Dual Energy CT – a Novel Technique for Diagnostic Testing of Fragility Fractures of the Pelvis

Abstract

The incidence of fragility fractures of the pelvis is increasing. Established methods to diagnose this condition include X-rays, computed tomography (CT) and magnetic resonance imaging (MRI). Dual energy CT (DECT) is a modern technology for the imaging of bone oedema/bruises and has been used in injuries of the extremities and spine. It is unclear whether this technique can also be used in fragility fractures of the pelvis. The aim of this study was to perform a literature research and survey of the "AG Becken III" members of the German Society of Trauma Surgery (DGU) on the usefulness of DECT in fractures of the pelvis. A PubMed-based literature search on DECT comprised the key words "Dual Energy CT", "Pelvis/Pelvic", "Insufficiency" and "Fractures" and their combinations. Thirty-two publications were reviewed completely (full text). Finally, 15 articles were chosen and included in the current study. The survey of the members of the "AG Becken III" was based on a questionnaire and aimed to determine the popularity and potential benefits of DECT in comparison to established diagnostic options. No studies on the use of DECT in fragility fractures of the pelvis were identified; the few articles found referred to fractures of the extremities and spine. The response rate to the questionnaire was 25/83 (30.1 %). The participants had a mean personal experience of 8.4 years/151.6 interventions in pelvic surgery. Although some respondents had heard of DECT, this technique - if available - was only used in other indications. However, the potential benefit of DECT was recognised, especially in the acute diagnostic testing of fragility fractures. There is limited consensus on the optimal diagnostic test (CT vs. MRI) of pelvic fractures. Although DECT is already established for other indications and is regarded as a promising method by all respondents of the "AG Becken III", DECT is not yet routinely used for diagnostic testing of fragility fractures of the pelvis. Potential advantages of DECT include its greater sensitivity than CT in detecting bone oedema with equal radiation exposure. Unlike MRI, it is available 24 hours/7 days.

Modified Therapy Concepts for Fragility Fractures of the Pelvis after additional MRI

“…Predictions for the year 2030 suggested an increase by 200% [11]. In the evaluations of the Pelvic Injury Register of the German Trauma Society with 13,300 pelvic fractures, a shift in the average age of onset of the disease from 52 years in 2004 to 67 years in 2016 could be seen [12]. In the USA, 7% of osteoporosis-associated fractures were insufficiency fractures of the pelvis over the age of 50; with a share of 5% of the total treatment costs, they have a high socio-economic relevance [13].…”

“…In severely injured patients with adequate pelvic trauma, diagnosis is clearly defined by the S3 guideline polytrauma [22]. In contrast, the diagnostic procedure for insufficiency fractures has not yet been conclusively clarified: An equivalent priority of MRT and Dual Energy CT (DECT) is described [12,23]. In a current study, 25 experts of the Pelvic Injury Register of the German Trauma Society were asked about the significance of the above-mentioned diagnostic procedures for the detection of FFP:…”

Dual Energy Computed Tomography in Musculoskeletal Imaging, with Focus on Fragility Fractures of the Pelvis

“…Dies liegt zum einen an der noch fehlenden Verfügbarkeit, da diese Scan- nertypen nicht flächendeckend zur Verfügung stehen, zum anderen aber auch am mangelnden Bekanntheitsgrad der sich bietenden Möglichkeiten. In einer kürzlich veröffentlichten Studie unserer Arbeitsgruppe, bei der wir den Expertenkreis der AG Becken III der Deutschen Gesellschaft für Unfallchirurgie hinsichtlich Bekanntheitsgrad und Verfügbarkeit der DECT befragt haben, zeigte sich, dass etwa 2 2 ⁄3 3 der Befragten die Dual-Energy-Technik zwar kennen, sie aber trotzdem nur begrenzt Anwendung findet [9].…”

“…Während bei akuten Verletzungen mit adäquatem Trauma die konventionelle CT die etablierte Bildgebungsmodalität der Wahl sowohl zur Diagnostik als auch zur Frakturklassifikation und damit Entscheidungsgrundlage zum therapeutischen Vorgehen darstellt, da hier die Frakturlinien gut nachgewiesen werden können, ist dies bei Insuffizienzfrakturen des Beckens z. T. nicht so einfach möglich [9]. Frakturlinien im Rahmen von "fragility fractures" in osteoporotischer Knochenstruktur können in der CT nämlich dem Nachweis entgehen oder zeigen nur "die Spitze vom Eisberg".…”

“…Als die sensitivste Untersuchungsmodalität zur Diagnose von Knochenmarködemveränderungen als Zeichen einer Insuffizienzfraktur gilt dabei schon seit längerer Zeit [10] die Magnetresonanztomografie (MRT), die jedoch auch in großen Zentren für diese Fragestellung nur bedingt zur Verfügung steht, insbesondere nicht 24 Stunden/7 Tage. Die Dual-Energy-CT könnte hier eine schnelle und robuste Alternative zum MRT darstellen und zur Verbesserung der Diagnostik beitragen [9].…”