Ch 7 Musculature of the Back Flashcards
Bones involved in back muscle attachment
Occipital bone of the skull Vertebrae (cervical, thoracic, lumbar) Sacrum Hip Bone (iliac crest) Clavical Scapula Humerous
Single posterior projection from the junction of the two laminae
Spinous process
Lateral projection from the junction of a pedicle and a lamina (paired)
Transverse process
Acromion
Ledge that overlies the shoulder joint
Scapular spine
Prominent ridge continuous laterally with the acromion. It’s posterior surface is the crest, the edges of which are upper and lower lip.
Medial border of the scapular spine is _____
parallel with the vertebral column
Between the greater tubercle and the lesser tubercle in the humerous
Intertubecular groove
Origin of Trapezius
Occipital bone
Spinous process of ALL cervical vertebrae via ligaments nuchae
Spinous processes of ALL thoracic vertebrae
Insertion of Trapezius
Lateral third of the clavicle
Crest of the scapula
Acromion
(SAC)
Action of the Trapezius
Upward rotation of the scapula in which the inferior angle moves laterally
Elevation of scapula
Depression of scapua
Innervation of Trapezius
CN XI, accessory nerve
Ventral rami of CV3 and CV4
Origin of Latissimus Dorsi
Lower 3 or 4 ribs
Spinous processes of lower 6 thoracic vertebrae
Spinous processes of lumbar and sacral vertebrae via aponeurosis
Iliac crest
Insertion of Latissimus Dorsi
Intertubercular groove or sulcus of humorous
Action of Latissimus Dorsi
Adduction of arm at shoulder joint
Extension of arm at shoulder joint
Medial Rotation of arm at shoulder joint
Innervation of latissimus dorsi
Thoracodorsal nerve
Origin of Levator Scapulae
Transverse processes of CV1-CV4
Insertion of Levator Scapulae
The medial border of the scapula superior to the scapular spine
Action of Levator Scapulae
Elevation of the scapula
Innervation of levator scapula
Ventral rami C3 and C4
Origin of Rhomboid Minor
Spinous process of CV7 and TV1
Insertion of Rhomboid Minor
The medial border of the scapula at the scapular spine
Innervation of Rhomboid Minor
Dorsal Scapular Nerve
Action of Rhomboid Minor
Adduction of scapula
Origin of Rhomboid Major
Spinous processes of T2 - T5
Class from 2-5!
Insertion of Rhomboid Major
The medial border of the scapula inferior to the scapular spine
Action of Rhomboid Major
Adduction of scapula
Innervation of Rhomboid Major
Dorsal Scapular Nerve
Erector spinae
Consists of 3 longitudinally coursing muscles and constitutes the largest muscular mass of the back.
Above the 12th Rib
Erector spinal consists of the following columns of muscle from medial to lateral:
Spinalis
Longissimus
Iliocostalis
Centimeter wide muscle along the spinous process
Spinalis
The intermediate muscle of Erector Spinal, extending all the way to the skull; it is the longest column
Longissimus
The most lateral muscle of the erector spinal, extending from the ilium to the ribs.
Iliocostalis
The most important postural muscle that holds the spine erect by extending the vertebral column
Erector spinae
Innervation of erector spinae
Segmental from dorsal rami
Deep back muscle located in the neck
Splenius
2 parts of the spenius
Splenius Capitis
Splenius Cervicis
– Continuous at their origin, separable only at their insertion.
Splenius capitis
Extends from Ligamentum Nuchae and C7-T4 to the skull
Splenius Cervicis
Inferior portion of Splenius, courses from TV3-TV6 upward to CV1-CV3
When one side of the splenius acts, the head and cervical column ________
Rotate toward the same side
When both sides of the splenius act together the head and cervical column _____
Extend
Transversospinal group
Semispinalis
Multifidus
Rotatores
(See me roar)
Generally all muscles of transversospinal group originate from the ___ and insert into the ___ of certain vertebrae above it
Transverse process; spinous process
Deep back muscle that occupies upper half of the vertebral column
Semispinalis
How many vertebral segments does semispinalis course?
4-6
3 regional parts of Semispinalis
Semispinalis Capitis (biventer services)
Semispinalis Cervicis
Semispinalis Thoracis
Another name for semispinalis capitis is ____ because of ___
Biventer services, prominent intervening tendon
Semispinalis crevices is ___ to semispinalis capitis. Semispinalis thoracic is ____ to skkmispinaliscapitis in the thoracic region.
Deep, Inferior
Action of semispinalis capitis
Extends the head and rotates toward same side
Actions of semispinalis crevices and thoracis
Rotate vertebrae toward the opposite side
Deep back muscles that are best developed in the lumbar region deep to the erector spinae
Multifidi
How many vertebral segments does multifidus segment?
2-4
Where is multifidus best developed?
Lumbar region deep to erector spinae
Action of Multifidus
Rotates vertebral column toward opposite side
Innervation of Multifidus
Segmental from dorsal rami
Deep back muscles that are best developed in the thoracic region deep to semispinalis thoracic.
Rotatores
Deepest back muscles that lie directly on the laminae in the groove between the spines and transverse processes.
Rotatores
Rotatores longus
Rotatores muscle that crosses two vertebrae
Rotatores Brevis
Rotatores muscle that crosses one (the next) vertebrae
Action of rotators muscles
Rotate vertebral column toward opposite side
Innervation of rotators muscles
segmental from dorsal rami
Suboccipital muscles
4 muscles lying in the deep neck - Rectus Capitis Posterior Major - Rectus Capitis posterior minor Obliquus captifs iferior Obliquus captifs superior
Suboccipital triangle
Rectus capitis posterior major
Obliquus capitis inferior
obliques capitis superior
Which sub occipital muscle is not involved in the sub occipital triangle?
Rectus wapitis posterior minor
