Pitkittäislihakset

Pitkittäislihakset refer to muscles that run lengthwise along a structure, such as a bone or an organ. In the human body, this term is often used in the context of the back muscles, particularly the erector spinae group. These muscles play a crucial role in maintaining an upright posture and facilitating movements like bending and extending the spine. They are long, strap-like muscles that extend from the pelvis to the skull.

When referring to other anatomical contexts, pitkittäislihakset can describe the muscles of the limbs that run parallel to the long axis of the bones. For instance, the muscles in the thigh and calf are largely considered pitkittäislihakset in their orientation. Their primary function in the limbs is to produce movement at the joints, such as flexion, extension, abduction, and adduction. The contraction of these muscles shortens them, pulling on the bones to which they are attached via tendons, thus generating force and motion.

In smooth muscle tissues, such as those found in the walls of the digestive tract or blood vessels, pitkittäislihakset are arranged in layers. These longitudinal muscles work in conjunction with circular muscles to propel substances through tubular structures via peristalsis or to regulate the diameter of vessels. The coordinated action of these muscle layers is essential for various physiological processes.