A cervical rib is an extra rib that forms above the normal first rib, growing from the base of the neck just above the collarbone. The defect is present at birth, but usually not noticed until later in life.

Itmay be a fully-formed bony rib or just a thin strand of tissue fibres, which will not always show up on any X-ray or MRI scans you may have.

If the extra rib is only partially formed, it may either end in a swelling that shows as a lump in the neck or it may tail off into a fibrous band of tissue that connects to the first properrib.

A cervical rib can sometimes squash one of the nearby blood vessels or nerves, causing problems such as Twisted neck and numbness in the arm. These symptoms are collectively known as thoracic outlet syndrome.

Content supplied by the NHS Website

Medically Reviewed by a doctor on 21 Jun 2016