35 terms

Extrinsic, Intermediate, and Intrinsic Deep Back muscles


Terms in this set (...)

Prox Attch: C7-T12, Superior Nuchal Line, Nuchal Ligament
Dist Attch: Scapular Spine, lateral 1/3 of clavicle, acromion

Innervation: Accessory Nerve
Blood Supply: Superficial branches of Transverse cervical artery

Function: Elevate, Retract, and Depress Scapula. Abduct upper limbs past 90 degrees (also with the help of Serratus Anterior)
Latissimus dorsi
Prox: Throacolumbar Fascia, T7-T12, Iliac Crest
Dist: Intertubercular Sulcus (bicipitial groove) of humerus

Innervation: Throacodorsal nerve
Blood Supply: Thoracodorsal Artery

function: Adduct Upper limbs, Extend Upper Limbs, Medially Rotate Upper Limbs
Rhomboid Major
Prox: Spinous Processes of T2 -T5
Dist: Medial Border of Scapula, between spine and inferior angle of scapula

Innervation: Dorsal Scapular Nerve

Blood Supply: Dorsal Scapular Artery and Deep branch of Transverse Cervical Artery.

Function: Retracts (Adduction) and Elevation of Scapula.
Rhomboid Minor
Prox: C7-T1
Distal: Medial border of scapula at the spine of scapula

Innervation: Dorsal Scapular Nerve
BS: Dorsal Scapular artery and deep branch of transverse cervical artery

Function: Retracts (Adducts) and raises scapula
Serratus Posterior Superior (SPS)
Prox: Nuchal Ligament, Spinous processes C7-T3

Distal: Ribs 2-5; lateral to angles

Innervation: Ventral Primary Rami of T9-T12; a.k.a Intercostal and Subcostal Nerves

BS: Dorsal Branches of Subcostal Arteries

Function: Elevate Ribs 2 -5 for respiration

This is an intermediate Muscle of the back; along with Serratus Posterior Inferior (SPI)
Serratus Posterior Inferior
Prox: T11-L2/L3
Dist: Ribs 9-12, lateral to angles

Innervation: Ventral Primary rami of T9-T12; aka intercostal or subcostal nerves

BS: Dorsal Branches of Subcostal Arteries

Function: Depress Ribs 9-12 for respiration
List all Extrinsic (Superficial) Muscles of the back
Trapezius, Latissimus Dorsi, Rhomboid Major and Minor, and Levator Scapulae
List Intermediate Muscles of the back
Levator Scapulae
Prox: C1-C4 (C1 is Atlas)
Distal: Superior angle of Scapula

Innervation: Dorsal Scapular Nerve
BS: Deep branch of Transverse Cervical Artery

Function: elevates Scapula
Triangle of Ausculation
A triangular structure made by the borders of trapezius, lat. dorsi, and medial border of scapula.

Lung expansion can be listened to through this structure. There are two in the top thoracic region.

similar structures to Lumbar triangles.
Lumbar triangles
Triangular structures with relatively low musculature created by Lat Dorsi, External Obliques, and Iliac Crest.

Inferior position to triangle of ausculation
Extrinsic Muscles
Act on Shoulder and Upper Limbs.
Petite's Hernia
Herniation through the Lumbar triangle. Typically occurs on the left lumbar triangle and usually occurs more in Males than Females.

If Herniation affects the bowel; there will be a bowel obstruction. If it affects kidney or urinary structures; there will be a urinary obstruction.
Deep Intrinsic Muscles
Spinae Erector Muscles, Spinotransversales, Transversospinales, Intersegmental Muscles

Muscles of Suboccipital Region
Functions of Intrinsic Deep Back Muscles
Act on Vertebral Column and Skull, Innervated by DORSAL rami of spinal nerves, and COVERED by thoracolumbar fascia
Splenius Capitis
Prox: Nuchal ligament and C7-T4
Distal: Mastoid Process and Superior Nuchal Line

Innervation: Dorsal Rami of Middle Cervical Nerves

BS: Most likely Branches of Transverse Cervical Artery

function: Works with Splenius Servicus to bitlaterally extend neck and Unilaterally rotate head
Splenius servicus
Prox: Spinous Processes of T3-T6
Dist: Transverse Processes of C1-C3

Innervation: Posterior Rami of Lower Cervical Nerves

BS: Same as Splenius .capitis

Function: same as splenius capitis
Most lateral of spinae erector muscle

Prox: Spinous Processes of Lumbar vertebrae, Iliac Crest, and Sacrum

Dist: Ribs lateral angles. Transverse Processes of C7-C4.

Second most lateral erector muscle.

Prox: Blends with Iliocostalis muscle at the lumbar/illiac crest region. Has same prox attachement.

Dist: Posterior Margin of Mastoid Process (similar attachment of Splenius Capitis)
Smallest of the spinae erector muscles. Most prominent in Throacic region. T10 upwards to cervical. Blends in with Semispinalis Capitis in the cervical region.

Prox: T10 or T11-L2
Dist: Spinous processes of C2 and eventually blends in with semispinalis capitis.
Function of Spinae Erector Muscles
Unilaterally: Lateral Flexion of Spine
Bilaterally: Spine Extension
Transversospinales Muscles
Semispinalis capits, servicus, Multifidus, Rotatores

Function: Unilateral: Small Fine Rotations and Lateral Flexion

Bilateral: Spine support/Spinal extension
Semispinalis Capitis
Prox: Transverse Processes of T1 -T5/T6, and Articular Processes of C4-C7

Dist: Medial Area between superior and inferior nuchal lines

Function: Bilateral: Extension of the Skull. Unilateral: Rotation of Skull towards contracted side.
Semispinalis Servicus
Prox: Transverse Processes of T1-T5/T6

Dist: Spinous Processes of C2 (axis) to C5

Function: Same as Semispinalis. capitis. Works with it to achieve function.
spans 2-4 vertebrae and most prominent in lumbar region.
Prox: Many origins including Lumbar regions, thoraic, and cervical transverse processes. Also Includes Iliac crest and sacrum.

Distal: Base of Spinous Processes of all vertebra from L5 to C2.

Function: Extend Spine
Small muscles that attach from transverse or articular processes and insert on spinous processes.

Prox: Transverse processes of Lumbar and Thoracic. Also on Articular processes of Cervical processes.

Distal: Spinous Processes of Lumbar, Thoracic, and Cervical regions.

Usually spans 1 to 2 vertebra.
Segmental Muscles
Levatores Costarum and Interspinales.
Levatores Costarum
Arises from transverse Processes of C7 and T1 to T11.

They have an oblique lateral and downward direction.

Insert on the rib directly below the vertebra of origin.

Contraction elevates the ribs.
Pass through adjacent spinous processes AND Intertransversarii, which pass between adjacent transverse processes.

These muscles stabilize the spinal column allowing for more effective movement by large muscles.
Suboccipital Muscles
Muscles at the base of the skull that allow for head movement.

Connection of Atlas and Axis and connect both vertebra to base of skull.

Rectus Capitis Posterior Major
Rectus Capitis Posterior Minor
Obliquus Capitis Superior
Obliquus Capitis Inferior
Rectus Capitis Posterior Major
Prox: Spinous Processes of Axis (C2)
Dist: Lateral Portion of Occipital Bone. Below Inferior Nuchal Line.

Innervation: Posterior Ramus of C1

BS: Branches of Vertebral and Occipital arteries

Function: Extension of Head, rotation of face to same side as muscle
Rectus Capitis Posterior Minor
Prox: Posterior tubercle of atlas

Dist: Medial portion of occipital bone, below inferior nuchal line.

Innervation: Posterior Ramus of C1

BS: Branches of Vertebral and Occipital arteries

function: Extension of head
Obliquus Capitis Superior
Prox: Transverse Process of Atlas

Dist: Occipital Bone between superior and inferior nuchal line

Innervation: Post. ramus of C1

BS: Same as other SO muscles

Function: Extension of Head and bends it to same side.
Obliquus Capitis Inferior
Prox: Spinous Process of Axis

Dist: Transverse Process of Atlas

Innervation: same as other SO

BS: Same as other SO

Function: Rotation of face to same side.
Suboccipital Triangle
Triangle made form SO muscles.
Medial is RCPM, Lateral is OCS, Inferior is OCI.

Contents of this triangle include posterior ramus of C1 (the main nerve innervation for SO muscles) , vertebral artery, and associated veins.