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showed good bone reconstruction and 23% some subsidence (only three cases >1 cm) withoutclinical symptoms except for the necessity of a compensatory heel pad.Distal fixation stems like T3 are the implants of choice for severe bone stock loss (Paprosky2C-3) for their immediate mechanical stability allowing early weight bearing. Transfemoralapproach allows complete removal of debris and scar tissue, enhancing bone reconstruction, buta learning curve is necessary.Poster: 10A Novel Implant Modification for Post-Operative Hip Arthroplasty StemAnteversion Identification*George Branovacki - Midwest Orthopaedic Consultants, S.C. - Orland Park, United StatesKamran Sadr - University Of Illinois - Chicago, USAHassan Baydoun - University of Illinois at Chicago - Chicago, USAMichael Redondo - Midwest Orthopaedic Consultants S.C. - Orland Park, USADana Murphy - Midwest Orthopaedic Consultants, S.C. - Orland Park, USALuis Redondo - Midwest Orthopaedic Consultants S.C. - Chicago, USASam Chmell - University of Illinois at Chicago - Chicago, USAIntroduction*Email: george@branovacki.comThe technique for balancing a total hip on the femoral side involves positioning the stem tooptimize leg length, offset, and component rotation. While plain radiographs can measure postoperative leg length and offset, only a CT scan or MRI from the hip to the knee can determinestem anteversion by comparing femoral component rotation to the knee epicondylar axis. Thisis important information to obtain when planning a revision hip arthroplasty for instability or foracetabular revisions where the stem is well fixed.MethodsWe performed twelve total hip arthroplasties using a custom modified Zweymuller-typefemoral stem where the anteversion of the implant could be measured radiographically on postoperativestanding x-rays. Intra-operative surgeon assessment of stem anteversion was recordedas well. The radiographic measurements were validated based on post-operative CT or MRIscans performed within 3 weeks of surgery that measured the stem anteversion relative to thedistal femur epicondylar axis.ResultsThere were no peri-operative complications with a minimum follow up of 3 months. Theradiographically measured post-operative femoral stem anteversion was accurate to within 2degrees with a detectable range from 45 degrees of retroversion to 45 degrees of anteversion.Intra-operative assessment was less accurate when noted by the resident assist surgeonfile:///E|/ISTA2010-Abstracts.htm[12/7/2011 3:15:47 PM]