Depressed Fracture
Definition
A fracture where the impacted skull segment is driven inward beyond the elastic limit; the geometry of the depression reflects the bearing surface of the implement at the moment of impact.
- Location
- Cranial vault, at point of impact
- Mechanism
- Localised force exceeding bone's elastic limit
- Diagnostic value
- Geometry reflects impacting object's surface
- Related patterns
- Radiating and concentric fractures
Common questions
What can the shape of a depressed fracture tell an examiner about the weapon?+
The outline and contour of the depressed segment can approximate the size and shape of the striking surface, such as a hammer face or pipe edge, letting the examiner narrow the type of implement, though it rarely identifies a specific object uniquely.
How does a depressed fracture relate to radiating and concentric fractures at the same site?+
A depressed fracture is the localised inward failure directly under the impact, while radiating fractures extend outward from that point and concentric fractures form rings around it as the bone deforms; all three commonly occur together from a single significant blunt impact and are read as a set.
Related terms
- Bearing Surface
- The area of the striking implement that was in contact with the skull at the moment of force transfer; its geometry can...
- Concentric Fracture
- An arc-shaped fracture encircling the impact zone, produced by outer-table bending tension at a distance from the focal impact; always post-dates the...
- Diffuse Loading
- Force distributed over a broad contact area (as from a fall onto a flat surface or a broad-surface blow); produces a broader...
- Focal Loading
- Force concentrated on a small contact area of the skull surface (as from a hammerhead, poker, or stone edge); produces a discrete...
- Hering's Principle
- The 1853 observation that a radiating fracture from a subsequent impact is arrested when it reaches a fracture line produced by a...
- Perimortem Fracture
- A fracture produced at or near the time of death while the bone retains green (fleshed) properties; distinguished by sharp fracture margins...
- Radiating Fracture
- A linear fracture extending outward from the impact point, initiated by inner-table tension as the outer table is compressed; propagates until arrested...
- Wedge Fracture
- The three-dimensional fracture geometry described by Berryman and Symes (1998): a conical inner-table failure zone wider than the outer-table defect, produced by...
- Wolff's Law
- The principle that bone is deposited and resorbed in response to mechanical loading history. Cortical thickness and trabecular orientation follow principal stress...