Studies On Acetabular Development After Closed Reduction In Developmental Dysplasia Of The Hip And The Influencing Factors Of The Acetabular Development

OBJECTIVEThrough retrospective study, to observe the clinical therapeutic effect for closedreduction treatment of DDH, which have been used by Prof. Lin Qingjian; to dynamicanalysis the characteristics of acetabular development after closed reduction in DDH; to explorethe influencing factors of the acetabular development after closed reduction, and screen themajor influencing factors, then analyze them; to provide theory reference for improving thetherapeutic effect for closed reduction treatment of DDH.METHODSFollowing-up 100 half DDH children who have been treated by "the treatment mode ofclosed reduction" of Prof. Lin Qingjian from January 2002 to December 2005, their age from6 months to 36 months, dividing the age into 5 age groups by per 6 months, using four levelfunctional evaluation criterion to assess the clinical therapeutic effect. Grouping lesional andhomeochronous normal hip to pair, dynamic measuring AI and AI(D/W) in each age groupsof lesional and normal hip on before reduction,after reduction 3rd month,6th month,9thmonth,12th month, describing the characteristics of acetabular development in each agegroups on every observation time-points, comparing the difference of lesional acetabulardevelopment with normal acetabular physiological development. Investigating the followingfactors: gender,side,age,lesional AI before reduction,lesional AI(D/W) before reduction,dislocation level,the wide rate of femoral head,lesional femoral neck anteversion beforereduction,h/b rate,cut off adductor and skeletal traction et al. The 10 factors was taken asindependent variable, AI and AI(D/W) on the 12th month were taken as dependent variable,then using multiple linear stepwise regression analysis to analyze. All the data processing was completed by SPSS 12.0.RESULT(1) 100 half DDH children was treated by closed reduction treatment, the total excellent ratewas 88%. (2) After 1 year reduction treatment, lesional average AI decreased from 37.17°to27.02°, with a average reduction of 10.11°; lesional average AI(D/W) increased from 22.06%to 29.80%, with a average growth of 7.74%. Both rate of lesional AI decay and velocity oflesional AI(D/W) increase were obviously faster than rate of normal side physiologicaldevelopment. (3) After 1 year reduction treatment, comparing lesional average AI reductionwith lesional average AI(D/W) growth in every durations per 3 months: the difference aboutaverage change of AI,AI(D/W) during 1 to 3 months,10 to 12 months and 4 to 6 months,7to 9 months were very significant(P＜0.01), between 1 to 3 months and 10 to 12 months,between 4 to 6 months and 7 to 9 months were not significant (P＞0.05). The rate of AI decayand the velocity of AI(D/W) increase during 1 to 3 months,10 to 12 months were obviouslyfaster than other durations. (4) After 1 year reduction treatment, comparing lesional average AIreduction with lesional average AI(D/W) growth in each age groups: the difference aboutaverage change of AI,AI(D/W) among 7 to 12 months,13 to 18 months and 19 to 24months,25 to 30 months,31 to 36 months were significant (P＜0.05), the difference aboutaverage change of AI between 7 to 12 months and 13 to 18 months were significant (P＜0.05),the difference about average change of AI(D/W) between 7 to 12 months and 13 to 18 monthswere not significant (P＞0.05), the difference about average change of AI,AI(D/W) among 19to 24 months,25 to 30 months and 31 to 36 months were not significant (P＞0.05). The rate ofAI decay and the velocity of AI(D/W) increase in 7 to 12 months,13 to 18 months wereobviously faster than other age groups. (5) Age,gender,dislocation level,h/b rate,the wide rateof femoral head and femoral neck anteversion exerted obviously influence on lesional AI andAI(D/W), age,dislocation level and FNA were positive correlation of AI and negativecorrelation of AI(D/W), the wide rate of femoral head and h/b rate were netative correlationof AI and positive correlation of AI(D/W), the acetabular development of female was fasterthan male.CONCLUSION(1) "The treatment mode of closed reduction" of Prof. Lin Qingjian has simple operatingconditions and fine therapeutic effect, which is worth to be recommended. (2) After 1 year closed reduction treatment, rate of lesional acetabular development is obviously faster thanrate of normal side physiological development. (3) After 1 year closed reduction treatment,the crest-time of lesional acetabular development is during the 1 to 3 months and 10 to 12months. (4) In 7 to 36 months DDH children, the rate of lesional acetabular development isfastest under or equal to 18 months, the potentialities of acetabular development is diminishedexceed 18 months. (5) Age,gender,dislocation level,concentric reduction or not,thedevelopment degree of femoral head before reduction and proximal femoral morphous are themajor influencing factors of acetabular development.