[Arthroscopic evaluation of tibial plateau fractures combined with meniscal tears and cruciate ligamentous injuries].

Objectives: To investigate the types of meniscal tears and cruciate ligamentous injuries in patients with tibial plateau fracture(TPF) following arthroscopic examination. Methods: The clinical data of 216 patients with TPF who underwent closed reduction and internal fixation (CRIF) from January 2016 to January 2019 at Trauma Emergency center, the Third Hospital of Hebei Medical University were analyzed retrospectively. There were 147 males (147 knees) and 69 females (69 knees),aged 46.3 years (range: 18 to 80 years). All patients underwent closed reduction for the displaced fracture fragment with the use of bidirectional rapid redactor,and minimally invasive percutaneous plate osteosynthesis. Intra-operative arthroscopic examination was performed to exam the stability of meniscus and the continuity of cruciate ligamentous after CRIF. The percentages and types of meniscal tears and cruciate ligamentous injuries were recorded. Results: The overall percentages of meniscal tears associated with TPFs was 48.6%(105/216). The most common pattern of meniscal tears was longitudinal tears, accounting for 43.8% (46/105), and it occurred most frequently in Schatzker type Ⅱ (58.7%, 27/46). Furthermore, the percentage of meniscal complex tears was 17.1% (18/105), occurring most frequently in Schatzker type Ⅴ (9/18). The overall percentage of cruciate ligamentous injuries associated with TPFs was 17.1% (37/216), and the percentages of anterior cruciate ligament (ACL) injuries was 64.9%(24/37), the percentage of posterior cruciate ligament injuries was 35.1%(13/37). Avulsion fracture was the most common pattern in ACL injuries, accounting for 41.7% (13/24), and all occurred in the tibial insertion site. Conclusions: In the present study, the percentages of meniscal tears and ligamentous injuries in TPFs are 48.6% and 17.1%, respectively. The most common types are meniscal longitudinal tears and ACL injury, occurring most frequently in Schatzker type Ⅱ and Ⅳ, respectively. Recognition of concomitant meniscal tears and cruciate ligamentous injuries in TPFs is helpful for trauma physicians to choose the best surgical treatment.

The synergistic effect of grain boundary and grain orientation on micro-mechanical properties of austenitic stainless steel.

Micro/nano-scale deformation behavior including hardness, elastic modulus, and pop-ins, was studied in a medical austenitic stainless steel followed by post-mortem EBSD characterization. Relatively higher hardness and modulus was observed near {101} and more pop-ins occurred in this orientation at high loading rate. The activation volume (v) obtained from nanoindentation had weak dependence on grain orientation and was ~10-20 b3, indicating that neither diffusional creep processes nor conventional dislocation segments passing through dislocation forests controls plastic deformation in our study. The plastic zone radius (c) and the distance of the indent from the grain boundary (d) were used to describe the effect of grain boundary on the pop-in effect. The ratio of c/d meets amplitude version of Gaussian peak function distribution for a given orientation, whose peak value remains nearly constant for all the orientations.

[The clinical efficacy of arthroscopic combined with dual-plane high tibial osteotomy in the treatment of anterior cruciate ligament injury combined with varus deformity of knee joint].

Objective: To explore the short-term effectiveness of arthroscopic combined with dual-plane high tibial osteotomy in the treatment of anterior cruciate ligament injury combined with varus deformity of knee joint. Methods: A retrospective study was performed on 17 patients with anterior cruciate ligament injury combined with varus deformity of knee joint who underwent arthroscopic combined with dual-plane high tibial osteotomy at Department of Bone and Joint, the Affiliated Hospital of Southwest Medical University from January 2017 to June 2018.There were 11 males (11 knees) and 6 females (6 knees), aged 41.3 years (range: 32 to 49 years) .During the surgery, the weight bearing line of lower extremity was set to 62.5% position of the tibial plateau on coronal plane. The tibial slope was adjusted to the normal range on sagittal plane, and anterior cruciate ligament was reconstructed to improve the stability of knee joint.At final follow up, full length weight bearing X ray was used to evaluate the position of weight bearing line, femoral tibial angle and tibial slope pre- and post-operatively.The Lysholm scores, Hospital for Special Surgery score, Tegner knee activity scores and International Knee Documentation Committee (IKDC) scores were used to estimate knee joint function, while the Lachman test, KT-1000 side-to-side difference and pivot-shift test were used to estimate the knee joint stability. Results: The patients were followed up for 1.8 years(range:1.2 to 2.5 years). No complication such as infection, deep vein thrombosis, graft failure, nonunion or delayed union was observed.The weight bearing line was corrected from (28.48±2.24)% preoperatively to (57.43±1.02)% postoperatively (t=46.80, P=0.00) .The femoral tibial angle was improved from (172.31±3.37) ° preoperatively to (178.91±1.34) ° postoperatively(t=10.46, P=0.00). The tibial slope was decreased from (14.29±1.26) ° preoperatively to (9.31±0.79) ° postoperatively (t=24.59, P=0.00) . The KT-1000 side-to-side difference decreased from (7.95±1.19) mm preoperatively to (1.79±0.49)mm postoperatively(t=18.34, P=0.00). At the last follow-up, Lysholm score, Hospital for Special Surgery score, Tegner score, and the IKDC knee evaluation score of patients showed significant improvement from preoperative(P<0.05). Conclusion: Arthroscopic combined with dual-plane high tibial osteotomy can get a good short term efficacy in the treatment of anterior cruciate ligament injury combined with varus deformity of knee joint which can significantly improve the alignment of lower extremity and knee joint stability.

[Chronic stress model in New Zealand white rabbit with hyperlipidemia].

Objective: To establish and evaluate chronic stress model in New Zealand white rabbit with hyperlipidemia. Methods: A total of 45 clearing grade male New Zealand white rabbits were divided into four groups with random number table method: control (CON), normal diet combined with chronic stress for 8 weeks (CON+ CS), high fat diet (HFD) and high fat diet for 4 weeks combined with chronic stress for 8 weeks (HFD+ CS). Both social stress and physical stress methods were adopted.One-way ANOVA was used for comparison among groups. Results: (1) Chronic stress model assessments: ①body weight, the weight gain of stress groups was significantly reduced; ②behavioral assessment, rabbits exposed to stress in CON+ CS and HFD+ CS group [54%±7%, 55%±5%] exhibited more inactivity behavior than CON and HFD group [27%±5.28%, 34%±6%, P<0.01, P<0.05]; ③serum indexes: after stress regime for 4 weeks, cortisol of HFD+ CS was higher than HFD group [(60±5) ng/ml vs (38±4) ng/ml, P=0.001]. After 8 weeks, the serum levels of hs-CRP and IL-6 also elevated. (2) The effect of hyperlipidemia on chronic stress: compared with CON+ CS, HFD+ CS group showed more inactivity behavior and rising levels of cortisol, hs-CRP and IL-6. (3) Blood lipids: chronic stress induced raised serum total cholesterol. Conclusions: (1)Chronic stress model in rabbit with hyperlipidemia could be successfully established with 4-week high lipid feed followed by social stress combined with physical stress for 8 weeks.(2) Hyperlipidemia and chronic stress influences each other.

Activation of ephrinB-EphB receptor signalling in rat spinal cord contributes to maintenance of diabetic neuropathic pain.

BACKGROUND: Diabetic neuropathic pain (DNP) is severe and intractable in clinic. The specific cellular and molecular mechanisms underlying DNP remain elusive and its treatment are limited. We investigated roles of EphB1 receptor in the development of DNP. METHODS: Diabetic neuropathic pain was produced in male, adult, Sprague-Dawley rats by a single i.p. streptozotocin (STZ) or alloxan. Western blot analysis and immunohistochemistry were used to analyse expression of EphB1 receptor as well as the activation of the glial cells and the pro-inflammatory cytokines in the spinal cord. DNP manifested as mechanical allodynia, which was determined by measuring incidence of foot withdrawal in response to mechanical indentation of the hind paw by an electro von Frey filament. RESULTS: Diabetic neuropathic pain and high blood glucose were exhibited simultaneously in around 70% of animals that received i.p. STZ or alloxan. Phosphorylation of EphB1, activation of the astrocytes and microglial cells, and level of tumour necrosis factor (TNF)-α and interleukin (IL)-1ß in the spinal cord were significantly increased in rats with DNP. Spinal blocking EphB1 receptor activation in the late phase after STZ injection significantly suppressed the established mechanical allodynia as well as activation of the astrocytes and microglial cells and activity of TNF-α and IL-1ß. However, spinal treatment of EphB1-Fc in the early phase after STZ injection did not prevent the induction of DNP. CONCLUSIONS: EphB1 receptor activation in the spinal cord is critical to the maintenance, but not induction of diabetic pain. EphB1 receptor may be a potential target for relieving the established diabetic pain. SIGNIFICANCE: Activation of EphB1 receptor in the spinal cord is critical to maintaining the established diabetic neuropathic pain, but not to diabetic pain induction. Spinal blocking EphB1 receptor activation suppresses ongoing diabetic neuropathic pain.

Is population bone mineral density variation linked to the marker D11S987 on chromosome 11q12-13?

Our purpose is to test linkage of human chromosome 11q12-13 to BMD variation. Chromosome 11q12-13 has been linked to three BMD-related phenotypes that are inherited as Mendelian traits in human pedigrees: an autosomal dominant high bone mass trait, autosomal recessive osteoporosis pseudoglioma, and autosomal recessive osteopetrosis. A sibling pair study with 374 sibships showed significant linkage of D11S987 to normal BMD variation, with a maximum logarithm of odds score of 3.5. However, a subsequent linkage study with a total of 595 sibling pairs demonstrated reduced significance for linkage of D11S987 to bone mineral density variation, with a logarithm of odds score less than 2.2. We genotyped five markers in a genomic region of approximately 27 cM centering on D11S987 and measured bone mineral density and other traits (weight, etc.) for 635 individuals from 53 human pedigrees. Each of these pedigrees was ascertained through a proband with bone mineral density Z-scores less than -1.28 at the hip or spine. Adjusting for age, sex, and weight as covariates, we performed two-point and multipoint linkage analyses using the variance component linkage analysis method implemented in Sequential Oligogenic Linkage Analysis Routines. We found little evidence of linkage of these five markers to bone mineral density at the spine, hip, wrist and total body bone mineral content. The maximum logarithm of odds score at these five markers was 0.25, and the maximum logarithm of odds score at D11S987 was 0.15. Therefore, although we cannot exclude the linkage of D11S987 region to bone mineral density variation, there is no evidence for linkage of the marker D11S987 on human chromosome 11q12-13 to bone mineral density variation in our study population.