BACKGROUND Tibial plateau fractures often require structural support for metaphyseal defects created during articular reduction.While autologous bone grafting has been utilized as the gold standard,bone substitutes of...BACKGROUND Tibial plateau fractures often require structural support for metaphyseal defects created during articular reduction.While autologous bone grafting has been utilized as the gold standard,bone substitutes offer advantages including reduced donor site morbidity.Our meta-analysis evaluated the comparative efficacy of these approaches across clinical and operative outcomes.AIM To conduct a systematic review and meta-analysis of randomized controlled trials comparing autologous bone grafts with bone substitutes for tibial plateau fractures.METHODS We conducted a systematic review and meta-analysis of randomized controlled trials comparing autologous bone grafts with bone substitutes for tibial plateau fractures.Primary outcomes included joint depression,secondary collapse rate,operative time,blood loss,and infection rate.Subgroup analyses were performed by fracture complexity,geographic region,and methodological factors.In addition to that,we also developed a combined outcome score integrating structural,procedural,and complication domains.RESULTS Seven randomized controlled trials with 424 patients(296 bone substitute,128 autograft)were included.No significant differences in joint depression or secondary collapse were observed across fracture complexity categories.Geographic variations were evident,with Western studies showing significantly higher risk of secondary collapse with autografts(risk ratio=1.45,P value=0.02).Both Western and Asian studies have demonstrated significantly reduced blood loss with bone substitutes(70-90 mL less),while operative time reduction was more significant in the Asian studies(23.65 vs 8.00 minutes,P value=0.04 for subgroup difference).The combined outcome score(standardized effect size-0.2481)favored bone substitutes,primarily due to procedural advantages.CONCLUSION Bone substitutes provide similar structural outcomes to autologous bone grafts while having better procedural advantages in tibial plateau fracture management.These findings support bone substitutes as a viable option across fracture patterns.Future studies should focus on specific bone substitute formulations and cost-effectiveness analyses.展开更多
Objective: To better characterize nonunion endochondral bone healing and evaluate novel therapeutic approaches for critical size defect healing in clinically challenging bone repair, a segmental defect model of bone i...Objective: To better characterize nonunion endochondral bone healing and evaluate novel therapeutic approaches for critical size defect healing in clinically challenging bone repair, a segmental defect model of bone injury was adapted from the threepoint bending closed fracture technique in the murine femur.Methods: The mouse femur was surgically stabilized with an intramedullary threaded rod with plastic spacers and the defect adjusted to different sizes. Healing of the different defects was analyzed by radiology and histology to 8 weeks postsurgery. To determine whether this model was effective for evaluating the benefits of molecular therapy, BMP-2 was applied to the defect and healing then examined.Results: Intramedullary spacers were effective in maintaining the defect. Callus bone formation was initiated but was arrested at defect sizes of 2.5 mm and above, with no more progress in callus bone development evident to 8 weeks healing. Cartilage development in a critical size defect attenuated very early in healing without bone development, in contrast to the closed femur fracture healing, where callus cartilage was replaced by bone. BMP-2 therapy promoted osteogenesis of the resident cells of the defect, but there was no further callus development to indicate that healing to pre-surgery bone structure was successful.Conclusions: This segmental defect adaptation of the closed femur fracture model of murine bone repair severely impairs callus development and bone healing, reflecting a challenging bone injury. It is adjustable and can be compared to the closed fracture model to ascertain healing deficiencies and the efficacy of therapeutic approaches.展开更多
BACKGROUND Comminuted calcaneal fractures present significant treatment challenges.Open reduction and internal fixation carries risks such as infection and skin necrosis,while minimally invasive techniques may comprom...BACKGROUND Comminuted calcaneal fractures present significant treatment challenges.Open reduction and internal fixation carries risks such as infection and skin necrosis,while minimally invasive techniques may compromise reduction stability.Conservative management is generally limited to minimally displaced fractures.Traditional Chinese manual bone-setting has a long history in fracture treatment and is renowned globally for achieving functional reduction.It offers distinct advantages including lower cost,minimal soft tissue trauma,and the avoidance of expensive reduction equipment or internal fixation materials.CASE SUMMARY A 60-year-old female presented with left foot pain and limited mobility following a fall.Computed tomography scan revealed a Sanders type IV calcaneal fracture with a Böhler angle of 0°.A standardized,stepwise Traditional Chinese manual bone-setting was initially performed,followed by percutaneous screw fixation through several mini-incisions after satisfactory alignment was confirmed under fluoroscopy.The Visual Analog Scale score decreased from 5 on postoperative day 1 to 3 by day 3.The American Orthopaedic Foot and Ankle Society score improved from 73 at 6 weeks to 90 at 3 months,indicating rapid functional recovery and high patient satisfaction.At 7 months postoperatively,the American Orthopaedic Foot and Ankle Society score reached 95,prompting removal of internal fixation.At the 6-year follow-up,reduction remained well maintained,with the Böhler angle preserved at 22°.CONCLUSION The combination of Traditional Chinese manual bone-setting and percutaneous screw fixation achieved satisfactory functional reduction for comminuted calcaneal fractures.展开更多
Long-bone fractures are common complaints in orthopedic surgery.In recent years,significant progress has been made in robot-assisted fracture-reduction techniques.As a key medical device for diverse fracture morpholog...Long-bone fractures are common complaints in orthopedic surgery.In recent years,significant progress has been made in robot-assisted fracture-reduction techniques.As a key medical device for diverse fracture morphologies and sites,the design of the reduction robot has a profound impact on the reduction outcomes.However,existing reduction robots have practical limitations and cannot simultaneously satisfy clinical requirements in terms of workspace,force/torque,and structural stiffness.To overcome these problems,we first analyze the potential placement areas and performance requirements of reduction robots according to clinical application scenarios.Subsequently,a 3UPS/S-3P hybrid configuration with decoupled rotational and translational degrees of freedom(DOFs)is proposed,and a kinematic model is derived to achieve the motion characteristics of the remote center of motion(RCM).Furthermore,the structural design of a hybrid reduction robot with an integrated distal clamp and proximal fixator was completed,and a mechanical prototype was constructed.The results of the performance evaluations and static analysis demonstrate that the proposed reduction robot has acceptable workspace,force,and torque performance and excellent structural stiffness.Two clinical case simulations further demonstrated the clinical feasibility of the robot.Finally,preliminary experiments on bone models demonstrated the potential effectiveness of the proposed reduction robot in lower-limb fracture reduction.展开更多
A monoclonal antibody raised against bone morphogenetic protein (BMP-McAb) has been used to demonstrate the presence of bone morphogenetic protein(BMP) in experimental fracture healing. Rabbit mandibles were fractured...A monoclonal antibody raised against bone morphogenetic protein (BMP-McAb) has been used to demonstrate the presence of bone morphogenetic protein(BMP) in experimental fracture healing. Rabbit mandibles were fractured using standardized methods and left to heal for 3, 7, 14, 21 and 24 d, respectively. The avidin-biotin complex (ABC) method demonstrated an accumulation of positively stained primitive mesenchymal cells at the fracture site in the hematoma stage of bone repair. These cells appeared to undergo differentiation into positively-stained chondroblasts and osteoblasts during the phase of callus formation. Undifferentiated mesenchymal cells showed a high positive reactivity in the early post-fracture stages but a much lower reactivity during the remodelling phase.The results of our study suggest that bone inductive processes are accompanied by the presence of BMP in osteoprogenitor cells during fracture healing of the mandible and that BMP may play a significant role in osteogenesis during bone healing.展开更多
BACKGROUND The National Institute for Health and Care Excellence(NICE)guidelines have advised further research is required into investigating the added prognostic value of bone mineral density(BMD)in the assessment of...BACKGROUND The National Institute for Health and Care Excellence(NICE)guidelines have advised further research is required into investigating the added prognostic value of bone mineral density(BMD)in the assessment of fracture risk with the Fracture Risk Assessment Tool(FRAX)score.AIM To investigate the significance of BMD in fracture neck of femur patients and compare it to the outcome of the FRAX score.METHODS Inclusion criteria for this study were all patients who underwent dual-energy Xray absorptiometry(DXA)scan following fracture neck of femur between 2015 and 2017.Analysis of BMD,FRAX scores and patient demographic data was undertaken.RESULTS A total of 69 patients were included in the study,mean age 74.1 years.There was no significant difference between mean BMD of the femoral neck in males(0.65)as compared to females(0.61)(P=0.364).Analyses showed no significant correlation between BMD and menopause age(rs=-0.28,P=0.090).A significant difference was seen of the femoral neck BMD between the different fracture pattern types(P=0.026).A stronger correlation was observed between BMD of femoral neck and FRAX major score(rs=-0.64,P<0.001)than with BMD of lumbar spine and FRAX major score(rs=-0.37,P=0.003).CONCLUSION This study demonstrated that BMD of the femoral neck measured by DXA scan is of added prognostic value when assessing patients for risk of fracture neck of femur in combination with the FRAX predictive scoring system.展开更多
Bones are organs of the skeletal system, providing shape, mechanical support, and protection to the body and facilitating the movement. In addition, bones contribute to the mineral homeostasis of the body and have rec...Bones are organs of the skeletal system, providing shape, mechanical support, and protection to the body and facilitating the movement. In addition, bones contribute to the mineral homeostasis of the body and have recently been found to participate in endocrine regulation of energy metabolism. The well-known limitations associated with clinical use of autografts and allografts continue to drive efforts to develop bone graft substitutes, using the principles of biomaterials and tissue engineering. Under some stressful and continuous compressive conditions, the ability of the bone tissue to tolerate strength decreases. Whenever these forces overcome the toleration of the bone tissue, bone fracture occurs. years展开更多
Lumbar degeneration leads to changes in geometry and density distribution of vertebrae,which could further influence the mechanical property and behavior.This study aimed to quantitatively describe the variations in s...Lumbar degeneration leads to changes in geometry and density distribution of vertebrae,which could further influence the mechanical property and behavior.This study aimed to quantitatively describe the variations in shape and density distribution for degenerated vertebrae by statistical models,and utilized the specific statistical shape model(SSM)/statistical appearance model(SAM)modes to assess compressive strength and fracture behavior.Highly detailed SSM and SAM were developed based on the 75 L1 vertebrae of elderly men,and their variations in shape and density distribution were quantified with principal component(PC)modes.All vertebrae were classified into mild(n=22),moderate(n=29),and severe(n=24)groups according to the overall degree of degeneration.Quantitative computed tomography-based finite element analysis was used to calculate compressive strength for each L1 vertebra,and the associations between compressive strength and PC modes were evaluated by multivariable linear regression(MLR).Moreover,the distributions of equivalent plastic strain(PEEQ)for the vertebrae assigned with the first modes of SSM and SAM at mean±3SD were investigated.The Leave-One-Out analysis showed that our SSM and SAM had good performance,with mean absolute errors of 0.335±0.084 mm and 64.610±26.620 mg/cm3,respectively.A reasonable accuracy of bone strength prediction was achieved by using four PC modes(SSM 1,SAM 1,SAM 4,and SAM 5)to construct the MLR model.Furthermore,the PEEQ values were more sensitive to degeneration-related variations of density distribution than those of morphology.The density variations may change the deformity type(compression deformity or wedge deformity),which further affects the fracture pattern.Statistical models can identify the morphology and density variations in degenerative vertebrae,and the SSM/SAM modes could be used to assess compressive strength and fracture behavior.The above findings have implications for assisting clinicians in pathological diagnosis,fracture risk assessment,implant design,and preoperative planning.展开更多
Purpose: Osteoporotic vertebral fractures with no sign of vertebral collapse on initial radiographs, which is so-called occult vertebral fractures (VFs), exist. Occult VFs have a high rate of missed diagnosis, and the...Purpose: Osteoporotic vertebral fractures with no sign of vertebral collapse on initial radiographs, which is so-called occult vertebral fractures (VFs), exist. Occult VFs have a high rate of missed diagnosis, and the treatment of these fractures has rarely been discussed in the literature. We evaluated the effects of vertebral bone drilling for the pain due to occults VFs. Materials and Methods: Eighteen patients with painful osteoporotic occult VFs underwent the vertebral bone drilling. We evaluated the clinical outcome by comparing numerical rating scale (NRS) and activity of daily life (ADL) values between before and after the vertebral bone drilling. Comparisons were made by using Wilcoxon signed rank test. Results: The mean baseline NRS and ADL score, and the mean NRS and ALD score after the bone drilling were 8.4 ± 0.8, 2.2 ± 0.6, 2.4 ± 1.0, 4.6 ± 0.5, respectively. Among the patients, we detected significant improvements in NRS pain score and ADL score after the drilling compared with baseline score (p < 0.0002). Conclusion: Vertebral bone drilling at the site of painful vertebral compression fractures alleviated the intractable pain due to osteoporotic occult VFs.展开更多
Objective: Unicameral bone cyst is a nonneoplasticbone lesion characterized by its tenacity and risk ofrecurrence. Pathological fracture is common and is often the presenting symptom. The objective of the present stud...Objective: Unicameral bone cyst is a nonneoplasticbone lesion characterized by its tenacity and risk ofrecurrence. Pathological fracture is common and is often the presenting symptom. The objective of the present study was to evaluate the results of hybrid external fixator for thetreatment of a unicameral bone cyst with a pathologicalfracture. Methods: Hybrid external fixator for thetreatment of a unicameral bone cyst was performed intwelve patients. These patients presented with a pathological fracture and were managed immediately with hybridexternal fixator, of whom four had been managedconservatively at other clinics before they were referred toour department. The cyst was located in the proximalhumerus in all patients. The mean age of the patients at the time of surgery was 8.7 years, and the mean duration offollow-up was 32.6 months. Radiographic evaluation wasperformed according to the criteria of Capanna et al., andthe cyst was classified as completely healed, healed withresidual radiolucency (osteolysis), recurred, or having noresponse. Results: The healing period ranged from three to eight months. Eight cysts healed completely, and threehealed with residual radiolucent areas visible onradiographs. There was recurrence of one cyst that hadhealed with residual radiolucency. All of the cysts in thepresent study responded to treatment. A modulation ofhybrid external fixator was necessary in three patients, asthe bars had become too short after bone growth or the pins had been loose. No major complications were observed.Conclusion: Hybrid external fixator provides earlystability, which allows early mobilization and thus obviates the need for a plaster cast. This method of treatment alsoallows for an early return to normal activity.展开更多
Bone connection with robot is an important topic in the research of robot assisted fracture reduction surgery.With the method to achieve bone-robot connection in current robots,requirements on reliability and low trau...Bone connection with robot is an important topic in the research of robot assisted fracture reduction surgery.With the method to achieve bone-robot connection in current robots,requirements on reliability and low trauma can not be satisfied at the same time.In this paper,the design,manufacturing,and experiments of a novel Bone Connection Robotic Hand(BCRH)with variable stiffness capability are carried out through the bionics research on human hand and the principle of particle jamming.BCRH’s variable stiffness characteristic is a special connection between“hard connection”and“soft connection”,which is different from the existing researches.It maximizes the reliability of bone-robot connection while minimizes trauma,meets the axial load requirement in clinical practice,and effectively shortens the operating time to less than 40 s(for mode 1)or 2 min(for mode 2).Meanwhile,a theoretical analysis of bone-robot connection failure based on particle jamming is carried out to provide references for the research in this paper and other related studies.展开更多
AIM： To examine whether vitamin D is of potential relevance in the healing process of fractures. METHODS： The present narrative review examined the bulk of the evidence based literature on the topic of vitamin D and...AIM： To examine whether vitamin D is of potential relevance in the healing process of fractures. METHODS： The present narrative review examined the bulk of the evidence based literature on the topic of vitamin D and bone healing in key electronic data bases from 1980 onwards using the terms vitamin D and bone healing, callus, fracture healing. All data were examined carefully and categorized according to type of study. A summary of the diverse terms and approaches employed in the research, as well as the rationale for hypothesizing vitamin D has a role in fracture healing was detailed.RESULTS： The results show very few human studies have been conducted to examine if vitamin D is effective at promoting post fracture healing, and the different ani-mal models that have been studied provide no consensus on this topic. The terms used in the related literature, as well as the methods used to arrive at conclusions on this clinical issue are highly diverse, there is no standardization of either of these important terms and methodolo-gies, hence no conclusive statements or clinical guide-lines can be forthcoming. There is a strong rational for continuing to examine if vitamin D supplements should be administered post-fracture, and ample evidence vitamin D is an essential hormone for functioning in general, as well as bone health and muscle as this relates to bone density.CONCLUSION： Whether those with low vitamin D levels can beneft from supplements if their nutritional practices do not cover recommended daily amounts, remains in question.展开更多
Background: Reduced bone density is a major risk factor for fragility fracture. Previous studies reported, that 69% to 100% of patients with fragility fractures had low bone mineral density (BMD). Objective: The objec...Background: Reduced bone density is a major risk factor for fragility fracture. Previous studies reported, that 69% to 100% of patients with fragility fractures had low bone mineral density (BMD). Objective: The objective of the study is to estimate the prevalence of osteoporosis and osteopenia among patients with fragility fractures. Results: The result of the study revealed that the mean age of patients included in the study was 65.11 ± 10.17 and the majority (77.3%) were females. The most common sites of fractures were the femur, radius and vertebra (30.7%, 17.0% and 14.8% respectively). Moreover, more than 95% of patients with fragility fracture who underwent BMD testing had low bone mineral density. In female with fragility fracture the prevalence of osteoporosis was higher in comparison to male (58.8% and 45.0% respectively). Conclusion: Our data showed that low BMD measurement is prevalent in patient with fragility fracture. It also highlighted the importance of implementation of Fracture liaison service, to reduce the gap between fragility fracture and osteoporosis treatment.展开更多
BACKGROUND Although percutaneous vertebral augmentation(PVA)is a commonly used procedure for treating vertebral compression fracture(VCF),the risk of vertebral refracture should be considered.Chronic kidney disease-mi...BACKGROUND Although percutaneous vertebral augmentation(PVA)is a commonly used procedure for treating vertebral compression fracture(VCF),the risk of vertebral refracture should be considered.Chronic kidney disease-mineral and bone disorder(CKD-MBD)is a systemic disease of mineral and bone metabolism.It is associated with an increased risk of fracture.Few studies have reported the use of PVA in patients with CKD-MBD.We herein report a rare case wherein the cemented vertebra and the adjacent vertebra refractured simultaneously in a CKD-MBD patient after PVA.CASE SUMMARY A 74-year-old man suffered from low back pain after taking a fall about 3 wk ago.According to physical examination,imaging and laboratory findings,diagnoses of T12 VCF,CKD-MBD,and chronic kidney disease stage 5 were established.He then received percutaneous vertebroplasty at T12 vertebra.Fourteen weeks later,he presented with T12 and L1 vertebral refractures caused by lumbar sprain.Once again,he was given PVA which was optimized for the refractured vertebrae.Although the short-term postoperative effect was satisfactory,he reported chronic low back pain again at the 3-month follow-up.CONCLUSION It is necessary that patients with CKD-MBD who have received PVA are aware of the adverse effects of CKD-MBD.It may increase the risk of vertebral refracture.Furthermore,the PVA surgical technique needs to be optimized according to the condition of the patient.The medium-and long-term effects of PVA remain uncertain in patients with CKD-MBD.展开更多
Objective:To study the calcaneal quantitative ultrasound-bone mineral density (QUS-BMD) value for evaluating bone metabolism and bone turnover in patients with osteoporotic fracture. Methods: A total of 150 patients w...Objective:To study the calcaneal quantitative ultrasound-bone mineral density (QUS-BMD) value for evaluating bone metabolism and bone turnover in patients with osteoporotic fracture. Methods: A total of 150 patients who were diagnosed with osteoporotic fracture in Nuclear Industry 417 Hospital between January 2010 and March 2017 were selected as the fracture group of the research, and 70 subjects with normal bone mineral density confirmed by physical examination during the same period were selected as the control group of the research. QUS-BMD apparatus was used to measure bone mineral density of calcaneus, and the serum was collected to determine the biochemical indexes of bone metabolism and bone turnover. Results:QUS-BMD value as well as serum BALP, OC, OPG levels of fracture group was significantly lower than those of control group while serum TRACP5b, RANKL, PINP, PICP, CTX and NTX levels were significantly higher than those of control group;serum BALP, OC, OPG levels of patients with osteoporosis and osteopenia were significantly lower than those of subjects with normal bone mass while TRACP5b, RANKL, PINP, PICP, CTX and NTX levels were significantly higher than those of subjects with normal bone mass;serum BALP, OC, OPG levels of patients with osteoporosis was significantly lower than those of patients with osteoporosis while TRACP5b, RANKL, PINP, PICP, CTX and NTX levels were significantly higher than those of patients with osteoporosis.Conclusion:Calcaneal QUS-BMD is valuable for evaluating the bone metabolism activity and bone turnover process in patients with osteoporotic fracture.展开更多
The aim of this study was to evaluate the number and distribution of fractures around the wrist found on bone scintigraphy in patients with a clinically suspected scaphoid fracture and negative initial radiographs. We...The aim of this study was to evaluate the number and distribution of fractures around the wrist found on bone scintigraphy in patients with a clinically suspected scaphoid fracture and negative initial radiographs. We retrospectively included 445 consecutive patients with a suspected scaphoid fracture who underwent routine bone scintigraphy. None of the radiographs showed evidence of a fracture. We analyzed the type and number of other fractures incidentally found on bone scintigraphy. On average, bone scintigraphy was done in 4 days (1 - 9). The outcome of bone scintigraphy: 80 (18.0%) a scaphoid fracture, 145 (32.6%) another fracture in the carpal region, 208 (46.7%) normal and the diagnosis of 12 (2.8%) was unclear. In the present study, we demonstrated that in patients with a clinically suspected scaphoid fracture and negative initial radiographs, bone scintigraphy detected in many cases (64.4%) other fractures in the carpal region. This suggests that radiographs not only miss scaphoid but also many other carpal and distal radius fractures. Solutions should be found to solve this problem and probably advanced imaging techniques like CT, MRI or bone scintigraphy should be used in the correct clinical scenario.展开更多
Objective: to analyze the main points of forensic identification of nasal bone fracture injury mechanism, fracture type, fresh or old fracture and imaging examination, so as to avoid the main points and countermeasure...Objective: to analyze the main points of forensic identification of nasal bone fracture injury mechanism, fracture type, fresh or old fracture and imaging examination, so as to avoid the main points and countermeasures of false identification, and provide reference for forensic identification. Methods: a total of 98 cases of nasal bone fracture injury identification completed after identification in the center from 2015 to 2020 were selected to analyze the missed diagnosis of nasal bone fracture, fracture type, composite injury, old and new fractures, injury mechanism and degree, and key points to avoid false identification. Results: most types of nasal bone fractures were accompanied by compound injuries: X-ray missed diagnosis and CT film reading were difficult;The key points of imaging diagnosis, the identification of old and new injuries, the grasp of the injury mechanism and degree of fracture, and how to avoid false identification are the key points of forensic identification.展开更多
Osteoporosis is a common metabolic skeletal disorder characterized by decreased bone mass and deteriorated bone structure, leading to increased susceptibility to fractures. With aging population, osteoporotic fracture...Osteoporosis is a common metabolic skeletal disorder characterized by decreased bone mass and deteriorated bone structure, leading to increased susceptibility to fractures. With aging population, osteoporotic fractures are of global health and socioeconomic importance. The three-dimensional microstructural information of the common osteoporosis-related fracture sites, including vertebra, femoral neck and distal radius, is a key for fully understanding osteoporosis pathogenesis and predicting the fracture risk. Low vertebral bone mineral density(BMD) is correlated with increased fracture of the spine. Vertebral BMD decreases from cervical to lumbar spine, with the lowest BMD at the third lumbar vertebra. Trabecular bone mass of the vertebrae is much lower than that of the peripheral bone. Cancellous bone of the vertebral body has a complex heterogeneous three-dimensional microstructure, with lower bone volume in the central and anterior superior regions. Trabecular bone quality is a key element to maintain the vertebral strength. The increased fragility of osteoporotic femoral neck is attributed to low cancellous bone volume and high compact porosity. Compared with age-matched controls, increased cortical porosity is observed at the femoral neck in osteoporoticfracture patients. Distal radius demonstrates spatial inhomogeneous characteristic in cortical microstructure. The medial region of the distal radius displays the highest cortical porosity compared with the lateral, anterior and posterior regions. Bone strength of the distal radius is mainly determined by cortical porosity, which deteriorates with advancing age.展开更多
Lower limb injures are frequently observed in passenger car traffic accidents.Previous studies of the injuries focus on long bone fractures by using either cadaver component tests or simulations of the long bone kinem...Lower limb injures are frequently observed in passenger car traffic accidents.Previous studies of the injuries focus on long bone fractures by using either cadaver component tests or simulations of the long bone kinematics,which lack in-depth study on the fractures in stress analysis.This paper aims to investigate lower limb impact biomechanics in real-world car to pedestrian accidents and to predict fractures of long bones in term of stress parameter for femur,tibia,and fibula.For the above purposes,a 3D finite element(FE) model of human body lower limb(HBM-LL) is developed based on human anatomy.The model consists of the pelvis,femur,tibia,fibula,patella,foot bones,primary tendons,knee joint capsule,meniscus,and ligaments.The FE model is validated by comparing the results from a lateral impact between simulations and tests with cadaver lower limb specimens.Two real-world accidents are selected from an in-depth accident database with detailed information about the accident scene,car impact speed,damage to the car,and pedestrian injuries.Multi-body system(MBS) models are used to reconstruct the kinematics of the pedestrians in the two accidents and the impact conditions are calculated for initial impact velocity and orientations of the car and pedestrian during the collision.The FE model is used to perform injury reconstructions and predict the fractures by using physical parameters,such as von Mises stress of long bones.The calculated failure level of the long bones is correlated with the injury outcomes observed from the two accident cases.The reconstruction result shows that the HBM-LL FE model has acceptable biofidelity and can be applied to predict the risk of long bone fractures.This study provides an efficient methodology to investigate the long bone fracture suffered from vehicle traffic collisions.展开更多
To enhance the fusion of graft bone in thoracolumbar vertebrae and minimize the postoperative loss of correction, short-segment pedicle screw fixation was reinforced with posterior moselizee bone grafting in vertebrae...To enhance the fusion of graft bone in thoracolumbar vertebrae and minimize the postoperative loss of correction, short-segment pedicle screw fixation was reinforced with posterior moselizee bone grafting in vertebrae for spinal fusion in patients with thoracrolumbar vertebrate fractures. Seventy patients with thoracrolumbar vertebrate fractures were treated by short-segment pedicle screw fixation and were randomly divided into two groups. Fractures in group A （n=20） were rein-forced with posterior morselized bone grafting in vertebrae for spinal fusion, while patients group B （n=50） did not receive the morselized bone grafting for bone fusion. The two groups were compared in terms of kyphotic deformity, anterior vertebral height, instrument failure and neurological functions after the treatment. Frankel grading system was used for the evaluation of neurological evaluation and Denis scoring scale was employed for pain assessment. The results showed that the kyphosis correction was achieved in both group A and group B （group A： 6.4 degree; group B： 5.4 degree）/At the end of follow-up, kyphosis correction was maintained in group A but lost in group B （P=0.0001）. Postoperatively, greater anterior height was achieved in group A than in group B （P〈0.01）. During follow-up study, anterior vertebral height was maintained only in Group A （P〈0.001）. Both group A and group B showed good Denis pain scores （P1 and P2） but group A outdid group B in terms of control of severe and constant pain （P4 and P5）. By Frankel criteria, the changes in neurological functions in group A was better than those of group B （P〈0.001）. It is concluded that reinforcement of short-segment pedicle fixation with morselized bone grafting for the treatment of patients with thoracolumbar vertebrae fracture could achieve and maintain kyphosis correction, and it may also increase and maintain anterior vertebral height. Morselized bone grafting in vertebrae offers immediate spinal stability in patients with thoracolumbar vertebrate fractures, decreases the instrument failure and provides better postoperative pain control than without the morselized bone grafting.展开更多
文摘BACKGROUND Tibial plateau fractures often require structural support for metaphyseal defects created during articular reduction.While autologous bone grafting has been utilized as the gold standard,bone substitutes offer advantages including reduced donor site morbidity.Our meta-analysis evaluated the comparative efficacy of these approaches across clinical and operative outcomes.AIM To conduct a systematic review and meta-analysis of randomized controlled trials comparing autologous bone grafts with bone substitutes for tibial plateau fractures.METHODS We conducted a systematic review and meta-analysis of randomized controlled trials comparing autologous bone grafts with bone substitutes for tibial plateau fractures.Primary outcomes included joint depression,secondary collapse rate,operative time,blood loss,and infection rate.Subgroup analyses were performed by fracture complexity,geographic region,and methodological factors.In addition to that,we also developed a combined outcome score integrating structural,procedural,and complication domains.RESULTS Seven randomized controlled trials with 424 patients(296 bone substitute,128 autograft)were included.No significant differences in joint depression or secondary collapse were observed across fracture complexity categories.Geographic variations were evident,with Western studies showing significantly higher risk of secondary collapse with autografts(risk ratio=1.45,P value=0.02).Both Western and Asian studies have demonstrated significantly reduced blood loss with bone substitutes(70-90 mL less),while operative time reduction was more significant in the Asian studies(23.65 vs 8.00 minutes,P value=0.04 for subgroup difference).The combined outcome score(standardized effect size-0.2481)favored bone substitutes,primarily due to procedural advantages.CONCLUSION Bone substitutes provide similar structural outcomes to autologous bone grafts while having better procedural advantages in tibial plateau fracture management.These findings support bone substitutes as a viable option across fracture patterns.Future studies should focus on specific bone substitute formulations and cost-effectiveness analyses.
基金Loma Linda Veterans Association for Research and EducationGrant/Award Number Seed Grant(to CR)+2 种基金US Department of Veterans AffairsGrant/Award Number Merit Review Award#5 I01 BX002519-04(to CR)Senior Research Career Scientist Award(to SM)。
文摘Objective: To better characterize nonunion endochondral bone healing and evaluate novel therapeutic approaches for critical size defect healing in clinically challenging bone repair, a segmental defect model of bone injury was adapted from the threepoint bending closed fracture technique in the murine femur.Methods: The mouse femur was surgically stabilized with an intramedullary threaded rod with plastic spacers and the defect adjusted to different sizes. Healing of the different defects was analyzed by radiology and histology to 8 weeks postsurgery. To determine whether this model was effective for evaluating the benefits of molecular therapy, BMP-2 was applied to the defect and healing then examined.Results: Intramedullary spacers were effective in maintaining the defect. Callus bone formation was initiated but was arrested at defect sizes of 2.5 mm and above, with no more progress in callus bone development evident to 8 weeks healing. Cartilage development in a critical size defect attenuated very early in healing without bone development, in contrast to the closed femur fracture healing, where callus cartilage was replaced by bone. BMP-2 therapy promoted osteogenesis of the resident cells of the defect, but there was no further callus development to indicate that healing to pre-surgery bone structure was successful.Conclusions: This segmental defect adaptation of the closed femur fracture model of murine bone repair severely impairs callus development and bone healing, reflecting a challenging bone injury. It is adjustable and can be compared to the closed fracture model to ascertain healing deficiencies and the efficacy of therapeutic approaches.
基金Supported by Jin-Wen Liu Academic Experience Heritage Studio Special Fund of National Famous Traditional Chinese Medicine,No.75.
文摘BACKGROUND Comminuted calcaneal fractures present significant treatment challenges.Open reduction and internal fixation carries risks such as infection and skin necrosis,while minimally invasive techniques may compromise reduction stability.Conservative management is generally limited to minimally displaced fractures.Traditional Chinese manual bone-setting has a long history in fracture treatment and is renowned globally for achieving functional reduction.It offers distinct advantages including lower cost,minimal soft tissue trauma,and the avoidance of expensive reduction equipment or internal fixation materials.CASE SUMMARY A 60-year-old female presented with left foot pain and limited mobility following a fall.Computed tomography scan revealed a Sanders type IV calcaneal fracture with a Böhler angle of 0°.A standardized,stepwise Traditional Chinese manual bone-setting was initially performed,followed by percutaneous screw fixation through several mini-incisions after satisfactory alignment was confirmed under fluoroscopy.The Visual Analog Scale score decreased from 5 on postoperative day 1 to 3 by day 3.The American Orthopaedic Foot and Ankle Society score improved from 73 at 6 weeks to 90 at 3 months,indicating rapid functional recovery and high patient satisfaction.At 7 months postoperatively,the American Orthopaedic Foot and Ankle Society score reached 95,prompting removal of internal fixation.At the 6-year follow-up,reduction remained well maintained,with the Böhler angle preserved at 22°.CONCLUSION The combination of Traditional Chinese manual bone-setting and percutaneous screw fixation achieved satisfactory functional reduction for comminuted calcaneal fractures.
基金Supported by National Natural Science Foundation of China(Grant Nos.52405001,52175001,62373010,82472537)China Postdoctoral Science Foundation(Grant No.2024M760166)+2 种基金Postdoctoral Fellowship Program of CPSF(Grant No.GZC20230186)Shenzhen Municipal Science,Technology,and Innovation Commission(Grant No.SGDX20220530111005036)Beijing Natural Science Foundation(Grant Nos.3222002,3232004,L222061).
文摘Long-bone fractures are common complaints in orthopedic surgery.In recent years,significant progress has been made in robot-assisted fracture-reduction techniques.As a key medical device for diverse fracture morphologies and sites,the design of the reduction robot has a profound impact on the reduction outcomes.However,existing reduction robots have practical limitations and cannot simultaneously satisfy clinical requirements in terms of workspace,force/torque,and structural stiffness.To overcome these problems,we first analyze the potential placement areas and performance requirements of reduction robots according to clinical application scenarios.Subsequently,a 3UPS/S-3P hybrid configuration with decoupled rotational and translational degrees of freedom(DOFs)is proposed,and a kinematic model is derived to achieve the motion characteristics of the remote center of motion(RCM).Furthermore,the structural design of a hybrid reduction robot with an integrated distal clamp and proximal fixator was completed,and a mechanical prototype was constructed.The results of the performance evaluations and static analysis demonstrate that the proposed reduction robot has acceptable workspace,force,and torque performance and excellent structural stiffness.Two clinical case simulations further demonstrated the clinical feasibility of the robot.Finally,preliminary experiments on bone models demonstrated the potential effectiveness of the proposed reduction robot in lower-limb fracture reduction.
文摘A monoclonal antibody raised against bone morphogenetic protein (BMP-McAb) has been used to demonstrate the presence of bone morphogenetic protein(BMP) in experimental fracture healing. Rabbit mandibles were fractured using standardized methods and left to heal for 3, 7, 14, 21 and 24 d, respectively. The avidin-biotin complex (ABC) method demonstrated an accumulation of positively stained primitive mesenchymal cells at the fracture site in the hematoma stage of bone repair. These cells appeared to undergo differentiation into positively-stained chondroblasts and osteoblasts during the phase of callus formation. Undifferentiated mesenchymal cells showed a high positive reactivity in the early post-fracture stages but a much lower reactivity during the remodelling phase.The results of our study suggest that bone inductive processes are accompanied by the presence of BMP in osteoprogenitor cells during fracture healing of the mandible and that BMP may play a significant role in osteogenesis during bone healing.
文摘BACKGROUND The National Institute for Health and Care Excellence(NICE)guidelines have advised further research is required into investigating the added prognostic value of bone mineral density(BMD)in the assessment of fracture risk with the Fracture Risk Assessment Tool(FRAX)score.AIM To investigate the significance of BMD in fracture neck of femur patients and compare it to the outcome of the FRAX score.METHODS Inclusion criteria for this study were all patients who underwent dual-energy Xray absorptiometry(DXA)scan following fracture neck of femur between 2015 and 2017.Analysis of BMD,FRAX scores and patient demographic data was undertaken.RESULTS A total of 69 patients were included in the study,mean age 74.1 years.There was no significant difference between mean BMD of the femoral neck in males(0.65)as compared to females(0.61)(P=0.364).Analyses showed no significant correlation between BMD and menopause age(rs=-0.28,P=0.090).A significant difference was seen of the femoral neck BMD between the different fracture pattern types(P=0.026).A stronger correlation was observed between BMD of femoral neck and FRAX major score(rs=-0.64,P<0.001)than with BMD of lumbar spine and FRAX major score(rs=-0.37,P=0.003).CONCLUSION This study demonstrated that BMD of the femoral neck measured by DXA scan is of added prognostic value when assessing patients for risk of fracture neck of femur in combination with the FRAX predictive scoring system.
文摘Bones are organs of the skeletal system, providing shape, mechanical support, and protection to the body and facilitating the movement. In addition, bones contribute to the mineral homeostasis of the body and have recently been found to participate in endocrine regulation of energy metabolism. The well-known limitations associated with clinical use of autografts and allografts continue to drive efforts to develop bone graft substitutes, using the principles of biomaterials and tissue engineering. Under some stressful and continuous compressive conditions, the ability of the bone tissue to tolerate strength decreases. Whenever these forces overcome the toleration of the bone tissue, bone fracture occurs. years
基金supported by the National Natural Science Foundation of China(Grant No.12272029).
文摘Lumbar degeneration leads to changes in geometry and density distribution of vertebrae,which could further influence the mechanical property and behavior.This study aimed to quantitatively describe the variations in shape and density distribution for degenerated vertebrae by statistical models,and utilized the specific statistical shape model(SSM)/statistical appearance model(SAM)modes to assess compressive strength and fracture behavior.Highly detailed SSM and SAM were developed based on the 75 L1 vertebrae of elderly men,and their variations in shape and density distribution were quantified with principal component(PC)modes.All vertebrae were classified into mild(n=22),moderate(n=29),and severe(n=24)groups according to the overall degree of degeneration.Quantitative computed tomography-based finite element analysis was used to calculate compressive strength for each L1 vertebra,and the associations between compressive strength and PC modes were evaluated by multivariable linear regression(MLR).Moreover,the distributions of equivalent plastic strain(PEEQ)for the vertebrae assigned with the first modes of SSM and SAM at mean±3SD were investigated.The Leave-One-Out analysis showed that our SSM and SAM had good performance,with mean absolute errors of 0.335±0.084 mm and 64.610±26.620 mg/cm3,respectively.A reasonable accuracy of bone strength prediction was achieved by using four PC modes(SSM 1,SAM 1,SAM 4,and SAM 5)to construct the MLR model.Furthermore,the PEEQ values were more sensitive to degeneration-related variations of density distribution than those of morphology.The density variations may change the deformity type(compression deformity or wedge deformity),which further affects the fracture pattern.Statistical models can identify the morphology and density variations in degenerative vertebrae,and the SSM/SAM modes could be used to assess compressive strength and fracture behavior.The above findings have implications for assisting clinicians in pathological diagnosis,fracture risk assessment,implant design,and preoperative planning.
文摘Purpose: Osteoporotic vertebral fractures with no sign of vertebral collapse on initial radiographs, which is so-called occult vertebral fractures (VFs), exist. Occult VFs have a high rate of missed diagnosis, and the treatment of these fractures has rarely been discussed in the literature. We evaluated the effects of vertebral bone drilling for the pain due to occults VFs. Materials and Methods: Eighteen patients with painful osteoporotic occult VFs underwent the vertebral bone drilling. We evaluated the clinical outcome by comparing numerical rating scale (NRS) and activity of daily life (ADL) values between before and after the vertebral bone drilling. Comparisons were made by using Wilcoxon signed rank test. Results: The mean baseline NRS and ADL score, and the mean NRS and ALD score after the bone drilling were 8.4 ± 0.8, 2.2 ± 0.6, 2.4 ± 1.0, 4.6 ± 0.5, respectively. Among the patients, we detected significant improvements in NRS pain score and ADL score after the drilling compared with baseline score (p < 0.0002). Conclusion: Vertebral bone drilling at the site of painful vertebral compression fractures alleviated the intractable pain due to osteoporotic occult VFs.
文摘Objective: Unicameral bone cyst is a nonneoplasticbone lesion characterized by its tenacity and risk ofrecurrence. Pathological fracture is common and is often the presenting symptom. The objective of the present study was to evaluate the results of hybrid external fixator for thetreatment of a unicameral bone cyst with a pathologicalfracture. Methods: Hybrid external fixator for thetreatment of a unicameral bone cyst was performed intwelve patients. These patients presented with a pathological fracture and were managed immediately with hybridexternal fixator, of whom four had been managedconservatively at other clinics before they were referred toour department. The cyst was located in the proximalhumerus in all patients. The mean age of the patients at the time of surgery was 8.7 years, and the mean duration offollow-up was 32.6 months. Radiographic evaluation wasperformed according to the criteria of Capanna et al., andthe cyst was classified as completely healed, healed withresidual radiolucency (osteolysis), recurred, or having noresponse. Results: The healing period ranged from three to eight months. Eight cysts healed completely, and threehealed with residual radiolucent areas visible onradiographs. There was recurrence of one cyst that hadhealed with residual radiolucency. All of the cysts in thepresent study responded to treatment. A modulation ofhybrid external fixator was necessary in three patients, asthe bars had become too short after bone growth or the pins had been loose. No major complications were observed.Conclusion: Hybrid external fixator provides earlystability, which allows early mobilization and thus obviates the need for a plaster cast. This method of treatment alsoallows for an early return to normal activity.
基金This research was supported by the National Natural Science Foundation of China(Grant Nos.51975070,62003060 and 52075051)the National Key Research and Development Program of China(Grant No.2020YFB1313000).
文摘Bone connection with robot is an important topic in the research of robot assisted fracture reduction surgery.With the method to achieve bone-robot connection in current robots,requirements on reliability and low trauma can not be satisfied at the same time.In this paper,the design,manufacturing,and experiments of a novel Bone Connection Robotic Hand(BCRH)with variable stiffness capability are carried out through the bionics research on human hand and the principle of particle jamming.BCRH’s variable stiffness characteristic is a special connection between“hard connection”and“soft connection”,which is different from the existing researches.It maximizes the reliability of bone-robot connection while minimizes trauma,meets the axial load requirement in clinical practice,and effectively shortens the operating time to less than 40 s(for mode 1)or 2 min(for mode 2).Meanwhile,a theoretical analysis of bone-robot connection failure based on particle jamming is carried out to provide references for the research in this paper and other related studies.
文摘AIM： To examine whether vitamin D is of potential relevance in the healing process of fractures. METHODS： The present narrative review examined the bulk of the evidence based literature on the topic of vitamin D and bone healing in key electronic data bases from 1980 onwards using the terms vitamin D and bone healing, callus, fracture healing. All data were examined carefully and categorized according to type of study. A summary of the diverse terms and approaches employed in the research, as well as the rationale for hypothesizing vitamin D has a role in fracture healing was detailed.RESULTS： The results show very few human studies have been conducted to examine if vitamin D is effective at promoting post fracture healing, and the different ani-mal models that have been studied provide no consensus on this topic. The terms used in the related literature, as well as the methods used to arrive at conclusions on this clinical issue are highly diverse, there is no standardization of either of these important terms and methodolo-gies, hence no conclusive statements or clinical guide-lines can be forthcoming. There is a strong rational for continuing to examine if vitamin D supplements should be administered post-fracture, and ample evidence vitamin D is an essential hormone for functioning in general, as well as bone health and muscle as this relates to bone density.CONCLUSION： Whether those with low vitamin D levels can beneft from supplements if their nutritional practices do not cover recommended daily amounts, remains in question.
文摘Background: Reduced bone density is a major risk factor for fragility fracture. Previous studies reported, that 69% to 100% of patients with fragility fractures had low bone mineral density (BMD). Objective: The objective of the study is to estimate the prevalence of osteoporosis and osteopenia among patients with fragility fractures. Results: The result of the study revealed that the mean age of patients included in the study was 65.11 ± 10.17 and the majority (77.3%) were females. The most common sites of fractures were the femur, radius and vertebra (30.7%, 17.0% and 14.8% respectively). Moreover, more than 95% of patients with fragility fracture who underwent BMD testing had low bone mineral density. In female with fragility fracture the prevalence of osteoporosis was higher in comparison to male (58.8% and 45.0% respectively). Conclusion: Our data showed that low BMD measurement is prevalent in patient with fragility fracture. It also highlighted the importance of implementation of Fracture liaison service, to reduce the gap between fragility fracture and osteoporosis treatment.
文摘BACKGROUND Although percutaneous vertebral augmentation(PVA)is a commonly used procedure for treating vertebral compression fracture(VCF),the risk of vertebral refracture should be considered.Chronic kidney disease-mineral and bone disorder(CKD-MBD)is a systemic disease of mineral and bone metabolism.It is associated with an increased risk of fracture.Few studies have reported the use of PVA in patients with CKD-MBD.We herein report a rare case wherein the cemented vertebra and the adjacent vertebra refractured simultaneously in a CKD-MBD patient after PVA.CASE SUMMARY A 74-year-old man suffered from low back pain after taking a fall about 3 wk ago.According to physical examination,imaging and laboratory findings,diagnoses of T12 VCF,CKD-MBD,and chronic kidney disease stage 5 were established.He then received percutaneous vertebroplasty at T12 vertebra.Fourteen weeks later,he presented with T12 and L1 vertebral refractures caused by lumbar sprain.Once again,he was given PVA which was optimized for the refractured vertebrae.Although the short-term postoperative effect was satisfactory,he reported chronic low back pain again at the 3-month follow-up.CONCLUSION It is necessary that patients with CKD-MBD who have received PVA are aware of the adverse effects of CKD-MBD.It may increase the risk of vertebral refracture.Furthermore,the PVA surgical technique needs to be optimized according to the condition of the patient.The medium-and long-term effects of PVA remain uncertain in patients with CKD-MBD.
文摘Objective:To study the calcaneal quantitative ultrasound-bone mineral density (QUS-BMD) value for evaluating bone metabolism and bone turnover in patients with osteoporotic fracture. Methods: A total of 150 patients who were diagnosed with osteoporotic fracture in Nuclear Industry 417 Hospital between January 2010 and March 2017 were selected as the fracture group of the research, and 70 subjects with normal bone mineral density confirmed by physical examination during the same period were selected as the control group of the research. QUS-BMD apparatus was used to measure bone mineral density of calcaneus, and the serum was collected to determine the biochemical indexes of bone metabolism and bone turnover. Results:QUS-BMD value as well as serum BALP, OC, OPG levels of fracture group was significantly lower than those of control group while serum TRACP5b, RANKL, PINP, PICP, CTX and NTX levels were significantly higher than those of control group;serum BALP, OC, OPG levels of patients with osteoporosis and osteopenia were significantly lower than those of subjects with normal bone mass while TRACP5b, RANKL, PINP, PICP, CTX and NTX levels were significantly higher than those of subjects with normal bone mass;serum BALP, OC, OPG levels of patients with osteoporosis was significantly lower than those of patients with osteoporosis while TRACP5b, RANKL, PINP, PICP, CTX and NTX levels were significantly higher than those of patients with osteoporosis.Conclusion:Calcaneal QUS-BMD is valuable for evaluating the bone metabolism activity and bone turnover process in patients with osteoporotic fracture.
文摘The aim of this study was to evaluate the number and distribution of fractures around the wrist found on bone scintigraphy in patients with a clinically suspected scaphoid fracture and negative initial radiographs. We retrospectively included 445 consecutive patients with a suspected scaphoid fracture who underwent routine bone scintigraphy. None of the radiographs showed evidence of a fracture. We analyzed the type and number of other fractures incidentally found on bone scintigraphy. On average, bone scintigraphy was done in 4 days (1 - 9). The outcome of bone scintigraphy: 80 (18.0%) a scaphoid fracture, 145 (32.6%) another fracture in the carpal region, 208 (46.7%) normal and the diagnosis of 12 (2.8%) was unclear. In the present study, we demonstrated that in patients with a clinically suspected scaphoid fracture and negative initial radiographs, bone scintigraphy detected in many cases (64.4%) other fractures in the carpal region. This suggests that radiographs not only miss scaphoid but also many other carpal and distal radius fractures. Solutions should be found to solve this problem and probably advanced imaging techniques like CT, MRI or bone scintigraphy should be used in the correct clinical scenario.
文摘Objective: to analyze the main points of forensic identification of nasal bone fracture injury mechanism, fracture type, fresh or old fracture and imaging examination, so as to avoid the main points and countermeasures of false identification, and provide reference for forensic identification. Methods: a total of 98 cases of nasal bone fracture injury identification completed after identification in the center from 2015 to 2020 were selected to analyze the missed diagnosis of nasal bone fracture, fracture type, composite injury, old and new fractures, injury mechanism and degree, and key points to avoid false identification. Results: most types of nasal bone fractures were accompanied by compound injuries: X-ray missed diagnosis and CT film reading were difficult;The key points of imaging diagnosis, the identification of old and new injuries, the grasp of the injury mechanism and degree of fracture, and how to avoid false identification are the key points of forensic identification.
文摘Osteoporosis is a common metabolic skeletal disorder characterized by decreased bone mass and deteriorated bone structure, leading to increased susceptibility to fractures. With aging population, osteoporotic fractures are of global health and socioeconomic importance. The three-dimensional microstructural information of the common osteoporosis-related fracture sites, including vertebra, femoral neck and distal radius, is a key for fully understanding osteoporosis pathogenesis and predicting the fracture risk. Low vertebral bone mineral density(BMD) is correlated with increased fracture of the spine. Vertebral BMD decreases from cervical to lumbar spine, with the lowest BMD at the third lumbar vertebra. Trabecular bone mass of the vertebrae is much lower than that of the peripheral bone. Cancellous bone of the vertebral body has a complex heterogeneous three-dimensional microstructure, with lower bone volume in the central and anterior superior regions. Trabecular bone quality is a key element to maintain the vertebral strength. The increased fragility of osteoporotic femoral neck is attributed to low cancellous bone volume and high compact porosity. Compared with age-matched controls, increased cortical porosity is observed at the femoral neck in osteoporoticfracture patients. Distal radius demonstrates spatial inhomogeneous characteristic in cortical microstructure. The medial region of the distal radius displays the highest cortical porosity compared with the lateral, anterior and posterior regions. Bone strength of the distal radius is mainly determined by cortical porosity, which deteriorates with advancing age.
基金supported by National Hi-tech Research and Development Program of China (863 Program,Grant No. 2006AA110101)"111 Program" of Ministry of Education and State Administration of Foreign Experts Affairs of China (Grant No. 111-2-11)+1 种基金General Motors Research and Development Center (Grant No. RD-209)Project of State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body,Hunan University,China (Grant No. 60870004)
文摘Lower limb injures are frequently observed in passenger car traffic accidents.Previous studies of the injuries focus on long bone fractures by using either cadaver component tests or simulations of the long bone kinematics,which lack in-depth study on the fractures in stress analysis.This paper aims to investigate lower limb impact biomechanics in real-world car to pedestrian accidents and to predict fractures of long bones in term of stress parameter for femur,tibia,and fibula.For the above purposes,a 3D finite element(FE) model of human body lower limb(HBM-LL) is developed based on human anatomy.The model consists of the pelvis,femur,tibia,fibula,patella,foot bones,primary tendons,knee joint capsule,meniscus,and ligaments.The FE model is validated by comparing the results from a lateral impact between simulations and tests with cadaver lower limb specimens.Two real-world accidents are selected from an in-depth accident database with detailed information about the accident scene,car impact speed,damage to the car,and pedestrian injuries.Multi-body system(MBS) models are used to reconstruct the kinematics of the pedestrians in the two accidents and the impact conditions are calculated for initial impact velocity and orientations of the car and pedestrian during the collision.The FE model is used to perform injury reconstructions and predict the fractures by using physical parameters,such as von Mises stress of long bones.The calculated failure level of the long bones is correlated with the injury outcomes observed from the two accident cases.The reconstruction result shows that the HBM-LL FE model has acceptable biofidelity and can be applied to predict the risk of long bone fractures.This study provides an efficient methodology to investigate the long bone fracture suffered from vehicle traffic collisions.
文摘To enhance the fusion of graft bone in thoracolumbar vertebrae and minimize the postoperative loss of correction, short-segment pedicle screw fixation was reinforced with posterior moselizee bone grafting in vertebrae for spinal fusion in patients with thoracrolumbar vertebrate fractures. Seventy patients with thoracrolumbar vertebrate fractures were treated by short-segment pedicle screw fixation and were randomly divided into two groups. Fractures in group A （n=20） were rein-forced with posterior morselized bone grafting in vertebrae for spinal fusion, while patients group B （n=50） did not receive the morselized bone grafting for bone fusion. The two groups were compared in terms of kyphotic deformity, anterior vertebral height, instrument failure and neurological functions after the treatment. Frankel grading system was used for the evaluation of neurological evaluation and Denis scoring scale was employed for pain assessment. The results showed that the kyphosis correction was achieved in both group A and group B （group A： 6.4 degree; group B： 5.4 degree）/At the end of follow-up, kyphosis correction was maintained in group A but lost in group B （P=0.0001）. Postoperatively, greater anterior height was achieved in group A than in group B （P〈0.01）. During follow-up study, anterior vertebral height was maintained only in Group A （P〈0.001）. Both group A and group B showed good Denis pain scores （P1 and P2） but group A outdid group B in terms of control of severe and constant pain （P4 and P5）. By Frankel criteria, the changes in neurological functions in group A was better than those of group B （P〈0.001）. It is concluded that reinforcement of short-segment pedicle fixation with morselized bone grafting for the treatment of patients with thoracolumbar vertebrae fracture could achieve and maintain kyphosis correction, and it may also increase and maintain anterior vertebral height. Morselized bone grafting in vertebrae offers immediate spinal stability in patients with thoracolumbar vertebrate fractures, decreases the instrument failure and provides better postoperative pain control than without the morselized bone grafting.
