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The mechanisms underlying sex differences in response to stress are unclear. Here, the authors show that meningeal lymphatics dysfunction modulates the sex difference in the stress susceptibility to depression- and anxiety-like behaviours in mice.

Abstract. Background. During cup implantation, vertical height of the cup center (V-HCC) should be precisely controlled to achieve sufficient bone-cup coverage (BCC). Our study aimed to investigate the acetabular bone stock and the quantitative relationship between V-HCC and BCC in Crowe types I to III hips. Methods. From November 2013 to March 2016, pelvic models of 51 patients (61 hips) with hip dysplasia were retrospectively reconstructed using a computer software. Acetabular height and doom thickness were measured on the mid-acetabular coronal cross section. V-HCC was defined as the vertical distance of cup rotational center to the interteardrop line (ITL). In the cup implantation simulation, the cup was placed at the initial preset position, with a V-HCC of 15 mm, and moved proximally by 3-mm increments. At each level, the BCC was automatically calculated by computer. Analysis of variance and Kruskal-Wallis test were used to compare the differences between groups. Results. There were no significant between-group differences in maximum thickness of the acetabular doom; however, peak bone stock values were obtained at heights of 41.63 ± 5.14 mm (Crowe type I), 47.58 ± 4.10 mm (Crowe type II), and 55.78 ± 3.64 mm (Crowe type III) above the ITL. At 15 mm of V-HCC, median BCC was 78% (75–83%) (Crowe type I), 74% (66–71%) (Crowe type II), and 61% (57–68%) (Crowe type III). To achieve 80% of the BCC, the median V-HCC was 16.27 (15.00–16.93) mm, 18.19 (15.01–21.53) mm, and 24.13 (21.02–28.70) mm for Crowe types I, II, and III hips, respectively. Conclusion. During acetabular reconstruction, slightly superior placement with V-HCC

Purpose: To compare the postoperative survival and mortality rates in intertrochanteric femoral fracture (IFF) patients who underwent either open reduction internal fixation (ORIF) or hip arthroplasty. Methods: Clinical data from senior patients who had IFF and underwent ORIF or hip arthroplasty were analyzed retrospectively. Survival curves were compared between groups with Kaplan–Meier method and log-rank test. Significant independent prognostic factors were identified by Cox multivariate regression analysis. Results: All patients recovered fully post-surgery. Although 31 patients died during the follow-up period (ORIF, mean 45.4 months; arthroplasty, mean 51.6 months), mortality rate did not differ significantly between the groups. The 1-yr and 2-yr survival rate estimates for the ORIF group were 92.2%, and 86%, respectively; they were 85% and 74% for the arthroplasty group. Average survival lengths for ORIF and arthroplasty groups were 88 and 67 months, respectively. The effect of surgical approaches on survival differed significantly (log-rank test c2 = 6.402, p = 0.011). Multivariate Cox regression model indicated that surgical choice (p = 0.036) was a significant independent risk factor for the prognosis of senile IFF, even with adjustment for age (p = 0.002). Conclusion: The overall postoperative prognosis was superior in senile IFF patients treated with ORIF.

Background: Accurate evaluation of the plain radiography of lower limb is critical for preoperative planning of total knee arthroplasty (TKA). We aimed to investigate the effect of femoral lateral bowing and rotation on the radiographic measurements of distal femoral condyle resection thickness (DRT) and the distal femoral resection valgus angle (FVA). Methods: We analyzed 246 three-dimensional femoral models generated from computed tomography images of 123 patients, acquiring projected contours in seven positions – 20° and 10° internal rotation; 0° rotation; 10°, 20°, 30°, and 40° external rotation – for each model. Medial and lateral condyle DRTs, femoral shaft lateral bowing angle (FBA), and distal FVA were determined for each position. Linear mixed effect model was used to determine the effect of degree of femur rotation on repeated measurements of DRT or FVA. Results: FBA significantly affected the FVA and DRT (Pearson's R = 0.767 and −0.408, respectively; P < 0.000). Samples were divided into three groups according to the FBA measured in neutral position: FBA 0° but 3°: DRT 2.22 ± 1.31 mm, FVA 7.37° ± 1.31°. From simulated 20° internal rotation to 40° external rotation in each femoral model, the average variation ranges of radiographically measured DRT, FVA, and FBA were 0.50 ± 0.28 mm, 2.93° ± 0.96°, and 10.33° ± 1.90°, respectively, with no significant differences among the FBA groups. The degree of femoral rotation significantly affected the FVA (F = 62.148, P < 0.000), whereas there was no effect on condyle resection thickness (F = 0.4705, P = 0.494). Conclusions: Axial femoral rotation has less effect on radiographic measurements of differences in the DRT than on those of the distal FVA.

Background: Accuracy of implant placement in total knee arthroplasty (TKA) is crucial. Traditional extramedullary alignment instruments are fairly effective for achieving the desired mean tibial component coronal alignment. We modified the traditional tibial plateau resection technique and evaluated its effect on alignment restoration. Methods: Two hundred and eighty-two primary TKAs in our hospital between January 2013 and December 2014 were enrolled in this retrospective study. Group A consisted of 128 primary TKAs performed by one senior surgeon. Preoperative measurement of the tibial resection was conducted on radiographs, and the measured thicknesses of the lateral and medial plateau resection were used to place the tibial alignment guide. Group B consisted of 154 primary TKAs performed by the other senior surgeon, using a traditional tibial plateau resection technique. In all patients, an extramedullary guide was used for tibial resection, and preoperative and postoperative full-leg standing radiographs were used to assess the hip-knee-ankle angle (HKA), femoral component alignment angle (FA), and tibial component alignment angle (TA). A deviation ≥3° was considered unsatisfactory. Data were analyzed by unpaired Student's t-test. Results: The mean postoperative HKA and TA angles were significantly different between Groups A and B (178.2 ± 3.2° vs. 177.0 ± 3.0°, t = 2.54, P = 0.01; 89.3 ± 1.8° vs. 88.3 ± 2.0°, t = 3.75, P = 0.00, respectively). The mean postoperative FA was 88.9 ± 2.5° in Group A and 88.9 ± 2.6° in Group B, and no significant difference was detected (t = 0.10, P = 0.92). There were 90 (70.3%) limbs with restoration of the mechanical axis to within 3° of neutral alignment and 38 (29.7%) outliers (>3° deviation) in Group A, whereas there were 89 (57.8%) limbs with restoration of the mechanical axis to within 3° of neutral alignment and 65 (42.2%) outliers (>3° deviation) in Group B. The severity of the preoperative alignment deformity was a strong predictor for postoperative alignment. Conclusions: Using conventional surgical instruments, preoperative measurement of resection thickness of the tibial plateau on radiographs could improve the accuracy of conventional surgical techniques.