6.2 Muscles of the Back

Muscles of the Back

• The back muscles are divided into three main categories:

  1. Superficial

  2. Intermediate

  3. Deep

Superficial Muscles

• Function: Associated with shoulder movement

• Key Muscles:

  • Trapezius:

  • Contains three parts:

    • Transverse part

    • Descending part

    • Ascending part

  • Latissimus Dorsi:

  • Cut version noted in highlighted diagrams

Intermediate Muscles

• Function: Associated with trunk movement

• Key Muscles:

  • Rhomboid Major

  • Rhomboid Minor

  • Serratus Posterior Superior

  • Serratus Posterior Inferior

Deep Muscles

• Function: Associated with movement of the vertebral column

• Key Muscles:

  • Erector Spinae Muscles:

  • Iliocostalis

  • Longissimus

  • Spinalis

    

Extra notes

Detailed Functions and Anatomy of Muscles

• Erector Spinae Muscles Subgroups:

  • Iliocostalis: Located laterally

  • Longissimus: Central position of erector spinae

  • Spinalis: Medially positioned

Minor Deep Intrinsic Muscles

• Interspinales: Stabilizes the spinal column

• Intertransversarii: Also stabilizes the spinal column

• Levatores Costarum: Elevates the ribs

• Rotatores:

  • Stabilizes spinal column and important for proprioception

Notable Attachments and Structures

• Thoracolumbar Fascia: Deep layer of nuchal fascia

• Connections include:

  • Clavicle

  • Acromion

  • Medial border of the scapula

  • Iliac crest

  • Lumbar triangle with internal/external obliques

Diagram Highlights

• Notable diagrams showing muscle positions, including deep structures like the spinalis and spasm of the trapezius.

• Positions of muscles such as Splenius Capitis and Cervicis, seen prominently in lateral views of the back.

Summary

Understanding the back muscles is essential for comprehending their functions in movement, stability, and posture. The complexity of these muscles indicates their crucial role in athletic performance and physiotherapy.