Pei Fuxing

Lovastatin inhibits adipogenesis and prevents osteonecrosis in steroid-treated rabbits

OBJECTIVES To investigate in vivo effects of lovastatin on inhibition of adipogenesis, an important mechanism of steroid-induced osteonecrosis, and on prevention of occurrence of steroid-induced osteonecrosis in rabbits. METHODS Fifty-four rabbits were intramuscularly injected once with 20mg/kg of methylprednisolone acetate (MPSL). Then, they were divided into two groups: lovastatin was given in Group I and placebo was given in Group II. And another 16 rabbits were injected with physiologic saline (PS) as a control (Group III). Hematological examination was performed for serum lipid levels. Both the femora and the humeri were histopathologically examined for the presence of osteonecrosis before the injection and 1, 2, 4 and 12 weeks after the injection. RESULTS The serum lipid levels were significantly higher in Group II than in Groups I and III 1, 2 and 4 weeks after the injection. The incidence of osteonecrosis was significantly higher in Group II (69%) than in Group I (36%) and Group III (0%). Pathological examination showed less serious adipogenesis and bone death in Group I than in Group II. The size and area of the fat cells in the bone marrow were significantly smaller in Group I (47.5+/-1.3 microm, 25%) and Group III (41.7+/-1.6 microm, 12%) than in Group II (59.8+/-6.3 microm, 51%) (P< 0.001). CONCLUSION Lovastatin can prevent development of steroid-induced osteonecrosis in rabbits by inhibiting adipogenesis. Future evaluation on the effectiveness of lovastatin in the clinical practice is still necessary.

Tranexamic Acid Administration in Primary Total Hip Arthroplasty: A Randomized Controlled Trial of Intravenous Combined with Topical Versus Single-dose Intravenous Administration

BACKGROUND The use of tranexamic acid (TXA) in primary total hip arthroplasty is well documented. However, considering the potential side effects, including deep vein thrombosis and pulmonary embolism, the ideal method of providing TXA to patients undergoing total hip arthroplasty remains controversial. The objective of this trial was to assess the efficacy and safety of intravenous (IV) administration combined with topical administration of TXA regarding postoperative blood loss and transfusion rates in patients treated with primary unilateral total hip arthroplasty. METHODS In this prospective, randomized controlled trial, 150 patients were divided into three groups: the combined group (IV administration of 15 mg/kg of TXA combined with topical administration of 1 g/100 mL of TXA), the single IV group (IV administration of 15 mg/kg of TXA), and the placebo group. The primary outcomes included blood-loss variables (total, intraoperative, and drainage blood loss; changes in hemoglobin, hematocrit, and platelet concentration; and amount of IV transfusion fluid) and transfusion values (frequency of transfusion and number of transfused blood units). The secondary outcomes included the length of the hospital stay, range of hip motion, Harris hip score, and prevalences of deep vein thrombosis and pulmonary embolism. RESULTS The total blood loss in the combined group (mean and standard deviation, 835.49 ± 343.50 mL) was significantly reduced (p < 0.05) in comparison with that in the single IV group (1002.62 ± 366.85 mL) and placebo group (1221.11 ± 386.25 mL). The combined group also had fewer transfusions in comparison with the single IV and placebo groups (1, 8, and 19, respectively; p < 0.05). There was no difference among the 3 groups with regard to the rates of deep vein thrombosis or pulmonary embolism. CONCLUSIONS Intravenous combined with topical administration of TXA in patients undergoing a primary unilateral total hip arthroplasty significantly reduced postoperative bleeding and the transfusion rate. Studies with more patients and longer follow-up are needed to confirm whether this promising combined strategy is safe with regard to thromboembolic complications. LEVEL OF EVIDENCE Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Appling the abdominal aortic-balloon occluding combine with blood pressure sensor of dorsal artery of foot to control bleeding during the pelvic and sacrum tumors surgery.

To investigate the feasibilities of reducing intraoperative hemorrhage and improving the safety of pelvic and sacrum tumor surgery using sizing balloon occluding abdominal aorta.

Clinical Results and Metal Ion Levels After Ceramic-on-Metal Total Hip Arthroplasty: A Mean 50-Month Prospective Single-Center Study

BACKGROUND The aim of our study was to investigate the clinical results and serum metal ion levels in a cohort of patients who received total hip arthroplasty (THA) with ceramic-on-metal (CoM) bearings. METHODS From September 2009 to December 2011, 78 patients (89 hips) who underwent THA with CoM bearings were involved in this study. Harris Hip Score, Short-Form 12, and Western Ontario and McMaster Universities Osteoarthritis Index scores were measured and radiographs were taken for radiographic analysis. Serum metal ion levels of cobalt (Co), chromium (Cr), molybdenum (Mo), and titanium (Ti) were measured using high-resolution inductively coupled plasma-mass spectrometry. RESULTS Severy-four patients (85 hips) were followed up at a mean of 50 months. At the end of follow-up, HSS, Short-Form 12, and Western Ontario and McMaster Universities Osteoarthritis Index scores were improved significantly compared with preoperative values. No intraoperative and postoperative complications occurred, and no radiolucency, osteolysis, and loosening was found from radiographic examination. Metal ion analysis showed that serum metal ions levels were significantly elevated compared with normal values. Spearman correlation analysis revealed that there was a correlation between 3 metal ion levels and body mass index(Co: r = 0.49, P < .01; Cr: r = 0.47, P < .01; Mo: r = 0.36, P = .04). No correlation was found between metal ion levels and age, cup abduction angle, cup anteversion angle, acetabular version, bilateral arthroplasty, cup screw used, hip stem implant type, or femoral head size. CONCLUSION Our study concluded that the use of a CoM THA is effective clinically, but the systemic metal ion levels are significantly elevated at midterm follow-up. Whether the elevated metal ion levels will induce an adverse reaction is unknown and long-term follow-up is need.

Characteristics of crush syndrome caused by prolonged limb compression longer than 24 h in the Sichuan earthquake

Background To assess the characteristics, treatment and outcome of patients with crush syndrome caused by prolonged limb compression longer than 24 h in the Sichuan earthquake. Methods Following the Sichuan earthquake, 2728 patients were transferred to the West China Hospital of Sichuan University and 157 of those were admitted to the intensive care unit. The medical records of nine severe crush syndrome patients were retrospectively reviewed. Results The major associated injuries were in the lower extremities. Renal failure and oliguria developed in all patients. Creatine kinase peaked in all patients. Hyperkalaemia was seen in five patients, and six patients developed acidosis. All patients had amputations; five had two limbs amputated. One patient underwent fasciotomy. Adult respiratory distress syndrome developed in four patients and required mechanical ventilation. All patients underwent haemodialysis. Multiple organ failure and sepsis developed in eight patients, but no patients died. Conclusions Crush syndrome caused by extremely long compression has high rates of renal failure, multiple organ failure, sepsis and amputation. Early transportation and immediate intensive care therapy would have improved the outcome and survival rate.

Evaluation of bioabsorbable multiamino acid copolymer/α-tri-calcium phosphate interbody fusion cages in a goat model.

Study Design. A study of cervical interbody fusion using polyamino acid-based bioabsorbable fusion cages in a goat model. Objective. To compare interbody fusion of a bioabsorbable multiamino acid copolymer/&agr;-tri-calcium phosphate (MAACP/&agr;-TCP) fusion cage with an autologous tricortical iliac-crest bone graft and a titanium cage. Summary of Background Data. Polyamino acid is widely used as a carrier for drug delivery. To our knowledge, no study investigates interbody fusion cage made of polyamino acid. Methods. A total of 15 sheep underwent C3/C4 discectomy and fusion. The following stabilization techniques were used: group A, autologous tricortical iliac crest bone graft (n = 5); group B, MAACP/&agr;-TCP cage filled with autologous cancellous bone graft (n = 5); group C, titanium cage filled with autologous cancellous bone graft (n = 5). Radiographic scans to determine disc space height were performed before and after surgery and after 4, 8, and 12 weeks, respectively. After 12 weeks, the C3/C4 motion segment was isolated and sectioned to create a 5-mm thick parasagittal section from which lateral radiographs were obtained. All the radiographs were encoded and reviewed in a blinded fashion to evaluate interbody fusion within the cage devices according to a three-point radiographic score. Biomechanical testing was performed in flexion, extension, axial rotation, and lateral bending to determine range of motion (ROM). Histomorphological and histomorphometrical analyses were performed to evaluate fusion and foreign-body reactions associated with the bioabsorbable cages. Results. Radiographic results showed that the disc space height (DSH) in MAACP/&agr;-TCP cage group was better than that of bone graft group and the best radiographic score was found in MAACP/&agr;-TCP cage group. Biomechanical test showed that no significant difference was found in ROM between MAACP/&agr;-TCP cage group and titanium cage group whereas the value of ROM in bone graft group was the largest. Histologic evaluation showed a higher intervertebral bone volume/total volume ratio and a better interbody fusion in the MAACP/&agr;-TCP cage group than in the other two groups. Two MAACP/&agr;-TCP cages showed microcracks and the other three cages had maintained their original geometry. All MAACP/&agr;-TCP cages showed excellent biocompatibility. Conclusion. After 12 weeks, there was no significant difference between the MAACP/&agr;-TCP cage and the titanium cage in distractive properties and biomechanical properties. Compared with titanium cages, MAACP/&agr;-TCP cages showed an advanced interbody fusion. Although MAACP/&agr;-TCP cages developed cracks after only 12 weeks, they showed significantly better distractive properties, biomechanical properties, and an advanced interbody fusion than the tricortical iliac crest bone graft. Improvement should be made to insure the strength of MAACP/&agr;-TCP cage last at least 6 month after implantion.

Primary Total Hip Arthroplasty With Duraloc Cup in Patients Younger Than 50 Years: A 5- to 7-Year Follow-Up Study

We evaluated the clinical and radiographic results of 67 (64 patients) cementless Duraloc-300 cups for young active patients after a mean follow-up period of 6.2 years. The preoperative mean Harris hip score improved from 46.24 to 96.5 points at 5 years. The survivorship of the cup, using radiographically confirmed aseptic loosening as the end point, was 100% at 5 years. The mean rate of liner wear was 0.125 mm/y (00-0.39 mm/y). Acetabular osteolysis was found in 14% (9 hips) of the 67 hips, and the osteolysis is related to polyethylene wear (P = .0024) and sex (P = .001). Although there was no aseptic loosening of the components, there was a high rate of liner wear of the polyethylene liner and acetabular osteolysis.

No Decreased Infection Rate When Using Antibiotic-Impregnated Cement in Primary Total Joint Arthroplasty

There has been much debate and controversy about the routine use of antibiotic-impregnated bone cement in primary total joint arthroplasty. The purpose of this study was to undertake a meta-analysis to determine whether the use of antibiotic-impregnated bone cement would reduce the incidence of infection after primary total joint arthroplasty. Of 313 citations identified for screening, 6 trials reporting 26,791 patients were eligible for data extraction and meta-analysis. The authors found no statistically significant difference between antibiotic-impregnated bone cement and plain bone cement in terms of the incidence of infection. The results indicated that the use of antibiotic-impregnated bone cement in primary total joint arthroplasty did not lead to a decrease in the rate of infection.

Infectious complications in patients with crush syndrome following the Wenchuan earthquake

Objective: To analyze the results of clinical and bacteriological examinations in patients with crush syndrome who suffered infectious complications after an earthquake in Sichuan, China. Methods: A total of 313 bacteriological samples among 147 patients with crush syndrome were collected. Infectious complications, results of microbiological examinations, potential risk factors of infection and mortality were analyzed statistically. Results: In the obtained database, 112 out of the 147 (75.7%) patients had infectious complications, in which, wound infection, pulmonary infection, and sepsis were most common. The time under the rubble and the time from injury to treatment were related to the occurrence of wound infection (P=0.013, odds ratio 2.25; P=0.017, odds ratio 2.31). Sepsis and wound infection were more common in patients who underwent fasciotomy or amputation than in those who did not (P=0.001). Conclusion: Quick rescue and injury treatment can decrease the infection risk in crush syndrome patients. It is better to obtain microorganic proofs before applying antibiotics, and bacteriological and drug sensitivity data should be taken into account, especially considering that most of these infections are hospital‐acquired and drug resistance. Emphasizing the accuracy and efficiency of wound management in emergency situations, cautiously assessing the indications for fasciotomy to avoid open wounds from unnecessary osteofascial compartment decompression incisions may decrease the incidence of infection and ameliorate the prognosis.