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To elucidate the effect of medial meniscus posterior root (MMPR) repair during opening-wedge high tibial osteotomy (OWHTO) in terms of contact pressure (CP) and contact area (CA). Nine fresh-frozen human cadaveric knee specimens were included. Each specimen was tested under 9 conditions comprising 3 different degrees of correction during OWHTO (neutral, 5° of valgus, and 10° of valgus) and 3 different types of MMPR conditions (intact, torn, and repaired). The prepared specimens were attached to a customized tibiofemoral jig in a fully extended state. The CP and CA generated by a tibiofemoral axial load of 650 N was recorded using the Tekscan sensor's pressure mapping software. Statistical analysis was performed using a repeated measures analysis of variance. The increased CP and decreased CA in torn MMPR was decreased and increased, respectively, to the intact MMPR after repairing, irrespective of whether OWHTO was performed. The mean CP at a correction angle of 5° of valgus was 0.4067 ± 0.0768 MPa for intact MMPR, which increased to 0.7340 ± 0.1593 MPa for the torn MMPR and decreased to 0.3614 ± 0.0639 MPa for the repaired MMPR. In addition, the proportion of decrease in CP and increase in CA after MMPR repair was constant, compared with the torn MMPR, irrespective of the degree of correction during OWHTO. MMPR repair decreases CP and increases CA, irrespective of whether OWHTO is performed. The biomechanical advantage of repairing torn MMPR is maintained, regardless of the degree of correction during OWHTO. Both OWHTO and MMPR repair are known to protect the medial compartment of the knee. However, there are concerns in performing 2 procedures simultaneously. Results of our study showed that concurrent repair of the MMPR during OWHTO is useful for protecting the medial compartment of the knee with respect to tibiofemoral contact biomechanics. [ABSTRACT FROM AUTHOR]

• The spinal degenerative changes gradually exacerbate the spinal alignment. • Frailty could be an important factor that influences spinal alignment in the elderly. • Frailty mainly affected lumbo-pelvic alignment, and consequently affected whole spine. The degenerative changes in the spine of the frail elderly gradually exacerbate the alignment of the spine as the degeneration progresses. This study was conducted to assess the relationship between frailty and spine sagittal alignment measured in terms of global, cervical, thoracic, and lumbo-pelvic parameters. In total, 101 patients aged 75 years and older hospitalized for spine surgery were prospectively enrolled. We evaluated spinal sagittal parameters by dividing them into global (C7 sagittal vertical axis [SVA] and T1 pelvic angle [T1PA]), cervical (the C2-7 Cobb angle, Jackson line, and C2-7 plumb line), thoracic (thoracic kyphosis [TK]), and lumbo-pelvic (pelvic tilt [PT] and pelvic incidence minus lumbar lordosis value [PI-LL]). Patient characteristics; the Fatigue, Resistance, Ambulation, Illness, Loss of Weight (FRAIL) scale; and sagittal spinal parameters were included in the analysis. Multiple regression analysis was performed to identify associations between the FRAIL scale and sagittal spinal parameters. The FRAIL scale showed correlations with global sagittal parameters (C7 SVA [β = 0.225, p = 0.029] and T1PA [β = 0.273, p = 0.008]) and lumbo-pelvic parameters (PT [β = 0.294, p = 0.004] and PI-LL [β = 0.323, p = 0.001). Cervical and thoracic parameters were not directly associated with the FRAIL scale. LL and PI-LL were associated with TK, and TK was associated with cervical parameters (the C2-7 Cobb angle, Jackson line and C2-7 plumb line). In conclusion, frailty status could be an important factor that influences sagittal spinal alignment in the elderly. In this study, it was found that frailty mainly affected the balance of lumbo-pelvic alignment, and consequently affected the balance of the whole spine. [ABSTRACT FROM AUTHOR]

Background: We sought to determine whether administrations of intravenous (IV) dexamethasone jeopardize blood glycemic control, increase rates of postoperative complications, and diabetic medication change after TKA.Methods: This retrospective study included 427 patients with DM who underwent TKA. Patients were divided into two groups according to the use of IV dexamethasone (Dexa and No Dexa). For the Dexa, IV dexamethasone (5mg) was administered twice (surgery day, postoperative day 1). Blood glucose level until postoperative day 5, whether the mean blood glucose level was ≥200 mg/dL or not, the rate of a diabetic medication change, and postoperative complications (surgical site infection, delayed wound healing) were analyzed.Results: The adverse effects of IV dexamethasone on glycemic control were limited to the day of injection. The mean blood glucose level was 168.8 mg/dL and 204.4 mg/dL on operation day and 193.0 mg/dL and 210.5 mg/dL on postoperative day 1 in the No Dexa and the Dexa, respectively. High preoperative glycated hemoglobin (HbA1c) levels, but not IV dexamethasone administration, increased the risk of postoperative blood glucose level ≥200 mg/dL (odds ratio [OR], 2.810) and diabetic medication change (OR, 3.635, P < .001). A preoperative HbA1c level of >7.05% was associated with the risk of diabetic medication change. There was increase of postoperative complications (OR, 0.693, P = .552).Conclusions: IV dexamethasone have transient effects on increasing the blood glucose level after TKA in patients with DM. However, patients with a preoperative HbA1c level of ≥7.05% may need to change their diabetic medication after TKA, regardless of IV dexamethasone administration. [ABSTRACT FROM AUTHOR]

• Both LF and LP demonstrated improvement in neurologic outcome for patients with multilevel cervical OPLL. • There was no difference in reoperation rate between the two surgical methods. • Complication rates including C5 palsy were higher in LF patients than LP patients. Laminectomy with instrumented fusion (LF) has demonstrated better prevention of ossification of posterior longitudinal ligament (OPLL) growth compared to laminoplasty (LP). There remains uncertainty, however, as to which surgical approach is more beneficial with respect to clinical outcomes and complications. We retrospectively reviewed 273 cervical OPLL patients of more than 3 levels, from the two institutions' databases, who underwent LF or LP between January 1998 and January 2016. Each 273 patient (85 with LF, 188 with LP) was assessed for postoperative neurologic and radiologic outcomes, complications and reoperations. The mean length of follow-up was 40.11 months. There were baseline differences between cohorts. Overall, postoperative JOA recovery rate at last follow up was significantly better in the LP group with similar improvement in visual analog neck score. Postoperative C2-7 Cobb angle was decreased compared to baseline for both LF and LP cohorts, but there was no significant difference between groups. Complications occurred in 19 (22.35%) LF patients, and 11 (5.85%) LP patients, with higher incidence of C5 palsy and instrumentation failure in the LF group. Four LF patients (4.71%) and five LP patients (2.66%) underwent reoperation during the follow up period. [ABSTRACT FROM AUTHOR]

Repetitive heating and cooling cycles inevitably cause crack damage of hot gas components of gas turbine engines, such as blades and vanes. In this study the self-healing capacity is investigated of mullite + ytterbium monosilicate (Yb 2 SiO 5) as EBC material with Ti 2 AlC MAX phase particles embedded as a crack-healing agent. The effect of Ti 2 AlC in the EBC was compared with the self-healing ability of the mullite + Yb 2 SiO 5 material. After introducing cracks by Vickers indentation on the surface of each sample, crack healing was realized by controlling the temperature and time during the post-heat-treatment process. For the mullite + Yb 2 SiO 5 composite with Ti 2 AlC particles, crack healing occurred at 1000 °C, while in the case of the mullite + Yb 2 SiO 5 composite without Ti 2 AlC, a sustained temperature of 1300 °C or higher was required. Compared with the healing of the mullite + Yb 2 SiO 5 composite by the formation of a eutectic phase, the addition of Ti 2 AlC promoted healing via the oxidation of Ti and Al. Notably, the surface formation of a ternary oxide of Ti–Yb–O was confirmed, which completely covered the damage area. Consequently, the addition of a Ti 2 AlC MAX phase to the EBC composite resulted in a complete strength recovery, while the mullite + Yb 2 SiO 5 composite without Ti 2 AlC showed a strength recovery of about 80%. Furthermore, by analyzing the indentation load–displacement curve to indicate the role of Ti 2 AlC, the addition of Ti 2 AlC improved both the hardness and stiffness of the composite. [ABSTRACT FROM AUTHOR]

Aims: The prognosis of patients with chronic kidney disease (CKD) and intertrochanteric fractures is unclear. This study was aimed to analyze the mortality and complication rates among CKD patients with intertrochanteric femoral fractures and the risk factors of one-year mortality after surgery.Patients and Methods: This retrospective cohort study included 49 patients diagnosed with grades III, IV, or V CKD who were surgically treated for an intertrochanteric fracture between January 2011 and February 2019 at a tertiary university hospital. Preoperative parameters, including age, gender, bone mineral density, follow-up period (mean: 8.6 months range: 1~82 months), underlying disease, American Society of Anesthesiologists classification, fracture classification, and grade of CKD were identified, and complications and mortality rates after surgery were examined. The patients were divided into two groups according to whether one-year mortality after surgery had occurred or not, and a logistic regression analysis was performed to analyze the risk factors of mortality.Results: Of the 49 total patients, 16 died <1 year postoperatively. Pneumonia (n = 11) was the most common postoperative complication. Twenty-one patients died during the follow-up period. Significant differences in gender (p = 0.006) and grade of CKD (p = 0.022) distributions were found between the two groups, divided according to whether one-year mortality had occurred or not. In a univariate analysis, CKD grade and postoperative septic shock were highly associated with one-year mortality. In a multivariate analysis, septic shock, acute kidney injury, and CKD grade were identified as the risk factors of one-year mortality.Conclusion: The mortality and complication rates were high among the CKD patients with intertrochanteric fractures. Grades of CKD significantly correlated with one-year mortality after surgery; therefore, they and an important factor that must be considered when developing a strategy to improve the postoperative survival rate of patients with CKD. [ABSTRACT FROM AUTHOR]