Most people have 24 ribs, arranged in 12 pairs. This is the typical number for both males and females.
Variations in Rib Count
While 24 ribs are the norm, variations exist. A small percentage of the population (approximately 1 in 500) may have an extra rib, often called a cervical rib. This extra rib can be present on the right side, the left side, or both. These ribs attach to the thoracic vertebrae.
Conversely, some individuals may have fewer than 24 ribs due to congenital conditions. These conditions range from minor variations to more serious deformities affecting lung function.
Ribs on Chest X-rays
A standard chest X-ray typically shows 8-10 ribs, depending on the depth of the breath taken during the examination. This doesn't indicate a deficiency in the total rib number.
Summary
The typical human rib count is 24 (12 pairs), although variations are possible. The presence of a cervical rib, or fewer than 12 pairs, can occur but is not typical.
