The Risser sign was measured according to both the United States and European grading systems. Digital skeletal age was calculated, and triradiate cartilage ossification was assessed.
根据美国和欧洲的分级系统测量标志的里塞尔，计算数字骨龄，评估软骨骨化。
2
A new system with three groups was tested, and the second group (Risser 0 with closed triradiate cartilage and Risser 1) was the best predictor of a digital skeletal age score of between 400 and 425.