METHODS: We undertook an international, prospective study of 15,103 patients ≥45 years of age who had inpatient noncardiac surgery; 3,092 underwent orthopaedic surgery. Non-high-sensitivity TnT assays were performed on postoperative days 0, 1, 2, and 3. Among orthopaedic patients, we determined (1) the prognostic relevance of the MINS diagnostic criteria, (2) the 30-day mortality rate for those with and without MINS, and (3) the probable proportion of MINS cases that would go undetected without troponin monitoring because of a lack of an ischemic symptom.
RESULTS: Three hundred and sixty-seven orthopaedic patients (11.9%) had MINS. MINS was associated independently with 30-day mortality including among those who had had orthopaedic surgery. Orthopaedic patients without and with MINS had a 30-day mortality rate of 1.0% and 9.8%, respectively (odds ratio [OR], 11.28; 95% confidence interval [CI], 6.72 to 18.92). The 30-day mortality rate was increased for patients with MINS who had an ischemic feature (i.e., symptoms, or evidence of ischemia on electrocardiography or imaging) (OR, 18.25; 95% CI, 10.06 to 33.10) and for those who did not have an ischemic feature (OR, 7.35; 95% CI, 3.37 to 16.01). The proportion of orthopaedic patients with MINS who were asymptomatic and in whom the myocardial injury would have probably gone undetected without TnT monitoring was 81.3% (95% CI, 76.3% to 85.4%).
CONCLUSIONS: One in 8 orthopaedic patients in our study had MINS, and MINS was associated with a higher mortality rate regardless of symptoms. Troponin levels should be measured after surgery in at-risk patients because most MINS cases (>80%) are asymptomatic and would go undetected without routine measurements.
LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.
METHODS: Two hundred and twenty sets of radiographs of the spine and the left hand and wrist of patients with idiopathic scoliosis were assessed for skeletal maturity and reliability testing. Risser staging, Sanders staging (SS), distal radius and ulna (DRU) classification, the proximal humeral ossification system (PHOS), and the novel proximal femur maturity index (PFMI) were used. The PFMI was newly developed on the basis of the radiographic appearances of the femoral head, greater trochanter, and triradiate cartilage. It consists of 7 grades (0 to 6) associated with increasing skeletal maturity. The PFMI was evaluated through its relationship with pubertal growth (i.e., the rate of changes of standing and sitting body height [BH] and arm span [AS]) and with established skeletal maturity indices. Longitudinal growth data and 780 corresponding spine radiographs were assessed to detect peak growth using receiver operating characteristic (ROC) curve analysis.
RESULTS: The PFMI was found to be correlated with chronological age (τb = 0.522), growth rates based on standing BH (τb = -0.303), and AS (τb = -0.266) (p < 0.001 for all). The largest growth rate occurred at PFMI grade 3, with mean standing BH growth rates (and standard deviations) of 0.79 ± 0.44 cm/month for girls and 1.06 ± 0.67 cm/mo for boys. Growth rates of 0.12 ± 0.23 cm/mo (girls) and 0 ± 0 cm/mo (boys) occurred at PFMI grade 6, indicating growth cessation. Strong correlations were found between PFMI gradings and Risser staging (τb = 0.743 and 0.774 for girls and boys), Sanders staging (τb = 0.722 and 0.736, respectively), and radius (τb = 0.792 and 0.820) and ulnar gradings (τb = 0.777 and 0.821), and moderate correlations were found with PHOS stages (τb = 0.613 and 0.675) (p < 0.001 for all). PFMI gradings corresponded to as young as SS1, R4, U1, and PHOS stage 1. Fair to excellent interrater and intrarater reliabilities were observed. PFMI grade 3 was most prevalent and predictive for peak growth based on ROC results.
CONCLUSIONS: The PFMI demonstrated clear pubertal growth phases with satisfactory reliability. Grade 3 indicates peak growth and grade 6 indicates growth cessation.
CLINICAL RELEVANCE: The use of PFMI can benefit patients by avoiding additional radiation in skeletal maturity assessment and can impact current clinical protocol of patient visits. PFMI gradings had strong correlations with SS, DRU gradings, and Risser staging, and they cross-referenced to their established grades at peak growth and growth cessation. PFMI may aid in clinical decision making.