Post-Marketing Surveillance of Qishe Pill () Use for Management of Neck Pain in a Chinese Patient Cohort to Determine its Safety, Tolerability and Effectiveness / 中国结合医学杂志

OBJECTIVE@#To evaluate the safety and effectiveness of Qishe Pill () on neck pain in real-world clinical practice.@*METHODS@#A multi-center, prospective, observational surveillance in 8 hospitals across Shanghai was conducted. During patients receiving 4-week Qishe Pill medication, Visual Analogue Scale (VAS) and Neck Disability Index (NDI) assessments have been used to assess their pain and function, while safety monitoring have been observed after 2 and 4 weeks.@*RESULTS@#Results from 2,023 patients (mean age 54.5 years) suggest that the drug exposure per unit of body mass was estimated at 3.41 ± 0.62 g/kg. About 8.5% (172/2,023) of all participants experienced adverse events (AEs), while 3.8% (78/2,023) of all participants experienced adverse reaction. The most common AEs were gastrointestinal events and respiratory events. The VAS score (pain) and NDI score (function) significantly decreased after 4-week treatment. An effect-quantitative analysis was also conducted to show that the normal clinical dosage may be consider as 3-4 g/kg, at which dosage the satisfactory pain-relief effect may achieve by 40-mm reduction in VAS.@*CONCLUSION@#These findings showed that patients with cervical radiculopathy who received Qishe Pill experienced significant improvement on pain and function. (Registration No. NCT01875562).

Comparison of surgical effects between extension and flexion type of distal radius fracture / 中国骨伤

OBJECTIVE@#To compare therapeutic effects of internal fixation with volar locking plate in treating extension and flexion type of distal radius fracture (DRF).@*METHODS@#From January 2015 to June 2018, 103 patients with DRF were retrospectively analyzed. According to original fracture displacement direction, patients were divided into extension fracture(Colles) group and flexion fracture (Smith) group. In Colles fracture group, there were 24 males and 44 females aged from 20 to 79 years old with an average of (59.0±13.4) years old;according to AO classification, 9 patients of type A2, 13 patients of type A3, 16 patientsof type C1, 17 patients of type C2 and 13 patients of type C3;the time from injury to operation ranged from 2 to 9 days with an average of (3.9±0.8) days. In Smith fracture group, there were 15 males and 20 females, aged from 27 to 87 years old with an average of (60.1±15.3) years old;according to AO classification, 4 patienst of A2, 7 patients of A3, 14 patients of C1, 5 patients of C2 and 5 patients of C3;the time from injury to operation ranged from 2 to 6 days with an average of (4.1±0.9) days. Operation time, fracture healing time and postoperative complications were recorded between two groups. Disabilities of arm, shoulder and hand (DASH) score at 6 and 8 weeks, 6 and 8 months were used to evaluate functional recovery of affected limbs during each follow up. Volar tilt, radial inclination and radius height were measured at 8 months after operation. Mayo score was measured at 8 months after operation to evaluate recovery of limb function.@*RESULTS@#All patients were followed up for 8 to 30 months with an average of (14.8±4.3) months, and no difference in follow up between two groups (@*CONCLUSION@#Patients with Colles fracture and Smith fracture could receive good reduction and fixation through volar locking plate. The radiographic parameters of both groups recovered satisfactorily after operation. Recovery of volar tilt of Smith fracture group is better than that of Colles fracture group, and early recovery function of Colles fracture group is better than that of Smith group, but there is no significant difference in long-term wrist joint function and incidence of postoperative complications between two groups.

The therapeutic effects of total hip arthroplasty with combined anteversion angle of femoral neck-acetabu lam in Crowe Ⅳ developmental dysplasia of the hip / 实用医学杂志

Objective To evaluate the clinical efficacy of combined anteversion angle of femoral neck-acetabulam in Crowe Ⅳ developmental dysplasia of the hip (DDH) with Wagner Cone total hip arthroplasty. Methods From June 2013 to February 2016,45 cases of CroweⅣDDH were treated with no femoral shortening osteotomy in THA ,including 25 females and 20 males. The outcomes of anteversion angle of femoral neck and acetabulam were measured in CT scan of hip jiont. The outcomes of abduction angle ,hip center were measured radiologically in X-ray of pelvis. Postoperative function was scored by Harris scoring system. Results The mean follow-up time of the 45 patients was(3.2 ± 0.8)years. Using loosening or revision as the end point ,the survival rate was 100%. The outcomes of preoperative anteversion angle of acetabulam,femoral neck,acetabulam-femoral neck was(27.70 ± 5.35)°,(47.76 ± 7.25)°,and(74.90 ± 8.43)° in CroweⅣgroup,and those of postoperative anteversion angle was(19.82 ± 2.41)° ,(23.35 ± 3.84)° and(44.90 ± 5.18)° ,respectively. There was significant difference between the two groups(P < 0.05). The average height of preoperative dislocation in femoral head was (5.8 ± 1.2)cm and the postoperative average displacement of femoral lesser trochanter was (3.6 ± 0.8)cm. The Harris hip score was improved from preoperative(46.66 ± 7.28)to(90.36 ± 4.72). For most patients,hip pain were significantly relieved ,range of motion of the hip was improved ,and the gait returned to normal. Femoral nerve injury occurred in 2 cases and the case recovered after 3 months respectively. Conclusions The deformity of hip and the stability and matching degree of the prosthesis was evaluated with the combined anteversion angle of femoral neck-acetabulam in CroweⅣDDH. The Wagner Cone can effectively maintain the stability of the hip joint in the non-amputated total hip replacement.

Influences of osteoporosis on relationship between trabecular stress and microdamage / 医用生物力学

Objective To quantify the stress and strain of trabecular bone with microdamage/microfracture by using micro-CT and micro-finite element (μFE) analysis, so as to investigate the effects of osteoporosis on relationship between trabecular stress and microdamage/microfracture. Methods Two cylindrical specimens of healthy and osteoporotic acetabular trabecular bones were scanned by micro-CT to build 3D μFE analysis models. The uniaxial compression on two specimens was simulated under frictionless displacement boundary condition. The trabecular stress, trabecular strain, microdamage and microfracture under different apparent strains were calculated through nonlinear μFE analysis. Results For both the healthy and osteoporotic trabeculae under apparent strain of 0.05%-0.50%, the undamaged trabecular stress was under 50 MPa, while the damaged trabecular stress was above 110 MPa. Compared with the osteoporotic trabeculae, the mean stress of the healthy trabeculae was relatively higher, but the maximum stress of the osteoporotic trabeculae was higher. Trabecular damage occurred in both the healthy and osteoporotic trabeculae, while the healthy trabeculae showed more microdamage, and microfracture occurred in the osteoporotic trabeculae. Conclusions Within the scope of apparent strain, the healthy trabeculae can withstand a higher stress with more trabecular microdamage, and microfractures might occur in the osteoporotic trabeculae under the high stress.

Dynamic Alterations in Microarchitecture, Mineralization and Mechanical Property of Subchondral Bone in Rat Medial Meniscal Tear Model of Osteoarthritis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The properties of subchondral bone influence the integrity of articular cartilage in the pathogenesis of osteoarthritis (OA). However, the characteristics of subchondral bone alterations remain unresolved. The present study aimed to observe the dynamic alterations in the microarchitecture, mineralization, and mechanical properties of subchondral bone during the progression of OA.</p><p><b>METHODS</b>A medial meniscal tear (MMT) operation was performed in 128 adult Sprague Dawley rats to induce OA. At 2, 4, 8, and 12 weeks following the MMT operation, cartilage degeneration was evaluated using toluidine blue O staining, whereas changes in the microarchitecture indices and tissue mineral density (TMD), mineral-to-collagen ratio, and intrinsic mechanical properties of subchondral bone plates (BPs) and trabecular bones (Tbs) were measured using micro-computed tomography scanning, confocal Raman microspectroscopy and nanoindentation testing, respectively.</p><p><b>RESULTS</b>Cartilage degeneration occurred and worsened progressively from 2 to 12 weeks after OA induction. Microarchitecture analysis revealed that the subchondral bone shifted from bone resorption early (reduced trabecular BV/TV, trabecular number, connectivity density and trabecular thickness [Tb.Th], and increased trabecular spacing (Tb.Sp) at 2 and 4 weeks) to bone accretion late (increased BV/TV, Tb.Th and thickness of subchondral bone plate, and reduced Tb.Sp at 8 and 12 weeks). The TMD of both the BP and Tb displayed no significant changes at 2 and 4 weeks but decreased at 8 and 12 weeks. The mineral-to-collagen ratio showed a significant decrease from 4 weeks for the Tb and from 8 weeks for the BP after OA induction. Both the elastic modulus and hardness of the Tb showed a significant decrease from 4 weeks after OA induction. The BP showed a significant decrease in its elastic modulus from 8 weeks and its hardness from 4 weeks.</p><p><b>CONCLUSION</b>The microarchitecture, mineralization and mechanical properties of subchondral bone changed in a time-dependent manner as OA progressed.</p>

Resurfacing arthroplasty for hip dysplasia:evaluation of treatment outcome / 中华骨科杂志

Objective To assess the functional restoration in patients with developmental dysplasia of the hip (DDH) who underwent hip resurfacing arthroplasty and to determine whether greater abduction angle of the acetabular component is relat?ed to larger diameter of femoral head component. Methods We reviewed 34 DDH cases (9 hips of 8 males and 25 hips of 24 fe?males, mean age 44.6±11.85 years at the time of surgery) on whom we performed hip resurfacing arthroplasty (HRA) from October 2006 to September 2009. The total hip Arthroplasty (THA) group was consisted of 35 DDH cases (8 hips of 8 males and 27 hips of 25 females, mean age 43.7±10.4 years at the time of surgery). All operations were performed by the same doctor over the same peri?od. Assessment of the functional hip scores was conducted by Harris Hip Scores. A radiographic study was also performed to evalu?ate the implants stability and abduction angle of the acetabular components. All the data was analyzed with Kolmogorov?Smirnov method. Results The mean follow?up was 6.2 years in the HRA group. The Harris Hip Score improved from 54.9±13.2 to 97.3± 6.2 after the surgery. The mean abduction angle of the acetabular component was 51.6° ± 5.33°, hip flexion was 127° ± 6.9° and mean diameter of femoral head was 46.5±1.5 mm. The mean follow?up was 5.9 years in the THA group. The Harris Hip Score im?proved from 51.6±19.7 to 95.6±7.9 after the surgery. The mean abduction angle of the acetabular component was 43.9°±4.90°, hip flexion was 117°±4.2°. There was no failure of the prosthesis, peri?prosthetic fracture and infection in either group. There was sig?nificant difference in the abduction angle of the acetabular component (P<0.05) and flexion of the hip between the two groups (P<0.05). Conclusion Patients in the HRA group had a better functional restoration and larger range of motion. Furthermore, a larger diameter of femoral head component could be achieved by placing the acetabular component in a greater abduction angle, which may contribute to a better long?term stability.

Total hip arthroplasty with no femoral shortening osteotomy for unilateral Crowe Ⅳ developmental dysplasia of the hip / 中华骨科杂志

Objective To evaluate the clinical efficacy of total hip arthroplasty (THA) with no femoral shortening oste?otomy for unilateral CroweⅣ developmental dysplasia of hip. Methods From October 2007 to January 2010, 32 patients with CroweⅣdevelopmental dysplasia of hip in one side underwent THA, including 20 females and 12 males, with an average age of 49.4 ± 9.7 years (range, 23-60 years). There were 15 cases as normal and 17 as mild developmental dysplasia of hip in the other side. The THA were performed with requisite soft tissue release and direct leverage using an elevator but with no femoral shorten?ing osteotomy. The patients' satisfaction, Harris hip score, bilateral leg?length discrepancy and pelvic obliquity was used to assess the clinical results. Results All of patient were followed up for 1-6 years, average 4.0 ± 1.5 years. No loosening or failure of component occurred by the end of follow?up. The Harris hip score was improved from preoperative 36.5±10.3 (20-63) to 89.8± 4.9 (80-97), and the excellent and good rate was 100% (excellent 16 cases, good 16 cases). The satisfactory rate was 93.8%(30/32). The leg?length discrepancy of the bilateral sides and the pelvic obliquity was corrected gradually and the gait returns to normal. Nine cases have valgus knee after THA and 4 cases of them felt uncomfortable after long?distance walk. Femoral nerve injury occurred in 2 cases. All of cases recovered after 1 and 3 months respectively. No infection and dislocation oc?curred. Conclusion THA with no femoral shortening osteotomy can achieve good clinical results in patients with unilateral CroweⅣdevelopmental dysplasia of hip. The discrepancy of leg?length will be diminished with the correction for pelvic obliquity.

Cyclic stretch-induced apoptosis in human osteoarthritic chondrocytes is mediated by reactive oxygen species generation / 医用生物力学

Objective To explore the mechanism of reactive oxygen species (ROS) generation on apoptosis of human osteoarthritic chondrocytes induced by cyclic stretch in vitro. Methods The human osteoarthritic chondrocytes were subjected to cyclic stretch at the frequency of 0.5 Hz with 20% elongation. The chondrocytes without cyclic stretch were used as a control. ROS generation in chondrocytes was inhibited by the antioxidant, N-acetyl-L-cysteine (NAC) and potentiated by the glutathione depleter, DL-buthionine-［S,R］-sulfoximine (BSO). Apoptosis was detected by flow cytometry. Intracellular ROS was detected using DCFH-DA and caspase-9 activity was measured using spectrophotometry. Results The cyclic stretch at the frequency of 0.5 Hz with 20% elongation induced ROS generation, and activation of caspase-9 and apoptosis in human osteoarthritic chondrocytes were significantly increased (P<0.05). The inhibition or potentiation of intracellular ROS by NAC or BSO could obviously inhibit or improve caspase-9 activity and apoptosis in chondrocytes under cyclic stretch (P<0.05). Conclusions Cyclic stretch-induced apoptosis in human osteoarthritic chondrocytes is mediated by ROS generation and activation of caspase-9. Suppression of ROS can prevent chondrocytes from apoptosis induced by cyclic stretch.

Correlation between the incidence of hip fractures and the proximal femur by 3D geometric anatomy / 医用生物力学

Objective To measure the hip anatomic parameters and explore the differences between the hip fracture group and the normal group, analyze their effect on the incidence of hip fractures and fracture types by using computer aided design (CAD) and three-dimensional reconstruction technique. Methods Through CT scan images from the lower-extremity of hip fracture patient, the 3D anatomic model was established by Mimics10.01 software, and the 3D anatomic parameters of the normal proximal femur, namely femoral neck anteversion angle (FNAA), neck-shaft angle (NSA), femoral head diameter (FHD), length of femoral neck axis (LFNA) in the lower-extremity were measured. Results The averages of FNAA, NSA, FHD, LFNA in femoral neck fracture group were (7.9±4.6)°, (128.6±4.6)°, (46.0±4.6) mm, (47.1±5.1) mm, and those parameters in intertrochanteric fracture group were (15.5±6.8)°, (134.7±6.9)°, (45.3±3.6) mm, (46.7±3.4) mm. The FNAA and NSA in intertrochanteric fracture group were significantly larger than those in femoral neck fracture group regardless of gender (P<0.01). The FNAA and NSA in both fracture groups showed significant differences as compared with the normal group. ConclusionsThe risk of femoral intertrochanteric fracture will increase when the FNAA is larger than the normal range in Chinese, while the risk of femoral neck fracture will increase when the FNAA is smaller than the normal range in Chinese. The NSA of hip fracture patients was larger as compared with normal Chinese. The larger NSA will lead to a higher risk of femoral intertrochanteric fracture. There exist some differences in anatomic parameters of the proximal femur between the fracture group and the normal group, especially in the angle parameter. The femoral intertrochanteric fractures are more prone to occur in the older people, while the femoral neck fractures are more prone to occur in the younger people.

Mechanical strength of biological canulated cancellous screw / 医用生物力学

Objective To develop a biological canulated screw and evaluate its mechanical properties, so as to provide theoretical basis for the bio therapy of fracture with enrichment technique of bone marrow stem cells, which could be diffused through the canula, particularly for promoting bone union of femoral neck fracture and preventing avascular necrosis of femoral head. Methods TC4 titanium alloyed canulated cancellous screw (7.3 mm in diameter) commonly used for internal fixation of femoral neck fracture was improved by designing an end sealing plug and side holes in a 900 mm-long canulated screw. The side holes were arranged along the axis of screw, and the first side hole was 20 mm away from the screw tip. The distance between each side hole was 10 mm, and the number of side holes ranged from 0 to 6. The screws without holes were tested as control, and the rest were divided into two groups, i.e., group A: force direction parallel to the side hole, group B: force direction perpendicular to the side hole. Three point bending test on the screw was conducted by using Instron material testing machine, so as to study the relationship between the mechanical strength of the screw and the number of side holes, and the loading direction. Results (1) When the force direction was parallel to the side hole, which was confined within 0, 1 or 2, the bending deformation of the screw reached 3 mm, and no differences were found in the maximum loads and elastic modulus of the screw. However, when the number of side holes was increased to 3 or more, a significant reduction in the maximum load and elastic modulus of the screw was found (P＜0.05). (2) When the force direction was perpendicular to the side hole, which was confined within 0,1 or 2, and the bending deformation of the screw reached 3 mm, no significant differences were found in the maximum loads of the screw. While no significant difference was found in the elastic modulus of the screw when the side hole was 0, 1, 2 and 3. With an increase in the number of side holes, the maximum loads (≧ 3 side holes) and elastic modulus (≧ 4 side holes) were significantly reduced (P＜0.05). (3) When the force direction was perpendicular to the side hole and the number of side holes was 3 or more, the maximum loads and elastic modulus of the screw were all significantly higher than the screw with the same number of side hole under force direction parallel to the side hole. Conclusions (1) For achieving better mechanical properties of the screw, the number of side holes in titanium alloyed canulated cancellous screw (7.3 mm in diameter) should be within 2; (2) If the number of side holes was equal or over 3, screws under force direction perpendicular to the side hole could provide better mechanical properties than screws under force direction parallel to the side hole. This study may provide some theoretical evidence and support for future clinical development and practice of the biological canulated screw.

Wear analysis and diagnostic reasoning on clinical failure of artificial hip joints / 医用生物力学

Objective To investigate the wear mechanism of artificial hip joints and the criteria for wear life definition, analyze the causes of abnormal wear and the clinical manifestations of wear failure, establish the reasoning route of failure incidents. Methods The wear process and early factors on abnormal wear in artificial hip joints were studied through elastohydrodynamic lubrication computation and finite element analysis; the service life of artificial hip joints was determined through establishing criteria for wear life definition; the clinical manifestations of wear failure were introduced and classified through wear-osteolysis morphological matrix; the reasoning logic of failure incidents was established through clinical investigation. Results The minimal synovium thickness and contact stress between the femoral head and the acetabular cup were calculated, and the effect of relevant parameters was studied as theoretical references for wear analysis; the criteria on wear life definition of artificial hip joints were proposed, namely the mechanistic failure due to geometric change in artificial hip joints and the biological failure due to osteolysis; nine kinds of clinical manifestation for wear failure were found; the reasoning route for failure incidents was presented. Conclusions Primary wear process in artificial hip joints includes boundary and mixed friction, adhesive, ploughing and third-body wear; surface quality, fit clearance between the acetabular cup and the femoral head, and roundness have great impact on early abnormal wear; normal mechanistic life of metal-UHMWPE artificial hip joint can reach 40 years, but its maximum biological life is no more than 10-15 years, which is the constraint of prosthesis life today; the diversity of clinical manifestations for wear failure is the morphological Results of mechanical wear and osteolysis, which is helpful for the reasoning route of failure incidents.

Effect from simvastatin on osteogenesis of the lumbar vertebra in aging rats / 医用生物力学

Objective To evaluate the role of simvastatin in preventing and curing osteoporosis vertebrae by examining the effect from simvastatin on osteogenesis of the lumbar vertebrae in aging rats. Methods Sixty 15-month-old male SD rats were divided into six groups: the control group (injected with normal saline for three month), the baseline group (executed upon the gastric irrigation), the simavastatin-treated group (gastric irrigation with simavastatin at the dose of 5, 10, 20 and 40 mg/kg/d, respectively, for three month). L4 vertebrae were checked by Dual-Energy X-ray Absorptionmetry (DXA), Peri-quantiy CT (pQCT) and mineral apposition rates test. L5 vertebrae were checked by mechanical compression test. Results The value of DXA, pQCT and mineral apposition rate of 10 mg simvastatin group were slightly higher than that of the control group, but no significant differences were found between the two groups. The bone material properties of 10 mg and 20 mg simvastatin group were better than those of the control group, with no significant differences. Conclusions Although 10 mg simvastatin group (equivalent to 12~24 mg/d for human) seemed to have better properties than the other simvastatin groups, but there were no significant differences among these simvastatin-treated group. It is indicated that simvastatin doesn't play a positive role in promoting osteogenesis of the lumbar vertebrae in aging rats, so it may have no preventing or curative effect for osteoporosis of the lumbar vertebrae.

Biomechanical analysis and reasoning on aseptic loosening failure after total hip arthroplasty / 医用生物力学

Objective To propose some detailed methods for diagnosis of aseptic loosening failure in clinic by studying the mechanical mechanism and the specific causes of aseptic loosening failure after the total hip arthroplasty (THA). Methods The causes of aseptic loosening were investigated from the view of biomechanics, such as strength of the bone cement layer, interface fretting, stress shielding, wear and osteolysis; the relationships between aseptic loosening failure and products, clinical and patient factors were analyzed; the method to detect loosening before the revision surgery was also studied. Results The reasoning route for aseptic loosening failure analysis after THA was proposed, and detection of aseptic loosening with fluoroscopic analysis (FSA) technique before the revision surgery was conducted successfully. Conclusions The reasoning route for aseptic loosening failure analysis can help to discover reasons of failure occurrence. Loosening can be detected and confirmed in vivo by FSA method, which can also assist the clinician for diagnosis and treatment of aseptic loosening after the THA.

Effects of sex and lower extremity alignment on orientation of the knee joint line in knee surgery / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Determination of the proper orientation of the knee articular surface is required both for correction of knee malalignment by osteotomy and for correct component alignment in knee arthroplasty. We sought to determine whether the patients' sex and lower extremity alignment (hip-knee-ankle angle) affects proper knee realignment in osteotomy or component alignment in total knee arthroplasty.</p><p><b>METHODS</b>We examined 199 healthy adult knees with malalignment of < 5° to determine the mechanical medial distal femoral angle, mechanical medial proximal tibial angle, surgical transepicondylar axis angle, and discrepancies between bone-cut orientations of osteotomy or total knee arthroplasty and the joint line of the distal femoral condyles, posterior femoral condyles and proximal tibial plateaus, using a three-dimensional computed tomography model.</p><p><b>RESULTS</b>The mean mechanical medial distal femoral angle and mean mechanical medial proximal tibial angle were (94.4 ± 1.9)° and (87.6 ± 1.8)° respectively for women and (93.8 ± 2.0)° and (87.1 ± 1.4)° respectively for men. The surgical transepicondylar axis angle was (2.9 ± 1.6)° for women and (3.2 ± 1.7)° for men. Independent of sex, the hip-knee-ankle angle was closely related to the mechanical medial distal femoral angle and mechanical medial proximal tibial angle, but not to the surgical transepicondylar axis angle. A slightly more valgus alignment of the knee and a more valgus angulation of the distal femoral joint line were found in women, whereas a more varus angulation of the proximal tibial joint line was found in men. Sex had the greatest effect on knee joint line orientation when the lower extremity was valgus in alignment.</p><p><b>CONCLUSIONS</b>A more valgus femoral joint line can be expected in women and in persons with valgus lower extremity alignment; a more varus tibial joint line can be found in men and in persons with varus lower extremity alignment.</p>

Role of mechanobiology in mesenchymal stem cell-based tissue engineered cartilage / 医用生物力学

Mesenchymal stem cells (MSCs) is an ideal cell type extensively used in cartilage multipotency to differentiate into cartilage and can be isolated from a wide variety of tissue sources with strong in vitro expansion. Since cartilage has the important mechanical properties, it is necessary to highlight and evaluate the mechanobiological properties of MSC-based tissue engineered cartilage. To better understand the relationship between inducing factor of cartilage repair, signal pathway and mechanical properties, this paper reviews the advances made on research of mechanobiology in MSC-based tissue engineering cartilage, discusses the existing problems in this field, and try to point out some new approaches or directions worthy of such investigation.

Effect of impaction on gene-modified cells seeded on granular bone allografts in vitro and in vivo / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>While attempting to restore bone stock, impaction bone grafting employed during revision joint surgery may result in slow and limited allograft incorporation into host bone. A new approach including gene-modified bone marrow stromal cells (BMSCs) in combination with impaction bone grafting may effectively restore bone stock and improve allograft incorporation. This study aimed to investigate the effect of impaction on gene-modified BMSCs seeded on granular bone allografts in vitro and in vivo.</p><p><b>METHODS</b>Deep-frozen, granular, cancellous bone allografts from canines were prepared to serve as cell delivery scaffolds and were seeded with green fluorescent protein (GFP) genetically-modified BMSCs to construct cell-allograft composites. The composites were impacted in a simulative, in vitro impaction model and cultured for further analysis under standard conditions. Four Beagle dogs, treated with bilateral, uncemented proximal tibial joint hemiarthroplasty with a prosthesis, were implanted with autologous GFP gene-modified cell-allograft composites to repair the bone cavity around each prosthesis.</p><p><b>RESULTS</b>A significant reduction in cell viability was observed after impaction by fluorescence microscopy in vitro. However, there remained a proportion of GFP-positive cells that were viable and functionally active, as evidenced by the secretion of GFP protein in vitro and in vivo.</p><p><b>CONCLUSIONS</b>Gene-modified BMSCs seeded on granular allografts were able to withstand the impaction forces and to maintain their normal functions in vitro and in vivo, in spite of a partial loss in cell viability.</p>

Evaluation of damage to trabecular bone of the osteoporotic human acetabulum at small strains using nonlinear micro-finite element analyses / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>With advance of age, alterations in bone quality, quantity and microarchitecture render osteoporotic trabecular bone become more sensitive to local failure. The aims of the present study were to clarify the extent to which the distribution of tissue-level stresses and strains was affected by structural changes and the extent to which osteoporotic acetabular trabecular bone was damaged at small strains.</p><p><b>METHODS</b>Using a DAWING 4000A supercomputer, nonlinear micro-finite element (microFE) analyses were performed to calculate the tissue-level strains and stresses for each element in the trabecular bone of one osteoporotic acetabulum at small strains to quantify the tissue-level damage accumulation and mechanical properties.</p><p><b>RESULTS</b>In contour plots of the tissue, maximum principal logarithmic strains, high tissue-level strains, both compressive and tensile, were observed in the osteoporotic trabecular bone at small apparent strains from 0.2% to 0.5% strain. The compressive apparent stress-strain curve showed typical nonlinear behavior and tangent modulus reduction with increasing strains. The microdamage curve suggested that microdamage began at 0.2% apparent strain in the osteoporotic trabecular bone and increased sharply, although very few microfractures occurred. The quartiles of the maximum principal logarithmic strains, minimum principal logarithmic strains and Von Mises stresses increased nonlinearly. For the inter-quartile range of the Von Mises stresses, a leap occurred at small strains ranging from 0.2% to 0.3% while microdamage commenced.</p><p><b>CONCLUSIONS</b>Extensive microdamage was primarily responsible for the large loss in apparent mechanical properties that occurred in the trabecular bone of the osteoporotic acetabulum at small strains. With increasing apparent strains, continuous nonlinear increments of tissue-level strains and stresses resulted in microdamage that propagated throughout the specimen with very few microfractures.</p>

Clinical study of lumbar fusion by hybrid construct of stem cells technique and biodegradable material / 中华外科杂志

<p><b>OBJECTIVE</b>To explorer the effectiveness of enriched bone marrow stem cells technique for lumbar fusion.</p><p><b>METHODS</b>With the randomization and control principles, 2 graft materials [Enrichment bone marrow mesenchymal stem cells hybridized with beta-tri calcium phosphate (composite graft group), autologous iliac crest bone graft (autograft group)] were compared in posterior lumbar fusion procedures. 56 patients with degenerative disc disease, lumbar instability or spinal stenosis, were included. The volume of cells suspension in pre- and post-enrichment and the number of nucleated cells (NCs) were identified. The number of osteoprogenitor cells was estimated by counting the colony-forming units which express alkaline phosphatase (CFUs/ALP+). Then the efficiency of the enrichment was evaluated. Clinical follow-up with roentgenogram and Oswestry scale scores was performed for outcome evaluation.</p><p><b>RESULTS</b>(249 +/- 31) ml bone marrow per patient from bilateral iliac crests was aspirated peri-operatively. About (43 +/- 11) ml enriched bone marrow was collected. The number of NCs was concentrated from (15.9 +/- 3.3) x 10(6)/ml to (44.1 +/- 10.8) x 10(6)/ml, CFUs/ALP+ was significantly increased from (118 +/- 86)/ml to(486 +/- 305)/ml. The follow-up was about (26.3 +/- 7.5) months. There was no significant differences in age, gender, disease and fusion segments between the two groups. The fusion rate was 93.3% and 96.2% for composite graft group and autograft group, respectively (chi2 = 0.2146, P = 0.6432). There was no difference in operation time between the two group (t = 0.5243, P = 0.6022), but blood loss in composite graft group was more than that in autograft group (t = 6.4664, P < 0.01). Cell salvage for auto-transfusion could transfuse back half of the blood loss during operation. No hematoma or chronic soreness in the bone marrow donor sites of composite graft group occurred, but a little exudation or moderate swelling in the wound happened in 4 cases which disappeared under medical treatment. Meanwhile, 15.4% patients had hematoma in the iliac bone donor site and 26.9% patients had chronic soreness, but no case had wound problem in autograft group. As for Oswestry scale scores, there was no significant difference between the two groups.</p><p><b>CONCLUSIONS</b>The enrichment technique of autologous bone marrow stem cells can greatly increase the concentration of MSCs. It is a rapid and safe method used peri-operatively. The composite material of enriched MSCs and porous beta-TCP is a good bone substitute in posterior spinal fusion.</p>

Cell Specific Non-Viral Vector Enhances Expression of BMP-2 Gene in Human Dermal Fibroblasts / 上海第二医科大学学报

Objective To construct the fibroblast-specific non-viral vector pcDNA3-CEP-BMP-2 containing collagen 1A2 enhancer and promoter,and to validate the enhancement of BMP-2 expression in the human dermal fibroblasts by this vector,compared with the routine non-viral BMP2 vector. Methods The sequences for collagen 1A2 enhancer and promotor,and BMP-2 gene were ligated into the pcDNA3 plasmids.The plasmids were transfected into human skin fibroblasts and vein endothelial cells by means of cationic liposomes.The expressions of the plasmids in these two kinds of cells were detected by RT-PCR.The osteogenic phonotypes of fibroblasts were determined.(Results)pcDNA3-CEP-BMP-2,which contained collagen 1A2 enhancer and promoter could enhance the BMP-2 expression in the fibroblasts but not in vein endothelial cells.Osteogenetic phenotypes were more obvious in the fibroblasts transfected with pcDNA3-CEP-BMP-2 than in pcDNA3-BMP-2-transfected ones. Conclusion Collagen 1A2 enhancer and promoter can enhance BMP2 expression in fibroblasts.

Total hip arthroplasty for Crowe type-IV development dysplasia of hip in adults / 中华外科杂志

<p><b>OBJECTIVE</b>To determine the operation procedure of total hip arthroplasty (THA) for Crowe type-IV developmental dysplasia of hip and its relationship with nerve injury.</p><p><b>METHODS</b>A consecutive series of 39 THAs was performed for Crowe type-IV developmental dysplasia of hip in 35 patients (all female). The mean age of the patients at the time of surgery was 46 years (range 36 - 56 years). Thirty-five hips in 31 patients were followed up. The average follow-up period of the whole series was 4 years (range 1 - 8 years). All procedures were carried out through a lateral-posterior approach. In 33 of 35 hips, the cup was inserted in the "true" acetabulum. All the prostheses used were cementless, except for 5 cemented femoral stems in 5 patients. Each patient was evaluated clinically and by radiographs before the operation and during the follow-up period, according to the Harris hip score (HHS).</p><p><b>RESULTS</b>None of the cups and stems were revised for aseptic loosening, dislocation or infection during the follow-up period. The mean preoperative HHS was 43 compared with the postoperative HHS of 87. The mean amount of postoperative leg lengthening was 5 cm (range 4 - 6 cm).</p><p><b>CONCLUSIONS</b>The reconstruction of the hip at the level of the "true" acetabulum through a lateral-posterior approach is a safe and effective procedure of THA for Crowe type-IV developmental dysplasia of hip in adults. Acute leg lengthening of less than 6 cm could not cause nerve injury.</p>