2012年 · 第15卷第02期

Abstract：Objective: To establish an animal model to replicate the blunt impact brain injury in forensic medicine.Methods:Twenty-four New Zealand white rabbits were randomly divided into control group (n=4),minor injury group (n=10) and severe injury group (n=10).Based on the BIM- Ⅱ Horizontal Bio-impact Machine,self-designed iron bar was used to produce blunt brain injury.Two rabbits from each injury group were randomly selected to monitor the change ofintracranial pressure (ICP) during the impacting process by pressure microsensors.Six hours after injury,all the rabbits were dissected to observe the injury morphology and underwent routine pathological examination.Results: Varying degrees of nervous system positive signs were observed in all the injured rabbits.Within 6 hours,the mortality rate was 1/10 in the minor injury group and 6/10 in the severe injury group.Morphological changes consisted of different levels of scalp hematoma,skull fracture,epiduraI hematoma,subdural hematoma,subarachnoid hemorrhage and brain injury.At the moment of hitting,the ICP was greater in severe injury group than in mild injury group; and within the same group,the impact side showed positive pressure while the opposite side showed negative pressure.Conclusions:Under the rigidly-controlled experimental condition,this animal model has a good reproducibility and stable results.Meanwhile,it is able to simulate the morphology of iron strike-induced injury,thus can be used to study the mechanism of blunt head injury in forensic medicine。

Abstract：Increase of microvascular permeability is one of the most important pathological events in the pathogenesis of trauma and bum injury.Massive leakage of fluid from vascular space leads to lose of blood plasma and decrease of effective circulatory blood volume,resulting in formation of severe tissue edema,hypotension or even shock,especially in severe bum injury.Fluid resuscitation has been the only valid approach to sustain patient's blood volume for a long time,due to the lack of overall and profound understanding of the mechanisms of vascular hyperpenneability response.There is an emerging concept in recent years that some so-called barrier stabilizing mediators play a positive role in preventing the increase of vascular permeability.These mediators may be released in response to proinflammatory mediators and serve to restore endothelial barrier function.Some of these stabilizing mediators are important even in quiescent state because they preserve basal vascular permeability at low levels.This review introduces some of these mediators and reveals their underlying signaling mechanisms during endothelial barrier enhancing process。

Abstract：With the increase of elderly population,more and more implant operations need to be performed in osteoporotic bone,while different forms of microdamage will be produced in peri-implant bone intraoperatively,including high- and low-density diffuse damages,as well as linear cracks.The length and location of the microcracks are the main factors in affecting the biomechanical performance of bone.Suppression of bone remodeling by bisphosphonates may lead to microdamage accumulation,which is often accompanied with the decrease of bone strength and the increase of bone fragility.Microdamage can be repaired by bone remodeling or mineralization to maintain the strength and structural integrity.Both remodeling and mineralization can affect the bone quality and long-term implant stability.In this paper,we make a brief summary of some important issues and research progresses in this field。

Abstract：Horseshoe kidney is an uncommon anomaly of the urinary system with an increased risk of injury during penetrating and blunt abdominal traumas.Selfinflicted abdominal stab wound,a rare type of abdominal injury,accounts for only a small percentage of suicidal attempts and may be infrequently encountered by physicians in trauma centers.Psychiatric disorders and alcohol or drug abuse are common risk factors in cases of self-stabbing.Here we report a rare case of self-stabbing of a horseshoe kidney.The case was a 19-year-old man with self-inflicted abdominal stab wound who was referred to our department of radiology due to re-occurred gross hematuria three days after exploratory laparotomy and surgical repair of injured abdominal organs.A horseshoe kidney was incidentally found in the patient's abdominal computed tomography.Renal angiography revealed active contrast extravasation from one of the segmental arteries.Selective transarterial embolization with a coil was successfully performed to control the hematuria。

Abstract：Inferior dislocation of the hip is the rarest type in hip dislocation.Very few cases have been reported in the anglophonic literature,most of which involved the pediatric age group.Surprisingly,we came across a 30-year-old patient with a bilateral inferior hip dislocation.He had sustained a road traffic accident and the attitude of both hip joints was flexion and abduction.The diagnosis was confirmed by radiographs which revealed the long axis of the femur at an angle of 110 (fight) degrees and 100 (left) degrees respectively away from the axis.Closed reduction under sedation was successfully performed.Skin traction for a period of 6 weeks was advised and the follow-up revealed an excellent result.We present the details of this case,the first of its kind along with a review of the literature,discussing the various modes and mechanisms of injury inducing inferior dislocation of the hip。

Abstract：The larvae of musca domestica were put in use to discard the dead tissue of a case of severe burn.A total of 50 000 aseptic maggots were put onto the infective wound surface,and aseptic dressings overlaid the surface.Three days later,another 20 000 maggots were put onto the wound for the second therapy.After twice maggot debridement,most necrotic muscle tissues of the wound were cleaned up,and eventually fresh granulation tissue grew and later the wound was covered and healed by 3 times of skin grafting.The result demonstrates that maggot therapy is safe and effective with no adverse complications except pain。

Abstract：Thorn prick injuries are generally conceded frivolous and rarely demand medical attention.Howbeit deep seated injuries are well described in the literature.We presented a case of thorn prick injury to the knee that manifested as Brodie's abscess of the medial distal femoral condyle and synovitis.Magnetic resonance imaging (MRI)and ultrasonography could only construe the affliction but not spot the thorn.Arthrotomy was undertaken for exploration and debridement.Empirical therapy with initial systemic Cefotaxime and subsequent Ofloxacin worked well after the surgery.Deep seated injuries by a thorn prick may take a protracted and torpid course.Thorough curettage of the bony lesion and debridement are vital for proper management。

Abstract：Objective: To investigate the material properties of normal and degenerated intervertebral discs (IVDs) and examine the effect of degenerative changes on IVD pathology.Methods: A computer-based online search was undertaken to identify English articles about material properties of IVDs published from January 1950 to 2011 in PubMed database.The retrieved keywords included material properties,intervertebral disc and degeneration.Based on the principles of reliability,advancement and efficiency,the obtained data were primarily examined,and the original source was retrieved to read the full-text.Repetitive articles were excluded.The data of material properties of normal and degenerated IVDs were summarized and analyzed by meta-analysis.Results: The data of Young's modulus,Poisson's ratio,shear modulus,hydraulic permeability and intradiscal pressure of normal and degenerated IVDs were obtained.Compared with normal IVDs,the Young's modulus and shear modulus of annulus fibrosus and nucleus pulposus were higher in degenerated IVDs,the Poisson's ratio was lower while the hydraulic permeability and intradiscal pressure were higher.Besides,the degeneration-related alterations in IVDs had an influence both on itself and other spinal structures,leading to diseases such as bulging disc,discogenic pain and spinal stenosis.Meanwhile,the heavy mechanical loading and injury indicated important pathways to IVD degeneration.Conclusions: To a certain extent,the degenerative changes of IVD influence its material properties.And the degeneration-related alterations of composition can cause structural failure of IVDs,leading to injuries and diseases。

Abstract：Objective: To investigate the relationship between eye injury and laser in-situ keratomileusis (LASIK) surgery in military personnel.Methods: This retrospective study collected the data from 27 evacuation hospitals of Chinese army.All medical records of eye injuries in military personnel admitted to the 27 hospitals between January 2006 and December 2010 were reviewed.Patients' detailed information was analyzed,including the injury time,place,type,cause,as well as examination,treatment and outcome.Results: There were 72 eye-injured patients who had been treated by LASIK before.The incidence was rising year by year.Among them,69 patients were diagnosed with mechanical ocular injury and 3 with non-mechanical ocular injury; 29 patients had traumatic flap-related complications and 21 patients need surgery.There was statistical difference when compared with those having no refractive surgery history.Visual acuity recovered well at discharge.Conclusion: There is a high risk of potential traumatic flap problems after LASIK and it is not recommended in army service。

Abstract：Objective: To study the effect of internal fixation performed at different times on therapeutic outcomes of Schatzker Ⅳ-Ⅵ tibial plateau fractures.Methods:The clinical data of 42 cases ofSchatzker Ⅳ- Ⅵ tibial plateau fractures treated in our department were analyzed retrospectively.Among these 42 patients,21 received surgical treatment within 12 h after injury (Group Ⅰ),the other 21 were first treated by traction or plaster fixation followed by a delayed internal fixation after soft tissue swelling subsided (Group Ⅱ).The surgical time,complications,length of hospital stay,cost of hospitalization,and time for fracture union,as well as functional recovery were analyzed and compared between the two groups.Results: After 10-28 months follow-up (mean 16.5 months),except 5 cases who lost to follow-up,no differences were found between the two groups regarding surgical time,preoperative and postoperative complications,healing time or the Hospital for Special Surgery (HSS) score at the end of follow-up,but significant differences were found in the length of hospital stay,cost of hospitalization and HSS score at 3 months after operation (P＜0.05).Conclusion: Under certain conditions,early intemal fixation for Schatzker Ⅳ-Ⅵ tibial plateau fracture is feasible,which can shorten the length of hospital stay,decrease the cost of hospitalization and promote early functional rehabilitation。