[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-435497-105":59,"doc-detail-435497-en":134},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":127,"head_meta":129,"extra_data":131,"updated_unix":133},105,"en","espinoza-technique-leads-to-excessive-retroversion-in-piriformis-fossa-entry-nailing-computed-tomographic-analysis","Espinoza technique leads to excessive retroversion in piriformis fossa entry nailing - computed tomographic analysis","","Clinical investigation evaluates whether the Espinoza technique—aligning femoral rotation to the intramedullary nail’s inherent anteversion—produces equivalent reliability when using piriformis fossa (PF) versus greater trochanter (GT) entry portals. A retrospective computed tomography analysis examines ideal femoral head screw trajectory and measures resulting femoral anteversion via angles relative to the distal femur posterior condylar tangent line. In 30 femurs, PF entry shows a significantly greater retroversion difference, averaging about 16°.",{"@graph":69,"@context":126},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":35,"@type":76,"position":81},"https://docshare.wps.com/document/healthcare/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/espinoza-technique-leads-to-excessive-retroversion-in-piriformis-fossa-entry-nailing-computed-tomographic-analysis/435497/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/espinoza-technique-leads-to-excessive-retroversion-in-piriformis-fossa-entry-nailing-computed-tomographic-analysis/435497.png","ImageObject",300,407,{"name":92,"@type":93},"awa","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-09-30","2026-09-29",true,{"@type":102,"interactionType":103,"userInteractionCount":14},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118,122],{"name":109,"@type":110,"acceptedAnswer":111},"What question does the study address?","Question",{"text":112,"@type":113},"It evaluates whether the Espinoza technique yields equally reliable femoral rotational alignment when using piriformis fossa versus greater trochanter entry during antegrade femoral intramedullary nailing.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How was femoral rotation measured in this research?",{"text":117,"@type":113},"The study mapped the ideal femoral head screw trajectory by aligning PF and GT entry points to the femoral head center, then measured the angle between reference lines and the distal femur posterior condylar tangent line to derive resultant anteversion.",{"name":119,"@type":110,"acceptedAnswer":120},"What did the results show about PF versus GT entry?",{"text":121,"@type":113},"Using PF entry produced additional unplanned retroversion compared with GT entry, with a mean rotational difference of about 15.8° and statistical significance (P \u003C 0.001).",{"name":123,"@type":110,"acceptedAnswer":124},"What is the study’s recommendation?",{"text":125,"@type":113},"PF entry nailing with the Espinoza technique may increase postoperative retroversion, so the technique may need restriction to GT entry to prevent fracture malrotation.","https://schema.org",{"og:url":83,"og:type":128,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":130,"canonical":83},"index,follow",{"doc_id":132,"site_id":62},435497,1790741902,{"code":4,"msg":5,"data":135},{"doc_id":132,"user_id":136,"nickname":92,"user_avatar":137,"doc_module":4,"category_id":34,"category_name":35,"doc_title":65,"doc_description":67,"doc_content":138,"file_id":139,"file_url":140,"file_type":141,"file_size":142,"view_count":14,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":19,"language":143,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":144,"faqs":145,"seo_title":146,"seo_description":67,"update_tm":147,"read_time":52},3985747858093,"https://ap-avatar.wpscdn.com/davatar_3d24733baf745e90a7e4bdd5f77d97b2","Clinical/Basic Science Research Article  \nEspinoza technique leads to excessive retroversion in piriformis fossa entry nailing: computed tomographic analysis  \nMonica Guirgus, MBSa , Bradley A. Carlson, MD, MBAb , Damien Cannon, MDb , Walter Virkus, MDc , Jason Y. Chen, MDb  \nObjectives: To evaluate whether aligning femoral rotation utilizing the intramedullary nail’s inherent anteversion during antegrade femoral intramedullary nailing (Espinoza technique) is equally reliable through piriformis fossa (PF) and greater trochanter (GT) entry portals.  \nDesign: Retrospective computed tomography analysis.  \nSetting: Level I Trauma Center.  \nPatients/Participants: Adult patients without prior femur fractures or congenital femoral abnormalities and with prior computed tomography scans of the entire femur for indications unrelated to fractures.  \nIntervention: Ideal femoral head screw trajectory was mapped by aligning the PFand GT entry points with the center of the femoral head. The angle between these lines and the distal femur posterior condylar tangent line was measured to demonstrate resultant femoral anteversion.  \nMain Outcome Measure: The difference between these angles was compared to show the difference in femoral version between PF and GT entry nailing using the Espinoza technique to assess rotational fracture alignment.  \nResults: Thirty femurs from 15 uninjured patients were evaluated. Mean rotational difference between GT and PF entry points was 15.8° 6 5.6° of additional retroversion with the PF entry point (P , 0.001) .  \nConclusions: During PF entry nailing, application of the Espinoza technique can lead to an additional unplanned average of 16° of postoperative femoral retroversion due to the relatively posterior and medial location of the PF entry point. Use of the Espinoza technique may need to be restricted to GT entry nailing to prevent fracture malrotation.  \nKeywords: Espinoza technique, malrotation, femoral shaft fractures, subtrochanteric femur fractures, piriformis fossa, greater trochanter, intramedullary nailing, rotational deformity  \n1. Introduction  \nIntramedullary nailing of femoral shaft and subtrochanteric femur fractures is a common procedure for orthopaedic surgeons. Fixation can be complicated by rotational malreduction. Various  \nW. Virkus—Connextions: Stock or stock Options, GLW, Inc: Stock or stock Options, Johnson and Johnson: Stock or stock Options, Norvartis: Stock or stock Options, Novartis: Employee, Olio, Inc: Stock or stock Options, SLACK Incorporated: Publishing royalties, financial or material support, Stryker: Paid consultant; Stock or stock Options. The remaining authors have no conflicts of interest to disclose. a California University of Science and Medicine, Colton, CA, b Department of Orthopeadic Surgery, Loma Linda University Health, Loma Linda, CA, c Department of Orthopeadic Surgery, Indiana University School of Medicine, Indianapolis, IN.  \n*Corresponding author. Address: 25455 Barton Road, Suite 102B, Loma Linda, CA [92354. E-mail address: BACarlson001@gmail.com](92354. E-mail address: BACarlson001@gmail.com) (B. Carlson).  \nSource of funding: Nil.  \nCopyright © 2026 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Orthopaedic Trauma Association.  \nThis is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal.  \nOTAI (2026) e462  \nReceived: 10 December 2024 / Accepted: 26 November 2025  \nPublished online 6 January 2025  \n[http://dx.doi.org/10.1097/OI9.0000000000000462](http://dx.doi.org/10.1097/OI9.0000000000000462)  \nmethods have been described to address intraoperative rotational reduction, including the cortical step sign and lesser trochanter profile, with variable results and limited","cbCaipqfxA8Y7Tfn","https://ap.wps.com/l/cbCaipqfxA8Y7Tfn","pdf",561204,"English","# Introduction\n# Methods","[{\"question\":\"What question does the study address?\",\"answer\":\"It evaluates whether the Espinoza technique yields equally reliable femoral rotational alignment when using piriformis fossa versus greater trochanter entry during antegrade femoral intramedullary nailing.\"},{\"question\":\"How was femoral rotation measured in this research?\",\"answer\":\"The study mapped the ideal femoral head screw trajectory by aligning PF and GT entry points to the femoral head center, then measured the angle between reference lines and the distal femur posterior condylar tangent line to derive resultant anteversion.\"},{\"question\":\"What did the results show about PF versus GT entry?\",\"answer\":\"Using PF entry produced additional unplanned retroversion compared with GT entry, with a mean rotational difference of about 15.8° and statistical significance (P \\u003c 0.001).\"},{\"question\":\"What is the study’s recommendation?\",\"answer\":\"PF entry nailing with the Espinoza technique may increase postoperative retroversion, so the technique may need restriction to GT entry to prevent fracture malrotation.\"}]","Espinoza technique leads to excessive retroversion in piriformis fossa entry nailing - computed tomographic analysis | PDF",1790673881]