More straightforward ankle fracture classification suggested

Jun 05, 2009

The factor that determines the fracture pattern in the ankle may be a combination of the external rotational moment and the abduction moment. Counterexamples to the Lauge-Hansen classification system show that a short oblique fracture of the distal end of the fibula may occur with the foot in the pronated position before medial injury, the latter preceding or following posterior ligament rupture or avulsion fracture of the posterior malleolus, and that lateral forces applied to the foot affect fracture type.

The factor that determines the fracture pattern in the ankle may be a combination of the external rotational moment and the abduction moment. Counterexamples to the Lauge-Hansen classification system show that a short oblique fracture of the distal end of the fibula may occur with the foot in the pronated position before medial injury, the latter preceding or following posterior ligament rupture or avulsion fracture of the posterior malleolus, and that lateral forces applied to the foot affect fracture type.

Haraguchi and Armiger subjected 23 cadaver ankles to fracture loading that copied the Lauge-Hansen pronation/external rotation mechanism, with or without the application of external lateral force. With radiographic and macroscopic dissection data, fracture types were determined using Lauge-Hansen's objective criteria.

About half the ankles tested during the first phase sustained an oblique fracture of the distal end of the fibula. In the second phase, adding an external lateral force caused a high fibular fracture with a reversed fracture line or a comminuted high fibular fracture or both in 3 specimens. The distribution of traditional pronation-external rotation-type fractures differed significantly between phases.

The authors noted that development of a simpler classification system for ankle fractures based on applied loads might be beneficial.