Muscles of the Back

Trapezius

Latisimus dorsi

Both superficial extrinsic

Levator scapulae

Rhomboid Minor

Rhomboid Major

superficial extrinsic

Serratus Posterior Superior (Deep to Rhomboids) (C7-T2)

Serratus Posterior Inferior (Deep to Latissimus) (T11-L2)

Action and innervation of Both Serattus muscles

Role in Respiration
• Elevate Ribs (SPS)
• Depress Ribs (SPI)
Proprioceptive Function

Innervation
Intercostal Nerves
(Anterior Rami of Spinal Nerves)

What part of the spinal column innervates with Intrinsic deep back muscles

The posterior Rami

Name the two neck muscles

Splenius Capitus (inserts on the mastoid procces)
Splenius Cervicis (Inserts C1-C3)

Action of Splenius Muscles

Action:

Lateral Flexion of Neck

Rotate Head

Extend Head and Neck

Splenius Cervicis Insertion

C1-C3

Splenius Capitus insertion

Mastoid process

List the order of depth for the three groups of spinal muscles, superficial to deep

Erector Spinae

Transversospinales Group

Segmental Group

Iliocostalis

Longissimus

Spinalis

I LIKE STANDING (Erector spinae muscles)

Insertions of erector spinae group

Ribs (iliocostalis)

Transverse Processes (longissimus)

Spinous Processes (spinalis)

Origin of Erector Spinae group

Origin

Spinous Processes: Lumbar Vertebrae

Sacrum

Iliac Crest

What muscle group has orgins here?

Erector Spinae, iliac crest, sacrum, spinous process

Name all the muscles in the Transversospinales group

Semispinales

Multifidus

Rotatores

Name all the muscles in the Segmental Group

interspinales

Intertransversarii

Levatores Costarum

What is the Origin and insertion of the whole transversospinalis group

Origin: Transverse Process

Insertion: Spinous Process

Name the three muscles and how many segments are spanned by each

Semispinalis (4-6 Segments)

Multifidus (2-4 Segments)

Rotatores (1-2 Segments)

Semispinalis 4-6

Multifidus 2-4

Rotatores 1-2

Muscles of segmental group

Interspinales

Intertransversarii*

Levator Costarum

Innervation of Segmental group

Interspinales + Levator Costarum → Posterior Rami

Intertransversarii* → Anterior Rami