Emerging role of physiotherapy in management of crush injury over forearm

The objective of the case report is to discuss the case of a patient with crush injury over right forearm. A 37 years old male came with complain of pain, swelling, restricted range over affected side, muscle weakness over right forearm, wrist and hand, reduced grip strength on right hand, and difficulties in ADL扴 over right-handfollowing crush injury over right forearm. Treatment involved physical therapy and Electro modalities for the elimination of pain and returning the patient抯 full range of motion in the wrist and hand. After range of motion was restored, a home exercise program was initiated. The home exercise program included a return to ADLs and occupational related activity and active, resistive, gripping activities of the hand. After 11/2 month follow up, our patient showed dramatic recovery after appropriate Surgical and physiotherapy management. Physiotherapy plays significant role in the elimination of pain, improving range; muscle strength and hand function and also reduces the risk of stiffness, contracture and deformity in crush injuries.

Experimental study on the correlation between microcirculation and contrast-enhanced ultrasonography after crush injury of limbs / 中华超声影像学杂志

Objective:To explore the microcirculation formation mechanism of contrast-enhanced ultrasonography imaging performance in rabbits with limb muscle crush injury.Methods:Seventy-two New Zealand white rabbits were randomly divided into two groups. A limb muscle crush injury model was created by airing a balloon cuff device with a force of 40 kPa. Contrast-enhanced ultrasonography parameters were detected in the first group.In vivo microcirculation parameters were detected in the second group. Fine blood vessel diameter and blood flow velocity were calculated before extrusion and 0.5 h, 2 h, 6 h, 24 h, and 3 days after decompression.Results:Totally six animals died before the end of the experiment (3 rabbits in ultrasonic imaging and microcirculation detection groups, respectively). Compared with the uninjured muscle, the reperfusion of the injured muscle showed early and high enhancement in contrast-enhanced ultrasonography images. The peak intensity and area under the curve were significantly higher than those of the control subgroup at each time point after decompression(all P<0.05), and reached the peak at 24 h after decompression. The time-intensity curve showed a trend of rapid elevation and gradual drop. In the microcirculation group, compared with the control group, fine artery and vein diameters in the experimental group were wider and the blood flow velocity was slower, especially in the fine veins(all P<0.05). At each time point after decompression, there was a statistical difference between the control subgroup and the control subgroup, and the change reached the peak at 24 h after decompression. The blood flow state showed that the arterioles were dominated by linear flow and linear grain flow at each time point after decompression, and linear grain flow, grain flow and grain pendulum flow were observed in the fine veins. Blood flow stagnation and adhesion of white blood cells and white microthrombus were also observed in the fine veins. Correlation analysis showed that the peak intensity and area under the curve were positively correlated with the inner diameter of arterioles and veins( r=0.84, 0.94; r=0.85, 0.94; all P<0.05), and negatively correlated with the flow velocity of arterioles and veins( r=-0.94, -0.96; r=-0.93, -0.96; all P<0.05). Conclusions:In vivo microcirculation detection can reflect changes in muscle microvascular diameter and blood flow velocity, which have a correlation with quantitative ultrasound imaging parameters.

Ultrasound-guided platelet-rich plasma injection for repair of sciatic nerve crush injury / 中国组织工程研究

BACKGROUND: Platelet-rich plasma (PRP) contains growth factors that affect tendon, ligament, muscle and bone healing. On this basis, researchers gradually realize that such molecules released after PRP activation can regulate the early inflammation of peripheral nerve injury, activate Schwann cells, promote the polarization of macrophages, and actively prevent the hyperplasia of collagen fibers, thus becoming the key drivers of nerve function recovery. OBJECTIVE: To evaluate the value of ultrasound-guided PRP injection in the repair of sciatic nerve crush injury. METHODS: Twenty-eight healthy New Zealand white rabbits (provided by the Beijing Longan Experimental Animal Breeding Center) were randomly divided into normal group, control group, single PRP group and multiple PRPs group. In the normal group, the right sciatic nerve was exposed and then sutured directly. In the control group, a compression injury model of the right sciatic nerve was established. In the single PRP group, autologous PRP was injected around the injured nerve under ultrasound guidance at 24 hours after modeling. In the multiple PRPs group, autologous PRP was injected around the injured nerve under ultrasound guidance at 24 hours after modeling, and then the PRP injection was performed once at the 3rd and 5th weeks after modeling. Histological and morphological observation of regenerated nerves, wet weight recovery and histological manifestations of the denervated muscle were evaluated at 12 weeks after modeling. The study protocol was approved by the Administrative Committee of Experimental Animals in PLA General Hospital with the approval No. 2015-x10-02. RESULTS AND CONCLUSION: The integral optical density values of NF-200 and S100 staining, myelinated nerve fiber density, myelinated nerve fiber diameter and myelin sheath thickness were significantly increased in the single PRP and multiple PRPs groups compared with the control group (all P < 0.05), and the multiple PRPs group showed better outcomes than the single PRP group (all P < 0.05), but was still inferior to the normal group (all P < 0.05). Compared with the control group, wet weight and cross-sectional area of muscle fibers significantly increased in the single PRP group and multiple PRPs group (P < 0.05), and the multiple RPRs group showed better outcomes than the single PRP group, but was still inferior to the normal group (P < 0.05). To conclude, ultrasound-guided multi-frequency injection of autologous PRP has a good effect on the repair of sciatic nerve crush injury.

Role of HMGB1 in Post-traumatic Endoplasmic Reticulum Stress in Rat Lung Tissues / 法医学杂志

OBJECTIVES@#To explore the role of high mobility group B1 （HMGB1） protein in the post-traumatic endoplasmic reticulum stress （ERS） in rat lung tissues.@*METHODS@#The rat model of acute lung injury was established by crushing the hind limbs of rats with standard weight. The first experiment was to divide rats into postural control group and crush groups （6 h, 18 h and 30 h after crushing）. The second experiment was to divide rats into postural control group, 18 h crush group, HMGB1 inhibitor sodium butyrate （SB） group and 18 h crush+SB group. The protein expression changes of HMGB1 and ERS- related proteins （GRP78, caspase-12, CHOP and IRE1α） in rat lung tissues were detected with Western blotting. Meanwhile, the pathological changes of rat lungs were observed by HE stain.@*RESULTS@#Compared with the postural control group, the expression levels of ERS-related proteins （GRP78, caspase-12, CHOP and IRE1α） and HMGB1 protein in rat lung tissues by crushing the hind limbs of rats were obviously increased. The protein levels reduced at 30 h after crushing but were still higher than those of postural control group and obvious pathological changes of acute lung injury were observed simultaneously in rats. Compared with the 18 h crush group, the expression levels of the ERS-related proteins and HMGB1 protein in rat lung tissues were attenuated in 18 h crush+SB group, and the pathological changes of rat lung injury began to alleviate.@*CONCLUSIONS@#HMGB1-ERS pathway activated by traumatic stress can lead to acute lung injury in rats.

Effect of pigment epithelium derived factor on NO and the expression of caspase-3 in retinal tissues of model rats with optic nerve crush injury / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To analyze the effect of pigment epithelium derived factor (PEDF) on nitrogen monoxide (NO) and expression of cysteine-containing, aspartate-specific proteases-3 (caspase-3) in retinal tissues of model rats with optic nerve crush injury.METHODS: A total of 60 SD rats were randomly divided into the blank control group, model group and PEDF group, with 20 rats in each group.Except the blank control group, the optic nerve crush injury rat models were established in the other groups, and left eyeballs were taken as samples.After successfully modeling, the model group were treated with intravitreal injection of 5μL of balanced salt solution while PEDF group were treated with intravitreal injection of 5μL of PEDF (0.2μg/μL).Two weeks later, the retinal tissues were collected, and changes of shape were observed under microscope after HE staining.The changes of NO level were measured by colorimetry assay, the expression of caspase-3 mRNA and caspase-3 protein was detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western-blot.RESULTS: HE staining showed that retinal tissues of the blank control group arranged neatly and clearly.Retinal ganglion cells (RGCs) arranged in a monolayer, and cells were oval, uniform in size and distribution, the cell nuclei were clear, closely arranged, with clear boundaries.The retinal tissues of the model group were sparse in shape, RGCs showed vacuolar changes, the overall number of cells was reduced, and cell nuclei of residual RGCs showed pyknosis and uneven staining.RGCs in PEDF group were with slightly edema and arranged closely, and the degree of injury was significantly milder than that in the model group.Levels of Caspase-3 mRNA and protein and NO levels in the three groups showed the model group > PEDF group > blank control group (all P < 0.05).CONCLUSION: The application of PEDF can down regulate the expression of Caspase-3 and NO in rates with optic nerve injury and reduce RGCs injury.

Value of contrast-enhanced ultrasound on assessment of limb muscle crush injury:an animal experiment / 中华超声影像学杂志

Objective To explore the diagnostic value of quantitative contrast‐enhanced ultrasonography(CEUS) for crush injury in the hind limb muscle of rabbits .Methods A totle of 120 New Zealand white rabbits were randomized to receive compression on the left hind limb for either 2 h( n =56) or 4 h( n = 56) to induce muscle crush injury ,another 8 animals were not injured and served as normal controls .CEUS parameters such as peak intensity(PI) ,area under curve(AUC) ,ascending slop(AS) and descending slop(DS) were measured at 0 5. h ,2 h ,6 h ,24 h ,3 d ,7 d ,14 d after decompression .Results Compared with the uninjured muscle ,reperfusion of the injured muscles showed early and high enhancement in CEUS .The time‐intensity curve showed a trend of rapid lift and gradual drop .The PI and AUC values differed significantly among the three groups and were positively correlated with serum and tissue biomarkers .Rabbits of the 4 h compression group showed significantly higher PI and AUC values compared with the 2 h compression group at each time points .Conclusions CEUS can effectively detect muscle crush injury and monitor dynamic changes of the injured muscle in rabbits .PI and AUC are promising diagnostic parameters for this disease .CEUS might play an important role in the pre‐hospital and bedside settings for the diagnosis of muscle crush injury .

The MESS: is it must.

Massive lower extremity trauma presents an immediate and complex decision making challenge. Significant advancements have made in the field of reconstructive surgery over the past 30 years. Severely traumatised limbs which would have been treated by primary amputation 20 years ago are beginning to be saved. On the contrary, such extensive reconstructive procedures may not always produce the best of results in terms of functional outcomes. Thus the management of a severely crushed extremity presents a therapeutic dilemma as whether to amputate or to attempt salvage. Methods: All Prospective study of 40 patients with severe crush injury to the lower extremities treated in Sri Ramachandra Medical College, Chennai between June 2012 and June 2014. The inclusion criteria were grade IIIb and grade IIIc open fractures of the lower extremity with a Mangled extremity severity score (MESS) of 7 and above with minimum of 12 months follow up. All the fractures were classified according to the Gustilo and Anderson classification system and Mangled extremity severity score. Out of the 40 patients 18 of them had their limbs salvaged and 22 underwent primary amputation. Results: The lowest MESS in this study was 7 and highest MESS was 12. The mean score in the limb salvage group was 8 and in the amputated group was 9.7. Complication rates in salvage group were higher. The mean SF score for amputated group for physical component summary was 40.15 and mental component summary was 44.30 while for limb salvage group score for physical component summary was 30.91 and mental component summary was 36.90. Conclusions: The MESS scheme provides excellent guidelines to the treating surgeon when faced with a dilemma of whether to attempt salvage or amputate a severely injured limb. The decision of whether to amputate or salvage an injured limb must be made very early in the course of treatment. This is because immediate amputation is most often viewed by the patient as a result of injury; whereas, delayed amputation is often considered as a failure of treatment.

Study on negative pressure wound therapy combined with moist wound therapy for traffic crush injury / 医学研究生学报

Objective Negative pressure wound therapy (NPWT) and moist wound therapy (MWT) are two new methods for wound care .Whether the united is better than the single .The study was to observe and compare the effects of using negative pres-sure wound therapy ( NPWT) combined with moist wound therapy ( MWT) and simple MWT in the treatment of traffic crush injuries . Methods 32 cases were randomly divided into two groups:intervention group and control group , 16 cases for each group .In interven-tion group, wounds were first treated by NPWT for 21 days, followed by standardized MWT till healing .In control group, wounds were treated by standardized MWT till healing .Consensus methods were applied in the measurements before treatment , 7 days, 14 days and 21 days after treatment .The measurements were involved in wound size , depth, undermined edge and the ratio of granulation tissue covering wound bed .Calculation were made on the construction rates of wound size , depth, volume and undermined edge along with re-cords of the time 100%granulation tissue covering wound bed and healing .The database was set up and statistical analysis were done by SPSS 16.0 software. Results The healing rate was 100%for both groups.During 21 days of treatment, the construction rates of wound size, volume, depth and undermined edge of intervention group were better than those of control group (P<0.05).The time 100%granulation tissue covering wound bed of intervention group was shorter than that of control group ([25.00 ±5.77] d vs [41.25 ±18.32]d, P=0.000).The healing time of intervention group was about two weeks shorter than of control group , but with no significance([67.63 ±22.38]d vs [83.56 ±55.31]d, P=0.597). Conclusion NPWT is applicable to traffic crush injuries in combination with MWT , which could promote the growth of granulation tissue and help construct and heal the wounds .NPWT combined with MWT has prior effects to simple MWT .

The experimental model of severe crush injury in rats by two hindlimbs compression / 中华急诊医学杂志

Objective To investigate a reproducible model of severe crush injury (CI) in rats.Methods A total of 50 clean grade male SD rats were randomly (random number) divided into 5 groups.Both hindlimbs of anesthetized rats were compressed by blocks weighing 3.5 kg,for 6 hours and followed by 3 hours of reperfusion on a specially notched device (group SP,n =10),ordinary compression (group NM,n =10) and simple control (group SHAM,n =10).Arterial tension,serum lactate,and potassium (K+),serum myoglobin (MB),aspartate transferase (AST) and alanine transferase (ALT),BUN and Cr were measured at 10 minutes after cannulaton,and 3 hours after release from compression.Muscles and kidneys were evaluated morphologically.Group D and E were treated in the same way and were observed for 72 h to get the survival rate of the NM group and the specially notched compression group.The SPSS 17.0 statistical software was used for statistical analysis,repeated-measures ANOVA analysis for the differences between groups,Kaplan Meier-estimator for survival analysis.Results The Specially notched compression produced a greater increase in serum lactate (F =39.626,P ＜ 0.05),AST (F =24.965,P ＜ 0.05),ALT (F =19.096,P＜0.05),BUN (F=7.938,P＜0.05),CR (F=14.787,P＜0.05) and MB (F=16.840,P ＜0.05) by the end of experiment than NM group and simple control group.The direct cellular damage and ischemia-reperfusion injury were found under microscope.In crush injury caused by specially notched compression there was acute tubular necrosis found at 24 hours after injury.Mortality rate in the NM group was 20％,whereas mortality rate reached 90％ in rats with specially notched compression (P ＜0.05).Conclusions It successfully developed a severe crush injury model in experimental rats,suggesting it is worthwhile to popularization.

Ineficácia da laserterapia aplicada no trajeto do nervo e nas raízes medulares correspondentes / Lack of effectiveness of laser therapy applied to the nerve course and the correspondent medullary roots

Objetivo: Verificar a influência da irradiação do laser de baixa intensidade na regeneração do nervo fibular comum de ratos após lesão por esmagamento. Métodos: Foram utilizados 25 ratos, divididos em três grupos: 1) nervo intacto, e não tratados; 2) nervo lesado, e não tratado; 3) nervo lesado, e laser irradiado sobre a região medular correspondente às raízes do nervo ciático e subsequentemente no trajeto do nervo lesado. A irradiação foi realizada por 14 dias consecutivos. Resultados: Foram avaliados por meio da análise funcional da marcha, através do índice funcional do peroneiro, e por análise morfométrica através do número total de fibras nervosas mielinizadas e sua densidade, número total de células de Schwann, número total de vasos sanguíneos e sua área, diâmetro mínimo da fibra e razão-G. Conclusão: De acordo com a análise estatística, não houve diferença significativa entre os grupos, e os autores concluem que a irradiação do laser de baixa intensidade possui pouca ou nenhuma influência na regeneração nervosa e recuperação funcional. Trabalho experimental.

Objective: To investigate the influence of low intensity laser irradiation on the regeneration of the fibular nerve of rats after crush injury. Methods: twenty-five rats were used, divided into three groups: 1) intact nerve, no treatment; 2) crushed nerve, no treatment; 3) crush injury, laser irradiation applied on the medullary region corresponding to the roots of the sciatic nerve and subsequently on the course of the damaged nerve. Laser irradiation was carried out for 14 consecutive days. Results: animals were evaluated by functional gait analysis with the peroneal functional index and by histomorphometric analysis using the total number of myelinated nerve fibers and their density, total number of schwann cells, total number of blood vessels and the occupied area, minimum diameter of the fiber diameter and G-quotient. Conclusion: according to the statistical analysis there was no significant difference among groups and the authors conclude that low intensity laser irradiation has little or no influence on nerve regeneration and functional recovery. Laboratory investigation.

Study of contrast enhanced ultrasound on muscle crush injury to extremity / 中华超声影像学杂志

Objective To explore imaging feature of muscle crush injury of extremity on contrast enhanced ultrasound (CEUS) by an animal experiment.Methods Twenty-eight New Zealand rabbits were anesthetized by intramuscular pentobarbital sodium (30 mg/kg).A special balloon cuff device was used to create left hind leg crush injury with a force of (18.6 kPa).23 of the 28 rabbits had crush injury of extremity and survived for 72 hours.CEUS evaluated infusion model and contrast intensity in crush region of hind leg at the 0.5,2,6,24 and 72 hour after the release of the crushing pressure.Peak intensity (PI) was analyzed by comparing with serum creatinekinase (CK) and myoglobin (MYO).Results Twenty-three rabbits presented that the area of crushed region in left hind leg was 60 cm2,accounting for 2.6％-3.0％ of body surface area.In different time after decompression,the crushed regions showed rapid enhancement and the intensity was higher than that of no-crushed region.The time-intensity curves of crushed regions all appeared as fast wash-in and slow wash-out.PIs of rushed regions were higher obviously than those of nocrushed regions (P ＜0.001).ROC curves were employed in diagnosis value of PI for crushed region.And PIs showed positive correlation with CK and MYO and the correlation coefficient was 0.833-0.996.Conclusions CEUS presents that the micro-circulation perfusion of the crushed muscle increased obviously after the release of the crush pressure.PIs evaluated quantitatively the micro-circulation perfusion changes.It suggests a potential alternative for evaluating micro-circulation abnormality and ischemia reperfusion injury of the muscle crush injury to extremities.

Landslide fatalities: A study of six cases.

A mountain collapsed on National Highway-53(NH-53) on 6th July 2011 around 2:30 p.m. A minibus which was carrying Security Personnel of Manipur Rifles (MR) and Indian Reserved Battalion (IRB) was hit by the landslide. Six occupants died on the spot and seven were injured. The cases were registered under U.D. Case no. 5/2011/G-SPM-PS and were brought to the RIMS Morgue the next day for Post Mortem Examination (PME). On PME, the victims showed general features of blunt force injuries with gross deformation and one case showed clogging of the whole respiratory tract with soil debris of the landslide. The victims died almost immediately on the spot due to vital organs injuries except in one case where it was due to traumatic asphyxia. Landslides occur frequently in these National Highways due to the hilly terrain and the perpetual rains, such major fatalities have never occurred before. Therefore the cases are reported here to analyze the types of injuries sustained, the causes of death and to discuss precautionary measures for prevention of further mishaps. This will also serve as an eye-opener to the magnitude of severity such a natural disaster.

Estimulação elétrica de alta voltagem em nervo ciático de ratos: estudo pelo IFC / High voltage pulsed current stimulation of the sciatic nerve in rats: analysis by the SFI

OBJETIVO: Analisar a eficiência do tratamento com a estimulação elétrica de alta voltagem (EEAV) em três diferentes locais, aplicada precocemente na regeneração do nervo ciático submetido à lesão por esmagamento, e avaliada através do índice funcional do ciático (IFC), em ratos. MÉTODO: Após o esmagamento, 57 ratos foram submetidos à EEAV catódica nos parâmetros: frequência de 50Hz, 100V de tensão, 20 minutos diários, 5 dias por semana. Os ratos foram divididos aleatoriamente em: grupo controle; grupo gânglio; grupo gânglio + músculo; grupo músculo e; grupo simulado. O IFC foi avaliado semanalmente durante sete semanas, partindo do pré-operatório até a 6ª semana pós-operatória. RESULTADOS: Em comparação ao grupo controle, os resultados mostraram desempenho significativamente superior do grupo gânglio nas três primeiras semanas, e do grupo gânglio + músculo na 3ª semana, enquanto o grupo músculo teve desempenho significativamente negativo na 4ª e 6ª semanas. CONCLUSÃO: a EEAV aplicada precocemente, foi positiva no tratamento da região da medula e gânglio da raiz nervosa do ciático com o eletrodo dispersivo na região lombar contralateral ou no músculo gastrocnêmio. Porém, proporcionou efeitos negativos no tratamento com eletrodo ativo no músculo gastrocnêmio e dispersivo na coxa contralateral. Nível de evidência II, Estudo prospectivo comparativo.

OBJECTIVE: To analyze the efficiency of high voltage pulsed current (HVPC) with early application in three different sites, in the regeneration of the sciatic nerve in rats submitted to crush injury, the sciatic functional index (SFI) was used to assess the functional recovery. METHODS: After crushing of the nerve, 57 animals were submitted to cathodal HVPC at frequency of 50Hz and voltage of 100V, 20 minutes per day, 5 days per week. The rats were divided into five groups: control group; ganglion group; ganglion + muscle group; muscle group; and sham group. The SFI was determined weekly for seven weeks, from the preoperative period to the 6th postoperative week. RESULTS: Compared with the control group, the results showed a significantly better performance of group 2 for the first 3 weeks; group 3 showed significantly better performance in the third week; and group 4 showed a significantly negative performance during the 4th and 6th weeks. CONCLUSION: Early application of HVPC had a positive effect in the treatment of the spinal cord region and the sciatic nerve root ganglion with a dispersive electrode on the contralateral lumbar region or on the gastrocnemius. However, HVPC had a negative effect in the treatment with an active electrode on the gastrocnemius and a dispersive electrode on the contralateral thigh. Level of evidence II, Prospective comparative study.

Muscle crush injury of extremity:quantitative elastography with supersonic shear imaging / 中华超声影像学杂志

ObjectiveToexplore the appearance ofmusclecrushinjuryatquantitative ultrasonographic elastography by supersonic shear imaging (SSI).MethodsThe animal experiment was done using a special balloon cuff device to create left hind leg crush injury with a force of 18.6 kPa.Twentythree New Zealand rabbits had crush injury of extremity and survived for 72 hours.SSI quantitative elastography was performed in crushed and no-crushed regions of each rabbit hind leg.Quantitative lesion elasticity was measured in terms of the Young modulus (in kilopascals) at 30 min,2 h,6 h,24 h and 72 h after the release of the crushing pressure.A receiver operating characteristic (ROC) curve analysis was used to assess diagnostic performance.ResultsThe area of crushed region in left hind leg accounted for 2.6％ -3.0％ of body surface area in 23 rabbits.The crushed regions exhibited maximum elasticity values of (19.51 ± 6.74)kPa,(21.47 ± 5.54) Pa,(11.36 ± 5.35)kPa,(15.09 ± 3.31)kPa and (13.72 ± 3.74) kPa,and mean elasticity values of (12.44 ± 3.77)kPa,(13.20 ± 3.60)kPa,(6.80±2.86)kPa,(10.04 ± 2.95)kPa and (6.94 ± 0.97)kPa at 30 min,2 h,6 h,24 h and 72 h after the release of the crushing pressure.Comparing with those of no-crushed regions,they were higher obviously (P＜0.001).ROC curves showed that extremity crush injury was diagnosed by using elasticity value,and the greater the elasticity value,the greater the diagnostic value.Conclusions SSI provides quantitative elasticity measurements,thus adding complementary information that potentially could help in crush injury characterization with conventional ultrasonography.

Relationship of compression area, time and weight with crush injury/crush syndrome in rats / 中华创伤杂志

Objective To investigate the relationship of compression area, time and weight as risky factors with local injury and systemic pathophysiological responses in rats so as to establish repeatable experimental model of crush syndrome. Methods A total of 144 male SD rats were divided into two groups, ie, mortality investigation group and biochemical indicator investigation group. Every group included the same 18 subgroups based on 18 kinds of combination with different levels of compression area (the right or both hind limbs), time (4, 6, 8 hours) and weight (2, 3, 4 kg). The circumference of the compressed hind limbs of all rats were measured and serum potassium (K+), serum creatine phosphokinase (CK), creatinine and carbamide were measured too before compression and three hours after decompression. Incidence of myoglobinuria of all rats was recorded. Muscles and kidneys were evaluated morphologically. Results The compressed hind limbs of all rats swelled significantly after three hours of reperfusion (P ＜ 0. 05). All serum K + , CK, CR and BUN were increased significantly with the increase and prolongation of the compression area, time and weight (P ＜ 0.05). Signs of direct cellular damage and ischemia-reperfusion injury were found in histology specimens of local compressed muscle.Hyperemia of glomeruli and renal tubule was found in the kidneys. Renal tubular necrosis and renal tubular cast were observed in group with compression weight ≥3 kg and compression duration ≥6 hours.Conclusions Increase and prolongation of the compression area, time and weight can aggravate the severity of crush injury. Compression area is more risky factor of severe crush injury. Both hind limbs ascompression area, compression weight ≥ 3 kg and compression duration ≥ 6 hours can be the effective experimental conditions for establishment of crush syndrome model in rats.

Research on the mechanism of brimonidine in the treatment of optic nerve crush injury / 眼科研究

Objective Present study aimed to research the mechanism of the use of 0.2% brimonidine tartrate eye drops in the treatment of optic nerve crush injury of rat.MethodsAnimal models of optic nerve crush injury were created in 60 SD female rats by clipping the exposed optic nerve at 2 mm in retrobulbar for 6 seconds with 78 grams of reverse forceps.The successful model was identified as Marcus-gun pupil without bleeding of fundus after operation.The animals were randomly assigned to model group and brimonidine treating group,and another 30 normal SD rats were used as the normal control group.The 0.2% brimonidine tartrate eye drops was topically administered at 2 hours before operation and after operation twice per day in the brimonidine treating group.The retinas from 18 rats were isolated after 3,7,21 days for RGCs counting by H&E staining,and the retinal ultrastructure was examined under the transmission electron microscope.The retinas from the other 72 SD rats (including normal,model and brimonidine groups) were prepared for the detection of bcl-2 and bax using immunohistochemistry l,3,5,7,14,21 days after the operation.ResultsNormal and almost normal retina structure was exhibited in rats of the normal group and brimonidine treating group,but disorder of cellular arragement and decrease of retinal thickness were found in the model rats under the optical microscope.The RGCs counting was significantly different among the three groups from 3 days through 21 days after operation with the considerably declination in the model group and brimonidine treating group compared with the normal control group (P＜0.05-0.01).However,that of the brimonidine treating group was obviously increased in comparison with the model group (P＜0.01).The expression of bax in rat retina was obviously reduced (P＜0.01),but the expression of bcl-2 was increased in brimonidine group compared with the model group from 5 through 7 days after operation (P＜0.01).ConclusionThe 0.2% brimonidine tartrate eye drops has a preventive effect on optic nerve crush injury of rat,and its inhibition on apoptosis is one of the mechanisms.

Adenoviral vector mediated in vivo gene transfer of BDNF promote functional recovery after facial nerve crush injury

Objectives Despite considerable advances in technique, experience and skill, the precise place of surgery in the treatment of facial nerve injury remains uncertain. We designed a facial nerve crush injury model in rats and evaluated the recovery of crushed nerve which is the most common injury type of facial nerve using adenovirus vector mediated in vivo gene transfer of Brain derived neurotrophic factor(BDNF). Materials and methods In 48 Sprague Dawley rats, we made a facial nerve crush injury model to main trunk before the furcation, and injected a 1011pfu adenoviral BDNF in experimental group(BDNF adenoviral injection group; ad-BDNF) and 3microliter saline in control group(Saline injection group; saline). After a period of regeneration from 10 to 40 days, nerve regeneration was evaluated with functioinal test (vibrissae and ocular movement), electrophysiologic study(threshold, peak voltage, conduction velocity) and histomorphometric study of axon density. Results Vibrissae and ocular movement, threshold and conduction velocity improved as time elapse in both group, however axon density was increased significantly only in experimental group. Functional test in 10 days and 20 days showed no difference between experimental group and control group. Vibrissae movement, threshold, conduction velocity and axon density in 30 days revealed that the regeneration in quality of experimental group was significantly superior to that of control group. Conclusion In general, there is tendency for nerve regeneration in experimental group (BDNF-adenovirus injection group) during 40 days, functional recovery was detected successfully after facial nerve crush in 30 days postoperatively.

The Neuroprotective Effect of Intravitreally Injected CNTF on Rat Retinal Ganglion Cell in Optic Nerve Crush Injury Model

PURPOSE: To make an optic nerve crush injury model and to investigate the neuroprotective effect of intravitreally injected ciliary neurotrophic factor (CNTF) on rat retinal ganglion cells (RGCs) in the model. METHODS: The optic nerves of 12 Sprague-Dawley rats were crushed at 3 mm posterior to the eyeball for 1 minute using aneurysm clip (110 g). Two micrograms of CNTF in 2 micro liter of vehicle was injected intravitreally in one group (n=6) and 2 micro liter of PBS was injected in the control group (n=6) at 4, 7, and 10 days after the optic nerve injury. After 2 weeks, the retrograde labeling of the RGCs was done by the dextran tetramethylrhodamine. Twenty-four hours after the labeling, the retina was wholly mounted and the labeled RGCs were counted under the fluorescence microscope. RESULTS: The death of RGCs in this model began at 1 week and continued for 3 weeks. The number of labeled RGCs in CNTF-injected group (510+/-139/mm2) were significantly higher than that in control group (345+/-87/mm2)(p<0.05). CONCLUSIONS: The optic nerve crush injury model was established by use of aneurysm clip. In this model, the intravitreally injected CNTF had a neuroprotective effect on the rat RGCs.

The Neuroprotective Effect of Ginexin on Rat Retinal Ganglion Cell in Optic Nerve Crush Injury Model

PURPOSE: To investigate the neuroprotective effect of Ginexin (Ginkgo biloba extract) on rat retinal ganglion cell in the optic nerve crush injury model. METHODS: From 1 week before the optic nerve injury, Ginexin 100 mg/kg/day (100 mg group), 200 mg/kg/day (200 mg group) or carboxymethylcellulose as a control group (CMC group) was administrated orally 4 weeks in Spraque-Dawley rats. At 3 weeks after the optic nerve injury, the RGCs were counted and the concentration of intravitreal glutamate was measured. RESULTS: The RGC density of CMC group (103+/-22 cells/mm2) was significantly lower than that of 100 mg group (182+/-39 cells/mm2) and 200 mg group (201+/-63 cells/mm2). There was no difference between the 100 mg group and 200 mg group. The concentration of invtravitreal glutamate did not significantly differ among normal, CMC group, 100 mg group and 200 mg group. CONCLUSIONS: Ginexin increased the survival of the retinal ganglion cell in rat optic nerve crush injury model, but, did not influence on the concentration of intravitreal glutamate.

The Effect of Heat Shock Protein 70.1 gene (hsp70.1) on Retinal Ganglion Cell Damage after Partial Lesion of the Optic Nerve in Mice

PURPOSE: Heat shock protein (HSP) 70 has been known to have neuroprotective effect on the retinal ganglion cells (RGCs) in vitro and in a rat glaucoma model. This study was to evaluate the inducible HSP70 expresseion in the retinal ganglion cell (RGC) after partial crush injury in mice and to determine the effect of hsp70.1 on the RGCs in the normal condition and after partial crush injury of the optic nerve. METHODS: The optic nerve was crushed by clipping optic nerve with aneurysm clip (110G) for 30 seconds. H and E staining and immunohistochemical staining for inducible HSP70 was performed in the hsp70.1 knockout mice and wild type mice. The RGC counts before crush injury were compared and the losses of RGCs after 3 weeks were compared between the two groups. Loss of RGCs was monitored as a percentage of cells decreased relative to the contralateral sham-operated eye. RESULTS: Immunohistochemical staining showed HSP70 induction in the RGC layer after optic nerve crush injury in both hsp70.1 knockout mice and wild type mice. RGC count before crush injury showed no significant difference (n=8, Mann-Whitney test), and the loss of RGCs was 31.0%+/-0.1% (mean+/-SD) in the hsp70.1 knock-out mice and 32.6%+/-0.1% in the wild type mice without any significant difference between the two groups (n=8, Mann-Whitney test). CONCLUSIONS: HSP70 was induced in the mice RGC layer by optic nerve crush injury and the hsp70.1 gene didn't affect the RGC counts in normal condition and RGC survival after optic nerve crush injury in the mouse.