Classification of depressed skull fractures

A depressed fracture actually refers to a situation where the fracture area is locally depressed. A depressed skull fracture refers to such a situation in the skull area, which is generally caused by an external force that is large but not fast.

Depressed fracture of the skull refers to a type of fracture characterized by a local depression of the bone plate (mostly more than 0.5 cm). It can occur alone or in combination with linear fractures. It can usually be formed when the impact area of ​​the wounding object is limited, the force is large and the speed is slow. It is most common when a blunt object hits you, but can also be seen when a sharp object cuts you. Depressed fractures are generally more localized and can better reflect the size and shape of the impact surface of the injury.

More specific types of depressed fractures

Ping-pong fracture

It is usually seen in infants and young children because their skull is mainly composed of organic components, which are elastic and not easily broken when injured. Only the local skull under force is compressed and deformed like a ping-pong ball, but no fracture line appears. The injured generally have no obvious symptoms of brain damage and can usually recover on their own.

Scaphoid fracture

It refers to a fracture that is concave like a boat. It is generally seen when a stick is hit vertically with force. It can also be seen when a sharp object is cut vertically. There are some differences between the two types of boat-shaped fractures. The deepest part of the depression of the scaphoid fracture is the main fracture line. The fracture fragments on both sides are obliquely depressed, and there are accompanying fracture lines on the edges of the depressed fracture. For injuries caused by sharp objects, the periosteum at the main fracture line is neatly split, and shallow or deep cuts may be left on the outer plate of the skull (local defects in the outer plate); while those caused by blunt objects (such as sticks) do not have these characteristics, but the main fracture line in the middle is not straight, and even branched extended fracture lines can be seen.

Step fracture

It refers to the depressed fracture fragments that sink in layers in a stepped manner. It is more common when the hammer or axe back strikes at an angle. The edge of a depressed fracture sometimes shows a bone compression edge formed by local collapse of the outer plate, which is considered to be a characteristic of blunt metal impact.

Ring fracture

It occurs when the round hammer or axe back strikes the skull vertically. When the action surface causes the skull it contacts to sink downward, due to the conduction of force, a circular fracture line or a radial fracture line may appear at the same time.