Absent Patella

What is Absent patella?

The data for Absent Patella, which is the name given to the absence (or a significant reduction of size) of the patellar bone (aka. the knee cap), is limited to only a few individulas in a limited number of families. Absent patella is also known as Isolated patella aplasia-hypoplasia. It is is an extremely rare genetic condition that develops congenitally.

What are the symptoms of Absent Patella?

Common symptoms of Absent Patella include the following:

• Abnormality of the skin
• Autosomal dominant inheritance
• Patellar aplasia
• Patellar hypoplasia

What causes Absent Patella?

Although, as in many rare diseases that have so few patients, the underlying cause is not always certain. However Absent Patella is know to be inherited by an autosomal dominant pattern. The mutated gene is a dominant gene and the patient only need to have one gene that is mutated to develop the disorder. The genetic abnormality leads to structural issues with collagen and connective tissues.

How is Absent Patella diagnosed?

Absent Patella can be diagnosed visually and confirmed by imaging.

What are the treatments for Absent Patella?

A very rare condition, Absent Patella, usually causes no issues for the patient. In a study by Guidera and associates, approximately 50% of children with nail patella syndrome (a similar disorder) underwent knee surgery to treat instability.

Where can I find out more about Absent Patella?

• NIH
• Check Orphan
• Indian Journal of Orthopaedics