Radiomics in the prediction of metal work failure in thoracolumbar spine fixations.

STUDY

DESIGN

Retrospective Cohort Study

Objectives

To identify factors that could predict metalwork failure in thoracolumbar instrumentation for different indications.

METHODS

A retrospective analysis was conducted on patients who underwent thoracolumbar fixation in a single unit between January 2014 to January 2023. Radiological parameters were measured using CT and MRI. The study was analysed in a per-case and a per-screw basis using T-test, Chi-Square test, Logistic regression and ROC analysis.

RESULTS

Over a 9-year period, 444 patients underwent 486 thoracolumbar instrumentation surgeries. Complications were observed in 20% of cases, with post-operative wound infection being the most common (9.7%). Metalwork failure was identified in 31 cases (6.38%). In the per-patient analysis, the presence of wound infection and average pedicle cancellous bone density (<280 HU), were statistically significant factors in predicting metalwork failure. Wound infection was a significant predictor for metal work failure in both degenerative and traumatic indications for spinal fixations. In the per-screw analysis, the screw-to-pedicle area ratio was significantly higher (>0.21) in screws without metalwork failure. For traumatic indications, the screw-to-pedicle area ratio (<0.25) and Charleston Comorbidity Index (CCI) (>0.15) were significant predictors. For degenerative indications, presence of wound infection and total pedicle bone density (<220 HU) were significant predictors. For neoplastic indications, only age (>66 years) was a predictor.

CONCLUSION

This study highlights the significance of avoiding post-operative wound infection, the use of screws with a larger diameter and higher pedicle cancellous bone density (>280 HU) in the reducing the risk of metalwork failure in thoracolumbar fixation.