Thorax 01: Muscles and Osteology of the Back Flashcards
Sagittal Plane
Cuts the body into two lateral sides (right and left)
Coronal Plane
Cuts the body into a dorsal and ventral side
Transverse Plan
Cuts the body near the waist into top and bottom
Anatomical Position
Person is flat with feet apart, arms down and palms facing forward
Another term for ventral
Anterior
Another term for dorsal
Posterior
Another word for cranial
Superior
Another word for caudal
Inferior
Medial
Closer to midline
Lateral
Farther from midline
Superficial
Closer to surface
Deep
Away from surface
What does the thorax body seciton plan look like?
No uritogenital structures, aorta displaced to the left, esophagus closer to the vertebrae, heart folded in center, celom lines pulmonary cavities which contains lungs, no portal vein, wall formed by ribs with 3 layers of
muscle between them
Endothoracic fascia
a layer of loose connective tissue that lines the inside of the thoracic wall
Trapezius
A hypaxial limb muscle of the upper back, usually by the shoulder
Muscle reflection
Performing an incision in a muscle and folding it back to see beneath it
Levator scapulae
A hypaxial limb muscle beneath the trapezius; usually around the neck
Rhomboid muscle minor
A hypaxial limb muscle beneath the trapezius, usually by the clavicle and above the rhomboid muscle major
Rhomboid muscle major
A hypaxial limb muscle beneath the trapezius; usually just under the rhomboid muscle minor
Thoracolumbar fascia
A layer of connective tissue that separates epaxial muscle from hypaxial muscle
Serratus Posterior
The deepest hypaxial muscle; connects to the ribs
Secondary curvature
The normal curving of the spine.
Primary curvature
The normal curving of the spine that is present in the fetus (unlike secondary) and is concave anteriorally; thoracic curvature and sarcococcygeal curvature
Vertebral foramen
The hole in the middle of the vertebra
Neural arch
Vertebral part consisting of pedicle and lamina
Vertebral body
The bottom part of the vertebra
Spinous process
The vertebral bone sticking out upwards
Articular process
The vertebral bone sticking out diagonally
Transverse process
The vertebral bone sticking out laterally
How can we recognize cervial vertebra?
Shorter processes; they specifically have foramen transversarium; bifidous spinal processes
How can we recognize thoracic vertebra?
There is one facet in transverse process and two demi-facets in articular process for connecting ribs; heart shaped body
How can we recognize lumbar vertebra?
Much larger vertebral body; long transverse process; no facets
Foramen transversarium
Unique to cervical vertebra; an opening on each of the transverse processes which gives passage to the vertebral artery and vein and a sympathetic nerve plexus
Pars interarticularis
One of the two weak spots of the lumbar vertebra
Sacrum
Fusion of the 5 sacral vertebra; articulates with the pelvis
Longitudinal ligaments
Ligaments that run down the vertebral column. Divided into anterior and posterior
Anterior longitudinal ligaments
Strong and thick; resists hyperextension
Posterior longitudinal ligaments
weaker; resists hyperflexion and herniation
Ligamenta flava
Elastic ligaments joining laminae
Interspinous ligaments
Spans spinous processes
Supraspinous ligaments
Strong ligaments that span the tips of spinous processes
Ligamentum nuchae
Cranial continuation of supraspinous ligaments that holds the head up
Herneated disk
Seeping of nucleus pulposus from the vertebral body; damages spinal nerves
Ankylosin spondylitis
Fusion of spinal joints due to inflammation
Spondyloisthesis
Anterior slippage of lumbar vertebra, usually L5
How many spinal arteries are there?
One anterior and two posterior
Trapezius innervation
Cranial nerve 11 (accessory spinal nerve), C3-C4
Trapezius action
Adducts, rotates, elevates, depresses scapula
What are the superficial back muscles?
Trapezius, levator scapulae, rhomboid major, rhomboid minor, latissimus dorsi
Levator scapulae innervation
nerves to levator scapulae, dorsal scapular nerve
Levator scapulae action
Elevates scapula and rotates glenoid cavity
Rhomboid major innervation
dorsal scapular nerve
Rhomboid minor innversation
dorsal scapular nerve
Rhomboid major action
adducts scapula
Rhomboid minor action
adducts scapula
Latissimus dorsi
A superficial back muscle that spans the back
Latissimus dorsi innervation
Thoracodorsal nerve
Latissimus dorsi action
Adduct, extend, and rotate arm medially; depresses scapula
What are the muscles of the spinotransverse group?
Splenius capitis and splenius cervicis;
Spinotransverse group muscle innervation
Dorsal rami of cervical spinal nerves
Spinotransverse group muscle action
extends, rotates, laterally flexes head and neck
What are the muscles of the erector spinae group?
Spinalis, Longissimus, Ilocostalis
Erector spinae group inntervation
Dorsal rami of spinal nerves
Erector spinae group action
extend, rotate, laterally flex vertebral column and head
What are the muscles of the transversospinalis group?
semispinalis, multifidus, and rotatores
Transversosplinalis group innervation
Dorsal rami of spinal nerves
Transversosplinalis gruop action
Extend and rotate head, neck and trunk
Pectoralis major
A muscle in the pectoral region
Pectoralis major innervation
lateral and medial pectoral nerves
Pectoralis major action
Flexes, adducts, and medially rotates arm
Pectoralis minor
A muscle in the pectoral region underneath the pectoralis major
Pectoralis minor innervation
Medial pectoral nerve
Pectoralis minor action
Depresses scapula and elevates ribs
Subclavius
A muscle in the pectoral region attached to the clavicle
Subclavius innervation
Nerves to the subclavius
Subclavius action
Depresses lateral part of the clavicle
Serratus anterior
A muscle in the pectoral region
Serratus anterior innervation
Long thoracic nerve
Serratus anterior action
Upward rotation of scapula; abducts and elevates arm upwards
What are the muscles found in the thoracic wall
External intercostals, internal intercostals, innermost intercostals, transversus thoracis, subcostalis
Thoracic wall muscle innervation
Intercostal nerves
External intercostal muscle action
Elevates ribs during inspiration
Internal intercostal muscle action
Elevates interchondral part of rib, depresses costal part of rib
Innermost inercostal muscle action
Elevates ribs
Transversus thoracis muscle action
Depresses rib
Subcostalis muscle action
Elevates ribs
Diaphragm
A muscle found in the inferior thoracic region and separates it from the abdomen
Diaphragm innervation
C3, C4, C5 (phrenic nerve)
Diaphragm action
Aids in breathing
What are the planes of movement of the spine?
1) flexion and extension
2) lateral flexion
3) Rotation
Atlantooccipital joint
Involved in head nodding
Atlantoaxial joint
Involved in head shaking
Ligamentum nuchae attachments
Spinous process of C7 and the external occipital protuberance
Spondylosis
A break in the vertebra
What is a muscle origin? What is a muscle attachment point?
Immovable fixation point; movable fixation point
Origin of Trapezius
Vertebral column
Insertion of Trapezius
Spine of scapula
Conus medularus
The tapering, bottom end of the spinal cord
cauda equina
A bundle of spinal nerves inferior to the conus medularis
