Back Myology Flashcards
Trapezius M. (Layer 1)
Occipital Bone; Ligamentum Nuchae; Spinous Processes C7-T12, Occipital Bone
Lateral 1/3 Clavicle; Acromion; Scapular Spine of Scapula
Retract, Elevate, & Depress the Scapula; Neck Extension (Bilaterally); Neck Lateral Flexion & Rotate Face Away (Unilaterally)
Spinal Accessory N. (CN XI)
Latissimus Dorsi M. (Layer 1)
Spinous Processes T6-L5 & Median Sacral Crest; Ribs 9-12; Iliac Crest
Floor of Humeral Intertubercular Groove
Extend, Adduct, & Medially/Internally Rotate Humerus; Rotate Glenoid Cavity Inferiorly
Thoracodorsal N. (C6-8)
Rhomboid Major M. (Layer 2)
Spinous Processes T2-T5
Medial Border of Scapula (Inferior to Scapular Spine)
Retract/Elevate Scapula; Rotate Glenoid Cavity Inferiorly
Dorsal Scapular N. (C4,5)
Rhomboid Minor M. (Layer 2)
Spinous Processes C7-T1
Medial border of scapula (at scapular spine)
Retract/Elevate Scapula; Rotate Glenoid Cavity Inferiorly
Dorsal Scapular N. (C4,5)
Levator Scapulae M. (Layer 2)
Transverse Processes C1-C4
Medial border of scapula (Superior to scapular spine)
Elevate Scapula; Rotate Glenoid Cavity Inferiorly; Extend and Laterally Flex Neck
Dorsal Scapular N. (C5)
Serratus Posterior Superior M. (Layer 3)
Nuchal L. and Spinous Processes C7-T3
Superior surface of ribs 2-4
Elevate Ribs with Forced Inspiration (Proprioceptive)
Intercostal N. (2-5)
Serratus Posterior Inferior M. (Layer 3)
Spinous Processes T11-L2
Inferior Surface Ribs 8-12
Depress Ribs with Forced Expiration (Proprioceptive)
Anterior Rami (T9-12)
Splenius Capitus M. (Layer 4)
Lower 1/2 Ligamentum Nuchae & Spinous Processes C7-T3
Mastoid Process; Lateral 1/3 Superior Nuchal Line
Extend Neck (Bilaterally); Laterally Flex Neck & Rotate Face Toward (Unilaterally)
Posterior Rami
Splenius Cervicis M.
Spinous Process T3-T6
Transverse Process C1-C3
Extend Neck (Bilaterally); Laterally Flex Neck and Rotate Face Towards (Unilaterally)
Posterior Rami
Erector Spinae Group (Layer 5)
- Iliocostalis (Lateral)
- Iliocostalis Lumborum M.
- Iliocostalis Thoracis M.
- Iliocostalis Cervicis M.
- Longissimus (Intermediate)
- Longissimus Thoracis M.
- Longissimus Cervicis M.
- Longissimus Capitis M.
- Spinalis (Medial)
- Spinalis Thoracis M.
- Spinalis Cervicis M.
- Maintain erect posture; Extend vertebral column and head (Bilaterally); Laterally flex vertebral column (unilaterally)
- Segmentally innervated by Posterior Rami of Spinal Nerves
Transversospinalis Group (Layer 6)
- Semispinalis Group (5+ Segments)
- Semispinalis Thoracis M.
- Semispinalis Cervicis M.
- Semispinalis Capitis M.
- Multifidus M. (3-4 Segments)
- Rotatores Longus M. (2 Segments)
- Rotatores Brevis M. (1 Segment)
- A: Extend Spine; Rotate Spine Away
- Exception: Semispinalis Capitis - Extend Head; Rotate Face Away
- N: Posterior Rami
Interspinalis M.
Extend Spine
Posterior Rami
Intertransversarii M.
Laterally Flex Spine
Posterior Portion (Posterior Rami); Anterior Portion (Anterior Rami)
Levator Costarum Longus M.
Transverse Processes C7-T11
2nd Rib Inferior to Origin
Elevate Ribs
Posterior Rami
Levator Costarum Brevis M.
Transverse Processes C7-T11
Adjacent Rib Inferior To Origin
Elevate Ribs
Posterior Rami