Schmid metaphyseal chondrodysplasia

Schmid metaphyseal chondrodysplasia (SMCD) is a rare genetic disorder characterized by short stature, bowed legs, and other skeletal abnormalities. It is a type of metaphyseal chondrodysplasia, a group of disorders that affect the growth and development of the bones.

Overview

SMCD is caused by mutations in the COL10A1 gene, which provides instructions for making a protein that is essential for the normal development of cartilage and for its conversion to bone. The COL10A1 gene mutations that cause SMCD result in the production of an abnormal version of this protein, which disrupts the normal development of cartilage and prevents its conversion to bone, particularly in the long bones of the arms and legs.

Symptoms

The most common symptoms of SMCD include short stature, bowed legs, and waddling gait. Other symptoms may include pain or discomfort in the legs, especially during periods of rapid growth; limited range of motion in the hips and knees; and abnormal curvature of the spine (scoliosis or kyphosis). Some affected individuals may also have mild facial abnormalities, such as a prominent forehead or a flat nasal bridge.

Diagnosis

SMCD is typically diagnosed based on the characteristic signs and symptoms, particularly the skeletal abnormalities. The diagnosis can be confirmed by genetic testing to identify a mutation in the COL10A1 gene.

Treatment

There is currently no cure for SMCD. Treatment is focused on managing the symptoms and improving the quality of life for affected individuals. This may include physical therapy to improve mobility and reduce pain, and surgery to correct skeletal abnormalities. Some individuals may also benefit from growth hormone therapy to increase height.

Epidemiology

SMCD is a rare disorder. The exact prevalence is unknown, but it is estimated to affect fewer than 1 in 1 million people worldwide.

See also

• Metaphyseal chondrodysplasia
• Genetic disorder
• COL10A1

NIH genetic and rare disease info

• NIH info on Schmid metaphyseal chondrodysplasia

Schmid metaphyseal chondrodysplasia is a rare disease.