Femoroacetabular impingement (FAI) is increasingly being recognised as a cause for hip pain in the young, mobile patient group. A complex, evolving clinical area, FAI has recently been considered by an international panel to try and achieve consensus regarding diagnosis, management and terminology (1). The Warwick Agreement defines FAI as “ a motion-related clinical disorder of the hip with a triad of symptoms, clinical signs and imaging findings. It represents symptomatic premature contact between the proximal femur and the acetabulum”(1). Typically, the imaging component of...

43 consecutive patients (16 patients undergoing standard pelvic CT and 27 patients undergoing the low dose CT protocol), with an average age of 34.8 years (range- 17-63 years), investigated for FAI between March 2015 to January 2017 using the institution's radiology information system. Multiple dose parameters were recorded including CTDIvol, DLP,mAs and kV. The effective dose (mSv) was calculated using standard methods (conversion factor 0.019 (2)) and compared.

The mean mAs was reduced from 117.0 (range: 20-156) to 76.6 (range: 45-150) using the limited scan range protocol. The kV was 118.6 (range: 100-135) in the standard protocol group and 100.7 (range: 100-120) in the low dose group. The mean DLP (mGy-cm) using the standard protocol was 278.6 (range: 152.4- 736.7; standard error 34.1, n=16), compared to 72.5 (range: 35.8- 145.4; standard error 6.3, n=27) for the low dose protocol (two sample t-test, p < 0.001). The mean effective dose (mSv) was reduced by...

CT permits better assessment of femoroacetabular morphology compared to plain film imaging and is useful in directing surgical intervention where this is being considered (1). However, it is important that strategies to ensure as low as reasonably practicable radiation doses are employed since FAI is typically seen in the young population. In our study the average patient was 35 years old. At our institution, practice has been modified so that rather than whole pelvic CT, the scan range is restricted to the region of interest...

1. The Warwick Agreement on femoroacetabular impingement syndrome (FAI syndrome): an international consensus statement. Griffin DR,Dickenson EJ,O'Donnell J,Agricola R,Awan T,Beck M,Clohisy JC,Dijkstra HP,Falvey E,Gimpel M,Hinman RS,Hölmich P,Kassarjian A,Martin HD,Martin R,Mather RC,Philippon MJ,Reiman MP,Takla A,Thorborg K,Walker S,Weir A,Bennell KL. Br J Sports Med.2016 Oct; 50(19): 1169-76. 2. Estimating Effective Dose for CT Using Dose–Length Product Compared With Using Organ Doses: Consequences of Adopting International Commission on Radiological Protection Publication 103 or Dual-Energy Scanning. Christner JA, Kofler JM, McCollough CH. AJR. 2010; 194: 881-889. 3. Public Health...

M.A. Shah Department of Radiology St. James Wing St George’s University Hospitals NHS Foundation Trust Blackshaw Road Tooting London SW17 0QT [email protected]