Podcast
Questions and Answers
What is the primary action of the Splenius Capitus muscle?
What is the primary action of the Splenius Capitus muscle?
Which part of the Erector Spinae group is located most laterally?
Which part of the Erector Spinae group is located most laterally?
From where do the Erector Spinae muscles originate?
From where do the Erector Spinae muscles originate?
Which muscle inserts on the post tubercles of the transverse processes of C1-C4?
Which muscle inserts on the post tubercles of the transverse processes of C1-C4?
Signup and view all the answers
What is the innervation for the Splenius muscles?
What is the innervation for the Splenius muscles?
Signup and view all the answers
Which type of muscle primarily acts on the spine and is usually deeper in location?
Which type of muscle primarily acts on the spine and is usually deeper in location?
Signup and view all the answers
What is the main action of the Serratus posterior superior muscle?
What is the main action of the Serratus posterior superior muscle?
Signup and view all the answers
Which of the following muscles is NOT classified as a posterior extrinsic muscle?
Which of the following muscles is NOT classified as a posterior extrinsic muscle?
Signup and view all the answers
What is the innervation of the Serratus posterior inferior muscle?
What is the innervation of the Serratus posterior inferior muscle?
Signup and view all the answers
Which intermediate extrinsic muscle is primarily responsible for respiratory functions?
Which intermediate extrinsic muscle is primarily responsible for respiratory functions?
Signup and view all the answers
What is the role of the superficial anterior extrinsics in relation to the trunk?
What is the role of the superficial anterior extrinsics in relation to the trunk?
Signup and view all the answers
Which of the following structures does NOT typically serve as an origin for the Serratus posterior superior muscle?
Which of the following structures does NOT typically serve as an origin for the Serratus posterior superior muscle?
Signup and view all the answers
The action of the Serratus posterior inferior muscle primarily involves which movement?
The action of the Serratus posterior inferior muscle primarily involves which movement?
Signup and view all the answers
Which muscle group primarily aids in lateral flexion of the spine?
Which muscle group primarily aids in lateral flexion of the spine?
Signup and view all the answers
What is the role of levator costarum during respiration?
What is the role of levator costarum during respiration?
Signup and view all the answers
Which of the following best describes the interspinales muscles?
Which of the following best describes the interspinales muscles?
Signup and view all the answers
What is NOT a function of the anterior muscles of the vertebral column?
What is NOT a function of the anterior muscles of the vertebral column?
Signup and view all the answers
Which of the following is true regarding thoracolumbar fascia?
Which of the following is true regarding thoracolumbar fascia?
Signup and view all the answers
Which of the following actions is NOT attributed to the actions of back muscles?
Which of the following actions is NOT attributed to the actions of back muscles?
Signup and view all the answers
What is the primary attachment point for the levator costarum muscles?
What is the primary attachment point for the levator costarum muscles?
Signup and view all the answers
Which structure provides biomechanical support during movements of the trunk?
Which structure provides biomechanical support during movements of the trunk?
Signup and view all the answers
What is the primary action of the Semispinalis muscle group?
What is the primary action of the Semispinalis muscle group?
Signup and view all the answers
Which of the following muscles spans 2-4 vertebral segments?
Which of the following muscles spans 2-4 vertebral segments?
Signup and view all the answers
What is the innervation of the Rotatores muscle?
What is the innervation of the Rotatores muscle?
Signup and view all the answers
What is the origin of the Multifidus muscle?
What is the origin of the Multifidus muscle?
Signup and view all the answers
Which muscle is responsible for aiding in proprioception?
Which muscle is responsible for aiding in proprioception?
Signup and view all the answers
Which of the following origins does the Semispinalis muscle NOT have?
Which of the following origins does the Semispinalis muscle NOT have?
Signup and view all the answers
How many vertebral segments does the Rotatores muscle span?
How many vertebral segments does the Rotatores muscle span?
Signup and view all the answers
What stabilizing role does the Multifidus muscle play?
What stabilizing role does the Multifidus muscle play?
Signup and view all the answers
What is the primary action of the Iliocostalis muscle?
What is the primary action of the Iliocostalis muscle?
Signup and view all the answers
Which muscle is responsible for laterally flexing the trunk unilaterally?
Which muscle is responsible for laterally flexing the trunk unilaterally?
Signup and view all the answers
Which of the following correctly describes the innervation for the Longissimus muscle?
Which of the following correctly describes the innervation for the Longissimus muscle?
Signup and view all the answers
Where do the Iliocostalis muscles originate?
Where do the Iliocostalis muscles originate?
Signup and view all the answers
What action does the Spinalis muscle primarily perform bilaterally?
What action does the Spinalis muscle primarily perform bilaterally?
Signup and view all the answers
Which anatomical structure does the Longissimus muscle insert into?
Which anatomical structure does the Longissimus muscle insert into?
Signup and view all the answers
Which of the following actions does the Longissimus muscle NOT perform?
Which of the following actions does the Longissimus muscle NOT perform?
Signup and view all the answers
What is one of the actions regulated by the Iliocostalis muscle during its eccentric contraction?
What is one of the actions regulated by the Iliocostalis muscle during its eccentric contraction?
Signup and view all the answers
Study Notes
Overview of Trunk Muscles
- Trunk muscles categorized by function and layering: intrinsic (deep, spinal action) and extrinsic (superficial, upper limb or respiratory action).
Posterior Extrinsic Muscles
- Superficial Posterior Extrinsics: Connect vertebral column to upper extremities; names include Trapezius, Latissimus dorsi, Rhomboids, and Levator scapula.
- Intermediate Extrinsics: Connect vertebral column to ribs; include Serratus posterior superior (elevates ribs) and Serratus posterior inferior (depresses ribs).
Intrinsic Muscles
-
Erector Spinae: Arises from the thoracolumbar fascia; three main subdivisions:
- Iliocostalis: Lateral group, subdivided into Lumborum, Thoracis, Cervicis.
- Longissimus: Middle group, subdivided into Thoracis, Cervicis, Capitus.
- Spinalis: Medial group, subdivided into Thoracis, Cervicis, Capitus.
Deep Intrinsics
-
Transversospinal Muscles:
- Semispinalis: Spans 4-6 vertebral segments; includes thoracis, cervicis, capitus variations.
- Multifidus: Spans 2-4 segments; stabilizes the spine.
- Rotatores: Spans 1-2 segments; aids in stabilization and proprioception.
Actions of Back Muscles
- Muscles perform various actions including extension, contralateral rotation, and lateral flexion.
- Eccentric actions are critical in functional activities, controlling movement dynamics.
Thoracic Cage and Intercostal Muscles
- Intercostal Muscles: External and internal groups contribute to respiration and trunk stability.
Anterior Muscles of the Vertebral Column
- Prevertebral muscles discussed later in relation to the neck and abdominal wall.
Thoracolumbar Fascia
- Composed of multiple connective tissue layers:
- Superficial Layer: Contains subcutaneous tissue and adipose tissue; connects to deep fascia.
- Deep Layer: Represents the thoracolumbar fascia proper, critical for supporting the lumbar region.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on the anatomy of the Splenius Capitus muscle, including its origin, insertion, action, and innervation. This quiz will help you understand the muscle's role in lateral flexion and ipsilateral rotation. Perfect for anatomy students!
