Short Abstracts

LowEnergy Occult Femoral and Pelvic Fractures in the Elderly

Authors: {'first_name': 'Thomas', 'last_name': 'Kirchgesner'},{'first_name': 'Souad', 'last_name': 'Acid'},{'first_name': 'Fr\xc3\xa9d\xc3\xa9ric', 'last_name': 'Lecouvet'},{'first_name': 'Bruno', 'last_name': 'Vande Berg'}


Proximal femoral fractures and pelvic fractures are common in elderly patients with a dramatic increase expected in the next decades due to population aging. Early detection of such fractures is crucial for optimal patient management and cost containment, especially in proximal femoral fractures. Most fractures are detected on conventional radiographs, but some fractures are occult (i.e. not radiographically detectable) [1]. Magnetic resonance imaging (MRI) is the gold standard second-line imaging modality to detect occult post-traumatic injuries with acquisition protocols including fat-sensitive and/or fluid-sensitive images [2]. Computed tomography (CT) is a valuable second-line imaging modality to perform rapid and efficient patient’s triage in the emergency department (Figure 1) [3].

Keywords: occultfracturefemurpelvisCTMRIelderly 
 Accepted on 10 Sep 2021            Submitted on 02 Sep 2021
Figure 1 

Radiographically occult fracture of the right proximal femur in an 86-year-old female patient admitted to the emergency department after low-energy trauma. (a) Radiographs of the right hip and pelvis performed the day of the trauma did not demonstrate any fracture. The patient was included in a research study and imaged at both MRI and CT that same day. MRI of the pelvis demonstrated a poorly defined medullary area in the right greater trochanter (arrow) with decreased signal intensity on the (b) spin-echo T1-weighted sequence and (c) fat-only T2-weighted Dixon images and increased signal intensity on the (d) Short Tau Inversion Recovery (STIR) sequence and (e) water-only T2-weighted Dixon images. A central linear low signal intensity area on the fluid-sensitive images was suggestive of a trabecular fracture (arrowhead), but no cortical interruption was seen. (f) Bone kernel multiplanar reconstructions (MPR) and (g) Maximum Intensity Projection (MIP) reconstructions of the pelvic CT demonstrated the cortical bone interruption (arrow) that was not visible at MRI. (h) Soft tissue kernel MPR also demonstrated the “bone marrow edema” of the right greater trochanter (arrow).

Competing Interests

The authors have no competing interests to declare.


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