Pedicle XXXX : a clinically relevant complication?

@entity3604 @entity1 @entity79 @entity1349
PURPOSE: Literature studies showed a very wide range of pedicle @entity1349 rates after thoracolumbar stabilization, ranging from less than 1 to 15  % in non- @entity3604 @entity1 treated with rigid systems and even higher in @entity3604 subjects or @entity1 treated with dynamic systems. Firstly, this paper aims to investigate how much this complication is affecting the success rate of pedicle screw fixation, in both non- @entity3604 and @entity3604 @entity1 , and to discuss the biomechanical reasons which may be related to the variability of the rates found in the literature. The secondary aim was to summarize and discuss the published definitions and conventions about @entity1349 from a clinical and radiological point of view. METHODS: Narrative literature review. RESULTS: Screw loosening appears to be a minor problem for fixation and fusion of healthy, @entity79 . Pedicle screw fixation in @entity3604 bone is believed to be at risk of loosening, but clinical data are actually scarce. Both expandable and augmented screws may be a viable option to reduce the risk of loosening, but clinical evidence is missing. Posterior motion-preserving implants seems to have a significant risk of @entity1349 . Standardization appears to be lacking regarding the radiological assessment. Marked differences in the loosening rates found based either on planar radiography or on CT scanning were observed. CONCLUSIONS: Reported loosening rates primarily depended on the protocol used for the clinical examination during follow-up and on the conventions used for the radiological assessment. Aiming to a better comparability of published data, we recommend the authors of clinical studies to describe which criteria were used to assess a loosened screw, as well as the protocol of the clinical follow-up examination. Low-dose CT should be used for the assessment of @entity1349 whenever possible.
