Changes

[[File:Femoral offset in hemiarthroplasty(crop).jpg|thumb|170px|Femoral offset in hemiarthroplasty.<ref name="JonesBriffa2017">{{cite journal|last1=Jones|first1=Carl|last2=Briffa|first2=Nikolai|last3=Jacob|first3=Joshua|last4=Hargrove|first4=Richard|title=The Dislocated Hip Hemiarthroplasty: Current Concepts of Etiological factors and Management|journal=The Open Orthopaedics Journal|volume=11|issue=Suppl-7, M4|year=2017|pages=1200–1212|issn=1874-3250|doi=10.2174/1874325001711011200}}</ref>.]] The main measure after hemiarthroplasty is femoral (neck) offset, which is defined as the perpendicular distance between the intramedullary or longitudinal axis of the femur and the center of rotation of the native or prosthetic femoral head. <ref name="JonesBriffa2017"/> An unnatural offset, as compared to the contralateral side, of less than 33 mm is associated with hip dislocation.<ref name="JonesBriffa2017NinhSethi2009">{{cite journal|last1=Ninh|first1=Christopher C.|last2=Sethi|first2=Anil|last3=Hatahet|first3=Mohammed|last4=Les|first4=Clifford|last5=Morandi|first5=Massimo|last6=Vaidya|first6=Rahul|title=Hip Dislocation After Modular Unipolar Hemiarthroplasty|journal=The Journal of Arthroplasty|volume=24|issue=5|year=2009|pages=768–774|issn=08835403|doi=10.1016/j.arth.2008.02.019}}</ref>