The Research Of Three New Measuring Method In The Diagnosis Of Adult Acetabular Dysplasia

Objective: Acetabular dysplasia is a kind of developmental malformation. Refers to the acetabulum developmental defect of acetabulum to femoral head cover bad, joint subluxation or dislocation of the trend, becomes shallow acetabulum, hip center offshoring 。 Wiberg first described acetabular dysplasia’s concept, he use centre edge angle diagnose adult acetabular dysplasia, centre edge angle≤ 20° can diagnose adult acetabulum hypoplasia. Measuring Method in the Diagnosis of adult Acetabular Dysplasia generally on the basis of pelvic X-ray,(anteroposterior position of pelvis) hip angle of CE, it is on the center to the outside of the acetabulum femoral head on the edge of attachment and acetabulum, it is also called center-edge Angle. This Angle is used to evaluate bony acetabulum in femoral head upper part and the outside of the cover. Normal adult’s CE Angle is between 20 to 25 degree, which less than 20 dergree is Acetabular Dysplasia. Sharp angle is on the X-ray plain film of pelvis. From the side of the acetabulum outer designated as “tears” tangent, on the same side and double side edge of the “tears” wired extension cord angle, referred to as the sharp angle. Normal human’s acetabulum angle is from 39 to 42 degree, which greater than 45 degree is Acetabular Dysplasia. Acetabular head index is the distance of the outside of the femoral head to the around of the acetabulum diamater than that of the femoral head. It is on behalf of the size of the femoral head and acetabulum depth incompatible with their status. The normal range is from 84 to 85. The average male is 86.22 percent, 87.59 percent for women. The limit is 76 percent. It is necessary to identify osseous tag clearly when measuring CE Angle, Sharp Angle, head of the acetabular index. Such as center of femoral head, acetabulum outer edge, femoral head and femoral head around the rim. Only in this way can we get the accurate results. But in the measurement of ascertain in landmark of bony, there are many errors.Moreover, the measurement of Angle increased the possibility of error. For this, we put forward three kinds of new measuring method to diagnose the adult’s Acetabular Dysplasia. 1、Offshoring index refers to the special value of the Center of femoral head and acetabulum respectively to the edge points on the body axis ratio. 2、Move the index refers to the special value of Center of femoral head and tears to the edge of sacroiliac joint point of the ratio. 3、Tears offshoring baseline index refers to the perpendicular distance of Center of the femoral head and acetabulum of edge points respectively to tears.Method: Choose X-ray of the patients in The third hospital affiliated to hebei medical university from 07,2013 to 07,2014 to measure. There are 438 examples in total, 241 men and 197 women. Accepting criteria: 1 Age greater than or equal to the age of 16 years old. 2 No hip replacement, the pelvis internal fixation or external fixation and Proximal femoral surgery. 3 No obvious pelvic tilt. 4 No hip dislocation.5 There are no obvious deformity in hip joint. Such as obvious collapse of the femoral head and severe traumatic sex arthritis of the hip. 6 There are no huge mass placeholder shadow in the pelvis and proximal femur. Using Photoshop app to measure each side of the hip about CE Angle of offshoring, sharp Angle, head of acetabular index, offshoring index, moving index, tears offshoring baseline index. Measured results using SPSS 19.0 Spearman rank correlation method to analyze.Result: The correlation between Offshoring index and CE Angle is high. The correlation between the moving index of men on the left side, women on both sides and CE Angle is low. It is high between men on the left side and CE Angle. The same between men and women both sides tears offshoring baseline index and CE Angle. Offshoring index and Sharp Angle has no relevance, Moving up index and Sharp Angle has no relevance, tears offshoring baseline index and Sharp Angle has no relevance. There is no significant correlation between offshoring and head mortar index, and moving up index has no correlation with head mortar index. Tears offshoring baseline index had no significant correlation between head mortar index and single is better than offshoring and head mortar index correlation. We use Sharp Angle as the reference standard 95 percent of credibility interval is from 83.13 percent to 90.51 percent of men on the right side, from 88.16 percent to 91.58 percent of men on the left side, from 88.60 percent to 91.13 percent of women on the right side, from 88.48 percent to 89.73 percent of women on the left side. The reference value of moving up index 95 percent credibility interval is from 71.40 percent to 80.30 percent of men on the right side, from 73.87 percent to 80.30 percent of men on the left side, from 72.75 percent to 76.80 percent of women on right side, from 73.70 percent to 78.35 percent of women on left side. The reference value of tears offshoring baseline index 95 percent of credibility interva is from 75.10 percent to 77.32 percent of men on the right side, from 74.76 percent to 82.01 percent of men on the left side, from 75.27 percent to 79.46 percent of women on the right side, from 74 percent to 76.53 percent of women on the left side.Conclusion:1 Offshoring index and tears offshoring baseline index has significance in the in the diagnosis of adult acetabulum dysplasia, and the measurement method is relatively simple2 Adults’ Offshoring index between83.13% and 90.51%, tears offshoring baseline index between 75.10% and 77.32%.