Please enable JavaScript.
Coggle requires JavaScript to display documents.
Muscles of Back - Coggle Diagram
Muscles of Back
Deep intrinsic muscles
Superficial deep intrinsic
Splenius capitis
Innervated by dorsal rami of spinal nerves C4-C8
Medial attachment (origin): lower aspect of ligamentum nuchae, spinous processes of C7-T3/4
Lateral attachment (insertion): mastoid process, posterolateral aspect of occipital bone
Action: extends head (bilateral), rotate and lateral flexion of head (ipsilateral)
Splenius cervicis
Innervated by dorsal rime of spinal nerves C4-C8
Medial attachment (origin): spinous process of T3-T6
Lateral attachment (insertion): transverse processes of C1-C3/4
Action: extends cervical spine (bilateral), rotate and lateral flexion of cervical spine (ipsilateral)
Intermediate deep intrinsic (erector spinae)
Iliocostalis (3)
Iliocostalis Cervicis
Origin: angles of ribs 3-6
Insertion: transverse processes of C4-C6
Iliocostalis thoracis
Origin: posterior aspects of ribs 6-12; middle layer of TLF
Insertion: posterior aspect of ribs 1-6; transverse process of C7
Iliocostalis lumborum
Origin: from common tendon
Insertion: angles of ribs 6-12
COMMON INNERVATION: dorsal rami of spinal nerves that cross the muscle
COMMON ACTION: work as one unit on each side to lateral flex the spine, work as one unit one each side to rotate their segment (same side), bilaterally work to extend head and spine
Longissimus (4)
Longissimus capitis
Origin: transverse process of T1-T5; articular process of C7-C4
Insertion: mastoid process of temporal bone
Longissimus cervicis
Origin: transverse process of T1-T4/5
Insertion: transverse processes of C2-C6
Longissimus thoracis
Origin: posterior medial iliac crest; posterior sacrum; spinous processes L3-S3
Insertion: transverse process of T1-T12; ribs 2-12
Longissimus lumborum
Origin: posterior iliac bone and posterior-superior iliac spine
Insertion: dorsal aspect of transverse processes of L1 to L5
COMMON INNERVATION: dorsal rami of spinal nerve by segment as spinal nerves crossed by muscles
COMMON ACTION: work on as one unit on each side to laterally flex and rotate spine (same side); bilaterally work to extend spine (by segment)
Spinalis (3)
Spinalis cervicis (may be absent)
Origin: spinous process of C7; ligamentum nuchae
Insertion: spinous process of C2 (axis)
Spinalis thoracis
Origin: spinous process of T11-L2
Insertion: spinous process of T1-T8
Spinalis capitis
Origin: transverse process of C7-T7; articular processes of C4-C6
Insertion: occipital bone between super and inferior nuchal lines
COMMON INSERTION: Innervated by dorsal rami of spinal nerve crossed by muscle
COMMON ACTION: work as one unit on each side to laterally flex spine; bilaterally works to extend (by segment)
Deep intrinsic - transversospinalis
Semispinalis (3)
COMMON ORIGIN: from transverse processes of C4-T10 (fibers ascent 4-6 vertebral segments)
COMMON INSERTION: spinous process of C2-T4; the occipital bone
COMMON ACTIONS: extends and CONTRA-LATERALLY rotates the head and spine
Innervation: dorsal rami of spinal nerves
Multifidus
Origin (broad): common tendinous origin of erector spinae, sacrum, posterior iliac spine, mamillary process, transverse process of T1-T3, articular processes of C4-C7
Insertion: spinous process of vertebrae
Action: stabilize the vertebral column
Innervation: dorsal rami of spinal nerves
Rotatores (2)
Longus -- fibers ascend 2 segments above
Brevis -- fibers ascend 1 segment above
Origin: vertebral transverse processes
Insertion: lamina and spinous process
Actions: stabilizes the vertebral column, PROPRIOCEPTION
Innervation: dorsal rami of spinal nerves
Deep intrinsic - segmental
Interspinalis
Innervated by dorsal rami of spinal nerve
Origin/Insertion: spans between adjacent spinous processes of C2-C7; T2-T12; L2-L5
Action: extend vertebrae, stabilize for posture
Intertransversarii
Innervated by ventral rami of nerve crossed by muscle
Spans between transverse processes of cervical and lumbar spine
Action: postural control, proprioception, lateral flexion same side of lumbar spine
Levatores costarum
Origin: tips of transverse processes of C7/T1-T11
Insertion: pass inferolateral and attach to rib between tubercle and angle
Innervation: dorsal rami of C8-T11 spinal nerves
Actions: elevates ribs, PROPRIOCEPTION, assist in respiration, assists in lateral flexion of spine
Suboccipital region
Rectus Capitis Posterior Major
Innervation: dorsal rami of C1
Origin: spinous process of C2
Insertion: inferior nuchal line
Action: extend head (both), rotate head (same)
Rectus Capitis Posterior Minor
Origin: posterior tubercle of C1
Insertion: inferior nuchal line
Innervation: dorsal rami of C1
Action: extend head bilaterally
Obliquus capitis superior
Origin: transverse process of C1
Insertion: between superior and inferior nuchal line
Innervation: dorsal rami of C1
Action: lateral flexion of head (same), extends head (both)
Obliquus capitis inferior
Origin: spinous process of C2
Insertion: transverse process of C1
Innervation: dorsal rami of C1
Action: rotates head (same)
Superficial extrinsic muscles
Superficial extrinsic
Trapezius
Innervated by CN XI
Medial attachments: superior nuchal line, external protuberance of occipital bone, ligamentum nuchae, spinous process and superspinous ligaments of C7-T12
Lateral attachments: posterior border of lateral 1/3 of clavicle, anterior border of acromion, anterior border of scapular spine
Action: elevates and retracts scapula, lateral flexion of head (ipsi), rotation of head (contra), retracts (adducts) humerus, depresses scapula, stabilizes scapula for GH movement
Latissimus dorsi
Innervated by the thoracodorsal nerve (from C6-C8)
Lateral attachments: floor of bicipital or inter-tubercular groove
Medial attachments: spinous processes of T6-T12; posterior layer of TLF which attaches to spinous process of L1-L5 and base of sacrum, iliac crest, and ribs 8-12; inferior angle of scapula
Action: adduction of humerus, internal/medial rotation of humerus, assists in humeral extension and flexion, may depress scapula
Levator scapulae
Innervated by dorsal scapular nerve (from C4-C5)
Medial attachments (origin): transverse process of C1 to C4
Lateral attachments (insertions): medial border of scapula from superior angle to root of spine of scapula
Action: elevate scapula, assists in rotating glenoid fossa downward, extends neck (bilateral), lateral flexion and rotation of neck (ipsilateral)
Rhomboid (2)
Rhomboid major
Innervated by dorsal scapular nerve (from C4-C5)
Medial attachment (origin): spinous processes and supraspinous ligament of T2-T5
Lateral attachment (insertion): lower medial border of scapula from root of spine to inferior angle
Actions: retracts scapula, assists in elevation of scapula, assists in rotating glenoid fossa downward, stabilizes scapula for GH movement
Rhomboid minor
Innervated by dorsal scapular nerve (from C4-C5)
Medial attachment (origin): lower ligamentum nuchae, spinous processes and supraspinous ligament of C7-T1
Lateral attachment (insertion): medial border of root of spine of scapula
Actions: retract scapula, assists in elevation of scapula, assists in rotating glenoid fossa downward, stabilizes scapula for GH movement
Intermediate extrinsic
Serratus posterior superior
Innervated by intercostal nerve
Medial attachment (origin): lower part of ligamental nuchae, spinous process of C7-T3
Lateral attachment (insertion): ribs 2-4/5
Actions: PROPRIOCEPTION
Serratus posterior inferior
Innervated by intercostal nerve
Medial attachment (origin): spinous process of T11-L2/3
Lateral attachment (insertion): ribs 9-12
Actions: PROPRIOCEPTION
Extrinsic muscle (not deep)
Quadratus lumborum
Innervated by ventral rami of L1-L4
Plays a role in referred pain
Insertion: attaches from rib 12 to internal lip of posterior aspect of iliac crest
Origin: iliac crest lateral to erector spinae, iliolumbar ligament at L5
Actions: extension of trunk (both), lateral flexion (opp) of lumbar spine, elongate thorax during inspiration (anchors rib 12 in place)