kylkivälilihaksille

Kylkivälilihakset, known in English as the intercostal muscles, are a group of muscles located between the ribs. These muscles play a crucial role in the mechanics of breathing. They are divided into two main groups: the external intercostals and the internal intercostals.

The external intercostal muscles are located on the outer surface of the rib cage, between the ribs. When they contract, they pull the ribs upwards and outwards, expanding the thoracic cavity. This action increases the volume of the chest, leading to inhalation.

The internal intercostal muscles lie beneath the external intercostals. Their contraction pulls the ribs downwards and inwards, decreasing the volume of the thoracic cavity. This action forces air out of the lungs, contributing to exhalation. While exhalation is largely passive during quiet breathing, the internal intercostals become more active during forced exhalation, such as when coughing or exercising.

The serratus posterior superior and inferior muscles, while sometimes considered accessory muscles of respiration, are distinct from the primary intercostal groups and have different functions related to rib movement. The proper functioning of the kylkivälilihakset is essential for efficient respiration, and their involvement can be observed in various respiratory conditions and physical activities.