Overview of Skeletal Dysplasia (SD)
Skeletal dysplasia (SD) is a hereditary disease that affects the composition and structure of bone and cartilage tissues, and is characterized by various types of abnormalities in the growth and development of skeletal tissues, such as short stature, misalignment of joints, deformities of the head and limbs, abnormal curvature of the spine, and changes in bone mineral density, sometimes in combination with other systemic malformations. 1986, Stoll et al. reported the prevalence of SD at birth to be about 3/10,000 by statistical epidemiological analysis and summarization of previous studies, and suggested that ultrasonography is a feasible method for prenatal diagnosis. In 1986, Stoll et al. reported that the birth prevalence of SD was about 3/10,000 through statistical analysis of epidemiology and summarization of previous studies, and suggested that ultrasonography was a feasible method for prenatal diagnosis.
Causes
The main cause of skeletal dysplasia is genetic, through autosomal recessive inheritance, autosomal dominant inheritance, X-linked recessive inheritance, X-linked dominant inheritance, germline chimerism and uniparental diploidy.
Symptoms
Patients are often complicated by skeletal deformities in different parts of the body, and the clinical phenotype varies, with chondrodysplasia and osteogenesis imperfecta being the most common types. The most common symptoms are short stature, misalignment of joints, deformities of the head and limbs, abnormal curvature of the spine, and changes in bone density. The condition is sometimes mild or can be so severe that spontaneous abortion occurs before birth. However, most of the time, the disease develops rapidly and severely during the developmental stage and is combined with other organ dysfunctions. Currently, SD is classified into 436 types and 42 categories according to its known molecular genetic basis, etiology, and phenotype, including collagen dysplasia (Stickler syndrome, Weissenbacher, Zwey, and muller syndrome), epiphyseal dysplasia, osteogenesis imperfecta, and decreased bone mineral density, lysosomal storage dysplasia (mucopolysaccharidosis), and human fibroblast growth factor receptor 3 (HFGFR3). Fibroblast growth factor receptor 3 (FGFR3) gene-related chondrodysplasia is the most common type.
Screening
In addition to the evaluation of clinical symptoms, imaging tests such as X-ray (commonly used for preliminary observation of long bones, hands, feet, skull, chest, vertebrae, and pelvis), magnetic resonance imaging (MRI), and computed tomography (CT) scanning are also used to assist in the diagnosis of chondrodysplasia. In addition, depending on the type of disease, genetic tests such as whole exome sequencing (WES) may be performed.
Diagnosis
The initial diagnosis is based on the symptoms and the results of imaging studies. In addition, depending on the type of disease, genetic tests such as Whole Exome Sequencing (WES) can be performed.
Treatment
There is no specific treatment for this disease, but surgical interventions (e.g., artificial hip joints) have proven effective in some non-fatal types.
Prognosis
Although some types of skeletal dysplasia are fatal, the cause of death in these types of SD is pulmonary dysfunction due to thoracic dysplasia, and hearing and visual impairment can also be seen. However, patients with generalized skeletal dysplasia usually have a normal life expectancy.