![]() Patients who are over the age of 8 years at the time of onset and have a hip in the lateral pillar B group or B/C border group have a better outcome with surgical treatment than they do with conservative treatment. Group B/C is considered when the loss of lateral pillar height is at 50%. In Group A, which has a better prognosis, there are no loss of height in the lateral third of the femoral head and little density changes in Group B, there is lucency and lateral height loss of less than 50% and in Group C, the most severe form, there is more than 50% loss of lateral height. Herring or lateral pillar classifications and the patient's age strongly correlate with the outcome. Classification of its severity can be assessed by radiographs. Most cases of Legg-Calvé-Perthes disease (LCPD) develop between the ages of 4 and 10 years ( Figure 3). Differences greater than 1.5 mm between the two sides are considered abnormal. The medial articular joint space is measured between the medial border of the femoral head or neck (when epiphysis is not ossified) and the acetabular platform. The most useful lines and angles that can be drawn in the pediatric pelvis assessing DDH are shown in Figure 2. Because eccentric position or delayed appearance of the ossific nucleus is a common finding in DDH, a new radiographic classification system has been developed by the International Hip Dysplasia Institute (IHDI), which uses the mid-point of the proximal femoral metaphysis as a reference landmark. It relies on the presence of the femoral head ossification center. The Tönnis method is the most widely used radiographic system to classify DDH. ĭespite the widespread of ultrasound, pelvis radiographs are still frequently used to diagnose and/or monitor DDH or for assessing other congenital conditions or bone tumors. The range of normal values is from 90 to 135° and is related to the infant's age. Lines are drawn from the highest point of the ischium to the most prominent point of the symphysis, joining at the inside of the pelvis. The symphysis os-ischium angle of Tönnis evaluates the pelvic position in the sagittal plane. In neutral rotation the ratio is 1 but is considered to be acceptable when it is between 0.56 and 1.8. Tönnis introduced a quotient of pelvic rotation by dividing the horizontal diameter of the obturator foramen of the right side and that of the left. Reliability of measurements increases if indicators of pelvic alignment are taken into account. Radiographs of infants should be obtained with the pelvis in neutral position with the lower limbs held in neutral rotation and slight flexion.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |