Standardization of Weightage Assigned to Different Segments of the Hand X-ray for Assessment of Bone Age by the Greulich-Pyle Method.

Introduction: Bone age (BA) assessment is important in evaluating disorders of growth and puberty; the Greulich and Pyle atlas method (GP) is most used. We aimed to determine the weightage to be attributed by raters to various segments of the hand x-ray, namely, distal end of radius-ulna (RU), carpals, and short bones for rating bone age using the GP atlas method. Methods: 692 deidentified x-rays from a previous study (PUNE-dataset) and 400 from the Radiological Society of North America (RSNA-dataset) were included in the study. Mean of BA assessed by experienced raters was termed reference rating. Linear regression was used to model reference age as function of age ratings of the three segments. The root-mean-square-error (RMSE) of segmental arithmetic mean and weighted mean with respect to reference rating were computed for both datasets. Results: Short bones were assigned the highest weightage. Carpals were assigned higher weightage in pre-pubertal PUNE participants as compared to RSNA, vice-versa in RU segment of post-pubertal participants. The RMSE of weighted mean ratings was significantly lower than for the arithmetic mean in the PUNE dataset. Conclusion: We thus determined weightage to be attributed by raters to segments of the hand x-ray for assessment of bone age by the GP method.

The automated Greulich and Pyle: a coming-of-age for segmental methods?

The well-known Greulich and Pyle (GP) method of bone age assessment (BAA) relies on comparing a hand X-ray against templates of discrete maturity classes collected in an atlas. Automated methods have recently shown great success with BAA, especially using deep learning. In this perspective, we first review the success and limitations of various automated BAA methods. We then offer a novel hypothesis: When networks predict bone age that is not aligned with a GP reference class, it is not simply statistical error (although there is that as well); they are picking up nuances in the hand X-ray that lie "outside that class." In other words, trained networks predict distributions around classes. This raises a natural question: How can we further understand the reasons for a prediction to deviate from the nominal class age? We claim that segmental aging, that is, ratings based on characteristic bone groups can be used to qualify predictions. This so-called segmental GP method has excellent properties: It can not only help identify differential maturity in the hand but also provide a systematic way to extend the use of the current GP atlas to various other populations.

Safety and Efficacy of Bilateral Epiphysiodesis Surgery to Reduce Final Height in Extremely Tall Adolescents - A Follow-up Study.

INTRODUCTION: Treatment options in patients with extreme tall stature are limited. Bilateral epiphysiodesis has emerged as a possible treatment method aiming to reduce final height. However, there is still insufficient data on long-term safety and final height outcome. Therefore, the aim of this study was to assess the efficacy and safety of bilateral epiphysiodesis to reduce final adult height in tall adolescents. METHODS: The study population consisted of 72 patients with extreme tall stature who were followed at the Pediatric Endocrine Clinic at the Karolinska University Hospital, Stockholm (Sweden) and subsequently underwent bilateral epiphysiodesis around the knees (girls n=45, boys n=27). RESULTS: When compared to the final height prediction at time of surgery, the procedure significantly reduced the achieved final height by a mean of 3.6 cm ± 0.4 cm in girls (p<0.001; 26.0 ± 2.9 % reduction) and 8.6 ± 0.9 cm in boys (p<0.001; 40.5 ± 3.0 % reduction). Furthermore, a negative correlation was observed between the absolute height reduction and the bone age at time of surgery, which was stronger in boys (r=-0.63, p<0.001) than in girls (r=-0.44, p<0.001). Besides reducing final height, body proportions were affected in all patients subjected to bilateral epihyseodesis. However, as tall individuals typically have relatively long legs, body proportions were rather normalized after the surgery. There were no serious complications reported. CONCLUSION: This study suggests that bilateral epiphysiodesis is an efficient and safe method to reduce final height in extremely tall adolescent girls and boys. The achieved height reduction was higher in boys and when performed at an earlier bone age. Importantly, no serious side-effects were reported. However, a continued follow-up is still warranted to detect any potential rare complications.