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Massive bone loss is a problem frequently encountered during revision hip surgery. Several ways of addressing the bone loss in proximal femur have been described with varying results. We present our results with the use of a radial impaction grafting technique and a collared textured component. 107 consecutive cases of Revision Total Hip Arthroplasty, who underwent radial impaction grafting and had a textured collared implant inserted for femoral deficiencies were assessed. The average follow up was seven years and four months (3 to 11 years). All the patients experienced a significant improvement in the clinical scores. Oxford Hip scores improved from an average of 41.2 (30 - 56) to 19.3 (12 - 32). Harris Hip scores improved from an average of 40.8 (28 - 65) to 83.4 (60 - 99). There were no cases of subsidence at follow up. Using revision for any cause as the end point the survivorship at an average of 88.8 months was 93.8%. Three revisions were performed for deep infection within the first year. There were three cases of peri-prosthetic fractures distal to the tip of standard length stems at an average of 8.4 months after surgery. We recommend the use of morsellised allografts with radial impaction grafting and textured, collared stems for selected cases with Paprosky type II and type III femoral defects. We also recommend use of long stems bypassing the tip of the previous implant with impaction grafting to avoid peri-prosthetic fractures.

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REPORT DOCUMENTATION PAGEForm Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. REPORT DATE (DD-MM-YYYY) 24-02-2015 REPORT TYPE Technical Paper DATES COVERED (From -To DISTRIBUTION / AVAILABILITY STATEMENTApproved for public release A: distribution is unlimited. SUPPLEMENTARY NOTESCA: Air Force Flight Test Center Edwards AFB CA CC: 012100 ABSTRACTGeneralized time-reversed space-time block codes (GTR-STBC) are introduced as a conceptual tool to examine the impact of unequal power allocation in aeronautical telemetry channels. Two transmitting antennas are employed to exploit partial channel state information. GTR-STBC are observed to perform the best trade-off between the signal-to-noise ratio and inter symbol interference. It is also observed that the optimum transmitter power profile for the measured channel is significantly different than that in the statistical channel model. SUBJECT TERMS Md. Shah Afran Mohammad SaquibThe University of Texas at Dallas ABSTRACT Generalized time-reversed space-time block codes (GTR-STBC) are introduced as a conceptual tool to examine the impact of unequal power allocation in aeronautical telemetry channels. Two transmitting antennas are employed to exploit partial channel state information. GTR-STBC are observed to perform the best trade-off between the signal-to-noise ratio and inter symbol interference. It is also observed that the optimum transmitter power profile for the measured channel is significantly different than that in the statistical channel model.