Bone Abstracts

Purpose: There is no agreed standardised method for assessing vertebral morphology. The algorithm-based qualitative technique appears to be promising in adults to rule out non-osteoporotic fractures and non-fracture deformities, however it has not been previously trialled in children. We aim to modify a technique for use with both dual energy X-ray absorptiometry and radiographs in children, and to evaluate its reliability and reproducibility.

Methods: 50 patients with a suspected reduction in bone density, having a lateral spine radiograph and lateral dual energy X-ray absorptiometry on the same day, between the ages of 5–15 years, were recruited prospectively.

Three observers have independently assed all images (blinded to corresponding results of radiographs and dual energy X-ray absorptiometry) using the modified algorithm-based qualitative criteria. A consensus read was performed by the observers simultaneously to act as a gold standard for sensitivity and specificity assessment. Inter-observer and modality agreement of fracture detection and characteristics have been assessed.

Interim results using the modified algorithm-based qualitative criteria had limitations. It was useful for fracture detection, severity grading and shape analysis, but not for endplate or position assessment. A survey was sent to 14 British Paediatric and Adolescent Bone Group members to assess the clinical relevance of the criteria; 13 responded. Following consultation simplifications were made.

The images will be re-assed after an interval of 3 months using the new modified algorithm-based qualitative criteria and the data analysed as before. The reliability of the two techniques will be compared.

Results: Analysis with the original modified algorithm-based qualitative technique showed 26 patients had one or more vertebral fractures. The inter-observer agreement for fracture detection, severity grading, shape analysis, end plates affected and position analysis on dual energy X-ray absorptiometry ranged between 68 and 78% and on radiographs between 66 and 77%. Analysis using the second scoring system is in progress.

Conclusion: The modified algorithm-based qualitative assessment had limitations. We have further modified the scoring system to allow standardisation of readers’ observations and note only findings of clinical relevance. We are currently evaluating the new system and comparing its reliability to the previous technique.