WEEK 11 (Muscles of back) Flashcards
Which muscles are Extrinsic muscles?
Muscles in the SUPERFICIAL and INTERMEDIATE groups
Muscles of the back and organised into which groups?
- Superficial
- Intermediate
- Deep
What are the characteristics of extrinsic muscles?
- Innervated by anterior rami of spinal nerves
- SUPERFICIAL GROUP consists of muscles related to and involved in movements of the UPPER LIMB
- INTERMEDIATE GROUP consists of muscles attached to RIBS & serve a RESPIRATORY FUNCTION
Which muscles are Intrinsic muscles?
Muscles of the DEEP group are INTRINSIC MUSCLES
[Innervated by the posterior rami of spinal nerves and are directly related to movements of the vertebral column and head]
What are the properties of the Superficial group of back muscles?
- Immediately deep to the skin and superficial fascia
- Attach superior appendicular skeleton (clavicle, scapula & humerus) to the axial skeleton
- Also called the APPENDICULAR GROUP
- Muscles include TRAPEZIUS, LATISSIMUS DORSI, RHOMBOID MAJOR, RHOMBOID MINOR and LEVATOR SCAPULAE
What is the function of the Trapezius/
Elevates the scapula
Where does the blood supply of the trapezius come from?
- SUPERFICIAL BRANCH OF THE TRANSVERSE CERVICAL ARTERY
- ACROMIAL BRANCH OF THE SUPRASCAPULAR ARTERY
- DORSAL BRANCHES OF POSTERIOR INTERCOSTAL ARTERIES
What is the function of the Latissmus dorsi?
- Extension
- Adduction
- Medial rotation of the upper limb
- Depresses shoulder preventing its upward movement
Where does the blood supply of the Latissimus dorsi come from?
- THORACODORSAL ARTERY (primary blood supply)
- Small arteries from DORSAL BRANCHES of POSTERIOR INTERCOSTAL and LUMBAR ARTERIES
What are the functions of the Levator Scapulae muscle?
- Elevates the scapula
- Assists other muscles in rotating the lateral aspect of the scapula inferiorly
Where does the blood supply of the Levator scapulae come from?
Branches from the TRANSVERSE and ASCENDING CERVICAL ARTERIES
What is the function of the Rhomboid minor & major?
The two rhomboid muscles work together to retract or pull the scapula toward the vertebral column
Which muscles are the Intermediate group of back muscles?
SERRATUS POSTERIOR SUPERIOR & SERRATUS POSTERIOR INFERIOR
[two thin muscular sheets in the superior & inferior regions of the back & positioning suggests a respiratory function]
Which muscles are Deep group muscles?
- SPLENIUS CAPITIS & CERVICIS (SPINOTRANSVERSALES)
- ERECTOR SPINAE & TRANSVERSOSPINALES
- INTERSPINALES & INTERTRANSVERSAARII
What us unique about the Semispinalis Capitis?
It attaches to the skull
BILATERAL CONTRACTION pulls the head posteriorly whereas UNILATERAL CONTRACTION pulls the head posteriorly and turns it causing the CHIN to move SUPERIORLY and turn towards the side of the contracting muscle
