Different Minimally Invasive Methods For The Treatment Of Different Stages Of ONFH: A Clinical Follow-up

ObjectiveTo study the clinical effect of minimally invasive surgical techniques in the treatment ofosteonecrosis of the femoral head(ONFH), to evaluate practical value of this strategy,and tostudy the indications of our applied approaches in various stage of ONFH.MethodsFrom July2003to October2009,50patients(61hips) who were cnnfirmed to beosteonecrosis of the femoral head underwent minimally invasive surgery.There were32males and18females with average of47.3years,ranging from20to81years. According to theAssociation Research Circulation Osteous (ARCO),three hips withⅠA stage, one hip withⅠBstage, two hips withⅠC stage, four hips withⅡA stage, one hip withⅡB stage, six hips withⅡCstage, eight hips with Ⅲ stage, thirty-five hips with Ⅳ stage. According to the etiologyclassification,twenty-one hips with steriod induced, twenty-six hips with alcohol induced. Thepre-collapsed patients whose lesion size were＜1/3underwent the porous tantalumimplant,with or without nonvascularized iliac bone grafting. The pre-collapsed patients whoselesion size were＞1/3received percutaneous multiple small-diameter decompression anddrilling. All the pro-collapsed patients underwent total hip arthroplasty.Clinical effects evaluationwere Harris score,range of motion and incidence of complication,and patients’ follow-ups wasthree years or more.By means of Logistic Regression Analysis, try to analysis the independentrisk factors related to the clinical result of joint-preservation procedures.Femoral heads survivalrates were calculated by means of Kaplan-Meier method.Formulate the new grading system ofosteonecrosis of the femoral head through hip arthroscope preliminarily,and compared withARCO staging system using spearman ranking correlation analysis.ResultsFifty patients(sixty-one hips) were available for followed-up at least3years,meanfollowed-up time was47.7months.The average pre-and post-operative Harris score were61.6±7.5points and88.6±10.6points respectively, at three years follow-up injoint-preservation group.There were five hips failed at five months,fifteen months,sixteenmonths and twenty-eight months postoperatively in joint-preservation group,total survival rate was75.0%. The average pre-and post-operative Harris score were41.3±10.2points and82.2±11.6points respectively, at three years follow-up in THA group.There were notcomplications happened.Necrotic area1/3was independent risk factor to failure ofjoint-preservation procedures. The new grading system of osteonecrosis of the femoral headthrough hip arthroscope has positive relationship with ARCO grading system.ConclusionMinimally invasive surgical techniques were appropiate in the treatment of osteonecrosisof the femoral head. The tantalum screw implant, hip arthroscope debridement,and smalldiameter multiple drilling were minimally invasive techniques,which could reduce bloodloss,hospital stay,and recovery time.The lesion size and ARCO stage played an important role inthe determination of surgical procedures. The patients wth necrotic area>1/3have lessimpossibility to obtain satisfactory outcome.We recommend the new grading system ofosteonecrosis of the femoral head through hip arthroscope.