Chapter: 7, 8, 11 Flashcards
What bones does the pectoral girdle encompass?
- S-shaped clavicle/ collarbone
- Scapula/ shoulder blade
How does the clavicle connect with the pectoral girdle?
- The clavicle articulates with the sternum’s manubruim; is the only direct connection between the axial skeleton and the pectoral girdle
How does the scapula connect with the pectoral girdle?
The scapula is attached to the clavicle anteriorly but has no connection to the actual axial skeleton; instead skeletal muscles and ligaments support it.
What is the only bone that attaches to the arm?
The clavicle
What kind of bone is the clavicle?
A long bone
How do you identify position of the clavicle you are holding?
- Rounded end of the clavicle comes to sternum
- Flat end faces the outside of the body
- Roughness on the bone is on the bottom
- Smoothness on the bone is on the top
- The bone sticks out anteriorly and curves back posteriorly
What is a fossa?
Where muscle attaches
What do ligaments do?
Connects bone to bone
Muscles associated with the pectoral girdle and upper limbs can be divided into four groups:
- Muscles that position the pectoral girdle***
- Muscles that move the arm***
- Muscles that move the forearm and hand
- Muscles that move the hand and fingers
The movements involving trapezius positioning the pectoral girdle
- elevation and depression
- Retract upwards (trap pulls on scapula to rotate)
The movements involving rhomboideus positioning the pectoral girdle
- Adduction
- Downward/ medial rotation
The movements involving lever scapulae positioning the pectoral girdle
- Elevates scapula
The posterior muscles that position the pectoral girdle
- Trapezius
- Rhomboideus
- lever scapulae
The anterior muscles that position the pectoral girdle
- Pectoralis Minor
- Serratus anterior
- Subclavious
The movements involving the pectorals minor positioning the pectoral girdle
- Depression
- Protraction
- Downwards rotation
The movements involving the serratus anterior in positioning the pectoral girdle
- Protraction
- Upward rotation
The movements involving the subclavious in positioning the pectoral girdle
- Pulls forward
- Depression
Origin of levator scapulae
Transverse processes of first four cervical vertebrae
Insertion of the levator scapulae
Action of the levator scapulae
Elevates scapula
Innervation of the scapula
Cervical nerves
Cy-C, and dorsal scapular nerve (Cs)
Origin of pectoralis minor
Anterior surfaces and superior margins of ribs 3-5 or 2-4 and the fascia covering the associated external intercostal muscles
Insertion of pectoralis minor
Coracoid process of scapula
Action of the pectoralis minor
Depresses and protracts shoulder; rotates scapula so glenoid cavity moves inferiorly (downward rotation); elevates ribs if scapula is stationary
Innervation of pectoralis minor
Medial pectoral nerve (G,, T,)
Origin of the rhomboid major
Ligamentum nuchae and the spinous processes of vertebrae T2 to T5
Insertion of the rhomboid major
Vertebral border of scapula from spine to inferior angle
Action of the rhomboid major
Adducts and performs downward rotation of the scapula
Innervation of the rhomboid major
Dorsal scapular nerve (C5)
Origin of the rhomboid minor
Spinous processes of vertebrae C2 - T1
Insertion of the rhomboid minor
Vertebral border of scapula
Action of the rhomboid minor
Adducts and performs downward rotation of the scapula
Innervation of the rhomboid minor
Dorsal scapular nerve (C5)
Origin of serratus anterior
Anterior and superior margins of ribs
1-8, 1-9, or 1-10
Insertion of serratus anterior
Anterior surface of vertebral border of scapula
Action of the serratus anterior
Protracts shoulder; rotates scapula so glenoid cavity moves superiorly (upward rotation)
Innervation of the serratus anterior
Long thoracic nerve (C5 - C7)
Origin of the subclavius
First rib
Insertion of the subclavius
Clavicle (inferior border of middle 1/3)
Action of the subclavius
Depresses and protracts shoulder
Innervation of the subclavius
Nerve to subclavius (C5 - C6)
Origin of the trapezius
Occipital bone, ligamentum nuchae, and spinous processes of thoracic vertebrae
Insertion of the trapezius
Clavicle and scapula (acromion and scapular spine)
Action of the trapezius
Depends on active region and state of other muscles; may elevate, retract, depress, or rotate scapula upward and/or clavicle; can also extend neck when the position of the shoulder is fixed
Innervation of the trapezius
Accessory nerve (XI)
