How to measure bone age
May 20, 2025
Source: Cainiu Health
Dr. Chen Jian
Introduction
Bone age can be assessed through methods such as wrist X-ray examination, knee joint X-ray examination, ultrasound bone age testing, computed tomography (CT) for bone age assessment, and magnetic resonance imaging (MRI) for bone age evaluation. To ensure accuracy and safety of the results, it is important to choose a qualified hospital for these assessments. During X-ray examinations, care should be taken to protect areas such as the eyes and thyroid gland from radiation exposure.
Generally, bone age can be assessed through methods such as X-ray examination of the wrist, X-ray examination of the knee joint, ultrasound bone age testing, computed tomography (CT) for bone age assessment, and magnetic resonance imaging (MRI) for bone age assessment. The specific details are as follows:
1. Wrist X-ray Examination: The wrist contains multiple long bones, short bones, and carpal bones. The developmental status of these bones can effectively reflect the overall skeletal development level of the body. During childhood and adolescence, the epiphyses appear, grow, and fuse in a certain sequence and timeframe. Taking an X-ray of the wrist allows clear visualization of the shape, size of the epiphyses, and their degree of fusion with the diaphyses, thereby enabling assessment of bone age.
2. Knee Joint X-ray Examination: The knee joint is a major weight-bearing joint in the human body, and changes in epiphyseal development are important references for bone age evaluation. The distal femoral, proximal tibial, and proximal fibular epiphyses undergo regular changes during growth and development. By observing the developmental stage of these epiphyses, bone age can be estimated.
3. Ultrasound Bone Age Testing: Ultrasound technology can measure certain physical properties of bones, such as bone density and cortical bone thickness. These physical characteristics change with age during a child's growth and development. Using an ultrasound probe to detect ultrasound signals between the epiphyses and diaphyses, and analyzing the characteristics of these signals, bone age can be inferred.
4. Computed Tomography (CT) for Bone Age Assessment: CT scanning provides three-dimensional structural information of bones, enabling more detailed observation of the morphology, internal structure of epiphyses, and their relationships with surrounding tissues. By analyzing multiplanar images of the bones, including cross-sectional, sagittal, and coronal views, and using computer software algorithms, bone age can be determined.
5. Magnetic Resonance Imaging (MRI) for Bone Age Assessment: MRI can clearly display the anatomical structures and signal characteristics of bones, epiphyseal cartilage, and surrounding soft tissues. By observing changes in the thickness and signal intensity of epiphyseal cartilage, as well as the relationship between the epiphysis and diaphysis, bone age can be inferred.
Bone age assessment should be conducted at a qualified medical facility to ensure accuracy and safety of the results. During X-ray examinations, protective measures should be taken to shield areas such as the eyes and thyroid gland from radiation exposure.
