Diagnostic Accuracy of Thresholds Less Than or Equal to 8âmA in Pedicle Screw Testing During Lumbar Spine Procedures to Predict New Postoperative Lower Extremity Neurological Deficits.
Spine (Phila Pa 1976)
; 46(2): E139-E145, 2021 Jan 15.
Article
em En
| MEDLINE
| ID: mdl-33347093
ABSTRACT
STUDY DESIGN:
Retrospective observational study.OBJECTIVE:
It has been shown that pedicle screw stimulation thresholds less than or equal to 8âmA yield a very high diagnostic accuracy of detecting misplaced screws in spinal surgery. In our study, we determined clinical implications of low stimulation thresholds. SUMMARY OF BACKGROUND DATA Posterior lumbar spinal fusions (PSF), using pedicle screws, are performed to treat many spinal pathologies, but misplaced pedicle screws can result in new postoperative neurological deficits.METHODS:
Patients with pedicle screw stimulation testing who underwent PSF between 2010 and 2012 at the University of Pittsburgh Medical Center (UPMC) were included in the study. We evaluated the sensitivity, specificity, and diagnostic odds ratio (DOR) to determine how effectively low pedicle screw responses predict new postoperative lower extremity neurological deficits.RESULTS:
One thousand one hundred seventy nine eligible patients underwent 8584 pedicle screw stimulations with lower extremity somatosensory evoked potentials (LE SSEP) monitoring for lumbar fusion surgery. One hundred twenty one of these patients had 187 pedicle screws with a stimulation response at a threshold less than or equal to 8âmA. Smoking had a significant correlation to pedicle screw stimulation less than or equal to 8âmA (Pâ=â0.012). A threshold of less than or equal to 8âmA had a sensitivity/specificity of 0.32/0.90 with DOR of 4.34 [1.83, 10.27] and an area under the ROC curve (AUC) of 0.61 [0.49, 0.74]. Patients with screw thresholds less than or equal to 8âmA and abnormal baselines had a DOR of 9.8 [95% CI 2.13-45.17] and an AUC of 0.73 [95% CI 0.50-0.95].CONCLUSION:
Patients with pedicle screw stimulation thresholds less than or equal to 8âmA are 4.34 times more likely to have neurological clinical manifestations. Smoking and LE deficits were shown to be significantly correlated with pedicle screw stimulation thresholds less than or equal to 8âmA. Low stimulation thresholds result in a high specificity of 90%. Pedicle screw stimulation less than or equal to 8âmA can serve as an accurate rule in test for postoperative neurological deficit, warranting reevaluation of screw placement and/or replacement intraoperatively.Level of Evidence 3.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fusão Vertebral
/
Parafusos Pediculares
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Região Lombossacral
Tipo de estudo:
Diagnostic_studies
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Observational_studies
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Prognostic_studies
/
Risk_factors_studies
Limite:
Adolescent
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Adult
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Aged
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Aged80
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article