Back Myology Flashcards
The deep three layers of back muscle are called intrinsic muscles and are innervated by what nerve?
Posterior Rami
Trapezius Muscle
Origin: (4)
Insertion: (3)
Action: (5)
Nerve:
Origin
C7-T12, ligamentum nuchae, superior nuchal line, occipital protuberance
Insertion
Lateral 1/3 of clavical, acrominon, scapular spine
Action
Rotate glenoid cavity superiorly
Retract Scapula
Elevate Scapula
Depress Scapula
Rotate face AWAY from muscle
Remember: Rs Rf RED
Nerve
Spinal Accessory N
Latissimus Dorsi M.
Origin: (5)
Insertion:
Action: (4)
Nerve
Origin
SP of T6-T12, Ribs 9-12, Iliac crest, SP of L1-L5, Median Sacral crest via thoracolumbar fascia
Insertion
Intertubercular Groove of Humerus
Action
Rotate Glenoid Cavity Inferiorly
Extend Humerus
ADduct humerus
Medially Rotate Humerus
REMEBER: RiEAM
Nerve
Thoracodorsal N.
All of the muscles of layer 2, which include rhomboids minor, rhomboids major, and levator scapula are innervated by what nerve?
Dorsal Scapular N.
Rhomboid Major M
Origin:
Insertion:
Action: (3)
Nerve:
Origin
SP of T2-T5
Insertion
Medial border of scapula inferior to sacral spine
Action
Elevate Scaupla
Retract Scapula
Rotate glenoid cavity inferiorly
Nerve
Dorsal Scapular N.
Rhomboid Minor M
Origin: (2)
Insertion:
Action: (3)
Nerve:
Origin
SP of C7-T1 and lower part of ligamentum nuchae (previously supraspinatus)
Insertion
Medial border of scapula at scapular spine
Action
Elevate scapula
Retract scapula
Rotate glenoid cavity inferiorly
Nerve
Dorsal Scapular N.
Levator Scapula M.
Origin:
Insertion:
Action: (3)
Nerve:
Origin
Transverse process of C1-C4
Insertion
Medial border of scapula superior to scapular spine
Action: (3)
Elevate Scapula
Rotate glenoid cavity inferiorly
Laterally rotate neck
Nerve:
Dorsal Scapular N.
The following back muscles of layer 2 can rotate the glenoid cavity inferiorly like the Lats, as well as elevate the scapula like the trapezius. However, all but one of the muscles below is able to retract the scapula. What muscle is unable to retract the scapula?
A. Rhomboids Major M.
B. Rhomboids Minor M.
C. Levator Scapulae M.
Levator Scapulae M.
Serratus Posterior Superior M.
Origin: (2)
Insertion
Action
Nerve
Origin
Nuchal L. and SP of C7-T3
Insertion
Ribs 2-4 on superior part
Action
Elevate ribs during inspiration
Nerve
Intercostal N.
Serratus Posterior Inferior M.
Origin
Insertion
Action
Nerve
Origin
SP of T11-L2
Insertion
Ribs 8-12 on inferior surface
Action
Depress ribs during expiration
Nerve
Anterior Rami (T9-T12)
Both SErratus Posterior Superior and Splenius Capitis originate from what vertebrae?
Spinous process of C7-T3
Splenius Capitis M.
Origin: (2)
Insertion: (2)
Action: Bilaterally vs. Unilaterally
Nerve:
Origin
SP of C7-T3 and Lower 1/2 of Nuchal L.
Insertion
Mastoid Process and Nuchal Line
Action
Bilatteraly: Extend Neck
Unilaterally: Laterally flex neck and Rotate Face toward muscle
Nerve
Posterior Rami (C1-3)
Splenius Cervicis M.
Action and Innvervation is the same as Splenius Capitis
Origin
Insertion
Origin
SP of T3-6
Insertion
Transverse process of C1-3
Action
Bilatteraly: Extend Neck
Unilaterally: Laterally flex neck and Rotate Face toward muscle
Nerve
Posterior Rami (C5-7)
Layer 5 of the deep back muscles has 3 main muscle groups called the Erector Spinae. They all have the same action and innervation. What are these actions and innervations?
Action: (bilateral vs. unilateral)
Nerve:
Action
Bilaterally: Maintiain erect posture and extend vertebral column
Unilaterally: Laterally flex vertebral column
Nerve
Posterior Rami
Going from lateral to medial, what are the 3 groups of erector spinae muscles?
Iliocostalis
Longissimus
Spinalis
Remeber: I Love Spine
Which of the following muscles of the erector spinae is the only one with an associated lumborum muscle, but DOES NOT have an associated capitis muscle?
Iliocostalis M.
T/F: Longissimus Muscles including Thoracis, Cervicis, and Capitis originate mostly from the Transverse process of vertebrae, while spinalis sits mainly on the Spinous process
True
Layer 6 of the deep back muscles are Transversospinalis Group and are all innverated by what?
Posterior Rami
The Semispinalis M. originates from the _________ of vertebrae and all act to ______ spine and _______ the spine ______ from the muscle
Semispinalis Thoracis M.
Semispinalis Cervicis M.
Semispinalis Capitis M.
The Semispinalis M. originates from the Transverse process of vertebrae and all act to extend spine and rotate the spine away from the muscle
Which of the following correctly characterises the Multifidus M. extension from transverse process to spinous process? Where is the multifidus best developed?
A. 1 spinal segment
B. 2 spinal segments
C. 3-4 spinal segments
D. 5 or more spinal segments
3-4 spinal segments
Lumbar region
What is the difference between back sprain and back strain?
Sprain: Relates to ligament damage usually from lack of stretching prior to activity
Strain: relates to muscle damage from excessive stressing
What are the borders of the suboccipital triangle?
What are the contents within the triangle?
What nerve travels around the triangle?
Borders
Rectis Capitis Posterior Major M.
Obliquus Capitis Inferior M.
Obliquuis Capitis Superior M.
Contents
Vertebral A. and Suboccipital N.
Greater Occipital nerve travels around it
Below are some deep muscles not exclusively associated with a back layer. All of the following are innervated by the posterior rami, except for which one which is instead innervated by the posterior portion of posterior rami and the anterior portion of the anterior rami?
A. Interspinalis M.
B. Intertransversearii M.
C. Levator Costorum Longus M.
D. Levator Costorum Brevis M.
Intertransversearii M.
