The Treatment Of Femoral Bone Defect And Selection Of Prosthesis In Revision Total Hip Arthroplasty

Background and purpose:To investigate the treatment of femoral bone defect and selection offemoral prosthesis in revision total hip arthroplasty.Data and MethodsClinical information:From september2011to september2013,32cases(32hips) underwent the revision of total hip arthroplasty indepartment of orthopedic of china-japan union hospital of jilin university,including10males and22females. The age was48to77yeas old, average67.13years old.The revisions: aseptic loosening was23cases,femoral prosthesis subsidence was5cases,periprosthetic femoral fracturewas4cases. Previous femoral prosthesis type: cement10cases,uncement22cases.The time from initial surgery to revision suegery is63.12months(6months to25years). The separate criteria of preoperative isPaprosky: type I2cases,typeⅡ10cases,type ⅢA12cases,type ⅢB8cases.During surgery the classification is AAOS:type ⅡA6cases,typeⅡB2cases,type ⅡC4cases, type Ⅲ16cases,type Ⅴ2cases,type Ⅵ2cases.Methods：According to the X-ray of Harris prosthesis looseningclassification criteria, assessed the situation of prosthesis.Useing Harris score hip functional score in the preoperative and postoperative follow-upof patients,with the help of SPSS17.0evaluate the short-term curativeeffect of the revision THA.Results1. The treatment of femoral bone defect and selection of femoralprosthesis: according to the classification of Paprosky,IBG+proximalcoating ordinary biological prosthesis in2cases of type I;10cases defectsin patients with type Ⅱ,7cases of IBG+total coated long biologicalprosthesis,2cases of IBG+modular femoral prosthesis,1case of IBG+long cemented prosthesis;20cases defects in patients with typeⅢ A andⅢ B,9cases IBG+structural bone graft+modular femoral prosthesis;6cases IBG+structural bone graft+long cemented prosthesis;5cases IBG+structural bone graft+total coated long biological prosthesis;2.Harris score: All patients were followed up for12-58months,with an average of36months. Harris scores after12months from the(44.06±8.69) preoperatively, increased to an average of (83.97±6.17)points, excellent (>90points) in10cases, good (80-89points) in16cases, the (70-79points) in6patients, no difference of cases (<70points), good rate of87.5%. During follow-up, two cases which hadimpaction bone grafting combined with a long biological prosthesis, hadproximal femur bone mineral density and mild femoral prosthesissinking.1case which had a total coated long biological prosthesis appears high density in periprosthetic femoral prothesis. the remaining29cases were not found prosthesis′s loosening, implant subsidence, boneabsorption etc.Conclusion1.A preoperative Paprosky and intraoperative AAOS assessmentcriteria can help develop a scientific and rational surgery program.2.The difficulty in femoral revision lies in removing the prosthesisand bone cement,the extension osteotomy of the greater trochanter、femoral windows can assist to remove the prosthesis and bone cement.3.Femoral revision is focused on how to preserve bone mass andincrease bone mass and to ensure that the new femoral prosthesisimplanted with good initial stability, and can effectively improve thelong-term stability of the prosthesis.4.Based on our clinical studies, total coated long biologicalprosthesis especially for metaphyseal bone defects and the backbone areais not serious, for more serious patients should be carefully chosen;long-handled cemented prosthesis used for severe osteoporosis, lowactivity levels, bone less or more lenient femoral canal elderly patients;modular prosthesis suitable for patients with irregular metaphyseal andbackbone, has unique advantages in the treatment of femoral bone defect.