Logan Steele
The trunk, or torso, is the central part of the body to which the head and limbs are attached. It houses all the vital organs of the human body, except the brain. The trunk muscles are divided into two large groups, depending on their location. The anterior trunk muscles cover the anterolateral part of the trunk and include the chest and abdominal muscles. The posterior trunk muscles are more commonly referred to as the muscles of the back. The trunk muscles play a crucial role in protecting the organs and enabling essential body activities such as breathing, movement, defecation, and micturition.
| Characteristics | Values |
|---|---|
| Location | The trunk is the central part of the body to which the head and limbs are attached |
| Organs | The trunk houses all vital organs except the brain, including the heart, lungs, stomach, liver, small and large intestines, pancreas, gall bladder, and esophagus |
| Muscle Groups | Anterior (front) and posterior (back) muscles |
| Anterior Muscle Functions | Respiration, torso movement, and maintenance of balance and <co: 4,7,9,17,18>posture |
| Posterior Muscle Functions | Movement of the shoulder, head, and neck, and assisting in respiration, posture, and balance |
| Anterior Trunk Muscles | Pectoralis major, pectoralis minor, serratus anterior, subclavius, intercostal (external, internal, and innermost), subcostal, transversus thoracis, rectus abdominis, pyramidalis, external abdominal oblique, internal abdominal oblique, and transversus abdominis |
| Posterior Trunk Muscles | Superficial (extrinsic) and deep (intrinsic) muscles |
| Superficial Posterior Muscles | Responsible for movement of the upper limb |
| Deep Posterior Muscles | Act on the trunk, facilitating movement of the head and neck, and maintaining posture and balance |
Explore related products
What You'll Learn
- The trunk houses vital organs and is divided into anterior and posterior muscles
- Anterior trunk muscles include the chest, abdominal, and pelvic regions
- Posterior trunk muscles include the back, suboccipital, and perineum regions
- The abdominal wall consists of four muscle pairs, with the obliques being the most superficial
- The trunk muscles assist in essential body activities such as breathing, movement, defecation, and micturition
The trunk houses vital organs and is divided into anterior and posterior muscles
The trunk, or torso, is the central part of the body to which the head and limbs are attached. It houses all the vital organs of the human body, including the heart, lungs, stomach, liver, small and large intestines, pancreas, gall bladder, and oesophagus. The trunk muscles are divided into two large groups, depending on their location: the anterior muscles and the posterior muscles.
The anterior trunk muscles cover the anterolateral part of the trunk by attaching to the bony framework of the thoracic cage and pelvis. These muscles are grouped into the muscles of the thoracic cage and the muscles of the abdominal wall. The muscles of the thoracic cage include the pectoralis major, pectoralis minor, serratus anterior, subclavius, intercostal (external, internal, and innermost), subcostal, and transversus thoracis muscles, including the diaphragm. These muscles attach the upper limb to the axial skeleton of the trunk and support the thoracic cage. They are also involved in movements of the upper limb and respiration. The pectoralis major is a large, fan-shaped, superficial muscle located on the anterior thoracic wall. The intercostal muscles form the chest wall and function in respiration. The diaphragm is a sheet-like muscle that extends underneath the rib cage and aids in respiration by physically moving the lungs. The obliques are abdominal muscles that assist during bending and twisting of the torso. There are five muscles that form the abdominal part of the anterior trunk: the rectus abdominis, pyramidalis, external abdominal oblique, internal abdominal oblique, and transversus abdominis. The first three are classified as vertical muscles and are located near the midline, while the latter two are flat muscles located more laterally.
The posterior trunk muscles, commonly referred to as the muscles of the back, are divided into two functional groups: superficial or extrinsic muscles of the back, and deep or intrinsic muscles of the back. The superficial muscles of the back are responsible for moving the shoulder, while the intermediate muscles assist in the movement of the rib cage during respiration. The intrinsic back muscles facilitate the movement of the head and neck and are fundamental in maintaining posture and balance. The erector spinae group of muscles on each side of the vertebral column is a large muscle mass that extends from the sacrum to the skull. These muscles are primarily responsible for extending the vertebral column to maintain erect posture.
Healing Muscle Spasms: Natural Ways to Find Relief
You may want to see also
Explore related products
Anterior trunk muscles include the chest, abdominal, and pelvic regions
The trunk, or torso, is the central part of the body to which the head and limbs are attached. The trunk muscles are divided into two large groups, depending on their location: the anterior trunk muscles and the posterior trunk muscles.
The anterior trunk muscles are those associated with the front of the body, including the chest, abdomen, and pelvis. These muscles cover the anterolateral part of the trunk by attaching to the bony framework of the thoracic cage and pelvis.
The chest muscles, also known as the pectoral muscles, function in respiration and facilitate movement of the upper arm. The pectoralis major is a fan-shaped muscle covering the chest and is comprised of clavicular and sternocostal regions. It forms the bulk of the chest area and can be easily seen on the surface in some people, such as weightlifters. The pectoralis minor is a smaller muscle that lies beneath the pectoralis major. It originates from the third to fifth ribs and attaches to the scapula.
The abdominal muscles function in torso movement and maintaining balance and posture. There are five muscles that form the abdominal part of the anterior trunk: the rectus abdominis, pyramidalis, external abdominal oblique, internal abdominal oblique, and transversus abdominis. The rectus abdominis is often referred to as the "six-pack abs" and is involved in trunk stabilization and bending. The obliques are abdominal muscles that assist during bending and twisting of the torso. The transversus abdominis is a thin, radiating muscle located on the internal aspect of the anterior thoracic wall.
The pelvic outlet is formed by two muscular sheets and their associated fascia. The anterior trunk muscles also include the diaphragm, a sheet-like muscle that extends underneath the rib cage and aids in respiration by physically moving the lungs.
Muscle Injury Prevention: Understanding the Power of Muscles
You may want to see also
Explore related products
Posterior trunk muscles include the back, suboccipital, and perineum regions
The trunk, or torso, is the central part of the body to which the head and limbs are attached. The trunk muscles are divided into two large groups depending on their location: the anterior trunk muscles and the posterior trunk muscles.
The posterior trunk muscles include the muscles of the back, suboccipital region, and perineum region. The back is characterised by numerous muscle groups that allow movement of the shoulder, head, and neck, as well as aid in respiration and maintain posture and balance.
The superficial muscles of the back are responsible for the movement of the shoulder. The intermediate muscles of the back assist in the movement of the rib cage during respiration. The intrinsic back muscles facilitate the movement of the head and neck and are fundamental in maintaining posture and balance. The latissimus dorsi is an example of a posterior torso muscle. It is an expansive muscle located in the lower region of the back, consisting of four parts. The trapezius is another example of a superficial posterior muscle. It is the most superficial muscle of the back and forms a broad, flat triangle.
The multifidus is a very thin muscle situated underneath the semispinalis. It is key in maintaining posture through the spine. The rotatores muscles are located underneath the multifidus and are most developed in the thoracic region.
Hydroxycut's Muscle-Burning Effects: What You Need to Know
You may want to see also
Explore related products
The abdominal wall consists of four muscle pairs, with the obliques being the most superficial
The trunk, or torso, is the central part of the body to which the head and limbs are attached. The trunk muscles are divided into two large groups depending on their location: the anterior trunk muscles and the posterior trunk muscles. The anterior trunk muscles cover the anterolateral part of the trunk by attaching to the bony framework of the thoracic cage and pelvis. These muscles are grouped into the muscles of the thoracic cage and the muscles of the abdominal wall.
The rectus abdominis is a pair of muscles that run down either side of the middle of the abdomen from the ribs to the pelvis. They are divided into two segments by a muscle called the linea alba. The rectus abdominis often forms bumps, sometimes called a "'six-pack'", when someone has a trim, fit abdomen. The pyramidalis is a small, triangular vertical muscle located at the base of the pubic bone. It sits in front of the rectus abdominis and attaches to the linea alba.
Posterior muscles include psoas major and quadratus lumborum bilaterally. The muscles of the back are divided into two groups: superficial (extrinsic) muscles and deep (intrinsic) muscles. The superficial muscles of the back are responsible for moving the upper limb, while the deep, or intrinsic, muscles act on the trunk.
Understanding Feline Musculature: A Guide to Cat Muscles
You may want to see also
Explore related products
The trunk muscles assist in essential body activities such as breathing, movement, defecation, and micturition
The trunk, or torso, is the central part of the body to which the head and limbs are attached. The trunk muscles have many important functions, including assisting with essential body activities such as breathing, movement, defecation, and micturition.
Breathing
The trunk muscles are essential for breathing. The diaphragm, a dome-shaped muscle that separates the thoracic and abdominal cavities, is the main muscle of breathing and is responsible for inspiration. The intercostal muscles, located in the spaces between the ribs, also play a role in breathing. They contract during forced expiration, and the external intercostal muscles contract to elevate the ribs during the inspiration phase of breathing.
Movement
The trunk muscles are involved in movements of the trunk, including flexion and rotation. They also assist in movements of the upper limb. The deep back muscles are responsible for maintaining posture and controlling head and spine movements. They extend along the vertebral column from the pelvis to the skull. The erector spinae group of muscles is primarily responsible for extending the vertebral column to maintain erect posture.
Defecation and Micturition
The abdominal muscles, which are part of the trunk musculature, contribute to changing the intra-abdominal pressure, which is essential for basic bodily functions such as defecation and micturition. The rectus abdominis muscle, in particular, acts as a flexor of the trunk and is involved in regulating intra-abdominal pressure.
Groin Muscles in Females: Fact or Fiction?
You may want to see also
Frequently asked questions
The trunk of the body is the central, main part of the body that houses all the vital organs and to which the limbs and head are attached. The trunk muscles are all of the muscles of the axial skeleton. They include the muscles of the chest, abdomen, pelvis, back, suboccipital region, and perineum region.
The anterior trunk muscles are those on the front of the body, including the muscles of the chest, abdomen, and pelvis. They are divided into the muscles of the thoracic cage and the abdominal wall. The muscles of the thoracic cage include the pectoralis major, pectoralis minor, serratus anterior, subclavius, intercostal, subcostal, and transversus thoracis muscles, including the diaphragm.
The trunk muscles are responsible for making and keeping the body erect, allowing it to sit and stand up, and maintaining posture and balance. They also assist essential body activities such as breathing, movement, defecation, and micturition.
