Abstract
Background Dart throw motions are frequently used during rehabilitation but the ideal orientation
of a dart throw motion is unknown.
Questions/Purposes The purpose of this study was to measure the axial force on the distal radius during
different dart throw motions with the wrist and forearm in various positions. Our
hypothesis was that there would be a significant difference on the axial force between
various forearm positions and different dart throw orientations.
Methods Eight fresh frozen cadaver wrists were moved through 10 different orientations of
a dart throw motion with the forearm in neutral, in pronation, and during a dynamic
forearm rotation motion while the axial force was measured.
Results Significantly smaller axial force occurred with the forearm in pronation than during
the dynamic forearm motion. The shorter dart throw motions which were oriented equally
toward the flexion/extension and radioulnar deviation axes had significantly smaller
distal radius forces than nearly all of the other dart throw motions.
Conclusion/Clinical Relevance Rehabilitation protocols incorporating a dart throw motion may be of benefit after
injury or surgery. To minimize the axial force transmitted through a healing distal
radius fracture, short dart throw motions, oriented at 45 degrees from the sagittal
and coronal planes, with the forearm in pronation, might be preferable for range of
motion activities during rehabilitation.
Keywords
dart throw motion - distal radius forces
