Dactylothoracic Dysplasia (also known as Greenberg Skeletal Dysplasia) is a rare genetic disorder that affects the development of both the chest (thorax) and the fingers (digits). It is considered a type of skeletal dysplasia, which refers to a group of conditions that affect bone growth and development.

This condition is extremely rare and often severe, with most cases being diagnosed during pregnancy or shortly after birth.

What Happens in Dactylothoracic Dysplasia?

The condition primarily affects:

• Thorax (chest area) – which may be small and underdeveloped
• Fingers and toes – which may be shortened, fused, or abnormally formed

In many cases, the development of internal organs, especially the lungs, can be impacted due to the restricted space in the chest. This can lead to serious breathing difficulties after birth.

Other Names for the Condition

• Greenberg Skeletal Dysplasia
• Atelosteogenesis type III (in some contexts)
• Dactylothoracic dysostosis (used interchangeably)

Causes

Dactylothoracic Dysplasia is genetic, meaning it’s caused by a change (mutation) in specific genes responsible for bone and cartilage development. It is usually inherited in an autosomal recessive pattern, meaning:

• A child must inherit one faulty gene from each parent to be affected
• Parents are typically carriers and do not show symptoms themselves

One gene associated with this disorder is LBR (lamin B receptor), which plays a role in nuclear structure and cholesterol biosynthesis during development.

Symptoms

The condition is typically identified by the following physical traits:

• Very small, narrow chest
• Shortened ribs
• Abnormally formed or fused fingers and toes
• Short stature
• Underdeveloped lungs
• Flattened facial features

In some severe cases, it can also involve abnormalities in other organs or the skeleton, such as:

• Enlarged abdomen
• Poor bone mineralization
• Abnormal skull shape

Diagnosis

Diagnosis can be made before or after birth through:

• Prenatal ultrasound – can detect skeletal abnormalities in the womb
• X-rays – after birth to evaluate bone structure
• Genetic testing – confirms the diagnosis by identifying mutations in relevant genes
• Family history review – helpful in inherited cases

Due to the severity of the condition, it is often identified during routine prenatal scans.

Treatment

Unfortunately, there is no cure for Dactylothoracic Dysplasia. Because the chest and lungs are underdeveloped, most affected infants do not survive long after birth. Treatment in surviving or milder cases (if any) would focus on:

• Supportive care – such as respiratory support
• Multidisciplinary management – involving geneticists, pediatricians, and orthopedic specialists
• Genetic counseling – important for families who carry the gene to understand the risks in future pregnancies

Prognosis

The prognosis is generally poor, especially in severe cases where lung development is severely restricted. Most affected infants pass away shortly after birth due to respiratory failure.

In extremely rare or less severe forms, survival may be possible with intensive medical support, but long-term outcomes are uncertain.