| [Objective]:To design a safe,perfect operating approach and provide anatomical basis for neuroendoscopes surgery from occipital horn in lateral ventricle by simulating endoscopic surgery so as to decrease the neopathy and extend the indications.[Materials and Methods]:1.experimental object:The structures of occipital horn of lateral ventricle of 15(30 sides) native adult cadaveric head specimens which were fixed by 10%formalin and provided by Department of human anatomy of Kunming Medical University were observed and measured by simulating endoscopic surgery.Male or female was not limited and left or right side was at random.After the brain tissue were taken intact and sectioned in the horizontal plane with the brainstem removed from the tentorium cerebelli ceasma,the leptomeninges were obversed and gently removed.Fifteen whole taken brains were cut vertically just rostral to the splenium of the corpus callosum,thereby passing through the atrium of the third ventricle.In this way,the lateral view of the lateral ventricle could be seen clearly. With the further dissection,the contour of the occipital horn had been exposed for easy observation.The pathway from the body surface to the triangular area was designated as line A,and the pathway from the triangular area to the central part designated as line B,the pathway from the triangular area to the inferior horn designated as line C.2.experimental method:The scalp of specimens should be removed.On the surface of skull,we located the anchor points which were 3cm lateral from the brain middle,3cm,4cm,5cm,6cm,7cm,8cm supra from the external occipital protuberance and designated them Z1,Z2,Z3,Z4,Z5 and Z6 respectively. After drilling on the skull,those points were marked and the cranium was sawed off along the line of the pores acusticus externus,the external occipital protuberance and the arcus superciliaris.3.anatomical parameter:Puncturing from the different anchor points,the related structures including veins,arteries,cranial nerves and their normal anatomic variants(such as the cerebral duramater,the superficial cerebral veins,the parietooccipital artery,the calcarine sulcus artery,the angular gyrus,the optic radiation) were observed and the brain tissue thickness,the included angle formed by the pathway and the site where the anterior extremity of the transfixion pin could reach were compared.In this way,we could attain some data which were dealed with via statistical software SPSS 11.5 and were denoted in the form of Mean±SD for the measurement data.Analysis of variance with repeated measures,t-test and the chi-square test for the enumeration data were used for overall statistical analysis to evaluate these data that helped to describe the potential neopathy and advantages or disadvantages of the operating approach.P＜0.05 was considered significant.[Results]:1.The relationship between the anchor points and the vessel of the cerebral dura mater.The area where all the anchor points were located were not adjacent to the blood vessel of the cerebral duramater.2.The veins on the surface of the brain could be exposed clearly after the removal of the cerebral duramater.The results showed that Z5 and Z6 were adjacent to the superior anastomotic vein.Z5 was just located rear to the superior anastomotic vein with the distance of(4.54±0.84) mm;Z6 was rear to the superior anastomotic vein with the distance of(5.98±1.89) mm.The left were not adjacent to the superficial cerebral veins.3.We tested each specimen and there was a fairly long distance to the angular gyrus when puncturing from Z1,Z2,while Z3～Z6 were not safe(P＜0.05).Z3 was the nearest to the angular gyrus among them(P＜0.05):(8.44±5.29) mm.4.The parietooccipital artery and the calcarine sulcus artery are the two branches of the arteria cerebri aborales.Every pathway could meet them which both went deep in the bottom of the fissure.And the distance between the deepest place where the two arteries were and the median sagittal plane was measured:parietooccipital artery: (18.00±2.01) mm,calcarine sulcus artery:(24.02±3.16) mm.5.Puncturing from Z1～Z3,including three pathways,the superior and middle part of the optic radiation could be traversed.Whereas Z4～Z6 would be considered safe as far as the optic radiation was concerned.6.If line A was considered as the base line,there must be an angle when the transfixion pin changed its direction from the base line to the central part or the inferior horn.As showed in the result,the bigger included angle formed from the trigone to the central part was Z5 and Z6(P＜0.05),and the bigger included angle formed from the trigone to the angulus inferior was Z1 and Z2(P＜0.05).7.Specimens simulated the endoscopic surgery demonstrated that before reaching the surface of the cerebrum,all the structures punctured were the skin,the fascia superficialis,the aponeurosis of occipitofron tails muscle,the loose connective tissue,the periosteum,the skull and the mater.In our study,we had the thickness from the skin to skull measured which was(22.24±1.81)mm.In contrast to the thickness from the skin to skull,the brain tissue thickness of three radial lines A,B,C,was considered to be various about different radial lines and anchor points.The brain tissue thickness from Z1～Z6 to the trigone,the central part and the angulus inferior (line A,B,C) was not significantly different(P＞0.05),and the three pathways was compared B＞C＞A.8.By observing the position relationship between the occipital horn and the anchor points,Z4,Z5 and Z6 were easy to reach the anterior horn,while Z2,Z3 and Z4 were easy to reach the inferior horn.[Conclusion]:1.It is suitable to deal with the affection in the triangular area through the occipital horn of the lateral ventricle because of the minimal damage.2.Direct experimental evidence has been presented in support of the anchor point which is located 3cm lateral from the brain middle and 6～7cm supra from the external occipital protuberance for the neuroendoscopes surgery from the occipital horn in the lateral ventricle with the direction of transfixion pin pointing to the midpoint of the homolat arcus superciliaris and the depth of brain thickness was about (45.10±6.60) mm.There was little danger about the injury of nerve and blood vessel of the operating approach which can not only reach the triangular area directly,but also deal with the affection in the central part and the inferior angle beneficial to explore the other two regions during the operation. [Objective]:To analyze the causes of screws breakage and the screw which tends to being broken in the biomechanical study of internal fixation with steel plates for the treatment of femoral shaft fracture by applying the optical measurement in order to provide the mechanical basis for its optimization program.[Materials and Methods]:1.experimental object:6 native adult cadaveric femoral bone specimens which were fixed by 10%formalin provided by Department of human anatomy of Kunming Medical University were used.Male or female was at random,and left or right side was at random,too.2.experimental model and group:Femurs with all soft tissue cleared and the distal tip coated by dental base acrylic resin powder were desected at their midposition with scroll saw vertically to make the fracture model.Ten conditions were designed simulating to compare the experimental model:a.the cured fracture(integrity);b.the internal fixation of compression steel plates(segmentation);c.a proximal screw was removed-based on b;d.a distal screw was removed based on c;e.a proximal screw was removed based on d;f.a distal screw was removed based on e;g.a proximal screw was removed based on f;h.a distal screw was removed based on g;i.a proximal screw was removed based on h;j.a distal screw was removed based on i. Then the specimens were fixed and installed on MTS machine with femoral head clamped as the superior extremity and condyles of femur clamped as the inferior extremity.The load of 50N was applied in advance to remove the loosening and creeping.Subsequently,the axial load was applied 0～500N at 10N/ sec and the computer recorded the bias automatically.The calculation of bias and the mean straining was based on the digital speckle correlation method(DSCM) when loaded and the correlated screws were compared.In the test,we could attain some data which were dealed with via statistical software SPSS 11.5 and were denoted in the form of (Mean±SD).Analysis of variance with repeated measures and the T- test were used for overall statistical analysis to evaluate the data.P＜0.05 was considered significant.[Results]:(1) It was significant of the bias and the mean straining between the condition a and the condition b when loaded(P＜0.05),especially the condition b (P＜0.05).(2) As showed in our study,there were little bias in the ten screws under the condition b when the axial load was applied.And the bias was increased with the load.Screw 5,6 had made the greatest bias which were just located near to the two fringes of fracture line(P＜0.01).When compared between two screws,there was no significance between screw 1 and 10,2 and 9,3 and 8,4 and 7,5 and 6 (P＞0.05),and the left were significant(P＜0.05).(3) The bias and the mean straining of screw 5,6 increased gradually from condition c to j(P＜0.01),especially, condition g to j(P＜0.01).[Conclusion]:1.When the steel plate for the treatment of femoral shaft fracture is used,more than six pores of steel plate should be chosen to reduce its stability loss avoid leading to the breakage of screws.The two screws which were just located near to the two fringes of the fracture line will bear more stress and collapse easily.All the screws should be fixed along the straight line and the direction of those symmetry screws should be coherent so as to avoid producing torsion and unbalanced load resulting in the breakage.Otherwise,the functional exercise of patients should be made after the callus formation.2.Digital Speckle Correlation Method is an effective technique of photology and mechanics to measure the facial disfigurement of objects through the image collection,image digitization,dealing with two different pattern under the deformed condition or moment so as to obtain the bias and gradient.By introducing this method to the empirical study of biomedicine,the development of medical research can be improved,which implies DSCM is an important method deserving generalization. |
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