[Biomechanical comparison of various emergency stabilization measures of the pelvic ring]

Abstract

Massive bleeding with shock is still the most frequent reason for early death after complex pelvic trauma. For hemostasis, fracture stabilization in the pelvic ring is an important aspect. By use of the external fixator and introduction of emergency pelvic c-clamps, attempts were made to include pelvic ring stabilization on the early resuscitation algorithm. This biomechanical study compared a simple anterior external fixator (one supraacetabular pin on each side), the emergency pelvic c-clamp (Ganz) and the Browner modification of the clamp ("ACE clamp"). Two fresh-frozen human cadaver pelves were loaded in a one-leg stance model. The displacement and rotations on the site with the fracture were measured with a 3D measurement system. Fracture models included a Tile type B injury and two Tile type C instabilities (pure SI dislocation; transforaminal sacrum fracture). In type B injuries all methods withstood loading with 100% of the body weight (640/700 N). In C-type injuries with SI dislocation the external fixator showed no significant holding force, whereas the two c-clamps withstood loading of 112 N and 160 N. In the transforaminal fracture model no one method withstood a load of more than 40 N. The combination of the clamps with the external fixator increased the holding strength to 66 N and 103 N. Although a single-leg-stance model does not reflect the emergency situation, in which the patient is normally in a supine position, the data recorded are comparable to those observed in earlier investigations.(ABSTRACT TRUNCATED AT 250 WORDS)