Review and optimisation of foot radiography technique

Radiography is an important tool in the diagnosis of trauma and diseases of the foot. Consistent image quality and anatomical appearances are essential to ensure that images are interpreted correctly and this study aims to evaluate current technique and use anthropomorphical phantoms in order to investigate the most optimal radiographic technique.

A two part study was conducted. An electronic survey was administered in order to ascertain the current radiographic technique utilised within the United Kingdom (UK) National Health Service (NHS) and compare this with techniques published within radiographic positioning textbooks in common use within the UK. A phantom experiment also sought to identify the most appropriate angulation of the central beam to employ in order to optimally visualise the anatomy for standard non-trauma radiography of the foot. A relative visual grading analysis technique was used to assess radiographic quality.

The electronic survey was completed by 38% of departments (n = 69/182) and demonstrated wide inconsistencies in projections, centring points and beam angulations employed across the NHS. The most commonly employed techniques no longer match the majority of positions described in textbooks. The phantom experiment modelled the ability to accurately visualise anatomy with a variation of the central beam angulation. The results demonstrated that the most commonly described textbook techniques remain the most optimal for accurately visualising the anatomy of the foot.

This study has validated the radiographic techniques of the foot described in many of the key texts, however self-reported current practice has diverged from this textbook description.

Reinforcement of fundamental principles will benefit the patient with increased image quality, improved diagnosis and improved consistency of images, particularly when patient care is transferred between centres.