The Study Of The Functions Of The Ulnar Nerve Mesangial To Prevent Dislocation Of The Ulnar Nerve

Objective:In this study, by measuring the basic parameters of ulnar nerve mesangial and exploring the functions of ulnar nerve mesangial to prevent dislocation of the ulnar nerve, to provide a theoretical basis for the dislocation of the ulnar nerve and simple decompression of the ulnar nerve.Methods:We select have been diagnosed Cubital tunnel syndrome 20 cases, 14 males and 6 females, mean age 54.2 years, six cases of left elbow, right elbow in 14 cases.Inclusion criteria: clinical and physical examination confirmed cubital tunnel syndrome adult patients, height and weight symmetry, no elbow congenital malformations and severe trauma.Open the skin, subcutaneous tissue of the medial elbow with a15 cm long incision.Set three mode:Mode1:Just open the outer wall of the cubital tennel and the Arcuate elbow ligament(Fig. 1);Mode2:Based on Mode1,cut off part of the ulnar nerve mesangial, free the ulnar nerve, but retain parts of the ulnar nerve mesangial at the medial epicondyle;Mode3:Based on Mode 2,cut off the ulnar nerve mesangial, free the ulnar nerve completely. Measur the length and width of the ulnar nerve lace and the depth of sulcus for ulnar nerve in Mode2.Measur the positional relationship between the ulnar nerve and sulcus for ulnar nerve when elbow joint under different flexion angle(natural extension, flexion 45 °, flexion 90 °, extreme flexion) in three mode(Mode1, Mode2, Mode3).Based on the dislocation of the ulnar nerve,we record the point:ulnar nerve completely prolapsing out of sulcus for ulnar nerve denoted 2 points,ulnar nerve partially prolapsing out of sulcus for ulnar nerve denoted by 1 point, the ulnar nerve stay in the sulcus for ulnar nerve entirely denoted 0 point.Sum the scores when elbow joint under different flexion angle,we get the total score called Dislocation Index.Dislocation index under three mode are denoted DI1, DI2, DI3.Statistical the data mesured above by SPSS17.0.Calculation the mean and standard deviation( x ±s)of the different parameters of theulnar nerve lace.Use the paired t test to research the difference between the DI1, DI2 and DI3.Use the SPSS17.0 to research the correlation between the DI(Dislocation index of the ulnar nerve) and d(The difference between the width of the ulnar nerve lace and the depth of sulcus for ulnar nerve).Results:Measuring ulnar nerve lace parameters in Mode2, and all measured data are estimated reading to 0.1mm.The results showed that the mean and standard deviation of the ulnar nerve lace parameters were:the length of the ulnar nerve lace L3(25.33±2.90)mm,thewidth of the ulnar nerve lace L4(9.03 ± 1.20) mm,the depth of the sulcus for ulnar nerve D(6.45 ± 0.79) mm.In three mode, the ulnar nerve dislocation indexs are: DI1(0.6 ± 0.5); DI2(2.3 ± 1.1); DI3(4.6 ± 1.1).The ulnar nerve dislocation index in three mode are researched by paired t test results, p <0.01, ulnar nerve dislocation indexes were statistically significant in three modes.In mode1,ulnar nerve dislocation indexes DI1 and d were positively correlated(r = 0.824, p <0.01);In mode2 ulnar nerve dislocation indexes DI2 and d were positively correlated(r = 0.769, p <0.01);In mode3 ulnar nerve dislocation indexes DI3 and d were positively correlated(r=0.641,p<0.01);That is the ulnar nerve dislocation index DI and d(The difference between the width of the ulnar nerve lace and the depth of sulcus for ulnar nerve) were positively correlated.Conclusion:Ulnar nerve lace and ulnar nerve mesangial are fixed anatomic parts of the tubital tennel to prevent dislocation of the ulnar nerve.Ulnar nerve dislocation caused by anatomical factors, in addition to the arcuate elbow ligament laxity and sulcus for ulnar nerve too shallow two factors, the ulnar nerve mesangial too slack is another factor.Ulnar nerve dislocation index DI and d is directly proportional relationship, when thewidth of the ulnar nerve lace is greater than the depth of the sulcus for ulnar nerve, the significant increase in the probability of dislocation of the ulnar nerve.Ulnar nerve lace is the most important part of the ulnar nerve mesangial,which plays an important role in the limited activity in the ulnar nerve sulcus of the ulnar nerve.When the structure is too long,it will lead the ulnar nerve to prolapse out of the sulcus for ulnar nerve.When the structure is too long,it will cause nerve inadequate slide,resulting in ulnar nerve laced tightening and the ulnar nerve injury occurs. Too tight of the structure is a potential factor of chronic ulnar nerve injury.Simple decompression of the ulnar nerve is not suitable for the patients of elbow flexion and varus deformity, and ulnar nerve mesangial is too slack that the ulnar nerve dislocated.Too slack of the ulnar nerve mesangial is the contraindication of simple decompression of the ulnar nerve,and when the ulnar nerve mesangial is too slack,we should use ulnar neurolysis and the nerve anterior transposition.