2012年 · 第15卷第06期

Abstract：Objective:To explore the changes of Treg-Th17 balance influenced by corticosterone,major effect hormone of hypothalamic-pituitary-adrenal (HPA) axis under running stress.Methods:A total of 25 corticotropin-releasing hormone (CRH) wildtype (CRH+/+) and knockout (CRH-/-) mice were adopt and divided into 4 groups as follows:CRH+/+ ctrl,CRH+/+ stress,CRH-/-ctrl and CRH-/-stress.All mice in stress groups were under 2 h running.After 1 h,blood plasma in all groups was collected and the expression of corticosterone and IL-17A was detected by ELISA.Meanwhile,unicell suspensions of peripheral lymph node and spleen in each group were prepared too and stained by PE-CD4 and FITC-CD25,then the changes ofTreg (CD4+CD25+) in different groups were checked by flow cytometry; all data were statistically analyzed by the software of WinMDI 2.9,SPSS 11.5,Origin 7.5 and Matlab 2-D and 3-D plot function.Results:The levels of corticosterone were significantly higher in stress groups than that in corresponding control groups (P＜0.05),especially in CRH+/+ stress group (P＜0.01).However,the changes of Tregs were not obvious between stress groups and control groups with respective genotypes (P＜0.05).Compared with that in CRH+/+ control group,the ratio of Treg and the expression of IL-17A in CRH-/-stress group were significantly higher than those in control group (P＜0.05).Combined with the expression levels of corticosterone,Treg and Th17,our study suggests that endogenous glucocorticoid with basal level may cause the changes in Treg-Th17 balance.Moreover,as the corticosterone level increases,the expression of Treg and Th17 appears to manifest antagonistic fluctuant status with a rising tendency in general.Conclusion:Endogenous glucocorticoid under early stage of stress may increase the function of T lymphocyte immunity to some extent。

Abstract：Objective:To investigate the stability and three-dimensional movements of the atlantoaxial joint after artificial atlanto-odontoid joint (AAOJ) arthroplasty by comparing with a conventional method.Methods:After anterior decompression,24 human cadaveric spinal specimens of C0-C3 were randomly divided into two groups:Group A receiving artificial AAOJ arthroplasty;Group B experiencing anterior transarticular screw (ATAS) fixation.Two groups underwent flexibility test in intact and instrumented states.Rotational angle of the C0-C3 segments was measured to study the immediate stability and function of anterior decompression with AAOJ arthroplasty compared with the intact state and ATAS fixation.Results:Compared with the intact state,anterior decompression with AAOJ arthroplasty resulted in a significant decrease in the range of motion (ROM) and neutral zone (NZ) during flexion,extension and lateral bending (P＜0.05); however,with regard to axial rotation,there was no significant difference in ROM and NZ (P＞0.05).Compared with anterior decompression with ATAS fixation,anterior decompression with AAOJ arthroplasty during flexion,extension and lateral bending,significant difference was found in ROM and NZ (P＞0.05); however,as for axial rotation,there was a significant increase in ROM and NZ (P＜0.05).Conclusion:The self-designed AAOJ has an excellent biomechanical performance,which can restore excellent instant stability and preserve the movement of the atlantoaxial joint。

Abstract：Objective:By studying the mode and morphologic character of high fall injuries on the scene,and exploring the injury situation of different heights,different fall ways and postures,to provide a reference for the forensic identification of high fall injury.Methods:All the high fall cases were statistically analysed according to their gender,age,ground-touching posture,fall height,site and type of the injury.Results:Among 134 high fall cases,98 were male and 36 were female with the age ranging from 2-71 years (37.6±16.9 on average),in which,10-60 years old group consisted of 110 cases (82％).Most cases fell from windows or roofs (73％) and the touching objects were cement ground or shaft bottom of elevators.Among these cases,head injury was generally serious,followed by chest and abdominal injuries.The morphologic changes depend upon the height,nature,as well as the posture at the point while the body touches the ground.Conclusion:Morphologic study of high fall injury assists medicolegal physicians to make correct identifications of the cause and nature of high fall injuries。

Abstract：Objective:To investigate the expression of Caspase-3 and Hsp70 in rabbits after severe traumatic brain injury (TBI) and to explore the feasibility of its application in estimation of injury time in forensic medicine.Methods:A rabbit model of heavy TBI was developed by high velocity impact on the parietal bone with an iron stick.Totally 8 healthy adult New Zealand white rabbits were randomly divided into control group (n=2) and injury group (n=6).Four hours after injury,tissue specimens from the parietal lobe,temporal lobe,occipital lobe,cerebellum and brainstem were harvested to detect the expression of Hsp70 and Caspase-3 by immunohistochemistry.Besides,the gray values of cells positive for Hsp70 and Caspase-3 were analyzed with an image analyzer.Results:Immunohistochemistry staining demonstrated a low level of Caspase-3 and Hsp70 expression in normal control group.While in injury group,both the Caspase-3and Hsp70 expression was significantly elevated (P＜0.05).Positive cells gathered around the lesion focus.Occipital lobe and cerebellum had fewer positive cells while temporal and brainstem had the fewest.Conclusion:The expression of Caspase-3 and Hsp70 at an early stage following severe TBI is characteristic and can be applied to estimate the time of injury。

Abstract：Objective:To study the patterns and morphologic characteristics of blunt head injury and analyse its formative mechanism in attempt to provide references for medicolegal expertise.Methods:The statistical analysis was done in terms of gender,age,as well as the nature,pattern,location,and feature of the injuries.Results:Among the 202 cases of head injury-induced death,124 were male and 78 female with the age ranging from 1-81 years.Death caused by homicide was dominant (106,52.5％),followed by suicide (49,24.3％) and accident (44,21.8％).The majority of suicide-induced death were by falling from height,and traffic crash was responsible for majority of unexpected death cases.The morphology and pathogenesis of the injuries varied according to differences on the mode,magnitude,and orientation of the outside force giving rise to blunt injury as well as the character of vulnerants.Conclusion:Studies on the morphology and its formative rationale of blunt head injury will offer easy access to medicolegal expertise on the mode and character of the injury。

Abstract：Objective:To introduce a new animal model of graded mechanical primary brainstem injury (BSI).Methods:Altogether 45 rabbits were subjected to BSI by type Ⅱ biological impact machine designed by the Third Military Medical University.The animals were divided into 4 experimental groups (n=10) and 1 control group (n=5) according to different magnitudes of impact pressure imposed on the occipital nodule:Group 1,500-520 kPa; Group 2,520-540 kPa; Group 3,540-560 kPa; Group 4,560-580 kPa and Group 5,0 kPa with 20 kPa increase in each grade.The impact depth was a constant 0.5 cm.After injury,the clinical symptoms and signs as well as pathological changes were observed.Results:Rabbits in Group 1 revealed mild physiological reaction of BSI.They had localized cerebral contusion with punctate hemorrhage and subarachnoid hemorrhage (SAH) was limited to the peripheral tissues at the impact area.In Group 2,obvious physiological reaction was observed.Local pathological lesions reached the superficial layer ofbrainstem tissues; focal hemorrhage and girdleshaped SAH in basilar pon were observed under microscope.In Group 3,BSI was more severe with a long respiratory depression.Pathological lesions reached the inner portion of brainstem with massive hemorrhage and the whole brainstem was wrapped by subarachnoid hematoma.In Group 4,most rabbits died due to severe BSI.Pathological lesions deepened to the central brainstem with wide pathological change,rapture of the medulla oblongata central canal.Group 5 was the control group,with normal brainstem structure and no lesion observed.Conclusion:This model successfully simulates different levels ofbrainstem mechanical injury and clearly shows the subsequent pathological changes following injury.It takes two external parameters (impact pressure and depth) and has a similar injury mechanism to clinical accelerating BSI.Moreover it is reproducible and stable,thus being beneficial for exploring pathophysiological mechanism,diagnosis and forensic identification of various degrees of BSI。

Abstract：Objective:To report the technique of reconstruction of large skin and soft tissue defects in the upper extremity using pedicled latissimus dorsi myocutaneous flaps.Methods:Six patients with large skin and soft tissue defects were included in this report.There were 5 trauma patients and the rest one needed to receive plastic surgery for his extremity scar.All wounds were in the upper extremity.The sizes of defects ranged from 15 cm×6 cm to 30 cm× 18 cm.Pedicled latissimus dorsi myocutaneous flaps were designed according to the defect area and raised with part of latissimus dorsi.The thoracodorsal artery and its perforators were carefully protected during surgery.Results:All flaps healed primarily without flap congestion,margin necrosis or infection.The skin donor sites either received split-thickness skin graft (3 cases,mostly from the anterior thigh) or was closed primarily (3 cases)and had minimal morbidity.Follow-up of 6-12 months showed that the contour of flap was aesthetic and the function of limb was excellent.Conclusion:Our experience indicates that the pedicled latissimus dorsi myocutaneous flap is favorable for reconstruction of large skin and soft tissue defects in the upper extremity。

Abstract：Harms technique of C1-C2 fixation for atlantoaxial complex becomes more popular due to good fusion rate and low vertebral artery injury (VAI) rate.But considering the unique and variable anatomy of atlantoaxial complex,iatrogenic VAI will result in catastrophic consequences and provides particular surgical challenges for surgeons.To our knowledge,comparing with iatrogenic VAI in the screw hole,iatrogenic VAI in the "open space" is much rarer during the Harms technique of C1-C2 fixation.In this article,we present a case of iatrogenic vertebral artery pseudoaneurysm after Harms technique of posterior C1-C2 fixation.This case of iatrogenic VAI effectively treated by endovascular coil occlusion and external local compression was initially misdiagnosed as VAI by pedicle screw perforation.It can be concluded that intraoperative or postoperative computed angiography is very helpful to diagnose the exact site of VAI and the combination of endovascular coil occlusion as well as external local compression can further prevent bleeding and abnormal vertebral artery flow in the pseudoaneurysm.However,patients treated require further follow-up to confirm that there is no recurrence of the pseudoaneurysm。

Abstract：High-velocity penetrating pelvic injury is one of the most difficult challenges to trauma surgeons.The injury sites frequently include soft tissue,pelvis,genitourinary tract,vascular structures and intraabdominal viscera.We present an unusual case of a male patient suffering a collision at night with a deformed steel bar penetrating into his right groin.Careful planning of the surgical approach is important before extracting the foreign body.The possibility of multiorgan damage to intrapelvic structures such as colon,urinary bladder,vessels and nerves,frequently necessitates a multidisciplinary involvement and systematic approach.Besides,limited incision as well as modification should be considered,and debridement and perioperative antibiotics can be used to reduce the risk of serious wound infection。

Abstract：Solitary coronal shear fractures of femoral condyle,such as Hoffa's fracture,are usually associated with supracondylar or intercondylar fractures of the femur.These fractures are rare and seen in the context of high energy mechanism leading to multiple injuries; therefore a thorough workup of the patient is required to rule out other significant injuries.Hoffa's fracture associated with femoral shaft and proximal tibial fractures is extremely rare and no such injury has been reported previously.We report two such cases which were managed with standard operative fixation techniques and demonstrated good to excellent functional outcome after a follow-up of one year.This report emphasizes that high index of suspicion is required for diagnosis of these injuries and a thorough workup is mandatory to rule out other associated injuries.We also propose a possible mechanism of injury。

Abstract：Total hip arthroplasty (THA) for an untreated acetabular fracture is technically challenging and the long-term result is not so favorable.A 45-year-old female patient with untreated column and comminuted posterior wall fracture of the acetabulum was treated in our institution by reconstruction of the posterior wall using iliac strut autograft and plate stabilization of the posterior column with cancellous grafting and cementless THA in a single stage.At 3 years' follow-up,the patient was independently mobile without limb length discrepancy.Radiological evaluation showed well integrated components and bone grafts.No evidence of aseptic loosening or osteolysis was found.This report aims to emphasize that bony acetabular reconstruction allows the use of primary hip components,which improves prosthesis longevity and preserves bone stock for a future revision。

Abstract：A 48-year-old man sustained a traffic accident injury to his left leg.It was an open fracture of the left tibia and fibula accompanied by a large soft tissue defect (27 cm×7 cm).Doppler examination revealed the posterior tibial artery was occluded due to thrombosis.Three weeks after injury,the latissimus dors myocutaneous flap was elevated with a T-shaped vascular pedicle and was interposed between the two vascular ends of the posterior tibial vessel of the contralateral leg.Two end to end anastomoses were performed between the two vascular ends of the posterior tibial vessel of the contralateral leg and the latissimus dors myocutaneous flap's T-shaped vascular pedicle.The latissimus dorsi myocutaneous flap was used for repair of a large soft tissue defect of the left leg.The vascular pedicle was cut offafter 28 days and the flap survived completely.After 3-years' follow-up postoperatively,a good contour was confirmed at the recipient area.The right tibia and fibula fractures were confirmed healing radiologically.The posterior tibial artery of contralateral leg was demonstrated patent by clinical and Doppler examinations。

Abstract：Posterior shoulder dislocation is a rare event that may occur after a direct trauma,an epileptic seizure,electric shock or electroconvulsive therapy.In more than 50％ of the cases,posterior dislocations are missed on initial evaluation and often misdiagnosed as frozen shoulders with unfortunate consequences.We present the case of a missed posterior subluxation and reverse Hill Sachs lesion (McLaughlin lesion) in a 40-year-old woman caused by anelectric shock of 240 V.The patient underwent surgery in our institute two weeks after the injury.The humeral head was reduced and the reverse Hill Sachs lesion was filled by demineralized bone matrix allograft with osteoinductive factors.Tendons were repaired and a temporaneous artrodesis was performed.At the final follow up of 12 months,we obtained a Costant Score of 93 and the patient returned to her previous daily activities。

Abstract：When compared to adults,pediatric fractures unite readily and nonunion is quite rare.Nonunion is often associated with open fractures,operative interventions,infection,pediatric osteogenesis imperfecta and neurofibromatosis.There are only a few studies and reports mentioning nonunion following conservative management of closed pediatric fractures.We report here a case of an eighteen-month-old child who developed nonunion following treatment of fracture of both forearm bones with cast and was successfully treated with plating.To the best of our knowledge,this is the youngest reported case of nonunion following conservative management of closed diaphyseal pediatric fracture。

Abstract：Traumatic posterior hip dislocation is an uncommon injury in children,constituting less than 5％ of paediatric dislocations.In a younger child (＜5 years),minor trauma such as a slip or fall from a low height may cause a hip dislocation,whereas in an adolescent a dislocation is usually caused by a major trauma such as motor vehicle accident.In this case report we present a rare case of traumatic hip dislocation in a 16-month-old girl.Early detection and closed reduction ensured good outcome in our case.A high index of suspicion is necessary to achieve satisfactory reduction within six hours of dislocation because reduction after this period will greatly increase the risk of complications。

Abstract：Simultaneous bilateral intertrochanteric fractures are very rare.There is a paucity of data in current literature documenting patients with such kind of hip fractures.It is severe and potentially life-threatening,associated with a high morbidity.The major determinants of successful outcome are high vigilance,early single stage stabilization and mobilization as well as management of associated comorbid conditions that may influence the long term rehabilitation of patients.Here we reported 4 cases of concurrent bilateral trochanteric fractures along with review of the literature.Our study aimed to discover its frequency,identify the injury mechanisms as well as factors present in the pathogenesis of these fractures,and outline the available treatment modalities。