Objective To investigate the effects of patient bone mass differences on the stability of unicondylar knee arthroplasty(UKA)prostheses.Methods A UKA finite element model was established to quantify the effects of five different bone quality conditions on the proximal tibial von Mises stress,bone-prosthesis fixation interface contact stress,and bone-prosthesis fixation interface micromotion,using the medial knee force and joint motion predicted by the individualized UKA musculoskeletal multibody dynamics model as boundary conditions.Results The influences of bone strength on the proximal tibia von Mises stress and bone-prosthesis fixation interface contact stress were not obvious,and the difference in peak values of the proximal tibia von Mises stress between two groups of models with the largest difference in bone strength was not more than 5％,and the difference in peak values of the bone-prosthesis fixation interface contact stress was only 2.37 MPa.However,the influence of bone strength on the bone-prosthesis fixation interface micromotion was significant,and the weaker bones were more prone to cause the bone-prosthesis fixation interface micromotion.However,bone strength had a significant effect on the bone-prosthesis fixation interface micromotion,and weak bone was more likely to cause changes in the bone-prosthesis fixation interface micromotion.Compared to patients with the neutral bone quality,the prosthesis fixation interface micromotion increased by 84.67％at 20％gait cycles for patients with the weakest bone quality.Conclusions UKA patients with a weaker bone quality have a higher risk of prosthesis loosening.It is recommended that surgeons should carefully choose their surgical strategy in order to reduce the rate of postoperative revision in UKA.

Objective To investigate the effects of patient bone mass differences on the stability of unicondylar knee arthroplasty(UKA)prostheses.Methods A UKA finite element model was established to quantify the effects of five different bone quality conditions on the proximal tibial von Mises stress,bone-prosthesis fixation interface contact stress,and bone-prosthesis fixation interface micromotion,using the medial knee force and joint motion predicted by the individualized UKA musculoskeletal multibody dynamics model as boundary conditions.Results The influences of bone strength on the proximal tibia von Mises stress and bone-prosthesis fixation interface contact stress were not obvious,and the difference in peak values of the proximal tibia von Mises stress between two groups of models with the largest difference in bone strength was not more than 5％,and the difference in peak values of the bone-prosthesis fixation interface contact stress was only 2.37 MPa.However,the influence of bone strength on the bone-prosthesis fixation interface micromotion was significant,and the weaker bones were more prone to cause the bone-prosthesis fixation interface micromotion.However,bone strength had a significant effect on the bone-prosthesis fixation interface micromotion,and weak bone was more likely to cause changes in the bone-prosthesis fixation interface micromotion.Compared to patients with the neutral bone quality,the prosthesis fixation interface micromotion increased by 84.67％at 20％gait cycles for patients with the weakest bone quality.Conclusions UKA patients with a weaker bone quality have a higher risk of prosthesis loosening.It is recommended that surgeons should carefully choose their surgical strategy in order to reduce the rate of postoperative revision in UKA.

Rosuvastatin(RVS)is an excellent drug with anti-inflammatory and lipid-lowering properties in the aca-demic and medical fields.However,this drug faces a series of challenges when used to treat atherosclerosis caused by hyperhomocysteinemia(HHcy),including high oral dosage,poor targeting,and long-term toxic side effects.In this study,we applied nanotechnology to construct a biomimetic nano-delivery system,macrophage membrane(M?m)-coated RVS-loaded Prussian blue(PB)nanoparticles(MPR NPs),for improving the bioavailability and targeting capacity of RVS,specifically to the plaque lesions associated with HHcy-induced atherosclerosis.In vitro assays demonstrated that MPR NPs effectively inhibited the Toll-like receptor 4(TLR4)/hypoxia-inducible factor-1α(HIF-1α)/nucleotide-binding and oligomerization domain(NOD)-like receptor thermal protein domain associated protein 3(NLRP3)signaling pathways,reducing pyroptosis and inflammatory response in macrophages.Additionally,MPR NPs reversed the abnormal distribution of adenosine triphosphate(ATP)-binding cassette transporter A1(ABCA1)/ATP binding cassette transporter G1(ABCA1)/ATP binding cassette transporter G1(ABCG1)caused by HIF-1α,promoting cholesterol efflux and reducing lipid deposition.In vivo studies using apolipoprotein E knockout(ApoE-/-)mice confirmed the strong efficacy of MPR NPs in treating atherosclerosis with favorable bio-security,and the mechanism behind this efficacy is believed to involve the regulation of serum metabolism and the remodeling of gut microbes.These findings suggest that the synthesis of MPR NPs provides a promising nanosystem for the targeted therapy of HHcy-induced atherosclerosis.

Objective To investigate the biomechanical effects of the backside design of tibial trays on the bone-prosthesis fixation interfaces in unicompartmental knee arthroplasty(UKA).Methods Finite element models of medial knee arthroplasty were constructed using a fixed UKA prosthesis.The knee joint load and joint motion under walking motion were considered as boundary conditions,and the differences in tibial von Mises stress,contact stress,and micromotion of the bone-prosthesis fixation interface of the UKA tibial trays with big keel,small keel,two-peg with fin,three-oblique peg,and three-upright peg types were compared.Results At the maximum medical knee force moment,compared to the two-peg with fin type,the tibial von Mises stress,contact stress,and micromotion of the bone-prosthesis fixation interface decreased by 8%and 15.9%and increased by 9.9%for the big keel type;decreased by 12.3%and increased by 7.5%and 0.9%for the small keel type;decreased by 10%,10.5%,and increased by 1.2%for the three-oblique peg type;and decreased by 7.7%,14.7%,and 1.6%for the three-upright peg type,respectively.However,the maximum micromotion of the bone-prosthesis fixation interface occurred at 21%of the gait cycle.Compared to the two-peg with fin type,the micromotion of the bone-prosthesis fixation interface increased by 11.6%for the big keel type,increased by 1.6%for the small keel type,decreased by 0.4%for the three-oblique peg type,and decreased by 2.3%for the three-upright peg type.Conclusions To improve the long-term fixation effects of tibial prostheses,it is recommended to focus on a two-upright peg with fin or small keel designs when UKA tibial trays are designed,which can effectively balance the stress transfer and interface micromotion,thereby ensuring prosthesis stability and reducing the risk of aseptic loosening.

Objective Aiming at the medial prosthetic loosening failure and lateral cartilage degeneration after unicompartmental knee arthroplasty ( UKA), the effects of prosthetic installation errors of joint line in UKA on knee contact mechanics and kinematics during different physiologic activities were studied using musculoskeletal multi-body dynamic method. Methods Taking the medial natural joint line as 0 mm error, six installation errors ofjoint line including ±2 mm, ±4 mm and ±6 mm were considered respectively, and seven musculoskeletal multi body dynamic models of medial UKA were established, to comparatively study the variations in knee contact mechanics and kinematics during walking and squatting. Results At 70% of walking gait cycle, compared with 0 mm error, the medial prosthetic contact force was increased by 127. 3% and the contact force of the lateral cartilage was decreased by 12. 0% under 2 mm elevation in joint line, the medial prosthetic contact force was close to 0 N, but the lateral cartilage contact forces were increased by 10. 1% under 4 mm reduction in joint line. The tibiofemoral total contact forces were increased by 19. 7% and decreased by 14. 2% under 2 mm elevation and 2 mm reduction in joint line, respectively. At the 100°knee flexion during squatting, compared with 0 mm error, the medial prosthetic contact force and the tibiofemoral total contact force increased by 31. 6% and 11. 1% under 2 mm elevation in joint line, and decreased by 24. 5% and 8. 5% under 2 mm reduction in joint line, respectively. The change in the lateral cartilage contact force was not marked. Moreover, at 70% of walking gait cycle, the varus angle decreased, the internal rotation and the anterior translation increased along with the elevation of joint line in UKA, while it was just the opposite along with the reduction of joint line in UKA. The trends of the varus valgus movement and anterior-posterior translation during squatting were consistent with those during swing phase of walking, but the trend of the internal-external rotation was opposite. Conclusions In order to reduce the risk of medial prosthetic loosening failure and lateral cartilage degeneration, it is recommended that the installation error of joint line in UKA should be controlled in the range of -2 mm to +2 mm. This study provides theoretical basis for UKA clinical failure caused by changes in joint line

Objective To investigate the value of postprocessing technique of multi-slice helical CT for the occult fracture located in complicated structure. Methods One hundred-thirteen patients with acute trauma but negative on plain X-ray film were reviewed retrospectively. All of the patients underwent MSCT ,and original data were reformed with reconstruction. Results Of one hundred-thirteen injuried patients , fractures were demonstrated with MSCT imaging in forty-eight cases. Conclusion The combination use of axial image of MSCT , reconstruction and post-processing is of high value in definite detection of occult fracture , and play an important role in selecting therapy project and evaluating prognosis.

Objective: To evaluate the impact of anemia on prognosis of elder patients with acute coronary syndrome (ACS) after percutaneous coronary intervention (PCI).
Methods: A total of 908 consecutive ACS patients elder than 60 years of age with PCI in our hospital from 2010-06 to 2012-06 were studied. According to WHO deifnition of anemia (HB<12.0 g/dL in female and HB<13.0 g/dL in male), the patients were classiifed as Anemia group, n=283 and Non-anemia group, n=625. The patients were followed-up for 1 year. The basic clinical characteristics, incidences of mortality and major adverse cardiovascular and cerebravascular events (MACCE) were compared between 2 groups by cardiac death, myocardial re-infarction, worsening of cardiac function, target vessel revascularization, cerebral hemorrhage and cerebral infarction.
Results: There were 31%of patients suffering from anemia. Anemia group had more patients with the elder age, female gender, diabetes, hypertension, chronic kidney disease, decreased LVEF, more patients with 3 vessel-disease, and higher mortality at 1 year after PCI, higher rate of MACCE than those in Non-anemia group, all P<0.05. Multiple regression analysis indicated that anemia is the independent predictor for mortality in elder ACS patients at 1 year after PCI, P<0.05.
Conclusion: Anemia may increase the incidences of mortality and MACCE in elder ACS patients after PCI for a long-term.