Clinical And Relevant Anatomical Study In Buttock's Myofascial Pain

Objectives:1.To provide anatomical evidence for localization and treatment of buttock pain;2.Provide reference for the diagnosis and therapy of gluteus medius myofascitis.3.To provide anatomical evidence for clinical sacral canal injection.Methods:1.The buttock was divided into four level by Line A,C,D,E and F.Line A is that the line between the two posterior superior iliac spines,the four lines were drawn as follows:C(1.5cm below A),D(3.5cm below A),E(5.5cm below A),F(7.0cm below A),Line B is that the perpendicular through the top of the left or right iliac crest, which is the outer limits,the anatomical position of the gluteus maximus,the gluteus medius,the piriformis were observed on twelve adult antiseptic corpses.2.1) 70 cases of normal adult(40 men and 30 women) were selected.Each tender point of homolateral gluteus maximus and piriformis and four tender points of gluteus medius(recorded as Point 1,2,3 and 4 shown in the figure) were chosen as the research target.The corresponding positions were pressed by the thumbs under the pressure of proximately 5Kg.Record the relevant pain by the VAS Pain Question- naire.2) 40 cases of patients with gluteus medius myofascitis(18 men and 22 women) were selected.Record the relevant pain grade by the method listed above(the highest tender pain grade was selected concerning gluteus medius).The data were analyzed by SPSS 13.0.3.The shapes of the sacral hiatus were observed on 112 cases of dry adult sacrums, the distance of the pairs of sacral horns,the sagittal diameter of the sacral hiatus, the distance of the superior border of sacral hiatus and the superior border of coccyx,and the depth of the sacral hiatus were measured and classified.The results were analyzed by SPSS 13.0.Results:1.The gluteus maximus and the gluteus medius can be found in four levels,while the piriformis only appears in both level E and F.2.1) In normal adults,the tender point of piriformis was the highest one,with gluteus maximus the lowest.Point 2 showed the highest grade in the four tender points of gluteus medius(2＞1＞4＞3).The above two showed no significant difference.As to gluteus medius,the pain grades of Point 1,3 and 4 had significant difference compared with that of piriformis.The grade of Point 3 was significantly lower than that of piriformis.2) In the patients group,the grade of Point 2 in gluteus medius showed significant difference to the grade of piriformis tender pain(P＜0.05).The former one was higher than the latter one obviously.3.Most shapes of the sacral hiatus were acuate or anomalistic,and their height was from sacral hiatus to S₄.The pairs of sacral horns were almost symmetrical and of the same height.Most of the dissymmetrical ones were deviated to left.coccyxsacralization ones composed of most of the sacrum variation.Compared to the female group,male's distance of the pairs of sacral horns is broader,there are statistical significances(P＜0.05) between the two groups. Conclusions:1.Most of the pain in buttock clinically should be considered as the pain of muscular fasciae of the gluteus medius,not the piriformis syndrome.2.1) In normal adults,Point 2 showed the highest grade of tender pain in gluteus medius(2＞1＞4＞3),equivalent to piriformis.2) In patients with gluteus medius myofascial pain,the tender pain grade of gluteus medius is significantly higher than that of piriformis.The clinical buttock pains are not all resulted from piriformis syndrome.The diagnosis should refer to the related position of the tender pain.3.The variation of the sacral hiatus is not unusual.In order to inject into it accurately and gain better effect,above the indexes should be considered.