Ce. Dunning et al., Supplemental pinning improves the stability of external fixation in distalradius fractures during simulated finger and forearm motion, J HAND S-AM, 24A(5), 1999, pp. 992-1000
External fixation is commonly used in the treatment of distal radius fractu
res. In this in vitro study, we investigated changes in fracture stability
when using supplemental radial styloid pinning in combination with external
fixation. Eight previously frozen cadaveric upper extremities were mounted
in a computer-controlled wrist-loading apparatus. This device was used to
generate finger and forearm motions through loading relevant tendons. An un
stable extra-articular distal radius fracture was simulated by removing a d
orsal wedge from the distal radius melaphysis. An electromagnetic tracking
system measured fragment motion following randomized application of a Hoffm
an external fixator, a Hoffman external fixator with 2 supplemental radial
styloid pins, and a dorsal 3.5-mm AO plate. Regardless of the fixation tech
nique used in this unstable fracture model, fragment motion occurred when p
ostoperative finger and forearm motions were simulated. The addition of rad
ial styloid pins to a construct stabilized by an external fixator significa
ntly improved fragment stability, approaching that achieved with the dorsal
AO plate. (J Hand Surg 1999;24A:992-1000. Copyright (C) 1999 by the Americ
an Society for Surgery of the Hand.)