Application of spiral CT three dimentional reconstruction on developmental dysplasis of the hip in children

Objective To evaluate the value of surface shaded reconstruction (SSD) of CT scanning on developmental dysplasia of the hip (DDK). Methods Unilateral DDH in 39 cases was examined with Picker 2000S spiral CT to perform SSD of the affected pelvis. All patients were females with the age ranging from 3.5 to 8 years old ( average 4.25 years). Of 39 cases, 22 cases were complete dislocation the hip, 17 cases were subluxation of the hip. The measurement of SSD included of the depth and surface area of normal and affected acetabulum; the distances from the lowest point of the bottom of the acetabulum (O point) to the anterior end (A point) of the lateral margin of anterior acetabular column (OA), the middle point (point) of the acetabular roof (OB) and the posterior end (C point) of lateral margin of the posterior acetabular column (OC). Results In normal hip, the medial and lateral margin of the acetabular roof was overlapping, and in DDH, a bony defect was found in the lateral acetabular margin in