the underlying structures. Recovery time varies widely but can involve several weeks of restricted activity and follow-up imaging to ensure proper healing.