Distal volar radial plates: how anatomical are they?

BACKGROUND

Fractures of the distal radius are common, with volar locking plates being increasingly used in their treatment. They aim to provide stable internal fixation and are designed to mirror the natural anatomy. Current volar plate designs incorporate a volar cortical angle (VCA) of 25 degrees.

HYPOTHESIS

The aim of this study is to determine whether the VCA in uninjured distal radii corresponds accurately with modern volar plate designs.

MATERIALS AND METHODS

A retrospective radiological analysis utilizing Computed Tomography scans to assess the VCA of 100 distal radii. Each distal radius was subjected to 3 measurements of the VCA in the sagittal plane.

RESULTS

One hundred patients were identified (67 male, 33 female; mean age 37.4 years). The mean VCA was 32.9 degrees (S.D.±5.14 degrees). The VCA in male patients was significantly greater than in females (33.6 vs 31.5 degrees; P=0.04). There was a statistically significant difference between the lateral VCA and medial VCA (32.2 vs 34.3 degrees, P=0.02).

DISCUSSION

Our study clearly demonstrates that the VCA measured in the distal radius is significantly greater than the volar angulation incorporated within modern plate design. Given that the aim of ORIF is to anatomically reconstruct the distal radius, our study highlights that this may not be possible with current plates.

LEVELS OF EVIDENCE

Level IV Retrospective case series.