Background: Bone age studies require X-ray of the left hand and wrist to assess skeletal maturity. The Tanner-Whitehouse 3 (TW3) scoring method provides an objective framework for calculating bone age and specifies exact placement of the hand. In our service we have noted a number of poor quality films, caused by difficulty with hand placement, e.g. scrunching of the fingers. This compromises the ability to score accurately and in a proportion necessitates re-X-ray, with time, financial and radiation exposure consequences.
Aim: To assess X-ray quality and need for re-X-ray in patients having TW3 bone ages.
Method: We performed a prospective study of all bone age X-rays conducted at Sheffield Childrens Hospital from May 2013 to February 2014. The quality of bone age X-rays was rated by a single specialist Auxology Nurse. The position of the thumb, fingers and the overall clarity of the X-ray were scored on a simple 13 scale (poor, adequate, good), generating a score out of 9. The need for re-X-ray was noted.
Results: Of the 259 bone ages studied, from patients aged 1.92 to 18.48 years, 123 were females. There were 12 X-rays scoring 1 (4.63%) (poor quality) for both the finger and thumb positions and nine for X-ray clarity (3.47%). The number of studies scoring <3 for position of fingers, thumb and overall clarity was 38 (14.67%), 26 (10.04%) and 77 (29.73%) respectively. The number of re-X-rays required was 28 (10.81%).
Discussion: We have shown that achieving good quality films on which to assess bone age may be more difficult than presumed. We believe the re-X-ray rate to be unnecessarily high and have devised a simple hand outline template, placed on the X-ray plate, to encourage the correct positioning of the hand. We are currently evaluating its efficacy using the same scoring system.
12 - 14 Nov 2014
British Society for Paediatric Endocrinology and Diabetes