Revision pedicle screws with impaction bone grafting: a case series

Background: Pedicle screw fixation in spinal constructs can be subject to failure requiring revision surgery. In cases of aseptic loosening various salvage techniques have been described. Revision screws augmented with cement have become popular but are not without risks. Larger diameter screws are often used but result in reducing bone stock or expanding the pedicles. We present a novel technique of pedicle screw revision by impaction bone allografting and a case series.

Methods: The failed screws are removed. The screw track is probed to check its integrity. Milled bone allograft is funneled into the screw hole and sequentially impacted, before insertion of a replacement screw. We report a case series and describe a single case where this method has been used. Information was gathered from the electronic patient record in our hospital.

Results: Ten screws were revised in 7 patients. Mean age at first surgery was 60.86 (48-76) years. Average time between first surgery and revision was 12.6 (4.7-49.9) months. Average follow-up was 26.2 (5.7-62.2) months and no screws showed any signs of loosening.

Conclusions: Impaction grafting with bone allograft is a technique for pedicle screw salvage that can be used safely and effectively as an alternative to cemented screws, when pedicle screws have failed by aseptic loosening. It avoids the risks associated with cemented screws and in our series was successful.