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Purpose: Wear debris particle-induced periprosthetic osteolysis is a severe complication of total joint replacement that results in aseptic loosening and subsequent arthroplasty failure. No effective therapeutic agents or drugs have been approved to prevent or treat osteolysis; thus, revision surgery is often needed. Extracellular vesicles (EVs) are vital nanosized regulators of intercellular communication that can be directly applied to promote tissue repair and regeneration. In this study, we assessed the therapeutic potential of EVs from human urine-derived stem cells (USCs) (USC-EVs) in preventing ultrahigh-molecular-weight polyethylene (UHMWPE) particle-induced osteolysis., Methods: USCs were characterized by measuring induced multipotent differentiation and flow cytometry. USC-EVs were isolated and characterized using transmission electron microscopy (TEM), dynamic light scattering (DLS) and Western blotting. RAW264.7 cells and bone marrow mesenchymal stem cells (BMSCs) were cultured with USC-EVs to verify osteoclast differentiation and osteoblast formation, respectively, in vitro. The effects of USC-EVs were investigated on a UHMWPE particle-induced murine calvarial osteolysis model by assessing bone mass, the inflammatory reaction, and osteoblast and osteoclast formation., Results: USCs differentiated into osteogenic, adipogenic and chondrogenic cells in vitro and were positive for CD44, CD73, CD29 and CD90 but negative for CD34 and CD45. USC-EVs exhibited a cup-like morphology with a double-layered membrane structure and were positive for CD63 and TSG101 and negative for calnexin. In vitro, USC-EVs promoted the osteogenic differentiation of BMSCs and reduced proinflammatory factor production and osteoclastic activity in RAW264.7 cells. In vivo, local injection of USC-EVs around the central sites of the calvaria decreased inflammatory cytokine generation and osteolysis compared with the control groups and significantly increased bone formation., Conclusion: Based on our findings, USC-EVs prevent UHMWPE particle-induced osteolysis by decreasing inflammation, suppressing bone resorption and promoting bone formation., Competing Interests: The authors have no conflicts of interest to declare., (© 2021 Li et al.)

Osteosarcoma has been the most common malignant bone tumor in children and adolescents, while the 5-y survival of osteosarcoma patients gained no significant improvement over the past decades. This study aimed to explore the role of ferroptosis-related genes (FRGs) in the development and prognosis of osteosarcoma. The datasets of osteosarcoma patients including RNA sequencing data and clinical information were acquired from the TRGET and Gene Expression Omnibus (GEO) databases. The identification of molecular subgroups with different FRG expression patterns was achieved through nonnegative matrix factorization (NMF) clustering. The prognostic model was constructed using the least absolute shrinkage and selection operator (LASSO) algorithm and multivariate Cox regression analysis. The ESTIMATE algorithm was applied for determining the stromal score, immune score, ESTIMA score, and tumor purity of osteosarcoma patients. Functional analyses including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, Gene Set Enrichment Analysis (GSEA), and Gene Set Variation Analysis (GSVA) were conducted to explore the underlying mechanisms in the development and prognosis of osteosarcoma. Two molecular subgroups with different FRGs expression patterns were identified. The molecular subgroups with higher immune score and more active immune status showed better prognostic survival. On the basis of FRGs, a prognostic model and a nomogram integrating clinical characteristics were constructed and their prediction efficiency for osteosarcoma prognosis were well validated. Gene functional enrichment analysis showed that these differentially expressed FRGs were mainly enriched in immunity-related signaling pathways, indicating that FRGs may affect the development and prognosis of osteosarcoma by regulating the immune microenvironment. The expression profiles of FRGs were closely related to the immunity status and prognostic survival of osteosarcoma patients. The interaction between ferroptosis and immunity in the development of osteosarcoma could provide a new insight into the exploration of molecular mechanisms and targeted therapies of osteosarcoma patients., (© 2021 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Objective: To investigate the accuracy of split three-dimensional (3D) printing patient-specific instrumentation (PSI) in medial open-wedge high tibial osteotomy (MOWHTO) and its effectiveness in treating medial knee osteoarthritis., Methods: Clinical data of 14 patients with medial knee osteoarthritis and treated with split 3D printing PSI-assisted MOWHTO between August 2019 and August 2020 were retrospectively analyzed. There were 5 males and 9 females with an average age of 61 years (range, 43-68 years). The disease duration ranged from 1 to 16 years, with an average of 4.7 years. Preoperative Kellgren-Lawrence grading of knee osteoarthritis included grade Ⅰ in 2 cases, grade Ⅱ in 6 cases, and grade Ⅲ in 6 cases. The Hospital for Special Surgery (HSS) score was 59.1±4.9. The weight bearing line ratio (WBL), hip-knee-ankle angle (HKA), medial proximal tibial angle (MPTA), posterior tibial slope angle (PTSA), and actual correction angle of the lower limbs were measured on postoperative imaging data, and compared with the preoperative measurements and the designed target values to evaluate the accuracy of the PSI-assisted surgery. The patients' knee function were evaluated with the HSS score at 3 and 6 months postoperatively, and at last follow-up., Results: One patient suffered from an incision exudation at 2 weeks postoperatively, and the incision healed after symptomatic treatment. The incisions of other patients healed by first intention. All patients were followed up 7-19 months (mean, 14.8 months). There was no neural injuries, hinge fracture, plate or screw fractures, loosening, or other complications. The WBL was maintained at the postoperative level according to the X-ray examination during the follow-up period. The WBL, HKA, MPTA, and PTSA were all within a satisfactory range after operation. The WBL, HKA, and MPTA were significantly improved when compared with the preoperative measurements ( P <0.05). There was no significant difference between preoperative and postoperative PTSA ( P >0.05). The differences in postoperative WBL, HKA, MPTA, and correction angle compared with the preoperative designed target values were not significant ( P >0.05). The HSS scores were 69.2±4.7, 77.7±4.3, and 88.1±5.4 at 3 and 6 months postoperatively, and last follow-up, respectively. The differences between time points were significant ( P <0.05)., Conclusion: For patients with medial knee osteoarthritis, the split 3D printing PSI can assist the surgeon in MOWHTO with accurate osteotomy orthopedics and achieve favorable effectiveness.

Polyvinyl alcohol (PVA) hydrogel has gained interest in cartilage repair because of its highly swollen, porosity, and viscoelastic properties. However, PVA has some deficiencies, such as its poor biocompatibility and microstructure. This research aimed to design novel hydroxyapatite (HA)-collagen (COL)-PVA hydrogels. COL was added to improve cell biocompatibility, and the microstructure of the hydrogels was controlled by fused deposition modeling (FDM). The feasibility of the COL-HA-PVA hydrogels in cartilage repair was evaluated by in vitro and in vivo experiments. The scanning electron microscopy results showed that the hybrid hydrogels had interconnected macropore structures that contained a COL reticular scaffold. The diameter of the macropore was 1.08-1.85 mm, which corresponds to the diameter of the denatured PVA column. The chondrocytes were then seeded in hydrogels to assess the cell viability and formation of the cartilage matrix. The in vitro results revealed excellent cellular biocompatibility. Osteochondral defects (8 mm in diameter and 8 mm in depth) were created in the femoral trochlear of goats, and the defects were implanted with cell-seeded hydrogels, cell-free hydrogels, or a blank control. The in vivo results showed that the COL-HA-PVA hydrogels effectively repaired cartilage defects, especially the conditions inoculated with chondrocyte in advance. This research suggests that the COL-HA-PVA hydrogels have promising application in cartilage repair., (© 2021. The Author(s).)

Despite the widespread application of Ti6Al4V and tantalum (Ta) in orthopedics, bioinertia and high cost limit their further applicability, respectively, and tremendous efforts have been made on the Ti6Al4V-Ta alloy and Ta coating to address these drawbacks. However, the scaffolds obtained are unsatisfactory. In this study, novel high-interface-strength Ti6Al4V-based porous Ta scaffolds were successfully manufactured using Laser Powder Bed Fusion for the first time, in which porous Ta was directly manufactured on a solid Ti6Al4V substrate. Mechanical testing revealed that the novel scaffolds were biomechanically compatible, and the interfacial bonding strength was as high as 447.5 MPa. In vitro biocompatibility assay, using rat bone marrow mesenchymal stem cells (r-BMSCs), indicated that the novel scaffolds were biocompatible. Alkaline phosphatase and mineralized nodule determination demonstrated that the scaffolds favored the osteogenic differentiation of r-BMSCs. Moreover, scaffolds were implanted into rabbits with femur bone defects, and imaging and histological evaluation identified considerable new bone formation and bone ingrowth, suggesting that the scaffolds were well integrated with the host bone. Overall, these results demonstrated good mechanical compatibility, biocompatibility, and osteointegration performance of the novel Ti6Al4V-based porous Ta scaffold, which possesses great potential for orthopedic clinical applications., Competing Interests: The authors declare that they have no conflicts of interest., (© 2021 The Authors.)

Objective: To simulate and validate the performance, accuracy, and safety of the Yuanhua robotic-assisted total knee arthroplasty system (YUANHUA-TKA) through cadaver-based experiment, thus optimizing the robotic system for the future human clinical application., Methods: Six unilateral adult cadaver specimens of the lower limbs were scanned by three-dimensional CT before the experiment, and then the three-dimensional models of femur and tibia were obtained by using the preoperative software of YUANHUA-TKA system, so as to plan the type of prosthesis implant, the osteotomy volume and osteotomy angles [hip-knee-ankle angle (HKA), coronal frontal femoral component (FFC) and frontal tibial component (FTC)], the ideal value of HKA was set to 180°, and of FFC and FTC were set to 90°, respectively. The operator could further confirm the osteotomy plan according to the intraoperative situation before osteotomy, and then install the prosthesis after completing the osteotomy in each plane with the assistance of YUANHUA-TKA system. At last, the X-ray films of hip joint, knee joint, and ankle joint were taken and stitched into the full length X-ray film of the lower limb, and HKA, coronal FFC and FTC were measured., Results: During the experiment, YUANHUA-TKA system ran stably. All sections of femur and tibia were smooth and no ligament injury was found. After operation, the HKA was 177.1°-179.7°, FFC was 87.9°-91.4°, and FTC was 87.3°-91.4°, which were within ±3° from the ideal values of preoperative planning., Conclusion: The YUANHUA-TKA system can assist the surgeon to carry out precise osteotomy according to the preoperative planned value, which has a good auxiliary effect for total knee arthroplasty. It is expected to assist joint surgeons to improve the surgical accuracy in clinical application.

An intermittent closure with silk suture is routinely used for closing different surgical wounds. However, subcuticular closure with absorbable sutures has gained considerable attention due to convenience and better cosmetic appearance.To compare the clinical outcomes and risk of surgical-site infection of subcuticular and intermittent closure after total-knee arthroplasty (TKA), 106 patients that underwent TKA between January 2017 to June 2019 at the Department of Orthopedics in Xiangya Hospital of Centre South University were retrospectively assessed. Forty-three had received running subcuticular closure (group A) and 58 underwent intermittent closure (group B). The Knee Society score was measured before and 6 months after operation. Inflammation markers including the serum levels of procalcitonin, interleukin-6, and C-reactive protein, and the erythrocyte sedimentation rate were evaluated before operation, 1 day after and 1 month after operation. Patient satisfaction with the closure was evaluated using the Likert scale at the last follow-up.No significant difference was seen in the 6-month postoperative Knee Society score, or in the 1-day and 6-month postoperative inflammation marker levels between both groups (P > .05). Likert scores were higher in group A compared to group B (4.0 ± 1.0 vs 3.6 ± 1.2, P < .05).Running subcuticular closure after TKA results in a better appearance compared to intermittent closure, although neither method has an advantage in terms of efficacy and risk of infection.

Background: A simulation and model (SM) teaching aid using 3D printing was developed to improve a training course for total hip arthroplasty of adult developmental dysplasia of the hip (adult DDH-THA). We named this new method Surgery Simulation Teaching based on a Real Reconstruction Aid (RRA-SST). A prospective randomized comparison was performed with the traditional surgical live teaching method to evaluate the training effectiveness of RRA-SST for adult DDH-THA., Methods: Twenty-six trainees, who were already practicing but were not experienced, participated in the study. We randomly divided the trainees into two groups: Group A (n = 13) received RRA-SST and group B (n = 13) received traditional surgical live teaching. A surgery simulation test and a questionnaire were used for evaluation. Next, each group received training with the other teaching method, and then the test and questionnaire were used again for evaluation., Results: After the first test, the RRA-SST method was shown to produce better results than the traditional surgical live teaching method. After the second test, the results showed the training effect in both groups reached the same level, which was level as Group A RRA-SST results. Analysis of the questionnaire results showed that the training effect of RRA-SST was higher than that of traditional surgical live teaching, from multiple perspectives., Conclusions: The use of RRA-SST improved participant performance according to simulation assessment. RRA-SST can be helpful for trainees who are already practicing but not experienced when developing proficiency in adult DDH-THA surgical techniques.

Pain is the most prominent symptom of osteoarthritis (OA) progression. However, the relationship between pain and OA progression remains largely unknown. Here we report osteoblast secret prostaglandin E2 (PGE2) during aberrant subchondral bone remodeling induces pain and OA progression in mice. Specific deletion of the major PGE2 producing enzyme cyclooxygenase 2 (COX2) in osteoblasts or PGE2 receptor EP4 in peripheral nerve markedly ameliorates OA symptoms. Mechanistically, PGE2 sensitizes dorsal root ganglia (DRG) neurons by modifying the voltage-gated sodium channel Na V 1.8, evidenced by that genetically or pharmacologically inhibiting Na V 1.8 in DRG neurons can substantially attenuate OA. Moreover, drugs targeting aberrant subchondral bone remodeling also attenuates OA through rebalancing PGE2 production and Na V 1.8 modification. Thus, aberrant subchondral remodeling induced Na V 1.8 neuronal modification is an important player in OA and is a potential therapeutic target in multiple skeletal degenerative diseases., Competing Interests: JZ, GZ, SA, XW, MW, YL, ZC, YG, XD, YH, XC No competing interests declared, (© 2020, Zhu et al.)

Background: Poly(vinyl alcohol) (PVA) hydrogels have been widely used in synthetic cartilage materials. However, limitations of PVA hydrogels such as poor biomechanics and limited cell ingrowth remain challenges in this field., Methods: This work aimed to design novel nano-hydroxyapatite (nano-HA)/poly(vinyl alcohol) (PVA) hydrogels coated with a poly(lactic-co-glycolic acid) (PLGA)/nano-HA/PVA scaffold to counter the limitations of PVA hydrogels. The core, comprising nano-HA/PVA hydrogel, had the primary role of bearing the mechanical load. The peripheral structure, composed of PLGA/nano-HA/PVA, was designed to favor interaction with surrounding cartilage., Results: The double-layer HA/PVA hydrogel coated with PLGA/HA/PVA scaffold was successfully prepared using a two-step molding method, and the mechanical properties and biocompatibility were characterized. The mechanical properties of the novel PLGA/HA/PVA scaffold modified HA/PVA hydrogel were similar to those of native cartilage and showed greater sensitivity to compressive stress than to tensile stress. Rabbit chondrocytes were seeded in the composites to assess the biocompatibility and practicability in vitro. The results showed that the peripheral component comprising 30 wt% PLGA/5 wt% HA/15 wt% PVA was most conducive to rabbit chondrocyte adhesion and proliferation., Conclusions: The study indicated that the double-layer HA/PVA hydrogel coated with PLGA/HA/PVA scaffold has the potential for cartilage repair.

Objective: To compare the effectiveness of the intermittent suture and the cosmetic suture in total knee arthroplasty (TKA)., Methods: A clinical data of 48 patients with knee osteoarthritis, who underwent initial TKA between January 2017 and April 2018, was retrospectively analyzed. Among them, 23 patients underwent intermittent suture (group A) and 25 patients underwent cosmetic suture (group B). There was no significant difference in gender, age, body mass index, disease duration, degrees of varus and valgus deformities, knee society score (KSS), visual analogue scale (VAS) score, and levels of interleukin-6 (IL-6), procalcitonin (PCT), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) in serum before operation between the two groups ( P >0.05). KSS scores at 1 and 6 months after operation were used to assess the knee function. VAS scores at 1, 3, and 5 days after operation were used to assess the pain degree of knee. Levels of IL-6, PCT, CRP, and ESR in serum at 1 day and 1 month after operation were recorded to evaluate the risk of periprosthetic infection. Likert score at 6 months after operation was used to evaluate the satisfaction of incision. The hospitalization time after operation was also recorded., Results: All patients were followed up 7- 17 months (mean, 11.3 months). There was no significant difference in hospitalization time after operation between two groups ( t =-1.907, P =0.063). The Likert score in group A was significantly lower than that in group B ( t =-2.196, P =0.033). The VAS score, KSS clinical score and KSS functional score at different time points after operation were significantly better than those before operation in two groups ( P <0.05). The VAS score at 5 days after operation was better than that at 1 day after operation in two groups, and the KSS clinical score and KSS functional score at 6 months after operation were better than those at 1 month after operation in two groups, all showing significant differences ( P <0.05). The VAS scores at 3 and 5 days after operation were significantly lower in group B than in group A ( P <0.05), and there was no significant difference in VAS score and KSS scores between two groups at other time points after operation ( P >0.05). There was no significant difference in the levels of IL-6, PCT, CRP, and ESR between the two groups at different time points after operation ( P >0.05)., Conclusion: Cosmetic suture is superior to intermittent suture in incision appearance and pain management, but there is no significant difference in short-term joint function and risk of periprosthetic infection after TKA.

Objective: To evaluate the mid- and long-term effectiveness of total hip arthroplasty (THA) with Ribbed femoral stem prosthesis., Methods: A clinical data of 354 patients (384 hips) with hip disease who underwent THA with Ribbed femoral stem prostheses between October 2006 and May 2016 was retrospectively analyzed. There were 171 males and 183 females, with an average age of 53.4 years (range, 20-82 years). There were 324 cases of single hip and 30 cases of bilateral hips. The cause of THA included the avascular necrosis of the femoral head in 151 cases (159 hips), hip osteoarthritis in 134 cases (136 hips), rheumatoid arthritis in 43 cases (43 hips), ankylosing spondylitis in 20 cases (40 hips), and trauma in 6 cases (6 hips). The Harris score of total 354 patients before operation was 42.34±8.89. Harris scores were used to evaluate hip function after operation. X-ray films were used to determine the length of the lower limb, the radiolucent line on the femur side, the stability of the prosthesis, and the occurrence of stress shielding., Results: The incisions healed by first intention. All patients were followed up 2-11 years with an average of 7.4 years. The Harris score at last follow-up was 80.52±7.61, which significantly increased when compared with preoperative score ( t =134.804, P =0.000). Two cases (2 hips) of prosthetic infections, 3 cases (3 hips) of prothesis loosening, and 4 cases (4 hips) of periprosthetic fractures, and 48 cases (48 hips) of mild to moderate thigh pain occurred after operation. X-ray films showed 76 cases (78 hips) with radiolucent lines on the femur side and stress shielding. According to the Engh's method, there were 364 hips of bone ingrowth, 15 hips of fibrosis ingrowth, and 5 hips of prosthesis instability. The femoral stem subsidence occurred in 25 cases (25 hips), and the difference in leg length discrepancy was more than 10 mm in 5 patients., Conclusion: THA with Ribbed femoral stem prosthesis can achieve satisfactory effectiveness with good initial stability and rapid bone growth. The incidence of stress shielding is relatively high, but the stress shielding has no significant impact on the mid- and long-term survival rate and effectiveness of femoral prosthesis.

Objective: To investigate the short-term effectiveness of total hip arthroplasty with Wagner Cone stem combined with subtrochanteric shortening osteotomy for adult patients with Crowe Ⅳ developmental dysplasia of the hip (DDH)., Methods: A clinical data of 18 patients (20 hips) with Crowe Ⅳ DDH between January 2015 and June 2017 was retrospectively analyzed. There were 5 males (6 hips) and 13 females (14 hips), with an average age of 42 years (range, 20-67 years). There were 18 cases with unilateral DDH and 2 cases with bilateral DDHs. The "4" sign and Trendelenburg sign of affected hip were positive. Preoperative Harris score and visual analogue scale (VAS) score were 41.95±6.90 and 5.05±1.15, respectively. The length discrepancy was (4.76±2.59) cm in patients with unilateral DDH. And the lengths of bilateral lower limbs in patients with bilateral DDH were equal. The acetabular anteversion angle, femoral anteversion angle, and combined anteversion angle were (32.82±2.79), (46.18±6.80), and (79.01±7.54) °, respectively. All patients were treated by total hip arthroplasty with Wagner Cone stem and subtrochanteric shortening osteotomy. The length of osteotomy ranged from 2.0 to 3.5 cm (mean, 2.38 cm)., Results: The operation time was 116-161 minutes (mean, 138.4 minutes); the volume of intraoperative blood loss was 600-1 200 mL (mean, 795 mL); the volume of drainage after operation was 100-630 mL (mean, 252 mL). All incisions healed by first intention. The symptom of sciatic nerve injury occurred in 1 case and relieved after symptomatic treatment. All patients were followed up 12-29 months (mean, 18.4 months). The "4" sign and Trendelenburg sign of affected hip were negative. The Harris score and VAS score at last follow-up were 87.50±5.06 and 0.75±0.85, respectively. The acetabular anteversion angle, femoral anteversion angle, and combined anteversion angle were (16.21±4.84), (18.99±2.55), and (35.20±5.80)°, respectively. There were significant differences in above indexes between pre- and post-operation ( P <0.05). The length discrepancy was (0.72±0.70) cm in patients with unilateral DDH, which was significant shorter than the preoperative value ( t =7.751, P =0.000). And the lengths of bilateral lower limbs in patients with bilateral DDH were equal. X-ray films showed that the osteotomy of femur healed at 3-6 months (mean, 4.1 months) without the signs of loosening, sinking, osteolysis, and dislocation., Conclusion: Total hip arthroplasty with Wagner Cone stem and subtrochanteric shortening osteotomy can obviously improve the hip joint function and restore the length of lower limb. The short-term effectiveness is satisfactory, but the long-term effectiveness and survival rate of prosthesis need to be further observed.

Objective: To evaluate the effectiveness of open arthrolysis in treatment of the patient with stiff knee in late stage after primary total knee arthroplasty (TKA)., Methods: Between January 2014 and October 2017, 7 female patients (7 knees) with stiff knee in late stage after primary TKA were admitted. The patients were 57-71 years old (mean, 63 years). There were 2 left knees and 5 right knees. All patients underwent TKA because of knee osteoarthritis. The interval between TKA and open arthrolysis was 8-30 months (mean, 13.6 months). There were 4 patients with 10-20° of extension deficit before arthrolysis. The range of motion of knee was (54.3±12.1)°. The clinical score, functional score, and total score of Knee Society Score (KSS) before arthrolysis were 76.3±7.6, 67.9±11.1, and 144.1±16.1, respectively. During the arthrolysis, periarticular soft tissue scar was removed, the range of motion of knee was restored, the gap balance and well patellar tracking were maintained. Intensive rehabilitation after operation was supplemented., Results: All wounds healed by first intention, without early stage complications. All patients were followed up 12-32 months with an average of 20.1 months. No abnormality of prosthesis was found by post-operative X-ray films. The knee movement improved significantly when compared with that before arthrolysis. The range of motion was less than 90° in 1 patient and 10° of extension deficit remained in 1 patient after operation. The range of motion was (92.9±4.9)° at last follow-up. The clinical score, functional score, and total score of KSS were 81.9±5.1, 74.3±9.8, and 156.1±13.7, respectively at last follow-up. The above indexes were superior to those before operation ( P <0.05)., Conclusion: Open arthrolysis combined with intensive rehabilitation is a significant way to improve knee function for the patient with stiff knee in late stage after primary TKA.

Joint pain is the defining symptom of osteoarthritis (OA) but its origin and mechanisms remain unclear. Here, we investigated an unprecedented role of osteoclast-initiated subchondral bone remodeling in sensory innervation for OA pain. We show that osteoclasts secrete netrin-1 to induce sensory nerve axonal growth in subchondral bone. Reduction of osteoclast formation by knockout of receptor activator of nuclear factor kappa-B ligand (Rankl) in osteocytes inhibited the growth of sensory nerves into subchondral bone, dorsal root ganglion neuron hyperexcitability, and behavioral measures of pain hypersensitivity in OA mice. Moreover, we demonstrated a possible role for netrin-1 secreted by osteoclasts during aberrant subchondral bone remodeling in inducing sensory innervation and OA pain through its receptor DCC (deleted in colorectal cancer). Importantly, knockout of Netrin1 in tartrate-resistant acid phosphatase-positive (TRAP-positive) osteoclasts or knockdown of Dcc reduces OA pain behavior. In particular, inhibition of osteoclast activity by alendronate modifies aberrant subchondral bone remodeling and reduces innervation and pain behavior at the early stage of OA. These results suggest that intervention of the axonal guidance molecules (e.g., netrin-1) derived from aberrant subchondral bone remodeling may have therapeutic potential for OA pain.

Background: This retrospective study investigated the relative benefits of using a collum femoris-preserving prosthesis or ribbed stem during total hip arthroplasty (THA)., Methods: The clinical results were compared of patients who underwent THA, between January 2010 and December 2012, with either a CFP prosthesis or a ribbed stem (66 and 75 patients, respectively, aged 43.4 ± 10.8 and 42.3 ± 9.8 years). Patients were assessed using the Harris Hip Score (HHS), Western Ontario and McMaster University Osteoarthritis Index (WOMAC), 12-Item Short Form Health Survey (SF-12), and physical component summary (PCS) score. Intraoperative and postoperative complications and leg-length differences were noted., Results: The mean follow-up times of the CFP and ribbed groups were 67.2 ± 7.5 and 68.3 ± 7.2 months, respectively. The HHS, SF-12 MCS, SF-12 PCS, and WOMAC scores of the two groups were similar. The rates of periprosthetic femoral fractures and leg-length differences > 10 mm in the CFP group (10.6% and 13.6%, respectively) were significantly higher than those in the ribbed group (1.3% and 2.7%). The groups were similar regarding complications of osteolysis, ectopic ossification, dislocation, deep infection, deep venous thrombosis, thigh pain, and aseptic loosening. The survival rates of the CFP and ribbed groups were comparable (98.5% and 97.8%)., Conclusion: The clinical results of the CFP and ribbed prostheses in young patients given THA were similar for Chinese patients. However, the CFP stem should be used with caution, given the high incidence of technical problems associated with implantation especially for Chinese patients.

Background: Benefits of yoga practice in patients with knee osteoarthritis and rheumatoid arthritis remains controversial. This study performs a meta-analysis to quantify the efficiency of yoga exercise for patients pain reduction, functional recovery, and general wellbeing., Methods: A computerized search of PubMed and Embase was performed to identify relevant studies. The outcome measures were pain, stiffness, and physical function. Two investigators identified eligible studies and extracted data independently. The quality of citations was measured using Jadad score. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated for pain, musculoskeletal impairment, quality of life, general wellbeing, and mental wellbeing., Results: A total of 13 clinical trials involving 1557 patients with knee osteoarthritis and rheumatoid arthritis were included in final meta-analysis with the average Jadad score 2.8. The SMD was -0.98 (95% CI -1.18, -0.78, P < .05) for pain, -1.83 (95% CI -2.09, -1.57, P < .05) for functional disability, was 0.80 (95% CI 0.59, 1.01, P < .05) for Short Form 36 Health Survey (SF-36) general health, 0.49 (95% CI 0.14, 0.82, P < .05) for SF-36 mental health, and HAQ was -0.55 (95% CI -0.83, -0.26, P < .05) for health associated questionnaire (HAQ). All the results favor yoga training group., Conclusions: Regular yoga training is helpful in reducing knee arthritic symptoms, promoting physical function, and general wellbeing in arthritic patients.

This study evaluated the surgical technique and outcomes of cup revision involving retention of a fixed but malpositioned acetabular component in patients with poor general conditions.Between 2007 and 2013, we performed cup revision on 12 hips while retaining a fixed (either cemented or uncemented) but malpositioned acetabular component. Indications for this technique were: malpositioned but fixed acetabular shell; sufficient space for the insertion of the prosthesis; and patients with poor general conditions. After intraoperative confirmation of shell stability, a replacement liner was oriented in a new plane. Clinical and imaging data were collected perioperatively and during follow-up for evaluation of surgical efficacy.No intraoperative complications were encountered. Mean operative duration was 70.4 minutes (range, 45-90 minutes) and mean estimated blood loss was 729 mL (range, 400-1200 mL). Mean follow-up duration was 5.1 years (range, 2.5-8.5 years). Average visual analog scale score decreased from (7.08 ± 1.00) preoperatively to (1.42 ± 0.67) at final follow-up (P < .05). Average Harris Hip Score improved from (14.7 ± 6.58) preoperatively to (80.9 ± 5.30) at final follow-up (P < .05). Anteversions and inclinations of new liners were (15.1 ± 2.3)° and (46.4 ± 3.9)° respectively. Postoperative radiographs showed no signs of prosthesis loosening, periprosthetic fractures, or dislocation compared with preoperatively.The short-term efficacy of cup revision with retention of a malpositioned but fixed acetabular component was satisfactory.

Near-infrared (NIR) laser-induced photothermal therapy (PTT) uses a photothermal agent to convert optical energy into thermal energy and has great potential as an effective local, minimally invasive treatment modality for killing cancer cells. To improve the efficacy of PTT, we developed poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) encapsulating superparamagnetic iron oxide (Fe 3 O 4 ), indocyanine green (ICG), and perfluoropentane (PFP) as synergistic agents for NIR laser-induced PTT. We fabricated a novel type of phase-shifting fluorescent magnetic NPs, Fe 3 O 4 /ICG@PLGA/PFP NPs, that effectively produce heat in response to NIR laser irradiation for an enhanced thermal ablation effect and a phase-shift thermoelastic expansion effect, and thus, can be used as a photothermal agent. After in vitro treatment of MCF-7 breast cancer cells with Fe 3 O 4 /ICG@PLGA/PFP NPs and NIR laser irradiation, histology and electron microscopy confirmed severe damage to the cells and the formation of many microbubbles with iron particles at the edge or outside of the microbubbles. In vivo experiments in mice with MCF-7 tumors demonstrated that Fe 3 O 4 /ICG@PLGA/PFP NPs could achieve tumor ablation upon NIR laser irradiation with minimal toxicity to non-irradiated tissues. Together, our results indicate that Fe 3 O 4 /ICG@PLGA/PFP NPs can be used as effective nanotheranostic agents for tumor ablation.

Background: Women's parity has been associated with risk of cardiovascular disease (CVD). It is unclear, however, whether it reflects biological effects of childbearing or uncontrolled socio-economic and lifestyle factors associated with childrearing. We assessed the association between number of children and incident CVD outcomes separately in women and men., Methods: In 2004-08, the nationwide China Kadoorie Biobank recruited 0.5 million individuals aged 30-79 years from 10 diverse regions. During 7 years of follow-up, 24 432 incident cases of coronary heart disease (CHD) and 35 736 of stroke were recorded among 489 762 individuals without prior CVD. Multivariable Cox regression models were used to estimate sex-specific hazard ratios (HRs) and 95% confidence intervals (CIs) for CHD and stroke associated with number of children., Results: Overall, 98% of all participants had children and the mean number of children declined progressively from four in older participants to one or two in younger participants. Compared with childless women, women with children had an increased risk of CHD, but not of stroke [HR (95% CI): 1.14 (1.00; 1.30) and 1.03 (0.92; 1.16)]. Corresponding results for men were 1.20 (1.06; 1.35) and 1.13 (1.03; 1.24), respectively. In individuals with children, there was a log-linear association between number of children and CVD outcomes; in women, each additional child was associated with adjusted HRs of 1.02 (1.01; 1.04) for CHD and 1.02 (1.01; 1.03) for stroke, similar in magnitude to that in men [1.03 (1.01; 1.04) for CHD and 1.02 (1.01; 1.03) for stroke]., Conclusion: In Chinese adults, the association between the number of children and risk of CHD and stroke was similar between men and women, suggesting that factors associated with parenthood and childrearing are more likely to affect the risk of CVD outcomes than factors associated with childbearing., (© The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association)

Objective: To evaluate the short-term effectiveness of minimally invasive total hip arthroplasty (THA) by direct anterior approach (DAA)., Methods: Between January and August 2014, THA was performed on 48 patients (60 hips) by DAA (group A), and on 72 patients (92 hips) by posterolateral approach (group B). There was no significant difference in gender, age, etiology, course, and preoperative visual analogue scale (VAS), Harris hip score (HHS), and hip range of motion (ROM) between 2 groups ( P >0.05). The operation time, intraoperative blood loss, postoperative drainage, hospitalization time, incision healing, and complications were recorded and compared. The acetabular abduction and anteversion were measured on the X-ray films; prosthesis loosening was observed. The VAS score, HHS score, and hip ROM were used to evaluate the hip function., Results: The operation time and intraoperative blood loss of group A were significantly higher than those of group B, and the hospitalization time was significantly lower than group B ( P <0.05), but no significant difference was found in postoperative drainage between 2 groups ( t =0.71, P =0.46). The patients were followed up 2-2.5 years (mean, 2.2 years) in group A, and 2-2.5 years (mean, 2.1 years) in group B. In group A, 3 cases had lateral femoral cutaneous nerve traction injury and 1 case had swelling and exudate, and primary healing of incision was obtained in the other cases of group A and all cases of group B. No periprosthetic joint infection occurred in the others of groups A and B except 1 case of group A at 2 months after operation, and infection was controlled after debridement, irrigation, and intravenous infusion of Vancomycin for 1 month. The X-ray films showed good position of prosthesis and no obvious radiolucent line or prosthesis loosening. There was no significant differences in acetabular abduction and anteversion between groups A and B at last follow-up ( P >0.05). The VAS score, HHS score, and hip ROM at 3 months and last follow-up were significantly better than preoperative ones in 2 groups ( P <0.05), but no significant difference was found between at 3 months and last follow-up ( P >0.05). The VAS score, HHS score, and hip ROM in group A were significantly better than those in group B at 3 months postoperatively ( P <0.05). At last follow-up, the hip ROM in group A was significantly better than that in group B ( P <0.05), and there was no significant difference in VAS and HHS scores between group A and group B ( P >0.05)., Conclusion: The short-term effectiveness of minimally invasive THA by DAA is satisfactory, with the advantage of little trauma, short hospital stay, and rapid postoperative recovery.

The aim of the present study was to examine hypoxia-inducible factor 1α (HIF-1α) levels in the synovial fluid and articular cartilage of patients with primary knee osteoarthritis (OA) and to investigate their association with the severity of disease. A total of 36 patients with knee OA and ten healthy controls were enrolled. Anteroposterior knee radiographs and/or Mankin scores were assessed to determine the disease severity of the affected knee. Radiographic grading of OA in the knee was performed according to Kellgren-Lawrence criteria. HIF-1α levels in synovial fluid were measured using enzyme-linked immunosorbent assay, whereas HIF-1α levels in articular cartilage were assessed with immunohistochemical methods. Compared with healthy controls, OA patients exhibited an increased HIF-1α concentration in synovial fluid (218.17±25.12 vs. 156.66±7.74 pg/ml; P<0.001) and articular cartilage (P<0.05). Furthermore, synovial fluid HIF-1α levels demonstrated a positive correlation with articular cartilage HIF-1α levels (Pearson's P=0.815; P<0.001). Subsequent analysis showed that synovial fluid HIF-1α levels were significantly correlated with the severity of disease (Spearman's ρ=0.933; P<0.001). Furthermore, articular cartilage levels of HIF-1α also correlated with disease severity (Spearman's ρ=-0.967; P<0.001). The findings of the present study suggested that HIF-1α in synovial fluid and articular cartilage is associated with progressive joint damage and is likely to be a useful biomarker for determining disease severity and progression in knee OA.

Objective: To investigate the clinical effect of total knee arthroplasty on patients with knee osteoarthritis combined with mild to moderate valgus knee deformity.
, Methods: A total of 15 patients received total knee arthroplasty for correcting mild (10°-15°) to moderate (15°-30°) valgus knee between January 2011 and February 2014 in Xiangya Hospital of Central South University. We adopted a stable prosthesis surgery through patellar medial approach, osteophytes cleaning, conventional osteotomy, a selective soft tissue release and balance technical correcting of knee valgus deformity. Then conventional anticoagulation and symptomatic rehabilitation was utilized. Preoperative and postoperative X-ray was conducted in patients with measuring femor-tibial angle (FTA) and inspecting the prosthesis position. FTA, visual analog scale (VAS) standard, and parallel knee scoring system (KSS) were used to evaluate the clinical effect.
, Results: Fifteen patients were followed up for 14 to 36 (22.40±11.88) months. The hospitalization time was 7-13 (7.73±1.58) d; operative time was 58-110 (81.8±16.85) min, the dominant blood loss was 140-600 (337.30±143.65) mL. Two cases had knee extension hysteresis, and the knee activity recovered after exercise. Leg power lines were normal. Three postoperative cases suffered anterior knee pain. They were subjected to celecoxib analgesic treatment and the pain gradually eased after 3 months. One postoperative case showed incision discharge and swelling, which was healed after change of dressing. During follow-up, review of X-ray film does not show prosthesis loose, subsidence and other complications. The knee valgus angle (8.1±1.8)°, knee motion range (107.33±9.61)°, KSS knee score (74.7±14.5, 75.3±2.7) and pain score (2.5±0.9) were significantly better than the preoperative (P<0.05). The clinical and function KSS scores showed that the improvement rate was 80%. 
, Conclusion: Total knee arthroplasty is an effective way to treat patients with knee osteoarthritis combined with mild to moderate valgus knee deformity. The correction of deformity and improvement of joint function can be achieved significantly. The clinical result is satisfactory and patients' quality of life is improved.

Phosphatidylinositol‑3,4,5‑trisphosphate‑dependent Rac exchange factor 2a (PREX2a), which is a regulator of the small guanosine triphosphatase Rac, has recently been reported to have an oncogenic role via the suppression of phosphatase and tensin homolog deleted on chromosome ten (PTEN) activity, and the subsequent activation of phosphoinositide 3‑kinase (PI3K) signaling. However, the detailed role of PREX2a in osteosarcoma (OS) remains unclear. Reverse transcription quantitative polymerase chain reaction and western blotting was used to detect mRNA and protein levels. MTT assay was performed to examine cell proliferation and a Transwell assay and wound healing assay were conducted to examine cell invasion and migration. The present study demonstrated that PREX2a was markedly upregulated in OS cell lines, as compared with in normal osteoblast hFOB1.19 cells. In addition, knockdown of PREX2a expression significantly inhibited OS cell proliferation, whereas overexpression of PREX2a markedly promoted OS cell proliferation. Inhibition of PREX2a also markedly suppressed the invasion and migration of OS cells, at least partly by suppressing the protein expression of matrix metalloproteinase (MMP)2 and MMP9. Conversely, upregulation of PREX2a enhanced OS cell invasion and migration. In addition, PI3K signaling activity was significantly reduced following knockdown of PREX2a, and this was accompanied by an upregulation of PTEN activity. The results of the present study suggested that PREX2a may act as an oncogene in OS via the inhibition of PTEN activity and activation of PI3K signaling.

Objective: To evaluate the effectiveness of reduction osteotomy for correction of varus knee during total knee arthroplasty., Methods: A retrospective analysis was made on the clinical data of 16 patients (24 knees) who received reduction osteotomy for correcting varus knee during total knee arthroplasty between May 2010 and July 2012. There were 2 males (3 knees) and 14 females (21 knees), with an average age of 67 years (range, 57-79 years). The disease duration ranged from 3 to 15 years (mean, 9.1 years). The Knee Society Score (KSS) was 38.71 ± 10.04 for clinical score and 50.31 ± 14.31 for functional score. The range of motion (ROM) of the knee was (91.88 ± 13.01). The tibiofemoral angle was (9.04 ± 4.53)° of varus deformity. Reduction osteotomy was applied to correct varus knee., Results: The operation time was 85-245 minutes (mean, 165.5 minutes); the obvious blood loss was 10-800 mL (mean, 183.1 mL); the hospitalization time was 8-22 days (mean, 13.6 days). All incisions healed by first intention. No neurovascular injury or patellar fracture occurred. The follow-up duration ranged from 37 to 62 months (mean, 48 months). The tibiofemoral angle was corrected to (3.92 ± 1.89)° of valgus at 48 hours after operation. The lower limb alignment recovered to normal. The X-ray films showed no evidence of obvious radiolucent line, osteolysis, or prosthesis subsidence. The results of KSS were significantly improved to 84.21 ± 6.49 for clinical score and 85.31 ± 6.95 for functional score (t = 20.665, P = 0.000; t = 9.585, P = 0.000); and ROM of the knee was significantly increased to (105.83 ± 11.29)° (t = 8.333, P = 0.000) at last follow-up., Conclusion: The effectiveness of reduction osteotomy for varus knee deformity during total knee arthroplasty is satisfactory. Proper alignment, ROM, and function of knee can be achieved.

Introduction: Whether the expression level of MMP-1, MMP-13 and TIMP-1 has association with the degeneration of lateral meniscus after posterior cruciate ligament (PCL) fracture is poorly understood. The aim of this study was to investigate the influence of PCL fracture on lateral meniscus, including morphological changes, histological changes and roles of matrix metalloproteinase-1 (MMP-1), matrix metalloproteinase-13 (MMP-13) and tissue inhibitor of metalloproteinase-1 (TIMP-1) expression level in the secondary injury., Materials and Methods: Sixty male rabbits were used as PCL transection models and randomized into the PCL-transection side, which underwent PCL transection surgery, and the control side, which underwent PCL exposure without transection. On 4, 8, 12, 16 and 24 weeks after PCL-transection, 12 rabbits were randomly killed for H&E staining to determine the histological changes of lateral meniscus. Immunohistochemical staining was undertaken to evaluate the expression level of MMP-1, MMP-13 and TIMP-1 in lateral meniscus. The results were statistically analyzed using SPSS 15.0., Results: The lateral meniscus of PCL-transection side presented abnormal morphology. Histological evaluation score of meniscal degeneration in PCL-transection group was higher than that in the control group with statistical difference (P < 0.05). The expression levels of MMP-1, MMP-13 and TIMP-1 were significantly elevated in meniscus of the PCL-transection group with statistical difference (P < 0.05). MMP-1 expression displayed an increasing trend firstly then kept stable after PCL transection; MMP-13 and TIMP-1 expression displayed high level firstly then decreased in advanced stage after PCL transection., Conclusions: PCL transaction may induce a coordinated response of degeneration of lateral meniscus in a time-dependent manner. The high expression level of MMP-1, MMP-13 and TIMP-1 would contribute to the degeneration of lateral meniscus after PCL transection.

Objective: This study aims to investigate the biomechanical effect of posterior cruciate ligament (PCL) rupture on lateral meniscus., Method: The stresses of anterior horn, caudomedial part and posterior horn of lateral meniscus in cadaveric knees were recorded when the knee joints were loaded 200 to 1000 N at 0, 30, 60 and 90° of flexion. Twelve knees were tested before PCL transection (intact group), and 6 each were then tested after anterolateral bundle (ALB group) and postmedial bundle (PMB group) transection. The same knees were finally tested after complete PCL transection., Result: At 0°of knee flexion, the stresses of the anterior horn, caudomedial part and posterior horn were negative and compressive, and were not significantly different between intact and ALB groups, and between completely transected and PMB groups at 200 and 400 N. The stresses of the anterior horn and caudomedial part were greater in completely transected and PMB groups than in intact and ALB groups. The stresses of the posterior horn were smaller in PMB and completely transected groups than in intact and ALB groups. At 600-1000 N, the stresses were significantly different between the groups. The absolute stresses of the anterior horn and caudomedial part were in order of completely transected > PMB > ALB > intact group, while these of the posterior horn were reversed. At 30° of knee flexion, the stresses of the three parts were not significantly different between intact and PMB groups nor between completely transected and ALB groups at 200 and 400 N. The stresses in the anterior horn and caudomedial part were negative and different between completely transected and ALB groups, and positive and different between intact and PMB groups. The stresses in the posterior horn were positive and different between completely transected and ALB groups, and negative and different between intact and PMB groups. At loads of > 600 N, the stresses in the anterior horn and caudomedial part were negative in completely transected and ALB groups, and positive in intact and PMB groups. The stresses of the posterior horn were positive in completely transected and ALB groups and negative in intact and PMB groups, with significant difference between the groups. At 60° and 90° of flexion, the stresses of the anterior horn and caudomedial part were positive in completely transected and ALB groups and positive in intact and PMB groups, while the stresses of posterior horn were in the opposite directions and were significantly different between the groups at the same loads., Conclusion: Complete transection of PCL will result in stress changes in various parts of lateral meniscus. At 200 and 400 N, transection of ALB and PMB do not change the stress at 0° and 30° of flexion, respectively. At heavier loads (600-1000 N), the stresses at these angels are affected in ALB and PMB groups. At all loaded tested, transection of ALB and PMB results in changed stresses in all regions of lateral meniscus at 30-90° and 0-90° of flexion, respectively.

Objective: To assess the effectiveness of two osteotomy methods in total hip arthroplasty (THA) for treating Crowe type IV adult developmental dysplasia of the hip (DDH), trochanteric osteotomy and subtrochanteric osteotomy., Methods: A retrospective analysis was made on the clinical data of 36 patients (43 hips) with Crowe type IV DDH undergoing THA between June 2007 and December 2013. In THA, 19 patients (23 hips) underwent trochanteric osteotomy (group A) and 17 patients (20 hips) underwent subtrochanteric osteotomy (group B). There was no significant difference in age, gender, body mass index, side, preoperative Harris score, and limb length difference between 2 groups (P>0.05). The operation duration, bleeding volume, hospitalization duration, intraoperative and postoperative complications were compared between 2 groups., Results: There was no significant difference in operation duration, bleeding volume, and hospitalization days between 2 groups (P>0.05). The rate of intraoperative complication was 21.7% (5/23) in group A and 5.0% (1/20) in group B, showing no significant difference between 2 groups (P>0.05). The rate of postoperative complications was 10.5% (2/19) in group A and 22.2% (4/18) in group B, showing no significant difference between 2 groups (P>0.05). Thirty-one patients (37 hips) were followed up 1-7 years (mean, 3 years), including 16 cases (19 hips) in group A and 15 cases (18 hips) in group B. X-ray films showed good position of the prostheses. The Harris score at last follow-up was significantly increased when compared with preoperative score in 2 groups (P<0.05), but there was no significant difference between 2 groups (P>0.05). The postoperative discrepancy of bilateral lower limbs had no significant difference (t = -1.343, P=0.188)., Conclusion: THA with trochanteric osteotomy or subtrochanteric osteotomy both can effectively treat Crowe type IV DDH. THA with subtrochanteric osteotomy has an advantage in correcting lower limb discrepancy.

Ankylosing spondylitis is a chronic inflammatory rheumatic disease, which is characterized by inflammation of the spine and the sacroiliac joints. To date, the disease etiology remains unclear. In the present study, the correlation of T lymphocyte subset changes with the progression of ankylosing spondylitis was investigated. A total of 55 patients with ankylosing spondylitis (22 severe and 23 mild cases) and 20 healthy individuals were selected. Firstly, the punctured cells in the lesions and the serum were collected, and the lymphocytes and the peripheral blood mononuclear cells were prepared. Secondly, quantitative PCR, ELISA and flow cytometry analyses were carried out to detect the levels of a series of immunoglobulins, complements, helper T cells, cytotoxic T cells, regulatory cells and cytokines. The expression levels of α-globulin, γ-globulin, immunoglobulin (Ig)G, IgA, IgM, serum complement C3, and complement C4 were found to be significantly increased in ankylosing spondylitis patients. In addition, the percentage of Th1 and Th17 cells was found to be significantly higher in the ankylosing spondylitis groups (mild and severe) compared with the healthy individuals. As a result, the Th1/Th2 and Th17/Treg ratios were significantly higher in patients with ankylosing spondylitis. In addition, T lymphocyte subset ratio imbalances contributed to an increased expression of immune mediators, including interferon (IFN)-γ and interleukin (IL)-17A. The mRNA and protein expression levels of IFN-γ and IL-17A were found to be higher in the ankylosing spondylitis groups compared with the control group. The present study provided further evidence on the function and underlying mechanism of T lymphocyte subsets, which may be useful in the diagnosis and treatment of ankylosing spondylitis.

Objective: To explore the relationships between anthropometric measures as body mass index (BMI), percentage body fat, waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and the risks of diabetes., Methods: We analyzed the baseline data of 53 260 participants who were aged 30-79 years and had been enrolled into the China Kadoorie Biobank (CKB) study from Suzhou city,Jiangsu province. Unconditional logistic regression analyses were conducted with adjustment for potential confounders., Results: Overall, 5.3% of the participants had diabetes, with about a half of them being newly detected through on-site screening tests. The prevalence of diabetes increased with age, 61% higher (OR = 1.61, 95% confidence interval: 1.54-1.67) risk of diabetes, with 10 years increase of age. In both genders, all anthropometric measures were positively and significantly associated with diabetes, with the associations of measures in central adiposity stronger than those in general obesity, with WHR as the strongest. Each standard deviation (1- s) with greater WHR (<0.06 in men and 0.07 in women) was associated with 72% (61%-83%) higher risk of diabetes in men and 93% (83%-102%) in women. After adjusting for HC, each WC with 5 cm larger, showing 65% and 57% higher risks in men and women respectively. However, after adjusting for WC, every 5cm greater HC appeared and associated with respective 38% and 34% lower risks., Conclusion: Measures on adiposity including BMI, percentage body, WC, WHR and WHtR fat were all positively associated with the prevalence of diabetes. Measures of central obesity, particularly WHR, were more strongly associated with diabetes than measures of general obesity. When WC was under control, HC appeared inversely associated with diabetes.

Objective: To explore the feasibility of three-dimensional (3-D) visualization reconstruction of the medial sural artery perforator flap based on digital technology., Methods: A series of Dicom images were obtained from three healthy adult volunteers by dual source CT angiography. Then the Mimics software was used to construct the medial sural artery model and measure the indexes, including the starting position of medial sural artery, external diameters of vascular pedicle, the number of perforators, location perforated deep fascia, and the maximum pedicle length of perforators based on medial sural artery perforator flap., Results: The 3-D visualization reconstruction models were successfully finished with Mimics software, which can clearly display the distribution, travel, and perforating point. Thirteen perforators were found in 6 legs, which started at the popliteal artery with a mean external diameter of 2.3 mm (range, 1.9-2.7 mm). Each specimen had 1-3 perforators, which located at the site of 6.2-15.0 cm distal to popliteal crease and 2.5-4.2 cm from posterior midline. The maximum pedicle length of medial sural artery perforator flap was 10.2-13.8 cm (mean, 11.8 cm)., Conclusion: The 3-D visualization reconstruction models based on digital technology can provide dynamic visualization of the anatomy of the medial sural artery for individualized design of the medial sural artery perforator flap.

Background: Despite the great burden of chronic respiratory diseases in China, few large multicentre, spirometry-based studies have examined its prevalence, rate of underdiagnosis regionally or the relevance of socioeconomic and lifestyle factors., Methods: We analysed data from 512 891 adults in the China Kadoorie Biobank, recruited from 10 diverse regions of China during 2004-2008. Air flow obstruction (AFO) was defined by the lower limit of normal criteria based on spirometry-measured lung function. The prevalence of AFO was analysed by region, age, socioeconomic status, body mass index (BMI) and smoking history and compared with the prevalence of self-reported physician-diagnosed chronic bronchitis or emphysema (CB/E) and its symptoms., Findings: The prevalence of AFO was 7.3% in men (range 2.5-18.2%) and 6.4% in women (1.5-18.5%). Higher prevalence of AFO was associated with older age (p<0.0001), lower income (p<0.0001), poor education (p<0.001), living in rural regions (p<0.001), those who started smoking before the age of 20 years (p<0.001) and low BMI (p<0.001). Compared with self-reported diagnosis of CB/E, 88.8% of AFO was underdiagnosed; underdiagnosis proportion was highest in 30-39-year olds (96.7%) compared with the 70+ age group (81.1%), in women (90.7%), in urban areas (89.4%), in people earning 5K-10 K ¥ monthly (90.3%) and in those with middle or high school education (92.6%)., Interpretation: In China, the burden of AFO based on spirometry was high and significantly greater than that estimated based on self-reported physician-diagnosed CB/E, especially in rural areas, reflecting major issues with diagnosis of AFO that will impact disease treatment and management.

Objective: The aim of this study was to evaluate the clinical and radiological outcomes and complications of total hip arthroplasty (THA) using the collum femoris preserving (CFP) prosthesis., Methods: The study included the 142 hips of 125 patients (mean age: 50 years; range: 38 to 60 years) who underwent THA with CFP prosthesis between January 2004 and December 2011. There were 70 males (82 hips) and 55 females (60 hips). Patients were assessed using the Harris hip score (HHS) and visual analog scale (VAS). Radiographs were evaluated according to the Gruen zones and DeLee and Charnley zones to assess the prosthesis position, loosening and ectopic ossification., Results: Follow-up was obtained over 4.72 ± 2.16 (range: 1 to 8.4) years and no patients were lost to follow-up. Mean HHS improved from 51.43 ± 4.14 points preoperatively to 90.27 ± 6.60 points postoperatively, while VAS scores decreased from 8.3 ± 3.12 to 2.1 ± 1.54 by the final review. The HHS revealed excellent and good results in 87.4% of patients. Mild ectopic ossification occurred in 4 cases (2.8%), which were all Grade 1 according to the Brooker classification and without clinical symptoms. In 5 cases (3.5%), bone loss was found in the proximal femur. Radiolucent lines surrounding the stem were not observed in any case. There was no prosthesis loosening or femoral prosthesis subsidence. The survival rate was 100% for the femoral and acetabular components. Ten fractures (7%) of the lateral femoral diaphysis at the tip of the stem occurred during surgery and none of these required additional treatment. No infection, dislocation or deep vein thrombosis was observed., Conclusion: Total hip arthroplasty with CFP prosthesis appears to be a good option for young patients for a variety of etiologies but close attention should be paid to the prevention of complications.

Objective: To evaluate the mid-term effectiveness of rotating hinge knee prosthesis for severe knee deformity., Methods: A retrospective analysis was made on the clinical data of 24 patients (24 knees) who received rotating hinge knee prosthesis for total knee arthroplasty between January 2003 and June 2011. There were 14 males and 10 females, aged from 60 to 81 years (mean, 70 years). The disease causes included osteoarthritis in 5 cases, rheumatoid arthritis in 7 cases, traumatic arthritis in 9 cases, and Charcot's arthropathy in 3 cases. The disease duration ranged from 5 to 25 years (mean, 14.5 years). Of them, 13 cases had flexion deformity, 7 cases had valgus deformity, and 16 cases had varus deformity. The operation time, the amount of bleeding between operation and drainage-tubes removal, hospitalization time, incision healing, and complications were recorded. The results were evaluated according to Knee Society Score (KSS), visual analogue scale (VAS), and the range of motion (ROM) of knee. Short-form 36 health survey scale (SF-36) was used to evaluate the life quality of patients. The position of prosthesis was observed through X-ray examination., Results: The operation time ranged from 70 to 90 minutes (mean, 78 minutes). The amount of bleeding between operation and drainage-tubes removal ranged from 400 to 1 000 mL (mean, 650 mL). The hospitalization time ranged from 14 to 18 days (mean, 15.2 days). Patellar fracture occurred in 1 case (4.17%) during operation, swelling and effusion of incision in 1 case (4.17%), and periprosthetic infections in 2 cases (8.33%) after operation. All patients were followed up 2-10 years (mean, 5.5 years). The X-ray films showed no evidence of obvious radiolucent line, osteolysis, prosthesis subsidence, and limb alignment change. The results of KSS, VAS socres, and ROM of knee at 1 year postoperatively and last follow-up were significantly better than preoperative ones (P < 0.05), but no significant difference was found between at 1 year postoperatively and last follow-up (P > 0.05). The physiological function and body pain scores were significantly lower than the reference value of urban men over 60 years old from Sichuan province (t = 2.42, P = 0.02; t = 5.26, P = 0.00), but no significant difference was found in the other scores of the SF-36 when compared with the reference value (P > 0.05)., Conclusion: The mid-term effectiveness of total knee arthroplasty using rotating hinge knee for severe knee prosthesis deformity is satisfactory. But complications of postoperative infection should be emphasized.

Objective: To investigate the effectiveness of two-stage revision of infected total knee arthroplasty (TKA) using an antibiotic-impregnated articulating cement spacer., Methods: The clinical data were analyzed from 23 patients (23 knees) undergoing two-stage revision for late infection after primary TKA between January 2007 and December 2009. There were 15 males and 8 females, aged from 43 to 75 years (mean, 65.2 years). Infection occurred at 13-52 months (mean, 17.3 months) after TKA. The time interval between infection and admission ranged from 15 days to 7 months (mean, 2.1 months). One-stage operation included surgical debridement and removal of all knee prosthesis and cement, then an antibiotic-impregnated articulating cement spacer was implanted. The re-implantation of prosthesis was performed after 8-10 weeks when infections were controlled. The American Hospital for Special Surgery (HSS) score and Knee Society Score (KSS) were used to compare the function of the knee between pre- and post-revision. The rate of infection control and complication were analyzed., Results: All incisions healed primarily. Re-infection occurred in 2 cases after two-stage revision, and infection was controlled in the other 21 cases, with an infection control rate of 91.3%. The patients were followed up 2-5 years (mean, 3.6 years). The HSS score was increased from 60.6 +/- 9.8 at pre-revision to 82.3 +/- 7.4 at last follow-up, the KSS score was increased from 110.7 +/- 9.6 at pre-revision to 134.0 +/- 10.5 at last follow-up, all showing significant differences (P < 0.01). Radiographs showed that prosthesis had good position with no loosening, fracture, or periprosthetic radiolucent., Conclusion: Two-stage revision using an antibiotic-impregnated articulating cement spacer is an effective method to control infected TKA and to restore the function of affected knee.

Objective: To discuss the clinical application of total hip arthroplasty (THA) with collum femoris preserving (CFP) prosthesis and to analyze the mid-term effectiveness., Methods: Between January 2004 and February 2007, 45 patients (48 hips) underwent THA with CFP prosthesis. There were 29 males (31 hips) and 16 females (17 hips) with an average age of 48.8 years (range, 38-60 years), including 20 left hips, 22 right hips, and 3 bilateral hips. The causes of hip replacement were osteoarthritis (20 cases), avascular necrosis of femoral head (13 cases), dysplasia (4 cases), rheumatoid arthritis (3 cases), posttraumatic osteoarthritis (2 cases), ankylosing spondylitis (2 cases), and Perths disease (1 case). The average disease duration was 6.1 years (range, 2-13 years). Harris scores, visual analogue scale (VAS) score, and the hip range of motion (ROM) were recorded at pre- and post-operation. The X-ray films were taken at pre- and post-operation to observe the position, loosening of the prosthesis, and ectopic ossification. The gait of patients were also evaluated during follow-up. Short-form 36 health survey scale (SF-36) was used to evaluate the life quality of patients., Results: All 45 patients were followed up 5-8 years with an average of 6.4 years. All the incisions healed by first intention. No infection, hip dislocation, nerve injury, or deep vein thrombosis occurred. Six cleavage fractures (13.3%) of the lateral femoral diaphysis at the distal prosthesis occurred during operation, which healed at 8 months postoperatively without any treatment. Mild ectopic ossification occurred in 4 patients (8.9%) who had no discomfort. Five patients (11.1%) had bone mineral density loss in the region of the proximal femur. The survival rates of the cups and stems were all 100% at last follow-up. The results of Harris score, VAS score, and ROM of the hip joint at 1 year postoperatively and last follow-up were significantly better than preoperative ones (P < 0.05). No significant difference was found in VAS score and ROM of the hip joint between at 1 year postoperatively and at last follow-up (P > 0.05) except the Harris score (P < 0.05). According to Harris functional assessment at last follow-up, the results were excellent in 31 hips, good in 11 hips, and fair in 6 hips with an excellent and good rate of 87.5%. The physiological role, body pain, and total health scores were significantly lower than the reference value of urban men from Sichuan province (P < 0.05), but no significant difference was found in the other scores of the SF-36 when compared with the reference value (P > 0.05)., Conclusion: THA with CFP prosthesis is a good option for the young patient with complete collum femoris and without osteoporosis, and can achieve good mid-term effectiveness.

Objective: To explore the difference in level of pain experienced by patients with total hip arthroplasty between aseptic loosening and periprosthetic infection, and to examine the correlation between C-reactive protein (CRP) and pain., Methods: Fifty-one patients (recruited from our hospital between March 2010 and November 2011) suffering aseptic loosening or periprosthetic infection after total hip arthroplasty were included in this study: 24 males and 27 females, with mean age 68.13 years. The patients were divided into an aseptic loosening group (n=31) and a periprosthetic infection group (n=20). Both the visual analog scale (VAS) and Harris pain score were used to estimate the level of pain experienced by the patients. CRP levels in serum were measured. The difference in assessment of pain by VAS and Harris pain score was compared between the two groups, and the correlation between pain and CRP was analyzed., Results: The mean VAS in the aseptic loosening group was 5.39 (2.10-8.13) compared with 5.48 (2.09-8.30) in the periprosthetic infection group; however, the difference was not statistically significant (P=0.85). The mean rank of Harris pain score was 26.23 in the aseptic loosening group and 25.65 in the periprosthetic infection group, but again there was no significant difference (P=0.88). The CRP level in the periprosthetic infection group (36.20-101.40 mg/L, mean 72.86 mg/L) was obvious higher than that in the aseptic loosening group (1.37-13.70 mg/L, mean 6.53 mg/L), and the difference was statistically significant (P<0.01). The VAS was related with the CRP level in the periprosthetic infection group (r=0.87, P<0.01), and the correlation between Harris pain score and CRP level was conspicuous (r=0.92, P<0.01) in this group. However, those correlations were not evident in the aseptic loosening group (r=0.25, P=0.17; r=0.19, P=0.65)., Conclusion: There is no difference in perception of pain in patients after total hip arthroplasty between those with aseptic loosening and those with periprosthetic infection. It is therefore unreliable to make a initial diagnosis only according to the level of pain. However, the level of CRP is a sensitive and effective way of differentiating the two conditions. The positive correlation between CRP and pian exists in patients with periprosthetic infection but not with aseptic loosening.

Objective: To analyze the main reasons of acetabular component initial instability after primary total hip arthroplasty (THA) and to discuss the prevention and management., Methods: The clinical data were retrospectively analyzed from 19 patients undergoing revision for acetabular component initial instability after primary THA between January 2003 and June 2010. There were 11 males and 8 females, aged from 55 to 79 years (mean, 67.2 years). The locations were left hip in 9 cases and right hip in 10 cases. The cementless hip prosthesis was used in 12 cases and cement hip prosthesis in 7 cases. The revisions were performed at 3 weeks to 6 months after primary THA. The reasons of early failure were analyzed. Both the coverage rate of acetabulum-bone and the Harris hip score were compared between pre- and post-revision., Results: The main reason of acetabular component initial instability after primary THA may be unsuitable treatment of acetabulum, improper selection of acetabular component, and incorrect place angle of acetabular component. Sciatic nerve palsy occurred in 1 case and recovered at 7 weeks after revision. Slight fracture of the acetabulum in 1 case and healed at 3 months after revision. All incisions healed by first intention. No infection, vessel injury, displacement of acetabular component, or deep vein thrombosis occurred. The patients were followed up 11-73 months (mean, 28 months). At last follow-up, no acetabular component instability was observed. The coverage rate of acetabulum-bone was increased from 67.9% +/- 5.5% before revision to 87.7% +/- 5.2% after revision, showing significant difference (t = 11.592, P = 0.003). The Harris hip score at last follow-up (84.4 +/- 4.6) was significantly higher than that at pre-revision (56.5 +/- 9.3) (t = 11.380, P = 0.005)., Conclusion: Detailed surgical plan, proper choice of component, correct place angle and elaborative planning, and proficient surgical skill are necessary to achieve the initial stability of acetabular component in THA.

Objective: To evaluate the mid-term effectiveness of two-stage hip prosthesis revision in the treatment of infection after hip arthroplasty., Methods: Between April 2002 and November 2006, 12 cases of infection after hip arthroplasty were treated. There were 5 males and 7 females, aged from 47 to 72 years (mean, 59.8 years). The femoral head arthroplasty was performed in 2 cases and total hip arthroplasty in 10 cases. Infection occurred 1 to 67 months after arthroplasty. According to the Segawa classification criteria, infections included type 2 in 1 case, type 3 in 2 cases, and type 4 in 9 cases. The preoperative Harris score was 36.7 +/- 6.1. Nine cases had elevated C reactive protein and 10 cases had elevated erythrocyte sedimentation rate. The results of bacterial culture were positive in 8 cases and negative in 4 cases. After the removal of the infected prosthesis and thorough debridement, antibiotic-loaded cement spacers or infected therapeutic temporary prosthesis were used as placeholders, and then the anti-infection treatments were given after operations; two-stage hip prosthesis revisions were performed 3 to 10 months after debridement., Results: In 1 patient who failed to control infection after debridement, infection was controlled after the second debridement and the antibiotic-loaded cement spacer as placeholder. Other patients achieved healing of incision by first intention, and no complication such as deep venous thrombosis and nerve injury occurred. All patients were followed up 3 to 8 years after revision (mean, 5.4 years). During the follow-up, no infection recurrence and joint dislocation occurred. Dull pain was present in 2 cases during activity and mild claudication in 3 cases at last follow-up. The Harris score was 81.6 +/- 4.5, showing significant difference (t = 52.696, P = 0.000) when compared with preoperative score. The X-ray films showed that no prosthesis loosening and obvious subsidence were observed, and bone graft healed., Conclusion: The two-stage hip prosthesis revision has good infection control rate and mid-term effectiveness in treatment of infection after hip arthroplasty.

Objective: To discuss the therapeutic effect of distal fixed modular femoral prosthesis for the hip prosthesis revision., Methods: Between August 2004 and May 2008, cementless modular femoral prosthesis was used for hip prosthesis revision in 21 cases. There were 9 males and 12 females, aged from 49 to 72 years (mean, 64.6 years). The time from revision to total hip arthroplasty was 2 to 18 years (mean, 11.7 years). The causes of revision included aseptic loosening in 19 cases (5 cases were periprosthetic femoral fracture), and deep infection in 2 cases. First revision was given in all patients. Preoperative Harris score was 41.8 +/- 3.5; pain visual analogue score (VAS) was 7.62 +/- 0.86., Results: All patients achieved healing of incision by first intention, and no deep venous thrombosis and nerve injury occurred. Twenty-one cases were followed up 2 to 6 years with an average of 4.3 years. No prosthetic loosening or infection occurred. Bone ingrowth was observed around the implant during the follow-up period. At last follow-up, 2 cases had femoral stem subsidence without obvious hip pain and other symptoms, and no special treatment was given. Harris score was 82.7 +/- 3.3 and VAS score was 0.19 +/- 0.51 at last follow-up, showing significant differences when compared with those before operation (P < 0.05)., Conclusion: The short-term result of modular femoral prosthesis is satisfactory in hip prosthesis revision, and it can improve the hip function and relieve the pain greatly.

Objective: To investigate the surgical techniques and clinical outcomes of total hip replacement for patients with end-stage osteoarthritis secondary to developmental dysplasia of the hip., Methods: From May 2004 to March 2008, a total of 36 total hip replacements were performed in 32 patients with end-stage osteoarthritis secondary to developmental dysplasia of the hip. The acetabulum cup was reconstructed in the corresponding anatomical position in all cases. Cemented components were used in 16 hips, and cementless components in the other 20 hips. The mean follow-up was 31.3 months. Clinical outcomes were determined with Harris hip score. Radiographs were taken after the surgery and in every follow-up examination for further reference., Results: All patients postoperatively gained a limb lengthening with an average of (3.4+/-1.3) cm. Three patients had complications, 2 had nondisplaced fractures of the proximal part of the femur,and 1 sciatic nerve palsy which disappeared after 3 months. There was no infection, dislocation and symptomatic deep vein thrombosis. Compared with preoperation, the mean Harris hip scores on the 3rd day, the 14th day after the operation and at the last follow-up were all improved significantly (all P<0.05). There was no loosening, migration, heterotopic ossification radiographically, and no revision during the follow-up., Conclusion: Total hip replacement is an effective treatment for patients with end-stage osteoarthritis secondary to developmental dysplasia of the hip. The key is to place the acetabulum cup in the corresponding anatomical position, and choose proper prosthesises during the surgery.

Objective: To measure the anatomic data of the proximal femur and to design an internal fixation instrument aiming at subtrochanteric fracture., Methods: We measured the anatomic data of 56 pairs of the matching proximal femur specimens: the diameter of femoral head (HD), the axis length of femoral head (HAL), 135 degree femoral head-neck axis length (HNAL), 135 degree femoral head-neck axis upper length (HNAUL), 135 degree femoral head-neck axis underside length (HNADL), the anterior-posterior axis diameter of femoral neck (NAPD), the upper-underside diameter of femoral neck (NUUD), femoral neck-shaft angle (NFA), femoral shaft lateral cortex-greater trochanter angle (SLGA), the medial-lateral diameter of lesser trochanter level's femoral shaft (LSMLD), the anterior-posterior diameter of lesser trochanter level's femoral shaft (LSAPD), the medial-lateral diameter of 5 cm below lesser trochanter femoral shaft (5 cm MLD), and the anterior-posterior diameter of 5 cm below lesser trochanter femoral shaft (5 cm APD). Part of the data was analyzed and compared., Results: HD was (46.69+/-3.73) mm, HAL was (39.22+/-4.17) mm, HNAL was (95.45+/-8.16) mm, HNAUL was (84.02+/-7.11) mm, HNADL was (99.95+/-9.34) mm, NAPD was (26.27+/-3.15) mm, NUUD was (32.24+/-3.31) mm, NFA was 126.21 degree+/-7.13 degree, SLGA was 16.38 degree+/-4.04 degree, LSMLD was (31.05+/-3.57) mm, LSAPD was (27.63+/-2.96) mm, 5 cm MLD was (26.36+/-3.22) mm, and 5 cm APD was (25.59+/-2.75) mm. NFA was positively correlated with SLGA (r=0.396, P=0.003)., Conclusion: It is necessary to design internal fixator to fit the anatomical feature of Chinese femur for the treatment of subtrochanteric fracture, and we should thoroughly consider the angle of the SLGA.

Objective: To evaluate the curative effect of the total hip arthroplasty on the adult patient with osphyarthrosis due to hip infection sequela., Methods: Fifteen patients (7 males, 8 females; age, 36-56 years) with osphyarthrosis due to hip infection sequela underwent the total hip arthroplasty from May 2000 to March 2005. The patients were aged 8-15 years, averaged 11.3 years, when they began to suffer from osphyarthrosis. Their infection was interrupted for 23-44 years (average, 29.5 years) after they were given the total hip arthroplasty. Before operation, all the patients had anchylosis at the different degrees and the total activity range of the hip joint was 30-110 degrees. Among the 15 patients, 4 had the limb-length discrepancy of 2-6 cm (average, 3.8 cm) and 2 had a severe scar after the sinus was closed. All the patients received the total hip arthroplasty performed by the senior surgeons. The small straight stem and the congenital dysplasia of the hip prosthesis were used in 13 patients, the other 2 were given the ordinary prosthesis combined the structural bone grafting. Two fixation patterns were respectively used in the cementless group (4 patients) and the cement group (11 patients). The patients in the cementless group began to do the partially-loading exercise at 3-4 weeks after operation; the patients in the cement group, 2 weeks after operation. The 2 patients with the structural bone allografting began to do the partially-loading exercise 12 weeks after operation., Results: The germiculture and the pathological examination had a negative result in the tissues removed during operation. In the 4 patients with the shortened limbs, the limb-length discrepancy was less than 1.3 cm. The follow-up for 49 months on average (range, 16 -72 months) showed that the Harris score increased from 46 points on average preoperatively to 90.5 points on average postoperatively. None of the patients had recurrent infection or injuries in the nerves and the blood vessels in the hip or aseptic loosening of the prosthesis., Conclusion: The total hip arthroplasty in an adult patient with osphyarthrosis due to hip infection can achieve a satisfactory curative effect in the early stage. The patient's pain can be effectively relieved, and the problems of the poor motion degree of the hip joint and the limb-length discrepancy can be effectively solved. Using the small acetabular prosthesis and the structural bone grafting can sufficiently reconstruct the anatomic acetabulum. If necessary, the small straight stem and the congenital dysplasia of the hip prosthesis can be used in the patient with severe deformity of the proximal femur.

Objective: To study the effect of simultaneous bilateral total hip arthroplasty in a single procedure., Methods: From October 1999 to March 2004, 15 patients (30 hips) underwent simultaneous sequential bilateral total hip arthroplasty (THAs) in a single procedure. Of the 15 patients, 11 were male (22 hips) and 4 were female (8 hips). Their ages ranged from 35 to 70 years. Their courses of disease ranged from 1 year to 50 years (4.8 years on average). The Harris scores of the joint function before the operation ranged from 12 to 45 points (27 points on average). Five were done with Smith-Peterson and 10 were done with Moore., Results: The operative time was 3 hours and 25 minutes to 5 hours (4 hours and 10 minutes on average). The volume of blood transfusion during operation was 400 to 2 400 ml (1160 ml on average). All the 15 patients were followed up for 3 to 35 months (18 months on average). The Harris scores of the joint function after the operation ranged from 70 to 100 points (86 points on average). There was significant difference in the scores between before and after operations (P<0.05). There was only 1 death within 1 months of the operation and no serious between complications such as infection, pulmonary embolism, and deep vein plug. All the patients were still ambulant in the community and gained significant pain relief., Conclusion: Simultaneous bilateral total hip arthroplasty in a single procedure is a safe and effective method. However, the decision of performing single-stage bilateral total hip arthroplasty should be carefully made and preoperative preparation should be sufficiently made.

Lateral field excited (LFE) AT-cut quartz acoustic wave sensors in which the electrodes are located on the reference surface have been fabricated and tested in liquid environments. The sensing surface, which is opposite to the reference surface, is free allowing the electric field of the thickness shear mode (TSM) to penetrate into the liquid. This results in increased sensitivity to both mechanical and electrical property changes of the liquid. In the present paper, several 5-MHz LFE sensors with a range of electrode spacings were exposed to liquid environments in which the viscosity, relative permittivity, and conductivity were varied. The LFE sensors demonstrate sensitivity to viscosity that is more than twice that obtained for the standard quartz crystal microbalance (QCM), and sensitivity to relative permittivity and conductivity about 1.5 times that of the QCM sensors with modified electrodes. The present results clearly indicate that the LFE sensors may have a wide range of liquid phase applications in which sensitivity is crucial.