Bronchial cartilages

Bronchial cartilages are C-shaped or irregular plates of hyaline cartilage that provide structural support to the walls of the bronchi, preventing airway collapse during respiration.

• In the main (primary) bronchi, the cartilage rings are C-shaped (similar to tracheal rings), with the open end facing posteriorly where smooth muscle and connective tissue complete the wall.

• In the lobar and segmental bronchi, the cartilage becomes arranged as irregular plates or crescents rather than complete rings, distributed around the airway circumference.

• As the airways branch further into smaller bronchi, the cartilage plates become progressively smaller and more sparse.

• At the level of the bronchioles (airways ~1 mm in diameter), cartilage is absent entirely, and airway patency is maintained by the elastic recoil of surrounding lung parenchyma and smooth muscle tone.