Anatomy by Planes
Complex Joints Motions
Transverse plane.
Transverse thoracic, T9.
Facet joints T1 - L1.
Intervertebral symphyses T1 - L1.
35 degrees left rotation.
35 degrees right rotation.
Indirect Motion Reciprocal Relationships ¶: left and right sides
C6 - L1.
Transverse rib cage, T12.
Transverse shoulder girdle, T13. ¶
Transverse rib cage, T12.
Transverse cervical, T10.
Transverse thoracis, T9. ←
Transverse lumbar, T8.
Muscle Multi-Complex (it moves) Depth of Muscle
Right rotation (ipsilateral).
Latissimus dorsi (right-side).
Shoulder.
Shoulder girdle.
Rib cage.
Thoracic. ←
Lumbar.
Level 1 (deep to the skin).
Single-Complex Antagonists (3) Multi-Complex Synergists (5) Multi-Complex Antagonists (6)
Multifidus (thoracic part, left-side).
Rotatores thoracis (left-side).
Semispinalis thoracis (left-side).
Multifidus (thoracic part, right-side).
Rotatores thoracis (right-side).
Semispinalis thoracis (right-side).
External oblique (left-side).
Iliocostalis lumborum (lumbar & thoracic parts, right-side).
Internal oblique (right-side).
Rectus abdominis (left-side).
Transverse abdominis (upper part, right-side).
External oblique (right-side).
Iliocostalis lumborum (lumbar & thoracic parts, left-side).
Internal oblique (left-side).
Latissimus dorsi (left-side).
Rectus abdominis (right-side).
Transverse abdominis (upper part, left-side).
Traditional Anatomy
Inferior attachment
The latissimus attaches to the spinous processes of the lumbar1 and lower six thoracic vertebrae, the sacrum1, and the posterior surface of the iliac crest and blends with the posterior layer of the thoracolumbar fascia. The thoracolumbar fasciae relationship is described in more detail by, among others, Bogduk, Grays, and Stecco.
Its horizontal fibers connect with the inferior angle of the scapula. Its vertical or anterior fibers connect with the lower three to four ribs.
Because of its origins, some references refer to a scapular, a costal, a vertebral, and an iliac part of the latissimus dorsi.
Superior attachment
It connects with the humerus, anterior to the attachment of the teres major. Its vertical fibers attach highest on the humerus, its horizontal fibers lowest, and the oblique ones in between.
Location
This large, triangle-shaped muscle covers most of the lower and mid back. Its thoracic attachment is covered by the trapezius. It runs up and out, converging to a narrow, strong tendon. Its upper fibers run almost horizontally, its middle fibers oblique, and its lower or anterior fibers are nearly vertical.
Innervation
Thoracodorsal nerve.
Vascular Supply
Thoracodorsal atery.
Motion
Depression of the ribs.
Depression of the shoulder girdle.
Adduction, extension, and medial rotation of the shoulder.
