Several sets of muscles support and propel the torso. The abdominal wall muscles help transfer force between the upper and lower body, and they also protect the delicate internal organs. Their most important function is to support the back. The muscles of the torso extend in several directions. They help maintain posture and aid the spinal muscles when bending, twisting, and other movements. Research Abdominal Wall
Bones (or osseous material) serve a number of diverse purposes in the human anatomy. In addition to providing structure, protection, and support for the organs of the body, bones also house marrow, which produces blood cells. Within the bones are also stored the calcium deposits which the body may access, via resorption, when needed. Additionally, bones detoxify the system, by removing heavy metals, such as lead and arsenic, as well as other toxins, from the bloodstream. Osseous tissue itself is made of water (about 1/4 of the bone weight), organic material (about 1/3 of the bone weight, most of which is the protein, ossein) and inorganic minerals (calcium, phosphorus, and magnesium predominate, though iron, sodium, potassium, chlorine, and fluorine are also present in small amounts). Most bones (with the exception of those of the skull) are initially pre-formed in cartilage and are then ossified as the newborn develops.
Two basic classification methods exist to categorize the bones of the body. These two classification systems are based upon anatomical location (axial or appendicular), and shape (long, short, flat, and irregular). Axial bones are the eighty bones which lie along the central, vertical axis of the body and support and protect the head and torso and include the skull and the spinal column.
Appendicular bones include the one hundred twenty-six bones which comprise the appendages, including the shoulders and hips, arms and legs, hands and feet, and fingers and toes. The shape classifications include long bones (such as the radius, humerus, and femur), the short bones (such as the carpals, tarsals, and manual and pedal phalanges), flat bones (such as the sternum, cranium bones, and scapulae), and irregular
bones (such as the vertebrae). Research Bone
The external oblique (obliquus externus abdominis) is a large, thin sheet of muscle that runs along the side of the torso and partly on the front. The muscle is divided into two portions; and upper thoracic portion and a lower flank portion. The thoracic portion is located along the rib cage. The lower flank portion is located along the side of the abdomen between the rib cage and the pelvis. The muscle originates from the fifth to twelfthribs and inserts in the lip of the iliac crest, inguinal ligament, and the rectus abdominis muscle. The individual ribs can be seen beneath this muscle when it is relaxed. Most of this muscle is concealed by a cushion of fat. The two portions meet at the waist. It is innervated by branches of the lower thoracic nerve and supplied branches of the lumbarartery and the intercostal arteries. This muscle assists the rectus abdominis muscle in flexing the spine when the trunk twists or turns. It also supports the abdominal organtissue. Research External Abdominal Oblique
The external oblique (obliquus externus abdominis) is a large, thin sheet of muscle that runs along the side of the torso and partly on the front. The muscle is divided into two portions; and upper thoracic portion and a lower flank portion. The thoracic portion is located along the rib cage. The lower flank portion is located along the side of the abdomen between the rib cage and the pelvis. The muscle originates from the fifth to twelfthribs and inserts in the lip of the iliac crest, inguinal ligament, and the rectus abdominis muscle. The individual ribs can be seen beneath this muscle when it is relaxed. Most of this muscle is concealed by a cushion of fat. The two portions meet at the waist. It is innervated by branches of the lower thoracic nerve and supplied branches of the lumbarartery and the intercostal arteries. This muscle assists the rectus abdominis muscle in flexing the spine when the trunk twists or turns. It also supports the abdominal organtissue. Research External Oblique
The gluteus medius (mesogluteus) is a wide, fan-shaped muscle that originates from the ilium of the pelvis between the anterior and posterior gluteal lines. It runs from the outer portion of the ilium (pelvis), up to the crest of the ilium and tapers into a strong flattened tendon at its insertion on the femur (upper leg bone) . It is innervated by the superior gluteal nerve and supplied by the superior gluteal artery. The gluteus medius is partly covered by the gluteus maximus. You can feel the crest of the gluteus medius through the skin. It moves the thigh outward and rotates it, as when walking or running. It keeps the torsoupright during walking when one foot is touching the ground and the other is not touching the ground. The gluteus minimus lies just beneath the gluteus medius and works with it. Research Gluteus Medius
The internal oblique (obliquus internus abdominis) is a small, thin, deep muscle of the abdomen. It runs diagonally opposite underneath the external oblique. It has a quadrilateral form originating from the hipbone (crest of the ilium), and extending to the cartilage of the lower ribs (the tenth, elenenth, and twelfthribs). It is innervated by the lower thoracic nerves and supplied the intercostal and lumbar arteries. This muscle protects a weak point in the abdominal wall and works with the external oblique to help twist the torso. Research Internal Oblique
Several sets of muscles support and propel the torso. The abdominal wall muscles help transfer force between the upper and lower body, and they also protect the delicate internal organs. Their most important function is to support the back. The muscles of the torso extend in several directions. They help maintain posture and aid the spinal muscles when bending, twisting, and other movements. Research Muscles of the Abdominal Wall
The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
Abbreviations
Research Torso
