The Hemodynamic Change In Nutritional Artery Flap Of New Zealand Rabbits After Sural Nerve Surgery

[Objective]To investigate the changes of the accompanying nutritional artery diameter of the New Zealand rabbits after sural nerve surgery and the pathophysiological changes of hemodynamics in the microvascular area of the arterial supply flap.What's more,the survival rate of the flap was analyzed between the nerve transection group and nerve preservation group surgical methods.Comparing their results whether there are differences of macroscopic and microscopic,and ultimately compare the significance of the two surgical methods approaches to clinical treatment.[Methods] Six New Zealand rabbits weighing about 3 months old and weighing 2.0kg-2.5kg were injected with red latex after abdominal aortic intubation,and the related structures of hindlimb sural nerve and its accompanying nutritional artery were dissected for anatomical study.Two New Zealand white rabbits were sacrificed and the sural nerve vessels were taken.Twenty New Zealand white rabbits(40 side hindlimbs)were randomly divided into the nerve transection group and nerve preservation group.The hindlimbs of the 20 sides of two groups were divided into four subgroups and respectively according to the postoperative time points 1,3,5 and 7 d.After the nerve transection group flap cutting,in the ipsilateral popliteal fossa to take a length of about 1cm longitudinal incision,blunting separation layer by layer,until the origin of sural nerve revealed in the popliteal fissure,then cut 1cm of nerve tissue.The control group that retained the nerve did not interfere the sural nerve after the flap was lifted,retaining its complete continuity.After pedicled flap surgery,each group is performed in situ suture.When around perioperative,be attention to aseptic operation.Then animals were sacrificed at the corresponding time points,and TH(Tyrosine hydroxylase)immunohistochemical staining,western-blot and glyoxylic acid staining were used to detect the sural neurovascular bundle.And theaverage temperature of the flap were measured by infrared thermography.[Results] Through the general anatomical observation,in the New Zealand rabbit hindlimbs,middle of femur,deep of musculi biceps femoris,the sural nerve is branched out by tibial nerve,which was measured under the hip,knee and ankle joint flexion at 90 ° position.it's about 9.8 ± 2.0 cm from the tip of the lateral malleolus,and its diameter is approximately 0.9 ± 0.2 mm at the starting point of the sural nerve.Then the sural nerve walk about 2.5 ± 1.1cm through popliteal fossa to the deep surface of gastrocnemius muscle sarolemma,and the sural artery and small saphenous vein formation of neurovascular bundle and accompanied by each other.At the distance from the tip of the lateral malleolus of 4.5 ± 1.2cm,the sural nerve pierces the sarcolemma(about the gastrocnemius muscle and tendon over the department),where the nerve diameter is 0.6 ± 0.2mm,which enter into the lower leg of the 2/3 part of the lateral subcutaneous tissue,and the trunk comes into the foot between the heel and the lateral malleus.In the experimental group,the specificity of the neurotransmitter protein tyrosine hydroxylase showed a time-dependent,It was found that the number and coloration of the specific particles of the sural nerve and the outer membrane of its accompanying artery were significantly decreased in height consistency at 1d,3d,5d and 7d under the immunohistochemical conditions.A similar result was obtained in the chemiluminescence experiment induced by glyoxylic acid.In the experimental group,there was a high degree of consistency between the fluorescence spots and the fluorescence intensity in the sural nerve and the outer membrane of its accompanying artery,The fluorescence scores of the experimental group were significantly different(F = 13.563,P = 0.004).Compared with the control group,The Immunohistochemical specific protein staining and the fluorescence intensity of it were not significantly changed.The flap temperature trend of these two groups were similar to the "S" curve,which wasn't stable at a high level until 8hours after surgery,what's more,the average temperature of the flap of nerve preservation group was lower than that of the nerve transection group.It was showed that the difference of the results of T test was statistically significant(P <0.05).[Conclusions] From the sural nerve issued by the tibial nerve branch,there are sympathetic fibers distributed in its accompanying blood vessels,nutrition and regulate its accompanying vasomotor function.In the popliteal fissure cut off the starting point of the sural nerve,proximal pedicle sural neurovascular flap microcirculation can be improved accordingly,and the survival rate of the flap compared with nerve preservation group may increase.