Clinical History, Examination and Blood Test Results

  • This lady had an unexplained leg length discrepancy

  • A long leg radiograph was obtained however it was hard to find the exact location of the discrepancy

  • EOS scanning was used to get an accurate measurement of the leg length, taking into account pelvic tilt, to assess the cause of the problem

  • EOS imaging takes a simultaneous low dose AP and lateral radiographs with the patient in a functional position. 3D measurements can then be taken from the image which take into account pelvic tilt, posture and flexion in the hip, knee and ankle

Imaging results


Click on the image for a closer look



Click on the image for a closer look

The measurements taken from the EOS scan calculate the absolute leg length discrepancy taking into account for the pelvic tilt of the patient while they are standing in a functional position. This is not possible with a long leg radiograph. The red boxes highlight the length discrepancies; the L tibia is 2mm longer than the R tibia; the L femur is 9mm longer than the R femur. The red lines highlight buttock crease, showing the functional discrepancy. Overall there is an LLD of 11mm

A long leg radiograph demonstrates a longer left femur, however it is hard to accurately quantify the increase in length from this image

Learning Points

  • EOS imaging allows for a functional leg length discrepancy to be calculated. This can then assist in the surgical planning of correcting this discrepancy.