Ultrasonographic Application On Developmental Dislocation Of The Hip In Infants Of Different Age

PurposeThe changes of correlative ultrasonic parameter index of normal hips and abnormal hips with developmental dislocation of the hip (DDH) in infants of different age were discussed in order to provide objective information for the diagnosis and treatment of DDH.Materials and methods378 normal hips and 244 hips with DDH among 622 hips of 311 infants were detected by ultrasonography(US).The morphology and structure information of hips were observed, and the values of ultrasonic parameter index, including angleα, angleβ, acetabular index(AI),femoral head percentage of cover(FHC)of normal hips and abnormal hips were measured. All the measurement findings of every parameter index were collected, sorted and divided into different groups by 3 months a group according to the age of the infants, then were statistically analyzed. The analysis included the comparison of the values of every parameter index between different groups,the correlation of the values between different parameter index , as well as the correlation between the values of every parameter index and the infants'age .The hips with treatment under frog position were monitored in the curative course by US to evaluate the using value of US in treatment of DDH.Results1. Morphology and structure, position relation between femoral head and acetabulum of the hips were demonstrated by US impersonally and clearly. Normal or abnormal hips, the degrees of abnormal hips and the types of hips could be judged according to the findings of US; 2. Analysis of values of parameter index of normal hips:①There was significantly statistical significance in the values of ultrasonic parameter index ,such as angleα, angleβ, AI, FHC of normal hip between the groups of different age(P<0.01);②There was correlation between the age and the values of every parameter index, among which angleα, FHC have positive correlation with age (the correlation index were 0.537 and 0.554 separately ) while angleβand AI negative correlation (the correlation index were -0.465 and -0.424 separately ).These means the values of angleα, FHC of normal hips become lager with the infants'growth and Angleβand AI become smaller;③There was correlation between the values of different parameter index . Both angleβand AI have negative correlation with angleα, the former correlation index was -0.277,while the latter closely, was -0.794;3. No statistical significance was found between the ultrasonic values of every group under different ages of different type abnormal hips(P>0.05), But closely negative correlations existed between angleαand AI, the correlation index was -0.800 in developmental dysplasia hips, -0.778 in subluxation hips and-0.741 in dislocation hips;4. The demonstration of position relation between femoral head and acetabulum of the infants treated under frog position could be obtained by US satisfactorily, to evaluate the status of closed reduction, especially in the cases with subluxation hips and dislocation hips. Meanwhile, the changes of ultrasonic parameter index in the course of treating were monitored dynamically together with the infants'age to evaluate the curative effect, and to direct the clinical treatment.Conclusions1. US can be viewed as an early definite and a screening method of diagnosing DDH. For older infants (above 6 months) it will be more accurate to analyze the ultrasonic parameter index together with the age of infants;2. US can be used as a routine examination method to monitor the course of treatment dynamically and to provide more objective evidence for clinical treatment.