BACKGROUND The recovery of limb function after ankle fracture surgery is a gradual process.The main purpose of implementing early functional exercise,joint mobility,muscle contraction function,passive ankle flexion an...BACKGROUND The recovery of limb function after ankle fracture surgery is a gradual process.The main purpose of implementing early functional exercise,joint mobility,muscle contraction function,passive ankle flexion and extension exercises,or physical factor therapy techniques is to achieve the rapid recovery of normal physiological limb function.However,currently the most effective rehabilitation training method is staged limb functional exercise,which promotes rapid recovery of limb function while preventing adverse consequences caused by overwork or insufficient training.Staged limb functional exercise divides the rehabilitation process into multiple stages,each of which has specific training objectives and contents.This method helps patients gradually restore limb function.Nevertheless,some patients still exhibit poor limb function after standardized exercise.Therefore,a functional evaluation should be performed to analyze the impact of staged functional training after ankle fracture surgery.AIM To perform a functional evaluation and determine the influencing factors of staged functional training in patients with ankle fracture.METHODS A retrospective study enrolled 150 patients who underwent surgical treatment for ankle fracture from May 2020 to May 2022 at our hospital.Univariate and multivariate linear regression analyses were performed on general data,functional exercise compliance scale for orthopedic patients,Social Support Rating Scale(SSRS),American Orthopedic Foot and Ankle Score(AOFAS)Ankle-Hindfoot Score,and pain factors[serum bradykinin(BK),prostaglandin E2(PGE2),5-hydroxytryptamine(5-HT)].RESULTS Based on the AOFAS Ankle-Hindfoot Scale,the cases were divided into the excellent function(n=111)and ordinary function(n=39)groups.Univariate analysis revealed that monthly family income,education level,diabetes mellitus,functional exercise compliance scale of orthopedic patients score,SSRS,BK,PGE2,and 5-HT significantly influenced limb function after ankle fracture(P<0.05);Multiple linear regression analysis showed that the functional exercise compliance scale score,SSRS,BK,PGE2,and 5-HT were independent risk factors affecting functional performance after staged functional exercise(P<0.05).CONCLUSION Exercise compliance,SSRS,and pain level are the independent risk factors affecting functional performance after staged functional training following ankle surgery.Clinical nursing care after ankle surgery should include analgesic and health education measures to ensure optimal recovery of limb function.展开更多
Introduction and Background: Ankle injury is one of the most frequent presenting injuries to the emergency room and ankle fractures are common fracture in the lower limbs injuries that may require operative treatment ...Introduction and Background: Ankle injury is one of the most frequent presenting injuries to the emergency room and ankle fractures are common fracture in the lower limbs injuries that may require operative treatment with variable outcomes. Materials and Methods: Sixty-three patients were included in my retrospective study, and all with a displaced fracture of the ankle caused by high energy trauma were treated by open reduction and rigid internal fixation. Results: After follow-up at six weeks and twelve weeks, the results were satisfactory in fifty-five percent out of all the sixty-three patients. Conclusions and Recommendations: Ankle fractures occur mainly in young males of the age group between 26 and 35 years, mostly caused by fall down and motor vehicle accident.展开更多
BACKGROUND Open fractures of the ankle are complex injuries requiring multidisciplinary input and are associated with significant morbidity and mortality.However,data on the clinical outcomes of open ankle fracture ma...BACKGROUND Open fractures of the ankle are complex injuries requiring multidisciplinary input and are associated with significant morbidity and mortality.However,data on the clinical outcomes of open ankle fracture management in patients older than 70 is minimal.AIM To evaluate the clinical outcomes following open ankle fracture management in patients older than 70.Our secondary aim is to look at predictors of poor outcomes.METHODS Following local research and audit department registration,22 years of prospectively collated data from an electronic database in a district general hospital were assessed.All patients older than 70 years of age with an open ankle fracture requiring surgical intervention were identified.Demographic information,the nature,and the number of surgical interventions were collated.Complications,including surgical site infection(SSI),venous thromboembolic events(VTEs)during hospital stay,and mortality rate,were reviewed.RESULTS A total of 37 patients were identified(median age:84 years,range:70-98);n=30 females median age:84 years,range:70-97);n=7 males median age:74 years,range:71-98))who underwent surgical intervention after an open ankle fracture.Sixteen patients developed SSIs(43%).Superficial SSIs(n=8)were managed without surgical intervention and treated with antibiotics and regular dressing changes.Deep SSIs(n=8;20%)required a median of 3(range:2-9)surgical interventions,with four patients requiring multiple washouts and one patient having metalwork removed.VTE incidence was 5%during the hospital stay.Eight patients died within 30 d,and mortality at one year was 19%.The 10-year mortality rate was 57%.The presence of a history of stroke,cancer,or prolonged inpatient stay was found to be predictive of lower survivorship in this population(log-rank test:cancer P=0.008,stroke P=0.001,length of stay>33 d P=0.015).The presence of a cardiac history was predictive of wound complications(logistic regression,P=0.045).Age,number of operations,and diabetic history were found to be predictive of an increase in the length of stay(general linear model;age P<0.001,number of operations P<0.001,diabetes P=0.041).CONCLUSION An open ankle fracture in a patient older than 70 years has at least a 20%chance of requiring repeated surgical intervention due to deep SSIs.The presence of a cardiac history appears to be the main predictor for wound complications.展开更多
Objective:To analyze the value of applying evidence-based nursing in the perioperative care of patients with ankle fractures and propose corresponding measures to improve the quality of patient care.Methods:The study ...Objective:To analyze the value of applying evidence-based nursing in the perioperative care of patients with ankle fractures and propose corresponding measures to improve the quality of patient care.Methods:The study started in May 2022 and was terminated in March 2023.During this period,50 patients with ankle fractures treated by our hospital were selected as research subjects.They were divided into a control group and a research group.The control group had 25 patients who received routine care,and the research group had 25 who received evidence-based care.The nursing effects of the two groups were observed and compared.Results:The pain scores,quality of life,incidence of adverse reactions,and nursing satisfaction of patients in the research group were all significantly better than those in the control group(P<0.05).Conclusion:Evidence-based nursing can effectively improve the quality of care,reduce the risk of adverse reactions,and promote patient recovery,so it is suitable for clinical implementation.展开更多
BACKGROUND Locking plate fixation in osteoporotic ankle fractures may fail due to cut-out or metalwork failure.Fibula pro-tibia fixation was a technique prior to the advent of locking plates that was used to enhance s...BACKGROUND Locking plate fixation in osteoporotic ankle fractures may fail due to cut-out or metalwork failure.Fibula pro-tibia fixation was a technique prior to the advent of locking plates that was used to enhance stability in ankle fractures by achieving tri or tetra-cortical fixation.With locking plates,the strength of this fixation construct can be further enhanced.There is lack of evidence currently on the merits of tibiapro-fibula augmented locking plate fixation of unstable ankle fractures.AIM To assess if there is increased strength to failure,in an ankle fracture saw bone model,with a fibula pro-tibia construct when compared with standard locking plate fixation.METHODS Ten osteoporotic saw bones with simulated supination external rotation injuries were used.Five saw bones were fixed with standard locking plates whilst the other 5 saw bones were fixed with locking plates in a fibula pro-tibia construct.The fibula pro-tibia construct involved fixation with 3 consecutive locking screws applied across 3 cortices proximally from the level of the syndesmosis.All fixations were tested in axial external rotation to failure on an electromagnetic test frame(MTS 858 Mini-Bionix test machine,MTS Corp,Eden Praire,MN,United States).Torque at 30 degrees external rotation,failure torque,and external rotation angle at failure were compared between both groups and statistically analyzed.RESULTS The fibula pro-tibia construct demonstrated a statistically higher torque at 30 degrees external rotation(4.421±0.796 N/m vs 1.451±0.467 N/m;t-test P=0.000),as well as maximum torque at failure(5.079±0.694N/m vs 2.299±0.931 N/m;t-test P=0.001)compared to the standard locking plate construct.The fibula pro-tibia construct also had a lower external rotation angle at failure(54.7±14.5 vs 67.7±22.9).CONCLUSION The fibula pro-tibia locking plate construct demonstrates biomechanical superiority to standard locking plates in fixation of unstable ankle fractures in this saw bone model.There is merit in the use of this construct in patients with unstable osteoporotic ankle fractures as it may aid improved clinical outcomes.展开更多
AIM: To report ankle fracture configurations and bone quality following arthroscopic-assisted reduction and internal-fixation(ARIF) or open reduction and internalfixation(ORIF). METHODS: The patients of ARIF(n = 16) o...AIM: To report ankle fracture configurations and bone quality following arthroscopic-assisted reduction and internal-fixation(ARIF) or open reduction and internalfixation(ORIF). METHODS: The patients of ARIF(n = 16) or ORIF(n = 29) to treat unstable ankle fracture between 2006 and 2014 were reviewed retrospectively. Baseline data, including age, sex, type of injury, immediate postoperative fracture configuration(assessed on X-rays and graded by widest gap and largest step-off of any intraarticular site), bone quality [assessed with bone mineral density(BMD) testing] and arthritic changes on X-rays following surgical treatments were recorded for each group.RESULTS: Immediate-postoperative fracture configurations did not differ significantly between the ARIF and ORIF groups. There were anatomic alignments as 8(50%) and 8(27.6%) patients in ARIF and ORIF groups(P = 0.539) respectively. There were acceptable alignments as 12(75%) and 17(58.6%) patients in ARIF and ORIF groups(P = 0.341) respectively. The arthritic changes in follow-up period as at least 16 wk following the surgeries were shown as 6(75%) and 10(83.3%) patients in ARIF and ORIF groups(P = 0.300) respectively. Significantly more BMD tests were performed in patients aged > 60 years(P < 0.001), ARIF patients(P = 0.021), and female patients(P = 0.029). There was no significant difference in BMD test t scores between the two groups. CONCLUSION: Ankle fracture configurations following surgeries are similar between ARIF and ORIF groups, suggesting that ARIF is not superior to ORIF in treatment of unstable ankle fractures.展开更多
Ankle fractures are one of the most common injuries treated by orthopaedic surgeons. A minority of patients with ankle fractures go on to develop persistent pain following anatomical reduction. These sequelae may aris...Ankle fractures are one of the most common injuries treated by orthopaedic surgeons. A minority of patients with ankle fractures go on to develop persistent pain following anatomical reduction. These sequelae may arise as a result of untreated ligamentous or chondral injuries. This study aims to correlate acute arthroscopic ankle findings with the <i><span>Lauge-Hansen </span></i><span>fracture pattern classification. We further aim to compare subjective functional outcomes at least one year following surgery between patients who have received Open Reduction and Internal Fixation (ORIF) alone, </span><b><i><span>versus</span></i></b><i><span> </span></i><span>ORIF </span><i><span>plus</span></i><span> arthroscopy. This is a retrospective case series of patients who have undergone ankle fracture ORIF +/</span><span>-</span><span> arthroscopy from July 2014 to July 2017 inclusive. Each patient’s presenting radiograph was classified according to the </span><i><span>Lauge-Hansen</span></i><span> ankle fracture classification with subsequent correlation to intra-operative arthroscopic findings. Functional outcome at a minimum of one year was evaluated with the American Academy of Orthopaedic Surgeons (AAOS) metric. Twenty two patients underwent ankle ORIF plus arthroscopy (Group A) with a further 26 patients receiving ORIF alone (Group B). 1 in 3 supination-external-rotation type II (SER II) injuries possessed a concomitant syndesmosis injury or osteochondral lesion (OCL) on arthroscopy. 1 in 3 patients with a</span><span>n</span><span> SER IV injury had an osteochondral lesion. The mean AAOS score achieved for Group A was 89.6 (±7.9) with the mean score for Group B being 82.0 (±13.7). In conclusion, ankle arthroscopy aids the diagnosis and treatment of ligamentous and osteochondral injuries not evident on plain film with subsequent superior short-term outcomes</span><span>.</span>展开更多
Treatment of fragility fractures of the distal tibia in the elderly is demanding because of osteopenic bone quality, the delicate soft tissue cuff and </span></span></span></span><span style...Treatment of fragility fractures of the distal tibia in the elderly is demanding because of osteopenic bone quality, the delicate soft tissue cuff and </span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">frequent</span></span></span></span></span><span><span><span><span><span style="font-family:""><span style="font-family:Verdana;"> crit</span><span style="font-family:Verdana;">ical circulation. We report the case of two-level tibial pseudarthroses in an</span><span style="font-family:Verdana;"> 83</span></span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">- </span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">year</span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span></span></span><span><span><span><span><span style="font-family:""><span style="font-family:Verdana;">old woman caused by multiple myeloma successfully stabilized by a long </span><span style="font-family:Verdana;">ankle arthrodesis nail combined with locking compression plate</span> <span style="font-family:Verdana;">osteosynthesis. This case is unique</span></span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> as to our best knowledge</span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> herein</span></span></span></span></span><span><span><span><span><span style="font-family:""><span style="font-family:Verdana;"> diaphyseal fractures were </span><span style="font-family:Verdana;">treated for the first time using a technique reported hitherto primarily for</span><span style="font-family:Verdana;"> fragility ankle and pilon fractures.展开更多
The precise diagnosis of distal tibiofibular syndesmotic ligament injury is challenging and a distinction should be made between syndesmotic ligament disruption and real syndesmotic instability.This article summarizes...The precise diagnosis of distal tibiofibular syndesmotic ligament injury is challenging and a distinction should be made between syndesmotic ligament disruption and real syndesmotic instability.This article summarizes the available evidence in the light of the author’s opinion.Pre-operative radiographic assessment,standard radiographs,computed tomography scanning and magnetic resonance imaging are of limited value in detecting syndesmotic instability in acute ankle fractures but can be helpful in planning.Intra-operative stress testing,in the sagittal,coronal or exorotation direction,is more reliable in the diagnosis of syndesmotic instability of rotational ankle fractures.The Hook or Cotton test is more reliable than the exorotation stress test.The lateral view is more reliable than the AP mortise view because of the larger displacement in this direction.When the Hook test is used the force should be applied in the sagittal direction.A force of 100 N applied to the fibula seems to be appropriate.In the case of an unstable joint requiring syndesmotic stabilisation,the tibiofibular clear space would exceed 5 mm on the lateral stress test.When the surgeon is able to perform an ankle arthroscopy this technique is useful to detect syndesmotic injury and can guide anatomic reduction of the syndesmosis.Many guidelines formulated in this article are based on biomechanical and cadaveric studies and clinical correlation has to be established.展开更多
Ankle fracture is one of the most common lower limb fractures for they account for 9% of all fractures representing a significant portion of the trauma workload. Ankle fractures usually affect young men and older wome...Ankle fracture is one of the most common lower limb fractures for they account for 9% of all fractures representing a significant portion of the trauma workload. Ankle fractures usually affect young men and older women, however, below the age of 50;ankle fractures are the commonest in men. Two commonly used classification systems for ankle fractures include the danis weber AO classification and the Lauge-Hansen classification. There is biomechanical evidence that posterior non-locking plates are superior in stability than laterally placed plates;however there is little clinical evidence. There are several different methods of ankle fracture fixation, however the goal of treatment remains a stable anatomic reduction of talus in the ankle mortise and correction of the fibula length as a 1 mm lateral shift of the talus in the ankle mortise reduces the contact area by 42%, and displacement (or shortening) of the fibula more than 2 mm will lead to significant increases in joint contact pressures. Further research both biomechanically and clinically needs to be undertaken in order to clarify a preferable choice of fixation.展开更多
A stable and precise articulation of the distal tibiofibular syndesmosis maintains the tibiofibular relationship,and it is essential for normal motion of the ankle joint.The disruption of this joint is frequently acco...A stable and precise articulation of the distal tibiofibular syndesmosis maintains the tibiofibular relationship,and it is essential for normal motion of the ankle joint.The disruption of this joint is frequently accompanied by rotational ankle fracture,such as pronation-external rotation,and rarely occurs without ankle fracture.The diagnosis is not simple,and ideal management of the various presentations of syndesmotic injury remains controversial to this day.Anatomical restoration and stabilization of the disrupted tibiofibular syndesmosis is essential to improve functional outcomes.In such an injury,including inadequately treated,misdiagnosed and correctly diagnosed cases,a chronic pattern characterized by persistent ankle pain,function disability and early osteoarthritis can result.This paper reviews anatomical and biomechanical characteristics of this syndesmosis,the mechanism of its acute injury associated to fractures,radiological and arthroscopic diagnosis and surgical treatment.展开更多
Purpose: To measure the effectiveness of using percutaneous intramedullary screw fixation of the lateral malleolus fracture on the healing and functional outcome of ankle fracture. Materials and methods: Forty-six pat...Purpose: To measure the effectiveness of using percutaneous intramedullary screw fixation of the lateral malleolus fracture on the healing and functional outcome of ankle fracture. Materials and methods: Forty-six patients with Weber A and low Weber B displaced lateral malleolus fractures who underwent closed reduction and percutaneous internal fixation with an intramedullary, fully threaded, screw were retrospectively reviewed. A 3.5-mm, fully threaded, selftapping bone screw (stainless steel from Pelvic Set Synthes). The length of the screw varies between 100 mm and 120 mm, depending on the fracture location and pattern. Results: All fractures united within an average time to union of 8.2 weeks. In all patients the average time to full weight bearing was 6.8 weeks, whereas that in patients with isolated lateral malleolus fractures was 4.5 weeks. There were no deep wound infections or complaints of painful hardware. At latest follow-up, functional results were excellent in, 25 patients (54.3%) good in 20 (43.5%), fair in (2.2%). Conclusion: If reduction of the lateral malleolus fracture can be obtained in a closed fashion (with the aid of an image x-ray intensifier), we believe that fixation may be performed with an axial screw percutaneously. This technique is quick, safe and easy to do with less complication.展开更多
Introduction: Neglected ankle fractures are common in our regions. Patients first consult traditional healers and it is when the signs persist that they consult the surgeon for a swollen and painful ankle. Initially w...Introduction: Neglected ankle fractures are common in our regions. Patients first consult traditional healers and it is when the signs persist that they consult the surgeon for a swollen and painful ankle. Initially we always performed anatomical repairs with osteosynthesis, but the majority of patients still complained of pain and disability. We wondered whether a primary arthrodesis would not be indicated in old ankle fractures to avoid disabling pain for patients. We therefore performed a series of arthrodesis on neglected post-traumatic ankles. The objective of our study was to describe the results of arthrodesis on an old post-traumatic ankle and to propose a therapeutic indication in the face of any neglected ankle fracture. Material and Method: This was a prospective study over 8 years between December 2012 and November 2020, involving 36 cases of neglected ankle fractures treated by arthrodesis using Meary’s technique. We used AOFAS (American Orthopedic Foot and Ankle Score) preoperatively and postoperatively for an objective assessment. Results: The average follow-up was 4.2 years and our results were satisfactory (94.4%) with an average AOFAS score ranging from 27.8 preoperatively to 76.7 postoperatively. The fusion rate was 97.2%. Discussion: Arthrodesis appears here as an important alternative in the treatment of neglected ankle fractures with significant trophic disorders.展开更多
This paper describes numerical simulation of hydraulic fracturing using fracture-based continuum modeling(FBCM)of coupled geomechanical-hydrological processes to evaluate a technique for high-density fracturing and fr...This paper describes numerical simulation of hydraulic fracturing using fracture-based continuum modeling(FBCM)of coupled geomechanical-hydrological processes to evaluate a technique for high-density fracturing and fracture caging.The simulations are innovative because of modeling discrete fractures explicitly in continuum analysis.A key advantage of FBCM is that fracture initiation and propagation are modeled explicitly without changing the domain grid(i.e.no re-meshing).Further,multiple realizations of a preexisting fracture distribution can be analyzed using the same domain grid.The simulated hydraulic fracturing technique consists of pressurizing multiple wells simultaneously:initially without permeating fluids into the rock,to seed fractures uniformly and at high density in the wall rock of the wells;followed by fluid injection to propagate the seeded fracture density hydraulically.FBCM combines the ease of continuum modeling with the potential accuracy of modeling discrete fractures and fracturing explicitly.Fractures are modeled as piecewise planar based on intersections with domain elements;fracture geometry stored as continuum properties is used to calculate parameters needed to model individual fractures;and rock behavior is modeled through tensorial aggregation of the behavior of discrete fractures and unfractured rock.Simulations are presented for previously unfractured rock and for rock with preexisting fractures of horizontal,shallow-dipping,steeply dipping,or vertical orientation.Simulations of a single-well model are used to determine the pattern and spacing for a multiple-well design.The results illustrate high-density fracturing and fracture caging through simultaneous fluid injection in multiple wells:for previously unfractured rock or rock with preexisting shallow-dipping or horizontal fractures,and in situ vertical compressive stress greater than horizontal.If preexisting fractures are steeply dipping or vertical,and considering the same in situ stress condition,well pressurization without fluid permeation appears to be the only practical way to induce new fractures and contain fracturing within the target domain.展开更多
Objective To investigate the effect of computer aided 3D simulation technique for treating complicated foot and ankle fractures precisely.Methods From November 2007 to August 2009,255 patients with complicated foot an...Objective To investigate the effect of computer aided 3D simulation technique for treating complicated foot and ankle fractures precisely.Methods From November 2007 to August 2009,255 patients with complicated foot and ankle fractures展开更多
Fracture of the lateral process of the talus(FLPT)is uncommon in clinical practice and can be easily missed or misdiagnosed.In recent years,as researchers from all over the world have further deepened their research o...Fracture of the lateral process of the talus(FLPT)is uncommon in clinical practice and can be easily missed or misdiagnosed.In recent years,as researchers from all over the world have further deepened their research on FLPT,there has been a breakthrough in the classification,and the methods and principles of clinical management have changed accordingly;however,there is still no standardized guideline for the diagnosis and management of FLPT,and there have been few relevant literature review articles related to this kind of fracture in the past at least 5 years.In this article,we review the clinical classification,classification-based therapeutic recommendations,and prognosis of FLPT,with the aim of providing a reference for the clinical diagnosis and management of this infrequent fracture.展开更多
Malleolar ankle fractures have been classified using plain radiographs,and there is no consensus regarding the role of computed tomography(CT)scans in preoperative planning.We analyzed critical aspects,such as limits ...Malleolar ankle fractures have been classified using plain radiographs,and there is no consensus regarding the role of computed tomography(CT)scans in preoperative planning.We analyzed critical aspects,such as limits of standard radiographs,types of injury,classification methods and cost/benefit evaluations.CT scans allow a 3 D analysis of the fracture to be obtained and consequently assess the indication for surgical procedure,surgical access and the type of fixation devices required.This exam is useful for detecting lesions that may go unnoticed on radiographs and will help surgeons to clarify the pathoanatomy of ankle fractures.According to Arbeitsgemeinschaft fur Osteosynthesefragen/Orthopaedic Trauma Association(AO/OTA)classification,CT scan is recommended in medial malleolar fractures with vertical rim,type 44 B fractures with posterior malleolar involvement and all type 44 C fractures(according to AO/OTA).Also Tillaux-Chaput fractures(43-B1 according to AO/OTA),malleolar fractures in the presence of distal tibial fractures(43 according to AO/OTA)and distal tibia fractures in adolescents should be studied with CT scans.展开更多
The fracture toughness of rocks is a critical fracturing parameter in geo-energy exploitation playing a significant role in fracture mechanics and hydraulic fracturing.The edge-notched disk bending(ENDB)specimens are ...The fracture toughness of rocks is a critical fracturing parameter in geo-energy exploitation playing a significant role in fracture mechanics and hydraulic fracturing.The edge-notched disk bending(ENDB)specimens are employed to measure the entire range of mixed-modeⅠ/Ⅲfracture toughness of Longmaxi shale.To theoretically interpret the fracture mechanisms,this research first introduces the detailed derivations of three established fracture criteria.By distinguishing the volumetric and distortional strain energy densities,an improved three-dimensional mean strain energy density(MSED)criterion is proposed.As the critical volumetric to distortional MSED ratio decreases,the transition from tensiondominated fracture to shear-dominated fracture is observed.Our results indicate that both peak load and applied energy increase significantly with the transition from pure mode I(i.e.,tension)to pure modeⅢ(i.e.,torsion or tearing)since mode-Ⅲcracking happens in a twisted manner and mode-Ⅰcracking occurs in a coplanar manner.The macroscopic fracture signatures are consistent with those of triaxial hydraulic fracturing.The average ratio of pure mode-Ⅲfracture toughness to pure mode-Ⅰfracture toughness is 0.68,indicating that the obtained mode-Ⅲfracture resistance for a tensionbased loading system is apparent rather than true.Compared to the three mainstream fracture criteria,the present fracture criterion exhibits greater competitiveness and can successfully evaluate and predict mixed-modeⅠ/Ⅲfracture toughness of distinct materials and loading methods.展开更多
Background and Objectives: Ankle injuries are the most common type of injury in healthy active individuals. If not treated properly, recurrent sprains can lead to a condition of chronic ankle instability (CAI). The pr...Background and Objectives: Ankle injuries are the most common type of injury in healthy active individuals. If not treated properly, recurrent sprains can lead to a condition of chronic ankle instability (CAI). The present paper examines some subjects with a previous history of acute inversion ankle sprain who have developed a subsequent condition of instability, grouping them according to inclusion criteria and analyzing them through four field tests considered objective by the scientific literature: SEBT test, BEES test, TIBT test, SHT test. The data obtained were stored in order to compare them following a re-education protocol aimed at improving proprioception, balance, walking and strengthening the extrinsic and intrinsic muscles of the foot. per year. The subjects were then divided into two categories: subjects with CAI > 1 year and subjects with CAI ≤ 1 year. A protocol lasting 6 weeks was administered to both groups, trying to work on improving balance in single stance, improving static and dynamic stability, strengthening the gluteus medius and maximus (pelvis stabilizers) and strengthening of the intrinsic muscles of the foot. At the end of the protocol the subjects were all re-evaluated with the same field tests used previously and the data obtained were compared both with the pre-protocol data and with the data measured by the control subjects.展开更多
文摘BACKGROUND The recovery of limb function after ankle fracture surgery is a gradual process.The main purpose of implementing early functional exercise,joint mobility,muscle contraction function,passive ankle flexion and extension exercises,or physical factor therapy techniques is to achieve the rapid recovery of normal physiological limb function.However,currently the most effective rehabilitation training method is staged limb functional exercise,which promotes rapid recovery of limb function while preventing adverse consequences caused by overwork or insufficient training.Staged limb functional exercise divides the rehabilitation process into multiple stages,each of which has specific training objectives and contents.This method helps patients gradually restore limb function.Nevertheless,some patients still exhibit poor limb function after standardized exercise.Therefore,a functional evaluation should be performed to analyze the impact of staged functional training after ankle fracture surgery.AIM To perform a functional evaluation and determine the influencing factors of staged functional training in patients with ankle fracture.METHODS A retrospective study enrolled 150 patients who underwent surgical treatment for ankle fracture from May 2020 to May 2022 at our hospital.Univariate and multivariate linear regression analyses were performed on general data,functional exercise compliance scale for orthopedic patients,Social Support Rating Scale(SSRS),American Orthopedic Foot and Ankle Score(AOFAS)Ankle-Hindfoot Score,and pain factors[serum bradykinin(BK),prostaglandin E2(PGE2),5-hydroxytryptamine(5-HT)].RESULTS Based on the AOFAS Ankle-Hindfoot Scale,the cases were divided into the excellent function(n=111)and ordinary function(n=39)groups.Univariate analysis revealed that monthly family income,education level,diabetes mellitus,functional exercise compliance scale of orthopedic patients score,SSRS,BK,PGE2,and 5-HT significantly influenced limb function after ankle fracture(P<0.05);Multiple linear regression analysis showed that the functional exercise compliance scale score,SSRS,BK,PGE2,and 5-HT were independent risk factors affecting functional performance after staged functional exercise(P<0.05).CONCLUSION Exercise compliance,SSRS,and pain level are the independent risk factors affecting functional performance after staged functional training following ankle surgery.Clinical nursing care after ankle surgery should include analgesic and health education measures to ensure optimal recovery of limb function.
文摘Introduction and Background: Ankle injury is one of the most frequent presenting injuries to the emergency room and ankle fractures are common fracture in the lower limbs injuries that may require operative treatment with variable outcomes. Materials and Methods: Sixty-three patients were included in my retrospective study, and all with a displaced fracture of the ankle caused by high energy trauma were treated by open reduction and rigid internal fixation. Results: After follow-up at six weeks and twelve weeks, the results were satisfactory in fifty-five percent out of all the sixty-three patients. Conclusions and Recommendations: Ankle fractures occur mainly in young males of the age group between 26 and 35 years, mostly caused by fall down and motor vehicle accident.
文摘BACKGROUND Open fractures of the ankle are complex injuries requiring multidisciplinary input and are associated with significant morbidity and mortality.However,data on the clinical outcomes of open ankle fracture management in patients older than 70 is minimal.AIM To evaluate the clinical outcomes following open ankle fracture management in patients older than 70.Our secondary aim is to look at predictors of poor outcomes.METHODS Following local research and audit department registration,22 years of prospectively collated data from an electronic database in a district general hospital were assessed.All patients older than 70 years of age with an open ankle fracture requiring surgical intervention were identified.Demographic information,the nature,and the number of surgical interventions were collated.Complications,including surgical site infection(SSI),venous thromboembolic events(VTEs)during hospital stay,and mortality rate,were reviewed.RESULTS A total of 37 patients were identified(median age:84 years,range:70-98);n=30 females median age:84 years,range:70-97);n=7 males median age:74 years,range:71-98))who underwent surgical intervention after an open ankle fracture.Sixteen patients developed SSIs(43%).Superficial SSIs(n=8)were managed without surgical intervention and treated with antibiotics and regular dressing changes.Deep SSIs(n=8;20%)required a median of 3(range:2-9)surgical interventions,with four patients requiring multiple washouts and one patient having metalwork removed.VTE incidence was 5%during the hospital stay.Eight patients died within 30 d,and mortality at one year was 19%.The 10-year mortality rate was 57%.The presence of a history of stroke,cancer,or prolonged inpatient stay was found to be predictive of lower survivorship in this population(log-rank test:cancer P=0.008,stroke P=0.001,length of stay>33 d P=0.015).The presence of a cardiac history was predictive of wound complications(logistic regression,P=0.045).Age,number of operations,and diabetic history were found to be predictive of an increase in the length of stay(general linear model;age P<0.001,number of operations P<0.001,diabetes P=0.041).CONCLUSION An open ankle fracture in a patient older than 70 years has at least a 20%chance of requiring repeated surgical intervention due to deep SSIs.The presence of a cardiac history appears to be the main predictor for wound complications.
文摘Objective:To analyze the value of applying evidence-based nursing in the perioperative care of patients with ankle fractures and propose corresponding measures to improve the quality of patient care.Methods:The study started in May 2022 and was terminated in March 2023.During this period,50 patients with ankle fractures treated by our hospital were selected as research subjects.They were divided into a control group and a research group.The control group had 25 patients who received routine care,and the research group had 25 who received evidence-based care.The nursing effects of the two groups were observed and compared.Results:The pain scores,quality of life,incidence of adverse reactions,and nursing satisfaction of patients in the research group were all significantly better than those in the control group(P<0.05).Conclusion:Evidence-based nursing can effectively improve the quality of care,reduce the risk of adverse reactions,and promote patient recovery,so it is suitable for clinical implementation.
文摘BACKGROUND Locking plate fixation in osteoporotic ankle fractures may fail due to cut-out or metalwork failure.Fibula pro-tibia fixation was a technique prior to the advent of locking plates that was used to enhance stability in ankle fractures by achieving tri or tetra-cortical fixation.With locking plates,the strength of this fixation construct can be further enhanced.There is lack of evidence currently on the merits of tibiapro-fibula augmented locking plate fixation of unstable ankle fractures.AIM To assess if there is increased strength to failure,in an ankle fracture saw bone model,with a fibula pro-tibia construct when compared with standard locking plate fixation.METHODS Ten osteoporotic saw bones with simulated supination external rotation injuries were used.Five saw bones were fixed with standard locking plates whilst the other 5 saw bones were fixed with locking plates in a fibula pro-tibia construct.The fibula pro-tibia construct involved fixation with 3 consecutive locking screws applied across 3 cortices proximally from the level of the syndesmosis.All fixations were tested in axial external rotation to failure on an electromagnetic test frame(MTS 858 Mini-Bionix test machine,MTS Corp,Eden Praire,MN,United States).Torque at 30 degrees external rotation,failure torque,and external rotation angle at failure were compared between both groups and statistically analyzed.RESULTS The fibula pro-tibia construct demonstrated a statistically higher torque at 30 degrees external rotation(4.421±0.796 N/m vs 1.451±0.467 N/m;t-test P=0.000),as well as maximum torque at failure(5.079±0.694N/m vs 2.299±0.931 N/m;t-test P=0.001)compared to the standard locking plate construct.The fibula pro-tibia construct also had a lower external rotation angle at failure(54.7±14.5 vs 67.7±22.9).CONCLUSION The fibula pro-tibia locking plate construct demonstrates biomechanical superiority to standard locking plates in fixation of unstable ankle fractures in this saw bone model.There is merit in the use of this construct in patients with unstable osteoporotic ankle fractures as it may aid improved clinical outcomes.
文摘AIM: To report ankle fracture configurations and bone quality following arthroscopic-assisted reduction and internal-fixation(ARIF) or open reduction and internalfixation(ORIF). METHODS: The patients of ARIF(n = 16) or ORIF(n = 29) to treat unstable ankle fracture between 2006 and 2014 were reviewed retrospectively. Baseline data, including age, sex, type of injury, immediate postoperative fracture configuration(assessed on X-rays and graded by widest gap and largest step-off of any intraarticular site), bone quality [assessed with bone mineral density(BMD) testing] and arthritic changes on X-rays following surgical treatments were recorded for each group.RESULTS: Immediate-postoperative fracture configurations did not differ significantly between the ARIF and ORIF groups. There were anatomic alignments as 8(50%) and 8(27.6%) patients in ARIF and ORIF groups(P = 0.539) respectively. There were acceptable alignments as 12(75%) and 17(58.6%) patients in ARIF and ORIF groups(P = 0.341) respectively. The arthritic changes in follow-up period as at least 16 wk following the surgeries were shown as 6(75%) and 10(83.3%) patients in ARIF and ORIF groups(P = 0.300) respectively. Significantly more BMD tests were performed in patients aged > 60 years(P < 0.001), ARIF patients(P = 0.021), and female patients(P = 0.029). There was no significant difference in BMD test t scores between the two groups. CONCLUSION: Ankle fracture configurations following surgeries are similar between ARIF and ORIF groups, suggesting that ARIF is not superior to ORIF in treatment of unstable ankle fractures.
文摘Ankle fractures are one of the most common injuries treated by orthopaedic surgeons. A minority of patients with ankle fractures go on to develop persistent pain following anatomical reduction. These sequelae may arise as a result of untreated ligamentous or chondral injuries. This study aims to correlate acute arthroscopic ankle findings with the <i><span>Lauge-Hansen </span></i><span>fracture pattern classification. We further aim to compare subjective functional outcomes at least one year following surgery between patients who have received Open Reduction and Internal Fixation (ORIF) alone, </span><b><i><span>versus</span></i></b><i><span> </span></i><span>ORIF </span><i><span>plus</span></i><span> arthroscopy. This is a retrospective case series of patients who have undergone ankle fracture ORIF +/</span><span>-</span><span> arthroscopy from July 2014 to July 2017 inclusive. Each patient’s presenting radiograph was classified according to the </span><i><span>Lauge-Hansen</span></i><span> ankle fracture classification with subsequent correlation to intra-operative arthroscopic findings. Functional outcome at a minimum of one year was evaluated with the American Academy of Orthopaedic Surgeons (AAOS) metric. Twenty two patients underwent ankle ORIF plus arthroscopy (Group A) with a further 26 patients receiving ORIF alone (Group B). 1 in 3 supination-external-rotation type II (SER II) injuries possessed a concomitant syndesmosis injury or osteochondral lesion (OCL) on arthroscopy. 1 in 3 patients with a</span><span>n</span><span> SER IV injury had an osteochondral lesion. The mean AAOS score achieved for Group A was 89.6 (±7.9) with the mean score for Group B being 82.0 (±13.7). In conclusion, ankle arthroscopy aids the diagnosis and treatment of ligamentous and osteochondral injuries not evident on plain film with subsequent superior short-term outcomes</span><span>.</span>
文摘Treatment of fragility fractures of the distal tibia in the elderly is demanding because of osteopenic bone quality, the delicate soft tissue cuff and </span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">frequent</span></span></span></span></span><span><span><span><span><span style="font-family:""><span style="font-family:Verdana;"> crit</span><span style="font-family:Verdana;">ical circulation. We report the case of two-level tibial pseudarthroses in an</span><span style="font-family:Verdana;"> 83</span></span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">- </span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">year</span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span></span></span><span><span><span><span><span style="font-family:""><span style="font-family:Verdana;">old woman caused by multiple myeloma successfully stabilized by a long </span><span style="font-family:Verdana;">ankle arthrodesis nail combined with locking compression plate</span> <span style="font-family:Verdana;">osteosynthesis. This case is unique</span></span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> as to our best knowledge</span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> herein</span></span></span></span></span><span><span><span><span><span style="font-family:""><span style="font-family:Verdana;"> diaphyseal fractures were </span><span style="font-family:Verdana;">treated for the first time using a technique reported hitherto primarily for</span><span style="font-family:Verdana;"> fragility ankle and pilon fractures.
文摘The precise diagnosis of distal tibiofibular syndesmotic ligament injury is challenging and a distinction should be made between syndesmotic ligament disruption and real syndesmotic instability.This article summarizes the available evidence in the light of the author’s opinion.Pre-operative radiographic assessment,standard radiographs,computed tomography scanning and magnetic resonance imaging are of limited value in detecting syndesmotic instability in acute ankle fractures but can be helpful in planning.Intra-operative stress testing,in the sagittal,coronal or exorotation direction,is more reliable in the diagnosis of syndesmotic instability of rotational ankle fractures.The Hook or Cotton test is more reliable than the exorotation stress test.The lateral view is more reliable than the AP mortise view because of the larger displacement in this direction.When the Hook test is used the force should be applied in the sagittal direction.A force of 100 N applied to the fibula seems to be appropriate.In the case of an unstable joint requiring syndesmotic stabilisation,the tibiofibular clear space would exceed 5 mm on the lateral stress test.When the surgeon is able to perform an ankle arthroscopy this technique is useful to detect syndesmotic injury and can guide anatomic reduction of the syndesmosis.Many guidelines formulated in this article are based on biomechanical and cadaveric studies and clinical correlation has to be established.
文摘Ankle fracture is one of the most common lower limb fractures for they account for 9% of all fractures representing a significant portion of the trauma workload. Ankle fractures usually affect young men and older women, however, below the age of 50;ankle fractures are the commonest in men. Two commonly used classification systems for ankle fractures include the danis weber AO classification and the Lauge-Hansen classification. There is biomechanical evidence that posterior non-locking plates are superior in stability than laterally placed plates;however there is little clinical evidence. There are several different methods of ankle fracture fixation, however the goal of treatment remains a stable anatomic reduction of talus in the ankle mortise and correction of the fibula length as a 1 mm lateral shift of the talus in the ankle mortise reduces the contact area by 42%, and displacement (or shortening) of the fibula more than 2 mm will lead to significant increases in joint contact pressures. Further research both biomechanically and clinically needs to be undertaken in order to clarify a preferable choice of fixation.
文摘A stable and precise articulation of the distal tibiofibular syndesmosis maintains the tibiofibular relationship,and it is essential for normal motion of the ankle joint.The disruption of this joint is frequently accompanied by rotational ankle fracture,such as pronation-external rotation,and rarely occurs without ankle fracture.The diagnosis is not simple,and ideal management of the various presentations of syndesmotic injury remains controversial to this day.Anatomical restoration and stabilization of the disrupted tibiofibular syndesmosis is essential to improve functional outcomes.In such an injury,including inadequately treated,misdiagnosed and correctly diagnosed cases,a chronic pattern characterized by persistent ankle pain,function disability and early osteoarthritis can result.This paper reviews anatomical and biomechanical characteristics of this syndesmosis,the mechanism of its acute injury associated to fractures,radiological and arthroscopic diagnosis and surgical treatment.
文摘Purpose: To measure the effectiveness of using percutaneous intramedullary screw fixation of the lateral malleolus fracture on the healing and functional outcome of ankle fracture. Materials and methods: Forty-six patients with Weber A and low Weber B displaced lateral malleolus fractures who underwent closed reduction and percutaneous internal fixation with an intramedullary, fully threaded, screw were retrospectively reviewed. A 3.5-mm, fully threaded, selftapping bone screw (stainless steel from Pelvic Set Synthes). The length of the screw varies between 100 mm and 120 mm, depending on the fracture location and pattern. Results: All fractures united within an average time to union of 8.2 weeks. In all patients the average time to full weight bearing was 6.8 weeks, whereas that in patients with isolated lateral malleolus fractures was 4.5 weeks. There were no deep wound infections or complaints of painful hardware. At latest follow-up, functional results were excellent in, 25 patients (54.3%) good in 20 (43.5%), fair in (2.2%). Conclusion: If reduction of the lateral malleolus fracture can be obtained in a closed fashion (with the aid of an image x-ray intensifier), we believe that fixation may be performed with an axial screw percutaneously. This technique is quick, safe and easy to do with less complication.
文摘Introduction: Neglected ankle fractures are common in our regions. Patients first consult traditional healers and it is when the signs persist that they consult the surgeon for a swollen and painful ankle. Initially we always performed anatomical repairs with osteosynthesis, but the majority of patients still complained of pain and disability. We wondered whether a primary arthrodesis would not be indicated in old ankle fractures to avoid disabling pain for patients. We therefore performed a series of arthrodesis on neglected post-traumatic ankles. The objective of our study was to describe the results of arthrodesis on an old post-traumatic ankle and to propose a therapeutic indication in the face of any neglected ankle fracture. Material and Method: This was a prospective study over 8 years between December 2012 and November 2020, involving 36 cases of neglected ankle fractures treated by arthrodesis using Meary’s technique. We used AOFAS (American Orthopedic Foot and Ankle Score) preoperatively and postoperatively for an objective assessment. Results: The average follow-up was 4.2 years and our results were satisfactory (94.4%) with an average AOFAS score ranging from 27.8 preoperatively to 76.7 postoperatively. The fusion rate was 97.2%. Discussion: Arthrodesis appears here as an important alternative in the treatment of neglected ankle fractures with significant trophic disorders.
文摘This paper describes numerical simulation of hydraulic fracturing using fracture-based continuum modeling(FBCM)of coupled geomechanical-hydrological processes to evaluate a technique for high-density fracturing and fracture caging.The simulations are innovative because of modeling discrete fractures explicitly in continuum analysis.A key advantage of FBCM is that fracture initiation and propagation are modeled explicitly without changing the domain grid(i.e.no re-meshing).Further,multiple realizations of a preexisting fracture distribution can be analyzed using the same domain grid.The simulated hydraulic fracturing technique consists of pressurizing multiple wells simultaneously:initially without permeating fluids into the rock,to seed fractures uniformly and at high density in the wall rock of the wells;followed by fluid injection to propagate the seeded fracture density hydraulically.FBCM combines the ease of continuum modeling with the potential accuracy of modeling discrete fractures and fracturing explicitly.Fractures are modeled as piecewise planar based on intersections with domain elements;fracture geometry stored as continuum properties is used to calculate parameters needed to model individual fractures;and rock behavior is modeled through tensorial aggregation of the behavior of discrete fractures and unfractured rock.Simulations are presented for previously unfractured rock and for rock with preexisting fractures of horizontal,shallow-dipping,steeply dipping,or vertical orientation.Simulations of a single-well model are used to determine the pattern and spacing for a multiple-well design.The results illustrate high-density fracturing and fracture caging through simultaneous fluid injection in multiple wells:for previously unfractured rock or rock with preexisting shallow-dipping or horizontal fractures,and in situ vertical compressive stress greater than horizontal.If preexisting fractures are steeply dipping or vertical,and considering the same in situ stress condition,well pressurization without fluid permeation appears to be the only practical way to induce new fractures and contain fracturing within the target domain.
文摘Objective To investigate the effect of computer aided 3D simulation technique for treating complicated foot and ankle fractures precisely.Methods From November 2007 to August 2009,255 patients with complicated foot and ankle fractures
基金Supported by The China Scholarship Council,No.202308420035.
文摘Fracture of the lateral process of the talus(FLPT)is uncommon in clinical practice and can be easily missed or misdiagnosed.In recent years,as researchers from all over the world have further deepened their research on FLPT,there has been a breakthrough in the classification,and the methods and principles of clinical management have changed accordingly;however,there is still no standardized guideline for the diagnosis and management of FLPT,and there have been few relevant literature review articles related to this kind of fracture in the past at least 5 years.In this article,we review the clinical classification,classification-based therapeutic recommendations,and prognosis of FLPT,with the aim of providing a reference for the clinical diagnosis and management of this infrequent fracture.
文摘Malleolar ankle fractures have been classified using plain radiographs,and there is no consensus regarding the role of computed tomography(CT)scans in preoperative planning.We analyzed critical aspects,such as limits of standard radiographs,types of injury,classification methods and cost/benefit evaluations.CT scans allow a 3 D analysis of the fracture to be obtained and consequently assess the indication for surgical procedure,surgical access and the type of fixation devices required.This exam is useful for detecting lesions that may go unnoticed on radiographs and will help surgeons to clarify the pathoanatomy of ankle fractures.According to Arbeitsgemeinschaft fur Osteosynthesefragen/Orthopaedic Trauma Association(AO/OTA)classification,CT scan is recommended in medial malleolar fractures with vertical rim,type 44 B fractures with posterior malleolar involvement and all type 44 C fractures(according to AO/OTA).Also Tillaux-Chaput fractures(43-B1 according to AO/OTA),malleolar fractures in the presence of distal tibial fractures(43 according to AO/OTA)and distal tibia fractures in adolescents should be studied with CT scans.
基金supported by National Natural Science Foundation of China(Grant Nos.52364004,52264006,and 52164001).
文摘The fracture toughness of rocks is a critical fracturing parameter in geo-energy exploitation playing a significant role in fracture mechanics and hydraulic fracturing.The edge-notched disk bending(ENDB)specimens are employed to measure the entire range of mixed-modeⅠ/Ⅲfracture toughness of Longmaxi shale.To theoretically interpret the fracture mechanisms,this research first introduces the detailed derivations of three established fracture criteria.By distinguishing the volumetric and distortional strain energy densities,an improved three-dimensional mean strain energy density(MSED)criterion is proposed.As the critical volumetric to distortional MSED ratio decreases,the transition from tensiondominated fracture to shear-dominated fracture is observed.Our results indicate that both peak load and applied energy increase significantly with the transition from pure mode I(i.e.,tension)to pure modeⅢ(i.e.,torsion or tearing)since mode-Ⅲcracking happens in a twisted manner and mode-Ⅰcracking occurs in a coplanar manner.The macroscopic fracture signatures are consistent with those of triaxial hydraulic fracturing.The average ratio of pure mode-Ⅲfracture toughness to pure mode-Ⅰfracture toughness is 0.68,indicating that the obtained mode-Ⅲfracture resistance for a tensionbased loading system is apparent rather than true.Compared to the three mainstream fracture criteria,the present fracture criterion exhibits greater competitiveness and can successfully evaluate and predict mixed-modeⅠ/Ⅲfracture toughness of distinct materials and loading methods.
文摘Background and Objectives: Ankle injuries are the most common type of injury in healthy active individuals. If not treated properly, recurrent sprains can lead to a condition of chronic ankle instability (CAI). The present paper examines some subjects with a previous history of acute inversion ankle sprain who have developed a subsequent condition of instability, grouping them according to inclusion criteria and analyzing them through four field tests considered objective by the scientific literature: SEBT test, BEES test, TIBT test, SHT test. The data obtained were stored in order to compare them following a re-education protocol aimed at improving proprioception, balance, walking and strengthening the extrinsic and intrinsic muscles of the foot. per year. The subjects were then divided into two categories: subjects with CAI > 1 year and subjects with CAI ≤ 1 year. A protocol lasting 6 weeks was administered to both groups, trying to work on improving balance in single stance, improving static and dynamic stability, strengthening the gluteus medius and maximus (pelvis stabilizers) and strengthening of the intrinsic muscles of the foot. At the end of the protocol the subjects were all re-evaluated with the same field tests used previously and the data obtained were compared both with the pre-protocol data and with the data measured by the control subjects.