BACKGROUND: Total knee arthroplasty is one of the most effective and successful operations for the treatment of various end-stage or severe knee diseases.However,there is no consensus about routine patela resurfacing in total knee arthroplasty.OBJECTIVE:To investigate the efficacy of patelar arthroplasty in one-stage bilateral total knee arthroplasty for the treatment of knee osteoarthritis.METHODS:Patients undergoing bilateral total knee arthroplasty were selected from the Department of Orthopedic Surgery,Affiliated Hospital of Qingdao University in China between February 2013 and February 2014.They were randomly assigned to two groups.Patelar resurfacing group received patelar arthroplasty.Non-patelar resurfacing group did not receive patelar arthroplasty.RESULTS AND CONCLUSION:At 3,6 and 12 months folowing the surgery,no significant difference in Knee Society Score and range of motion of knee joint was detected between the two groups (P＞0.05).12 cases experienced anterior knee pain,including 4(13％) of the patelar resurfacing group and 8(27％) of the non-patelar resurfacing group.There were no complications such as prosthesis fracture,loosening,displacement,patelar fracture or patelar necrosis,and patelar prosthesis revision.Results verified that patelar arthroplasty and non-patelar arthroplasty have the same short-term effectiveness in one-stage bilateral total knee arthroplasty for osteoarthritis.

BACKGROUND:At present, dexamethasone has been widely used in the perioperative period of major surgery in the orthopedics for reducing postoperative pain and nausea and vomiting, but the study on the application of methylprednisolone to reducing postoperative nausea and vomiting and pain after unilateral total knee arthroplasty is rarely reported.OBJECTIVE:To evaluate the effects and safety assessment of the application of methylprednisolone on postoperative nausea and vomiting and pain after unilateral total knee arthroplasty. METHODS:A total of 86 patients undergoing unilateral total knee arthroplasty were randomly assigned to two groups. Patients in the methylprednisolone group were given methylprednisolone 40 mg in intravenous drip within 24 hours during and after replacement. Patients in the control group were given an equal volume of saline in intravenous drip at the same time. The incidence of postoperative nausea and vomiting was observed and recorded at 0-6 hours, 6-24 hours, 24-48 hours, and 48-72 hours after surgery, as wel as the total incidence was recorded in both groups. Pain visual analogue scale (VAS) score at 6, 24, 48 and 72 hours after replacement, and knee joint scoring system (KSS) score at 3 days after replacement were recorded. C-reactive protein and fasting blood glucose were determined. The occurrence of adverse reactions postoperatively was recorded in 6-month fol ow-up in both groups. RESULTS AND CONCLUSION:(1) The total incidence rate of postoperative nausea and vomiting during 0-72 hours after surgery, and incidence rates of nausea and vomiting at 6 and 24 hours were significantly lower in the methylprednisolone group than in the control group (P<0.05). (2) Pain VAS score was significantly lower in the methylprednisolone group than in the control group at 6 and 24 hours after surgery (P<0.05). (3) KSS scores were significantly higher in the methylprednisolone group than in the control group after surgery (P<0.05). (4) C-reactive protein and fasting blood glucose were not significantly different between two groups before and after surgery (P>0.05). (5) The surgical incision was found to heal in 3-month fol ow-up and no postoperative infection occurred in both groups. (6) Results show that methylprednisolone can obviously reduce postoperative nausea and vomiting and pain in unilateral total knee arthroplasty, and did not increase the incidence of postoperative infection.

BACKGROUND: At present, studies concerning human umbilical cord blood mesenchymal stem cells (UCB-MSCs) transplantation for repair of rat spinal cord injury, brain tumor, and myocardial infarction have been reported, and studies that human UCB-MSCs were induced differentiation into osteogenic cells under certain conditions have also been reported at home and abroad. But application of UCB-MSCs transplantation in the treatment of osteonecrosis of animals has not yet been reported. OBJECTIVE: To observe the repair results of recombinant lentivirus vector tracing enhanced green fluorescent protein (EGFP)-transfected UCB-MSCs transplantation in treatment of ischemic necrosis of the femoral head in rabbits. METHODS: Bone morphogenetic protein-2 gene plasmid, recombinant lentivirus vector carrying EGFP and UCB-MSCs were co-cultured. Rabbit models of femoral head defects were made and randomly divided into 3 groups. There was no treatment in the normal group, control group with bone defects and experimental bone defects filled with UCB-MSCs tracing transfected by recombinant lentivirus vector carrying EGFP. At 4 and 8 weeks after treatment, the imaging and histological of the femoral head were observed.RESULTS AND CONCLUSION: Imaging and histology results showed that there were osteogenic response and new bone formation in the experimental group at 4 weeks, and the bone defects were basically repaired at 8 weeks after treatment. In the control group, the bone defects filled with fibrous connective tissue fiber connective tissues at 4 weeks, and the osteosclerosis could be found surrounding femoral head, bone defects filled with fibrous connective tissue fibers and bone trabecula distributed disorderly. The recombinant lentivirus vector tracing EGFP-transfected into UCB-MSCs has strong effects bone conduction and can repair ischemic necrosis of the femoral head.

BACKGROUND: Hormone use has become the primary cause of steroid-induced avascular necrosis of femoral head (SANFH). OBJECTIVE: This study used a combination of injection of horse serum and a large dose of corticosteroid to develop a hormone-induced rabbit model of early avascular necrosis of femoral head (ANFH), and preliminary discussed the pathogenesis of ANFH. METHODS: New Zealand rabbits were randomly divided into three groups. Methylprednisolone with horse serum group: horse serum (10 mL/kg) was injected. Three weeks later, 6 mL/kg of horse serum was injected. Two weeks later, 45 mg/kg of methylprednisolone was daily injected for 5 consecutive days. Methylprednisolone group: 45 mg/kg of methylprednisolone was daily injected for 5 consecutive days. Control group: no treatment was given. Serum cholesterol and triacylglycerol levels were detected at 1, 3, 7 and 14 days before and after hormone injection. MRI and histopathological detection was done in femoral head at 2, 4 and 8 weeks after hormone injection. RESULTS AND CONCLUSION: The serum triglyceride and total cholesterol in methylprednisolone with horse serum group and methylprednisolone group were higher than control group at 1 and 3 days after hormone injection (P < 0.01). MRI results displayed abnormal signal in femoral head at 4 weeks in methylprednisolone with horse serum group, but in the methylprednisolone group at 8 weeks. Histological detection results exhibited that at 4 weeks, some trabeculae were broken into fragments, and the empty bone lacunae increased. At 8 weeks, the trabeculae showed thinning and broken. There were large amount of empty bone lacunae with bone cell atrophy and larger fat cells which were fused into bubbles. In methylprednisolone group, the level of necrosis was lighter than methylprednisolone with horse serum group during each period. Results suggest that hormone combined with horse serum can successfully prepare early-stage hormone-induced ANFH.

BACKGROUND:To date, rivaroxaban has been a clinical y common anticoagulant in China;however, effective prophylaxis for venous thrombosis is associated with a markedly higher incidence of perioperative hemorrhagic complications. Although it has been reported that aspirin effectively prevents deep vein thrombosis and pulmonary embolism, the use of aspirin as a routine drug for venous thrombosis after total knee arthroplasty is stil controversial.
OBJECTIVE:To compare the efficacy and safety of aspirin and rivaroxaban for prevention of deep vein thrombosis after total knee arthroplasty.
METHODS:Total y 324 patients with osteoarthritis who underwent primary unilateral total knee arthroplasty were randomly divided into three groups. Twelve hours after the surgery, three groups were given aspirin, rivaroxaban and low-molecular-weight heparin respectively. Al three groups were treated for 14 days, and al of the patients were fol owed for 4 weeks.
RESULTS AND CONCLUSION:Compared with the low-molecular-weight heparin group, the incidence of deep vein thrombosis was lower (P<0.05), but hidden blood loss and wound complications were more common (P<0.05) in the rivaroxaban group. There were no significant differences between the low-molecular-weight heparin group and aspirin group in the incidence of deep vein thrombosis, hidden blood loss, wound complications or incidences of lower limb swel ing and subcutaneous ecchymosis (P>0.05). The results confirmed that rivaroxaban has a positive anticoagulation effect but leads to increases in wound complications in patients;there are no differences in efficacy and safety between aspirin and low-molecular-weight heparin, so aspirin as part of a multimodal anticoagulation therapy after total knee arthroplasty has good clinical safety and efficacy.

BACKGROUND:The blood loss and the need of blood transfusion after bilateral total knee arthroplasty are very high. Therefore, the use of medicine such as tranexamic acid in total knee arthroplasty is overheated in recent years. Tranexamic acid has been proved to be able to decrease the blood loss after total knee arthroplasty, while the study of its use in bilateral total knee arthroplasty is seldom. OBJECTIVE:To observe the effect and safety of tranexamic acid on perioperative blood loss and the change of hemoglobin in patients undergoing bilateral total knee arthroplasty. METHODS: We selected 69 patients who received bilateral total knee arthroplasty and divided them into two different groups randomly. The patients in the experimental group were given 1 g of tranexamie acid dissolved in 100 mL of 5% glucose solution through intravenous infusion. Those in control group were only given 5% glucose solution 100 mL. Total blood loss, intraoperative blood loss, the hidden blood loss, amount of postoperative drainage, the ratio of blood transfusion, hemoglobin, D-dimer, prothrombin time and activated partial thromboplastin time were studied and compared between the two groups. We also observed the incidence of thrombotic events between the two groups. RESULTS AND CONCLUSION:The blood loss of the experimental group was significantly lower compared to the control group (t=2.194-2.908,P < 0.05). The blood transfusion rate of experimental group was significantly lower compared to the control group (χ2=5.219,P=0.022). The hemoglobin of the experimental group was significantly higher than that of the control group at 3 and 5 days after replacement (t=-3.481, 2.319,P < 0.05). No significant difference in prothrombin time and activated partial thromboplastin time was detectable between the two groups before and after replacement (P > 0.05). Thrombotic events were not visible in both groups. Venous ultrasonography in the lower extremity did not reveal deep venous thrombosis. Above results suggest that tranexamic acid can significantly reduce intraoperative blood loss in patients undergoing bilateral total knee arthroplasty, decreases the requirement of blood transfusion and the dynamic change of hemoglobin, and does not increase the risk of thrombosis.

BACKGROUND: Mesenchymal stem cells (MSCs) exist in umbilical cord blood (UCB), currently, there is not a method to in vitro separate, culture and amplificate human UCB-MSCs effectively. OBJECTIVE: To explore factors that influence yields of UCB-MSCs. METHODS: The relationship between the success rate of yielding UCB-MSCs and several factors, such as gestational ages (≥40 weeks, 37 weeks and ≤32 weeks), the number of mononuclear cells (MNCs) in UCB (≥2.5×109/L, <2.5×109/L), the inoculum density of MNCs (1×107, 1×109, 1×1011/L), the concentration of fetal bovine serum (FBS, 5%, 10%, 15%, 20%) in culture medium, and whether the culture flask being coated with FBS or not beforehand, as well as relationships among these factors were investigated. RESULTS AND CONCLUSION: The success rate of yielding UCB-MSCs was up to 58.3%. The success rate decreased as the gestational ages increasing (P < 0.01). The success rate could be enhanced to 76.9% when the MNCs count was more than 2.5×109/L, and there was significant difference when comparing to that of the group (36.4%) with MNCs count less than 2.5×109/L (x2=8.07, P=0.005). There was a negative correlation between the MNCs count and the gestational ages in the specimens with the same volume of UCB (r=-0.95, P < 0.01). In the group with the cell inoculum density of 1×1011/L, the growth and proliferation of primary and subculturing MSCs were better than that of the groups with the cell inoculum density lower than 1×1011/L. The adherence of MSCs in the group with the culture medium containing 5% FBS happened much later than other 3 groups, while the purity of MSCs in this group was much higher. When comparing the passage rate, there was no significant difference among the 4 groups with different concentration of FBS. In the group of culture flask being coated with FBS beforehand, the purity and proliferation ability of MSCs was higher than that in the groups with culture flask not being coated. It is suggested that culture of UCB-MSCs was influenced by several factors. The success rate could be increased by choosing the fetus with relative lower gestational ages, collecting enough volume of UCB, inoculating cells with a higher density, choosing the medium with lower concentration of FBS, and coating the culture flask with FBS beforehand.

BACKGROUND: Up to now, there are few reports addressing the biological properties and differentiation potential of umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs). OBJECTIVE: To observe the biological characteristics, osteogenic and adipogenic differentiation potential of UCB-MSCs. METHODS: MSCs were harvested and cultured from UCB at various gestational ages (GA). Harvested UCB-MSCs were cultured primarily and subcultured, and then induced to differentiate into osteoblasts and adipocytes. RESULTS AND CONCLUSION: Under the inverted phase contrast microscope, UCB-MSCs adhered to the wall, showing fibroblast like morphology and whirlpool like growth alignment. Observation of the ultramicrostructure under transmission electron microscope showed that UCB-MSCs had a big cellnucleus, fewer cellular organelles and big karyoplasmic ratio.Allofthe growth curves of primary and passaged UCB-MSCs presented S-shaped. The 3rd and 5th passages of MSCs showed the strongest proliferation activity. The count of colony forming unit fibroblasts varied with GA, significant difference was found among the three GA groups (P < 0.05), and the lower GA group had a higher count of colony forming unit fibroblasts than that in the older GA group. Flow cytometry showed that these cells expressed CD29, CD44 and CD90 positively, but they failed to express hematopoiesis related molecules such as CD34 and CD45. When the MSCs were induced to osteogenic and adipogenic differentiation for 3 weeks, strong expression of alkaline phosphatase was found and the formation of a mineral extracellular matrix was detected by alizarin red staining were detected; and neutral lipid vacuoles were detected by oil red O staining. UCB-MSCs have similarmorphologicaland biological characteristics and cell surface molecule markers with MSCs derived from bone marrow, both of which have great capability of proliferation and regeneration. UCB-MSCs can be induced to osteoblasts and adipocytes in a suitable condition in vitro.

Objective To compare the clinical outcomes of irradiated versus non-irradiated deepfrozen bone-patellar tendon-bone (B-PF-B) ullograft in anterior cruciate ligament (ACL) reconstruction. Methods A total of 66 patients undergoing arthroecopic ACL reconstruction were prospectively random-ized consecutively into two groups, ie, Group A ( irradiated deep-frozen allograft, n = 34) and Group B ( non-irradiated deep-frozen allograft, n = 32). All ACL reconstructions were done by the same senior surgeon with the same arthroscopic technique. Before and after surgery, the clinical results were compared in aspects of general conditions, range of motion ( ROM), Pivot shift test, Lachman and Anterior Drawer Test (ADT), Daniel's one-leg hop and Harner's vertical jump tests, overall international knee docu-mentation committee (IKDC) rating and KT-2000 arthrometer testing. Results Of all, 63 patients in-eluding 32 patients in Group A and 31 in Group B were available for a follow-up of average 38 months ( mean 38.3 months in Group A and mean 37.7 months in Group B) and three lost follow-up. There was one patient with late septic infection. While there was no statistical difference in aspects of general condi-tions including hospital stay, duration of fever and complications ( P > 0. 05 ), but there was a trend that the patients in Group A had a longer postoperative duration of fever ( mean 8.9 days ) than Group B (mean 7.8 days). Physical examinations showed no statistical difference upon ROM in both groups ( P > 0. 05), while there was statistical difference between Lachman test and ADT ( P < 0.05 ). The positive Pivot shift test was found in 12 patients in Group A and 3 in Group B, with statistical difference ( P < 0. 05 ). KT-2000 testing showed a side-to-side difference of less than 3 mm in 26 patients in Group B and only 8 in Group A, and a side-to-side difference of more than 5 mm in two patients in Group B and 12 in Group A, with statistical difference (P < 0.05 ). The anterior and rotational stability was decreased sig-nificantly in Group A. No statistical difference was found between two groups in overall IKDC rating, Daniel' s one-leg hop and Harner' s vertical jump tests ( P > 0.05 ). However, the function and IKDC score tended to decrease in Group A. Conclusion The short term clinical outcomes of the ACL reconstruction with irradiated B-PT-B allograft are adversely affected and unsatisfactory, indicating a cautious use.

BACKGROUND: How to effectively and rapidly induce the osteogenic differentiation of human umbilical cord mesenchymal stem cells is the focus of the current stem cell research. Increasing evidence has demonstrated some growth factors, such as bone morphogenetic protein-2, have important effects on the transdifferentiation of umbilical cord mesenchymal stem cels into osteoblasts in vitro. However, widespread use of growth factors is limited because of high cost. Insulin is widely used in the cell culture and induction, but there is no report about the effect of insulin on the osteogenic differentiation of human umbilical cord mesenchymal stem cells. OBJECTIVE:To observe the effect of insulin on osteogenic differentiation of human umbilical cord mesenchymal stem cels and to explore the feasibility of human umbilical cord mesenchymal stem cell transplantation in the treatment of diabetic delayed fracture healing. METHODS:The passage 3 human umbilical cord mesenchymal stem cells were inoculated in two flasks, denoted as experimental group and control group. The insulin (10-7mmol/L) was added to the experimental group but not to the control group. The proliferative capacity of human umbilical cord mesenchymal stem cels was evaluated by cell count kit-8 and alkaline phosphatase activity. The osteogenic differentiation capacity of human umbilical cord mesenchymal stem cells was evaluated by measuring the protein and mRNA expressions of type I colagen as well as osteocalcin mRNA level. RESULTS AND CONCLUSION: After 1-2 weeks of induction, compared with the control group, insulin could significantly increase the number of human umbilical cord mesenchymal stem cells in the experimental group, the activity of alkaline phosphatase and expressions of type I collagen osteocalcin mRNA (P< 0.05). These data indicate that insulin can promote the proliferation and osteogenic differentiation of human umbilical cord mesenchymal stem cells.