Parametric study on the production of the GAGG:Ce and LSO:Ce multicomponent oxide scintillator materials through use of a planetary ball mill.

The material presented herein focuses on the exploration of the production of gadolinium aluminum gallium garnet and lutetium oxyorthosilicate doped with cerium (GAGG:Ce and LSO:Ce, respectively) through mechanochemical means. Multiple parameters are explored including mass of starting material, ball size, rotational speed of the mill, number of balls employed, and material used for the milling container. Theoretical calculations were conducted using a pre-established equation and showed that, when all other parameters were held constant, in scenarios where (1) a smaller mass of sample, (2) faster revolutions per minute, (3) greater numbers of balls, or (4) a greater density of the material used for the vials and balls were employed, there should be higher energies imparted to the system. Actual results executed appeared to exhibit somewhat congruent results, but showed limitations due to experimental (non-idealized) conditions.

Predictive factors of hospital length of stay in patients with operatively treated ankle fractures.

BACKGROUND: Operative fixation of ankle fractures is common. However, as reimbursement plans evolve with the potential for bundled payments, it is critical that orthopedic surgeons better understand factors influencing the postoperative length of stay (LOS) in patients undergoing these procedures to negotiate appropriate reimbursement. We sought to identify factors influencing the postoperative LOS in patients with operatively treated ankle fractures. MATERIALS AND METHODS: Six hundred twenty-two patients with ankle fractures between January 1st, 2004 and December 31st, 2010 were identified retrospectively. Charts were reviewed for gender, length of operative procedure, method of fixation, American Society of Anesthesiologists (ASA) physical status score, medical comorbidities, and postoperative LOS. Both univariate and multivariate models were developed to determine predictors of patient LOS. Financial data for an average 24-h inpatient stay were obtained from financial services. RESULTS: Six hundred twenty-two patients were included. In a linear regression analysis, a statistically significant relationship was demonstrated between ASA status and LOS (P < 0.001). Multiple regression analysis further characterized the relationship between ASA and LOS: a 1-U increase in ASA classification conferred a 3.42-day increase in LOS on average (P < 0.001). Based on an average per-day inpatient cost of $4,503, each unit increase in ASA status led to a $15,490 increase in cost. CONCLUSIONS: Our study demonstrates that ASA status is a powerful predictor of LOS in patients undergoing operative fixation of ankle fractures. More complete understanding of these factors will lead to better risk adjustment models for measuring outcomes, determining fair reimbursement, and potential improvements to the efficiency of patient care. LEVEL OF EVIDENCE: Level III retrospective comparative study regressing length of stay with many variables, including ASA physical status.

Ankle radiographs in the early postoperative period: do they matter?

OBJECTIVES: To evaluate the utility of postoperative ankle radiographs via a comparison of complication rates among patients who had ankle radiographs in the early postoperative period versus those who obtained radiographs in a delayed fashion. DESIGN: Retrospective chart review. SETTING: Urban level I trauma center. PATIENTS/PARTICIPANTS: Approximately 1411 patients who underwent surgical fixation of an ankle fracture between 2001 and 2010 who received postoperative ankle radiographs in postoperative days 7-120. INTERVENTION: Patients were identified using a current procedural terminology search and were divided between 2 groups based on the timing of the first postoperative ankle radiograph. Each chart was reviewed for complications. MAIN OUTCOME MEASUREMENTS: The rate of complications for patients with early postoperative ankle radiographs (7-21 days) was compared with those of patients with late postoperative radiographs (22-120 days) using χ and Fisher exact tests. RESULTS: Approximately 889 patients were included in the early group and 522 patients were in the late group. Overall, 93 patients with complications were identified (6.59%): 62 patients (6.97%) in the early group and 31 patients (5.93%) in the late group. The results showed no statistically significant difference in the rate of complications between the early and late groups. CONCLUSIONS: There is insufficient evidence to suggest that complication rates following ankle fracture fixation differ by the timing of postoperative radiographs. This investigation questions the justification of routine radiographs of operatively treated ankle fractures. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.