Skull fracture

Introduction The skull is a spherical shell that houses and protects the contents of the cranial cavity. A skull fracture is a disease in which one or more pieces of the head bone are partially or completely broken, mostly due to a blunt impact. The importance of skull fractures is not in the skull fracture itself, but in the concurrent damage of the cranial cavity. According to the shape of the fracture, it is classified into: linear fracture, depressed fracture, comminuted fracture, and child growth fracture. A fractured piece of a depressed or comminuted fracture can damage the meninges and brain and damage the cerebral blood vessels and cranial nerves. Skull fractures account for about 15-20% of craniocerebral injury, which can occur in any part of the skull, with the largest amount of parietal bone, followed by the frontal bone, followed by the humerus and occipital bone. Generally, the fracture line does not cross the cranial suture. If the violence is too large, it can also affect the adjacent bone. The positive lateral position of the skull can be diagnosed. Because of the different fracture morphology, the treatment and prognosis are also different.

Cause

The occurrence of a skull fracture is the result of the reaction force generated by the violence on the skull. If it is revealed that it moves in the direction of the violent action and does not form a reaction, it will not cause a fracture. Since the anti-stretching strength of the skull is always less than the compressive strength, when the violence is applied, the part that always bears the tension first breaks. If the striking area is small, the local shape of the skull is mostly changed to the main; if the area of the force is large, the overall deformation of the skull can be caused, often accompanied by extensive brain damage.

an examination

Related inspection

Brain CT examination X-ray cephalometric measurement

The incidence of linear fractures in the cranial cap is the highest, mainly confirmed by the skull x-ray film. The diagnosis and localization of skull base fractures are mainly determined by the above clinical manifestations. The delayed onset of blood spots, specific parts, and direct points of action that are not violent, can be distinguished from simple soft tissue contusions. When there is a doubt about cerebrospinal fluid leakage, the effluent can be collected for quantitative determination of glucose to determine. When there is a cerebrospinal fluid leak, it is actually an open brain injury. Ordinary X-ray films can show intracranial gas accumulation, but only 30% to 50% can show fracture lines; CT examination is not only helpful for the diagnosis of orbital and optic canal fractures, but also for brain damage.

Local deformation of the skull:

After the skull cover is hit, the force part first dents. If the violence is fast, the area of action is small, and the elastic range of the skull is not exceeded, the skull will rebound immediately; if it exceeds the elastic range, the center of the force will fall into the cone of the cranial cavity, causing bone rupture in the first and second. If the rupture stops at the inner plate, it is a simple inner plate fracture, and there may be a chronic headache in the later stage; if the outer plate is also broken, a local depression and a peripheral annular and linear fracture are formed. If the violent effect of the injury is still not exhausted, the fracture piece can be trapped in the cranial cavity, forming a crushing depression or a hole-shaped fracture.

Overall deformation of the skull:

The skull can be simplified into a hemispherical model with a hemispherical surface and a skull base. After being stressed, the skull can be deformed as a whole. When the direction of violence is lateral, the fracture is usually perpendicular to the sagittal line, folded to the ankle and skull base; the violence is in the anteroposterior direction, the fracture line is often parallel to the sagittal line, forward to the anterior cranial fossa, and backward to the occipital bone, severe Can cause sagittal suture fractures. In addition, when the violence acts vertically on the central axis of the body, it can be transmitted to the skull base along the spine. The lighter causes a linear fracture of the skull base, and the severe one can cause a life-threatening skull base fracture and fall into the skull.

Regularity of skull fractures:

The direction, speed and area of the violent effect have a great influence on the skull fracture, which is summarized as follows: the force axis of the violent action and its main component direction are more consistent with the direction of the fracture line, but the thickened skull arch is encountered. When the beam structure is used, it often folds to the weak part of the bone. When the area of violence is small and the speed is fast, a hole-shaped fracture often occurs, and the bone piece falls into the cranial cavity. If the striking area is large and the speed is fast, it will cause partial crushing and sag fracture; if the area of the action point is small and the speed is slow, it will often cause a linear fracture through the point of force; if the area of the action point is large and the speed is slow, Can cause comminuted fractures or multiple linear fractures. Strike perpendicular to the skull is likely to cause local depression or comminuted fracture; oblique strikes multi-linear fractures and extend in the direction of the force axis; often to the skull base; occipital stress often causes occipital fracture or extension to Department and fracture of the middle cranial fossa.

Differential diagnosis

1, skull fracture:

According to the fracture form, it is divided into linear fracture and concave fracture.

The principle of treatment is surgical reduction.

Surgical indications:

(1) The depth of the fracture piece into the cranial cavity is above 1 cm.

(2) A large area of the fracture piece is caught in the cranial cavity, and the intracranial pressure is increased due to bone compression or blood.

(3) Because the fracture piece compresses the brain tissue, causing signs of nervous system or epilepsy. A depressed fracture located in the sinus of the large sinus, such as a neurological sign or an increase in intracranial pressure, should also be operated, and vice versa. Adequate blood transfusion equipment must be prepared before surgery to prevent major bleeding during fracture reconstruction.

2, skull base fracture:

The majority of skull base fractures are linear fractures, and some are concave fractures. According to their location, they are divided into: anterior cranial fossa, middle cranial fossa, and posterior fossa fracture.

Most of these fractures do not require special treatment, but focus on combined brain damage and other concurrent injuries. Otorrhea and cerebrospinal fluid leakage, can not be blocked or washed, so as not to cause intracranial infection. Most cerebrospinal fluid leakage can stop itself in about two weeks. If it lasts for more than four weeks or with the accumulation of gas in the brain for a long time, it should be operated in time to repair the cerebrospinal fluid and close the mouth. For optic nerve or facial nerve injury caused by crushing of bone fragments, the bone fragments should be removed as soon as possible. Skull base fractures with cerebrospinal fluid leakage are open injuries and require antibiotic treatment.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.