Hinge Fracture
Definition
A curved crack running from the deepest point of a chop kerf to the opposite cortex, producing a free-floating triangular fragment; characteristic of high-energy chopping force.
- Path
- From the deepest point of the kerf to the opposite cortex
- Shape
- Curved crack
- Result
- Free-floating triangular bone fragment
- Cause
- High-energy chopping force
Common questions
What does the triangular fragment produced by a hinge fracture tell an examiner?+
Its presence indicates the impact carried enough kinetic energy to drive the crack all the way through to the far cortex rather than only chipping the near surface, which helps distinguish a forceful chop from a shallower cutting or scraping injury on the same bone.
How is a hinge fracture distinguished from ordinary radiating fractures in blunt trauma?+
A hinge fracture is specifically associated with a sharp chopping instrument striking bone and produces a curved, kerf-linked crack with a distinct free fragment, whereas blunt-force radiating fractures spread outward from an impact point without that kerf origin or triangular piece.
Related terms
- Breakaway Spur
- A chip or spur of cortical bone on the exit face of a saw kerf, produced when the final tooth exits the...
- Class Characteristics
- Features deliberately or systematically imparted to a group of items by design or manufacture, such as the calibre of a bullet, the...
- False-Start Kerf
- A short, incomplete saw mark adjacent to the main kerf, produced when the cutter repositioned the saw after an unsatisfactory initial entry...
- Incised Wound
- A wound produced by a sharp-edged implement. Margins are clean, without contusion or bridging. Depth is less than length in a classic...
- Kerf
- The groove or channel cut into bone by a sharp implement; its width, wall angle, floor texture, and profile are the primary...
- Kerf Wall Squareness
- The angle of the kerf walls relative to the bone surface; square walls indicate a stable, perpendicular saw stroke; canted walls indicate...
- Residual Tooth Marks
- Individual tooth impressions in the floor of an incomplete saw kerf, allowing direct measurement of tooth geometry and TPI when the saw...
- Tooth Set
- The lateral bending of saw teeth alternately left and right of the blade body, producing a kerf wider than the blade itself;...
- TPI (Teeth per Inch)
- The number of teeth on a saw blade per inch of blade length; determines the spacing of striation marks on the kerf...