Abstract
Background Dorsal bridge plate fixation is an effective technique for stabilization of highly
comminuted, complex distal radius fractures. However, it is unknown whether fixation
to the second or third metacarpal is optimal. Given dorsal bridge plating spans the
radiocarpal joint, it is unclear if the dorsal spanning plate affects carpal position.
This study investigates differences in carpal translocation resulting from bridge
plate distal fixation to either the second or third metacarpal.
Methods Ten paired cadaveric upper extremities without evidence of gross deformity or prior
surgery distal to the elbow were evaluated with three-view wrist fluoroscopic images
for baseline radiographic measurements. An unstable distal radius fracture model was
created via a volar approach using a 1-cm osteotomy. Following fracture creation,
a dorsal bridge plate was applied with random to the second metacarpal on one limb,
and the third metacarpal on the contralateral limb. Laterality for distal fixation
was chosen randomly. Fluoroscopic images were repeated and radial inclination, radial
height, radiocarpal angle, volar tilt, ulnar variance, radiolunate angle, radioscaphoid
angle, radial rotation index, and carpal translocation were measured.
Results Radial inclination, radial height, radiocarpal angle, volar tilt, ulnar variance,
radiolunate angle, and radioscaphoid angle were not statistically different before
and after fixation, or when comparing the second or third metacarpal fixation. Additionally,
there was no difference in Taleisnik's ulnar translocation index, Chamay's ulnar translation
index, or McMurtry's carpal translation index based on which metacarpal was used for
distal fixation.
Conclusions Dorsal bridge plate fixation of distal radius fractures restores preoperative physiologic
measures of the radius, ulna, and carpus. Carpal translocation was similar when comparing
distal fixation to the second or third metacarpal in distal radius fractures stabilized
with a bridge plate.
Level of Evidence This is a Level V, therapeutic study.
Keywords
distal radius fracture - bridge plate - radiocarpal distraction plate - carpal translocation
- cadaveric study
