Table 3

Comparing the ESSG-ISSG calculator with other commonly used risk stratification tools.

Predictive ToolFactors Used to Predict OutcomesMeasured Outcome
ESSG-ISSG calculatorTwelve basic patient demographics: gender, age, height, weight, smoking history, prior spine surgery, heel walk, toe walk, leg weakness, ASA grade, NRS back pain, NRS leg pain
Nine radiographic parameters: major curve location, Cobb angle, coronal balance, leg length discrepancy, L1-S1 angle, pelvic tilt, sacral slope, sagittal balance, global alignment
8 HRQL questions
Nine surgical characteristics: number of stages, use of bone graft, use of antifibrinolytics, number of levels fused, upper instrumented vertebra, lower instrumented vertebra, implant density, posterior rod material, posterior rod diameter
Major complications, reinterventions, readmissions, and patient-reported outcomes including SRS-22, Oswestry Disability Index, SF36v2
Charlson Comorbidity IndexAge, history of MI, CHF, PVD, DM, CKD, CVA/TIA, AIDS, liver disease, connective tissue disease, peptic ulcer disease, hemiplegia, solid tumor, leukemia, lymphomaEstimated 10-y survival based on medical comorbidities
ACS-NSQIP CalculatorAge, BMI, functional status, ASA class
History of HTN, DM, CHF, COPD, acute kidney injury, CKD requiring dialysis, smoking, ascites, sepsis, disseminated cancer
Postoperative risk of any complications, severe complications, cardiac complications, and death
SpineSageT Age, BMI, gender, diagnosis
Level (cervical, thoracic, lumbar),
Approach (anterior, lateral, posterior)
Previous spine surgery, revision surgery, previous cardiac complications
History of CVA/TIA, COPD, asthma, HTN, rheumatoid arthritis, kidney disease, cancer, syncope/seizure, anemia, bleeding disorder, DM, CHF
Expected complication rates after various types of spine surgery
ASAPatients clinically classified into 1 of the following categories based on multiple factors:
I: normal healthy patient
II: mild systemic disease
III: severe systemic disease
IV: severe systemic disease constant threat to life
V: moribund patient not expected to survive without the operation
Preoperative risk of undergoing anesthesia
mFI-5CHF within 30 d of surgery
Partially or totally dependent functional health status at time of surgery
History of DM, COPD or pneumonia, HTN
Occurrence of adverse postoperative outcomes
mFI-11Functional status, history of HTN, DM, MI, PVD, CVD, cerebrovascular disease ± neurologic deficit, impaired sensorium, respiratory problems, other cardiac problemsOccurrence of adverse postoperative outcomes
  • Abbreviations: ASA, American Society of Anesthesiology; BMI, body mass index; CHF, congestive heart failure; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular accident; CVD, cardiovascular disease; DM, diabetes mellitus; ESSG, European Spine Study Group; HTN, hypertension; ISSG, International Spine Study Group; mFI, modified frailty index; MI, myocardial infarction; NRS, numeric rating scale; PVD, peripheral vascular disease; TIA, transient ischemic attack.