Background: Variations among methods to measure glenoid version have created uncertainty regarding which method provides the most consistent measurements of morphology. Greater deformity may also make accurate depiction of the native morphology more challenging. This study examined 4 current methods (Friedman, corrected Friedman, Ganapathi-Iannotti, and Matsumura) and an experimental scapular border-derived coordinate system method, to compare measurement inconsistencies between methods and reference systems and assess the impact of glenoid deformity on measured glenoid version. Methods: Three-dimensional scapulae were created from computed tomography (CT) scans of 74 shoulders that had undergone arthroplasty (28 A2, 22 B2, 10 B3, and 14 C glenoids) and 34 shoulders that had not undergone arthroplasty. Glenoid version measurements were made in Mimics using the 4 methods. For the experimental method, scapulae were reconstructed, and 3 orthogonal global coordinate planes (GCPs) were derived from the medial and lateral borders. Version was measured as the angle between the sagittal reference plane and an anterior-posterior glenoid vector. The intraclass correlation coefficient (ICC) was calculated for the Friedman and corrected Friedman methods. Inconsistencies were assessed for all methods using the interquartile range, mean and standard deviation, and repeated-measures analysis of variance. Concordance correlation coefficients (CCCs) were calculated to assess agreement among the methods. Results: Scapular plane-based methods (experimental, Friedman, and corrected Friedman) yielded an average version between −10° and −12°, with average measurement differences among these methods of <2°. Vault methods (Ganapathi-Iannotti and Matsumura) overestimated or underestimated version by an average of 5° to 7° compared with scapular plane-based methods, and showed significant differences of >12° when compared with each other. Scapular plane-based methods maintained consistency with increasing deformity. Conclusions: The other methods of version measurement using the scapular planes as the reference were highly comparable with the corrected Friedman method. However, when the reference plane was the glenoid vault, version measurements were inconsistent with scapular plane-based methods, which is attributed to differences in the reference systems. In surgical planning, the coordinate system utilized will impact version measurements, which can result in variations in the planned surgical solutions. Additionally, as glenoid deformity increases, this variation resulting from the utilization of different coordinate systems is magnified.

Study Design. A retrospective, propensity-matched observational study. Objective. To assess the impact of cell saver (CS) homologous transfusion on perioperative medical complications in adult patients undergoing spinal deformity surgery. Summary of Background Data. Despite many endorsing its use, many analyses still refute the efficacy of CS on decreasing total perioperative allogenic red blood cell transfusions, cost efficiency, and its effect on perioperative complications. Methods. Adult patients who underwent spinal deformity surgery at a single center between 2015 and 2021 were retrospectively reviewed. Patient-specific, operative, radiographic, and 30-day complications/readmission data were collected for further analysis. Two methods were utilized to test our hypothesis: (1) absolute threshold model: two cohorts created among patients who received ≥550 mL of CS intraoperatively and those who received less; (2) adjusted ratio model: two cohorts created dependent on the ratio of CS to estimated blood loss (EBL). Propensity-score matching and various statistical tests were utilized to test the association between CS and perioperative medical complications. Results. Two hundred seventy-eight patients were included in this analysis with a mean age of 61.3±15.7yrs and 67.6% being female. Using the first method, 73 patients received ≥550 mL of CS, and 205 received less. Propensity-score matching resulted in 28 pairs of patients. 39.3% of patients with ≥550 mL CS required readmission within 30 days compared with 3.57% of patients in the <550 mL cohort (P=0.016), despite a nearly identical proportion of patients requiring intraoperative blood transfusions (P>0.9999). Using the second method, 155 patients had CS/EBL<0.33 and 123 with CS/EBL ≥0.33. 5.16% and 21.9% among patients with CS/EBL<0.33 and CS/EBL≥0.33, respectively, were readmitted by the 30-day marker (P<0.0001). Conclusions. Our findings indicate that greater CS volumes transfused are associated with higher rates of 30-day readmissions. Thus, surgeons should consider limiting CS volume intraoperatively to 550 mL and when greater volumes are required or preferred, ensuring that the ratio of CS:EBL remains under 0.33.

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