Due to the kyphoscoliosis, the trunk appears short in later childhood. Clubfoot can be present. Adult height is between 100-145cm. It is important for individuals with Kniest dysplasia to have their cervical or neck vertebra followed with careful neurologic exams, x-rays of the neck in flexion and extension, and MRIs if warranted. Coronal clefts of the lumbar vertebrae may be seen.
Kniest dysplasia is inherited in an autosomal dominant manner.
Prenatal diagnosis has been made by second trimester ultrasound. The main conditions to distinguish from Kniest dysplasia are SEDc, Kniest-like dysplasias, and metatropic dysplasia. Lung Hypoplasia and Severe Pulmonary Hypertensionin an Infant with Double Heterozygosity for Spondyloepiphyseal Dysplasia Congenita and Achondroplasia. Horton, W.A., et. Growth Curves for Height for Diastrophic Dysplasia, Spondyloepiphyseal Dysplasia Congenita, and Pseudoachondroplasia.