S1 Pedicle Screw Loosening: A Systematic Review and Meta-Analysis of Risk Factors and Outcomes

Area of Science:

• Spine surgery
• Orthopedic surgery
• Biomedical engineering

Background:

• S1 pedicle screw loosening is a frequent complication in lumbosacral fusion for degenerative conditions.
• This complication can lead to fusion failure, adjacent segment disease, and necessitate revision surgeries.
• The incidence and predictors of S1 pedicle screw loosening require further investigation.

Purpose of the Study:

• To systematically review and meta-analyze the incidence of S1 pedicle screw loosening.
• To identify risk factors associated with S1 pedicle screw loosening in sacral fixation.
• To provide evidence for optimizing surgical planning and fixation techniques.

Main Methods:

• Systematic review and meta-analysis of studies from PubMed and OVID.
• Inclusion criteria: adults undergoing lumbar fusion with S1 sacral fixation, minimum 12-month follow-up, radiographic screw loosening.
• Data extraction included patient demographics, surgical factors, and complication rates.

Main Results:

• 21 studies comprising 2598 patients were included.
• The overall patient screw loosening rate was 23.8%, with pooled proportion at 27%.
• The pooled proportion of individual S1 pedicle screws loosening was 10%.

Conclusions:

• S1 pedicle screw loosening is a significant complication with a 23.8% aggregate rate.
• This complication is linked to pseudarthrosis and adjacent segment disease, affecting patient outcomes.
• Personalized surgical planning, considering bone mineral density and vertebral bone quality, is essential.