Back Muscles Flashcards
region, origin, insertion, action, innervation, blood supply, extra notes
Trapezius
Group: Superficial, Subgroup:Superficial.
Origin: Superior, Nuchal Line, Nuchal Ligament, Spinous Process C7-T12.
Insertion: Spine of Scapula, Acromion, Lateral 1/3 of Clavicle.
Action: Scapula- superior fibers:elevate, medial fibers: retract, inferior fibers: depress
Innervation: Spinal Acessory Nerve CNXI
Blood: Superficial Branch of Transverse Cervical Artery
Notes: broad origin, narrow insertion, workout: Shrugs
Latissimus Dorsi
Group: Superficial, Subgroup:Superficial
Origin: Spinous process T6-12, Thoracolumbar Fascia, Iliac Crest
Insertion:Intertubercular Sulcus of Humerus
Action:extends and adducts humerus, pulls trunk toward humerus
Innervation:Thoracodorsal Nerve C6-8 (collateral branch of brachial plexus)
Blood: Thoracodorsal artery (from subscapular branch of artery)
Notes:Workout: Lat pull down, Pull up
Rhomboid Major and Minor
Group: Superficial Supgroup: Deep
Origin: Minor: Nuchal Ligament, Spinous Process C7,T1.
Major: Spinous Process T2-T5
Insertion: medial border of scapula
Action: retract scapula
Innervation: Dorsal Scapular Nerve C4-5 (collateral Branch of brachial plexus)
Blood: Dorsal Scapular Artery
Notes: workout: prone lateral raises. use scapular spine to distinguish
Levator Scapulae
Group: Superficial Supgroup: Deep Origin: Transverse Processes C1-4 Insertion: Superior Angle of Scapula Action: Elevates Scapula Innervation: Dorsal Scapular Nerve C4-5 (collateral Branch of brachial plexus) Blood: Dorsal Scapular Artery Notes: workout: neck extensions
Serratus Posterior Superior
Group: intermediate
Origin: Nuchal Ligament, Spinous Process C7-T3
Insertion: superior border ribs 2-4
Action: elevates ribs for inspiration
Innervation: 2nd-5th intercostal nerves
Blood: –
Notes: unlike rhomboids, these attach to thoracic cage, insertions have serrated appearance
Serratus Posterior Inferior
Group: Intermediate Origin: Spinous Process T11-L2 Insertion: inferior border ribs 8-12 Action:depresses ribs for expiration Innervation: anterior rami of T9-T12 Blood: -- Notes:unlike rhomboids, these attach to thoracic cage, insertions have serrated appearance
Splenic Capitis/ Cervices (“splenius” )
Group: Deep Supgroup: Superficial
Origin: Nuchal Ligament, Spinous Process C7-T6
Insertion: Capitus: superior nuchal ligament and mastoid process
Cervices: Transverse processes C1-4
Action: alone-lateral rotation/flexion of neck, together: extension of neck
Innervation: dorsal rami of spinal nerves (segmentally innervated)
Blood: —
Notes: perpendicular to trapezius i.e. from ear to spine
Spinalis
Group: Deep Subgroup: Intermediate (Erector Spinae)
Origin: Cervical, Thoracic, Lumbar Spinous processes + cranium
Insertion:Cervical, Thoracic, Lumbar Spinous processes + cranium
Action:alone: laterally flex vertebral column, together: extend vertebral column
Innervation:dorsal rami of spinal nerves (segmentally innervated)
Blood—
Notes: named for what region they are i.e. spinalis cervicis
Longissimus
Group: Deep Subgroup: Intermediate (Erector Spinae)
Origin: Broad tendon spanning posterior Iliac crest, sacrum, lumbar spinous processes.
Insertion:Cervical, Thoracic transverse processes + mastoid process
Action:alone: laterally flex vertebral column, together: extend vertebral column
Innervation:dorsal rami of spinal nerves (segmentally innervated)
Blood—
Notes: run south to north, longest erector, hence the name
Illiocostalis
Group: Deep Subgroup: Intermediate (Erector Spinae)
Origin: Broad tendon spanning posterior Iliac crest, sacrum, lumbar spinous processes.
Insertion: lower borders of angles of ribs, cervical transverse processes
Action:alone: laterally flex vertebral column, together: extend vertebral column
Innervation:dorsal rami of spinal nerves (segmentally innervated)
Blood—
notes: “iliocostalis”- from iliac to costal region
Semispinalis (capitis, cervicis, thoracic)
Group: Deep Subgroup: Deep
Origin: Transverse Processes C4-T12
Insertion:capitis-occipital bone, cervicis-spinous processes in cervical region, cervicis-spinous processes in cervical region, thoracic- spinous processes thoracic region
Action:extend and stabilize vertebral column
Innervation:dorsal rami of spinal nerves (segmentally innervated)
blood:—
notes: semispinalis capitis forms roof of suboccipital triangle, is peirced by C2 nerve (greater occipital nerve)
Multifudus
Group: Deep Subgroup: Deep
Origin: Transverse Processes, posterior superior iliac spine, posterior sacrum
Insertion:spinous processes 2-4 segments superior to origin
Action:extend and stabilize vertebral column
Innervation:dorsal rami of spinal nerves (segmentally innervated)
blood:—
notes: form inverted “v” going from transverse to spinous - opposite of erector spinae. Best seen in lumbar region
Rotatores
Group: Deep Subgroup: Deep
Origin: Transverse Processes thoracic region
Insertion:spinous processes 1-2 segments superior to origin
Action:extend and stabilize vertebral column
Innervation:dorsal rami of spinal nerves (segmentally innervated)
blood:—
notes: brevis “short”-jumps 1 segment; longus “long” jumps 2 segments. best seen in thoracic
Rectus Capitis Posterior Major
Group: Back (Neck) Subgroup: Intermediate/deep (under Semispinalis C.s
Origin: Spinous Process of C2
Insertion: lateral portion of inferior nuchal line on occipital bone
Action: rotate C1 on C2 (shake head “no”)
Innervation:Dorsal Rami of C1 and C2
Blood:–
Notes:medial border of Suboccipital triangle
Rectus Capitis Posterior Minor
Group: Back (Neck) Subgroup: Intermediate/deep (under Semispinalis C.s
Origin: Posterior Arch of C1
Insertion: medial portion of inferior nuchal line on occipital bone
Action: rotate C1 on C2 (shake head “no”)
Innervation:Dorsal Rami of C1 and C2
Blood:–
Notes:”it’s minor” not involved in suboccipital triangle
