Summary
The purpose of this paper is to describe two uncommon radiographic findings related
to the use of interlocking nails (ILNs) fixation. The first one is a radiolucency
located around the distal tip of the nail observed in three clinical cases. This radiographic
sign was similar to one described in human medicine known as “windshield-wiper effect”
and observed around the tip of the screw used for slipped capital femoral epiphysis
in children, and also in association with intramedullary nail treatment. In one of
our clinical cases, the radiolucency observed four weeks post-surgery completely disappeared
two months later, unfortunately a follow-up radiograph was not available in the two
other cases. The second complication is related to three screw-bendings observed in
the centre of the nail in two clinical cases. In one case both proximal screws appeared
to be radiographically bent, and non-union of the fracture was observed five months
after surgery. The screws were in fact broken, instead of being bent, which we were
able to determine in the second surgery. In the other clinical case, the screw appeared
to be radiographically bent, but the fracture had healed. We could not confirm whether
the screw was bent or broken because the owner refused to permit removal of the implant.
When bone healing complications are detected, bent screws should be checked and suspected
of being broken.
Keywords
Interlocking nail - windshield-wiper effect - implant failure
