Moriarty Meghan A, Stefanov Dimitri G, Brown Michael S, Walz Daniel M, Walsh Pamela J
Department of Radiology, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Health, Manhasset, NY, USA.
Department of Biostatistics, Academic Affairs, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA.
Emerg Radiol. 2025 Feb;32(1):13-22. doi: 10.1007/s10140-024-02293-3. Epub 2024 Oct 25.
To determine if difference in Hounsfield Units (HU) of the medullary bone between the injured and non-injured femurs in patients with greater trochanteric fractures is associated with occult intertrochanteric (IT) extension.
Retrospective review was performed of 81 patients (age range 54-102, 54 females and 27 males) who underwent CT and subsequent MRI after identification of a greater trochanteric fracture without evidence of IT extension on radiography and/or CT. Hounsfield units of the injured and non-injured femurs on CT were recorded at the level of the base of the greater trochanter centrally (ROI1) and the level of the upper border of the lesser trochanter posteromedially (ROI2). The difference between the injured and non-injured femur for each ROI1 and ROI2 were calculated. Absence or presence, and if present, extent of IT extension was assessed on MRI. Analysis was performed to determine if there is correlation of difference in density with presence, and extent of occult IT fractures.
81 cases met inclusion criteria, 14 (17%) had no IT extension, 11 (14%) had less than 50% IT extension and 56 (69%) had 50% or greater IT extension. There was statistical significance between presence and absence of IT extension between the injured and non-injured femur for ROI1 (HU) no IT extension median (IQR): 18.8(4-40), ROI1 (HU) present IT extension median (IQR): 65.5(46-90) p < .0001, and for ROI2 no IT extension median (IQR): 3(-8-25.5) and ROI2 present IT extension 51(40.5-76), p < .0001. There was statistical significance of the extent of IT extension: ROI1 less than 50% IT extension median (IQR): 37.5(27.5-57), ROI1 50% or greater IT extension median (IQR): 72.3(53.5-91.3), p < .0001, and for ROI2 less than 50% IT extension median (IQR): 17.5(8-49), and ROI2 50% or greater IT extension median (IQR): 55.8(45.3-81.5), p < .0001. A threshold ROI2 difference of 50 HU resulted in specificity of 92% and sensitivity 60.7% of for IT extension 50% or greater.
Patients presenting with greater trochanteric fractures, an asymmetric increased density measured by ROI differences within the medullary space of the IT region between the injured and non-injured femur is associated with occult IT extension.
确定大转子骨折患者受伤侧与未受伤侧股骨髓质骨的亨氏单位（HU）差异是否与隐匿性转子间（IT）延伸有关。
对81例患者（年龄范围54 - 102岁，54例女性和27例男性）进行回顾性研究，这些患者在X线摄影和/或CT检查未发现IT延伸证据后接受了CT及后续MRI检查。在大转子基部中心层面（ROI1）和小转子后内侧上缘层面（ROI2）记录受伤侧与未受伤侧股骨的CT亨氏单位。计算每个ROI1和ROI2中受伤侧与未受伤侧股骨的差异。通过MRI评估IT延伸的有无，若存在则评估其范围。进行分析以确定密度差异与隐匿性IT骨折的存在及范围是否相关。
81例符合纳入标准，14例（17%）无IT延伸，11例（14%）IT延伸小于50%，56例（69%）IT延伸50%或更大。ROI1中受伤侧与未受伤侧股骨IT延伸存在与否之间有统计学意义（HU）：无IT延伸中位数（IQR）：18.8（4 - 40），有IT延伸中位数（IQR）：65.5（46 - 90），p <.0001；ROI2中无IT延伸中位数（IQR）：3（-8 - 25.5），有IT延伸中位数（IQR）：51（40.5 - 76），p <.0001。IT延伸范围有统计学意义：ROI1中IT延伸小于50%中位数（IQR）：37.5（27.5 - 57），IT延伸50%或更大中位数（IQR）：72.3（53.5 - 91.3），p <.0001；ROI2中IT延伸小于50%中位数（IQR）：17.5（8 - 49），IT延伸50%或更大中位数（IQR）：55.8（45.3 - 81.5），p <.0001。ROI2差异阈值为50 HU时，IT延伸50%或更大的特异性为92%，敏感性为60.7%。
对于出现大转子骨折的患者，受伤侧与未受伤侧股骨IT区域髓腔内通过ROI差异测量的不对称密度增加与隐匿性IT延伸有关。
