Podcast
Questions and Answers
What is the function of the suspensory ligaments of Cooper in the breast?
What is the function of the suspensory ligaments of Cooper in the breast?
- They connect the mammary glands to the dermis. (correct)
- They provide structural support to the ribs.
- They supply blood to the breast tissue.
- They facilitate the drainage of lymph nodes.
Which structure is part of the anatomy of the breast that opens independently on the nipple?
Which structure is part of the anatomy of the breast that opens independently on the nipple?
- Retro-mammary space
- Lactiferous ducts (correct)
- Areola
- Lobules of glandular tissue
The areola is characterized as what type of anatomical feature in the breast?
The areola is characterized as what type of anatomical feature in the breast?
- An adipose tissue layer
- A glandular lobe
- A ductal opening
- A circular pigmented area (correct)
What is the role of the retro-mammary space in relation to the breast?
What is the role of the retro-mammary space in relation to the breast?
Which arteries provide blood supply to the medial mammary branches?
Which arteries provide blood supply to the medial mammary branches?
Which lymph nodes drain most lymph from the breast?
Which lymph nodes drain most lymph from the breast?
At what point do significant changes in breast tissue begin to occur?
At what point do significant changes in breast tissue begin to occur?
What hormones stimulate breast tissue proliferation during pregnancy?
What hormones stimulate breast tissue proliferation during pregnancy?
What is a characteristic of post-menopausal breasts?
What is a characteristic of post-menopausal breasts?
Which method is NOT involved in the spread of breast cancer?
Which method is NOT involved in the spread of breast cancer?
Which statement about breast cancer in men is accurate?
Which statement about breast cancer in men is accurate?
What forms the inlet of the axilla?
What forms the inlet of the axilla?
Which muscle is primarily responsible for pulling the tip of the shoulder down?
Which muscle is primarily responsible for pulling the tip of the shoulder down?
What are the primary actions of the pectoralis major muscle?
What are the primary actions of the pectoralis major muscle?
Which structure is not part of the anterior wall of the axilla?
Which structure is not part of the anterior wall of the axilla?
What is the primary action of the clavicular head of the pectoralis major?
What is the primary action of the clavicular head of the pectoralis major?
Which nerve is primarily responsible for the function of the serratus anterior?
Which nerve is primarily responsible for the function of the serratus anterior?
Which muscle is NOT involved in medial rotation of the arm?
Which muscle is NOT involved in medial rotation of the arm?
What condition is characterized by the medial border of the scapula moving laterally and posteriorly?
What condition is characterized by the medial border of the scapula moving laterally and posteriorly?
Which muscle primarily participates in the extension of the arm?
Which muscle primarily participates in the extension of the arm?
Which of the following muscles is associated with the upper and lower subscapular nerve?
Which of the following muscles is associated with the upper and lower subscapular nerve?
Which artery is associated with the branches that supply the pectoral muscles?
Which artery is associated with the branches that supply the pectoral muscles?
Which action is primarily performed by the serratus anterior muscle?
Which action is primarily performed by the serratus anterior muscle?
What is the primary function of the muscles of the pectoral girdle?
What is the primary function of the muscles of the pectoral girdle?
Which structures are contained within the axilla?
Which structures are contained within the axilla?
What are the mammary glands classified as?
What are the mammary glands classified as?
What happens to the mammary glands during pregnancy?
What happens to the mammary glands during pregnancy?
What is the vertical extent of the female breast?
What is the vertical extent of the female breast?
Which muscle borders the lateral aspect of the female breast?
Which muscle borders the lateral aspect of the female breast?
What is the main role of the brachial plexus?
What is the main role of the brachial plexus?
What does the superior margin of the teres major indicate?
What does the superior margin of the teres major indicate?
Which artery does NOT arise from the axillary artery?
Which artery does NOT arise from the axillary artery?
Which nerve innervates the diaphragm?
Which nerve innervates the diaphragm?
What is the main function of the long thoracic nerve?
What is the main function of the long thoracic nerve?
Which group of lymph nodes is NOT part of the axillary lymphatic drainage?
Which group of lymph nodes is NOT part of the axillary lymphatic drainage?
What structure separates the three parts of the axillary artery?
What structure separates the three parts of the axillary artery?
Which artery is not part of the second part of the axillary artery?
Which artery is not part of the second part of the axillary artery?
What is the primary function of the axillary nerve?
What is the primary function of the axillary nerve?
Which of the following does NOT pass through the axilla?
Which of the following does NOT pass through the axilla?
Which structure is innervated by the inferior subscapular nerve?
Which structure is innervated by the inferior subscapular nerve?
What is the role of the medial cutaneous nerve?
What is the role of the medial cutaneous nerve?
What contributes to the formation of the brachial plexus?
What contributes to the formation of the brachial plexus?
What is the innervation of the medial pectoral nerve?
What is the innervation of the medial pectoral nerve?
What percentage of lymph from the breast typically drains to axillary lymph nodes?
What percentage of lymph from the breast typically drains to axillary lymph nodes?
What occurs in breast tissue during puberty?
What occurs in breast tissue during puberty?
Which lymph nodes also drain lymph from the breast aside from the axillary nodes?
Which lymph nodes also drain lymph from the breast aside from the axillary nodes?
How do breasts typically change in size and shape for women who are multiparous?
How do breasts typically change in size and shape for women who are multiparous?
What happens to the breast tissue post-menopause?
What happens to the breast tissue post-menopause?
What anatomical feature connects the mammary glands to the dermis?
What anatomical feature connects the mammary glands to the dermis?
Which structure acts as a buffer between the breast and the deep pectoral fascia?
Which structure acts as a buffer between the breast and the deep pectoral fascia?
How many lobules of glandular tissue are typically found in the breast?
How many lobules of glandular tissue are typically found in the breast?
What is the main function of the lactiferous sinus in the breast?
What is the main function of the lactiferous sinus in the breast?
Which arteries primarily supply blood to the lateral mammary branches?
Which arteries primarily supply blood to the lateral mammary branches?
What is the action of the clavicular head of the pectoralis major?
What is the action of the clavicular head of the pectoralis major?
Which nerve primarily innervates the serratus anterior muscle?
Which nerve primarily innervates the serratus anterior muscle?
What is the primary action of the teres major muscle?
What is the primary action of the teres major muscle?
Which structure is associated with the upper and lower subscapular nerve?
Which structure is associated with the upper and lower subscapular nerve?
What happens when the serratus anterior is paralyzed due to long thoracic nerve injury?
What happens when the serratus anterior is paralyzed due to long thoracic nerve injury?
Which muscle is primarily responsible for the protraction and rotation of the scapula?
Which muscle is primarily responsible for the protraction and rotation of the scapula?
Which nerve innervates the latissimus dorsi muscle?
Which nerve innervates the latissimus dorsi muscle?
What is one of the primary functions of the pectoralis major muscle?
What is one of the primary functions of the pectoralis major muscle?
Which of the following correctly describes the structure of the axilla?
Which of the following correctly describes the structure of the axilla?
Which of the following structures is contained within the axilla?
Which of the following structures is contained within the axilla?
What changes occur within the breast during pregnancy?
What changes occur within the breast during pregnancy?
What role does the brachial plexus primarily serve?
What role does the brachial plexus primarily serve?
Which statement best describes the mammary glands?
Which statement best describes the mammary glands?
In terms of vertical extent, from what to what ribs does the female breast typically extend?
In terms of vertical extent, from what to what ribs does the female breast typically extend?
Which muscle primarily borders the lateral aspect of the female breast?
Which muscle primarily borders the lateral aspect of the female breast?
Which condition results from an injury to the inferior parts of the brachial plexus?
Which condition results from an injury to the inferior parts of the brachial plexus?
What is a common presentation of Erb-Duchenne palsy?
What is a common presentation of Erb-Duchenne palsy?
Which muscles are affected by Klumpke palsy due to injury of C8 and T1 fibers?
Which muscles are affected by Klumpke palsy due to injury of C8 and T1 fibers?
What sensory change is typically observed in Klumpke palsy?
What sensory change is typically observed in Klumpke palsy?
Which of the following muscles is NOT part of the rotator cuff group?
Which of the following muscles is NOT part of the rotator cuff group?
Which nerve is associated with the shoulder stabilization function of the supraspinatus muscle?
Which nerve is associated with the shoulder stabilization function of the supraspinatus muscle?
What is the primary action performed by the deltoid muscle?
What is the primary action performed by the deltoid muscle?
What is the mechanism behind the 'waiter's tip position' seen in Erb-Duchenne palsy?
What is the mechanism behind the 'waiter's tip position' seen in Erb-Duchenne palsy?
Which artery is NOT a branch of the second part of the axillary artery?
Which artery is NOT a branch of the second part of the axillary artery?
What structure lies at the inferior margin of the teres major?
What structure lies at the inferior margin of the teres major?
Which nerve innervates both the subscapularis and teres major muscles?
Which nerve innervates both the subscapularis and teres major muscles?
Which group contains lymph nodes that are NOT part of the axillary lymphatic drainage?
Which group contains lymph nodes that are NOT part of the axillary lymphatic drainage?
The lateral cutaneous nerve of the forearm is a branch of which nerve?
The lateral cutaneous nerve of the forearm is a branch of which nerve?
Which structure is located in the triangular space?
Which structure is located in the triangular space?
What separates the three parts of the axillary artery?
What separates the three parts of the axillary artery?
Which root contributes to the phrenic nerve?
Which root contributes to the phrenic nerve?
Which nerve innervates the deltoid muscle?
Which nerve innervates the deltoid muscle?
Which artery is classified as a branch of the third part of the axillary artery?
Which artery is classified as a branch of the third part of the axillary artery?
Which nerve is NOT part of the lateral cord of the brachial plexus?
Which nerve is NOT part of the lateral cord of the brachial plexus?
What is innervated by the medial pectoral nerve?
What is innervated by the medial pectoral nerve?
What anatomical feature forms an extension toward the axillary fossa?
What anatomical feature forms an extension toward the axillary fossa?
Which of the following is true regarding the glandular structure of the breast?
Which of the following is true regarding the glandular structure of the breast?
What is the primary function of the retro-mammary space?
What is the primary function of the retro-mammary space?
Which arteries supply blood to the lateral mammary branches?
Which arteries supply blood to the lateral mammary branches?
What anatomical structure is separate from the breast but serves as a boundary?
What anatomical structure is separate from the breast but serves as a boundary?
Which lymph node group is primarily responsible for draining lymph from most of the breast?
Which lymph node group is primarily responsible for draining lymph from most of the breast?
What physiological changes typically occur in the breasts during pregnancy?
What physiological changes typically occur in the breasts during pregnancy?
In women who have given birth multiple times, how do their breasts typically change?
In women who have given birth multiple times, how do their breasts typically change?
Which type of lymph nodes also plays a role in draining lymph from the breast alongside the axillary nodes?
Which type of lymph nodes also plays a role in draining lymph from the breast alongside the axillary nodes?
What is the typical condition of the breast tissue in post-menopausal women?
What is the typical condition of the breast tissue in post-menopausal women?
What is the primary role of the pectoral girdle muscles?
What is the primary role of the pectoral girdle muscles?
Which ribs define the vertical extension of the female breast?
Which ribs define the vertical extension of the female breast?
Which anatomical structure primarily connects the mammary glands to the overlying skin?
Which anatomical structure primarily connects the mammary glands to the overlying skin?
Which of the following components is part of the brachial plexus?
Which of the following components is part of the brachial plexus?
What occurs to the breast tissue during puberty?
What occurs to the breast tissue during puberty?
Which muscle is primarily responsible for stabilizing the scapula during arm movements?
Which muscle is primarily responsible for stabilizing the scapula during arm movements?
What structural change occurs in mammary glands during pregnancy?
What structural change occurs in mammary glands during pregnancy?
Which structure separates the parts of the axillary artery?
Which structure separates the parts of the axillary artery?
Which muscles are primarily involved in flexion and medial rotation of the arm?
Which muscles are primarily involved in flexion and medial rotation of the arm?
What constitutes the lateral wall of the axilla?
What constitutes the lateral wall of the axilla?
What is the primary role of pectoralis minor?
What is the primary role of pectoralis minor?
Which structures delimit the inlet of the axilla?
Which structures delimit the inlet of the axilla?
Which layer constitutes the floor of the axilla?
Which layer constitutes the floor of the axilla?
What is the primary characteristic of Klumpke palsy?
What is the primary characteristic of Klumpke palsy?
Which nerves are primarily affected in Erb-Duchenne palsy?
Which nerves are primarily affected in Erb-Duchenne palsy?
What is the typical arm position described in a case of Erb-Duchenne palsy?
What is the typical arm position described in a case of Erb-Duchenne palsy?
Which muscle primarily contributes to the abduction of the arm beyond 15 degrees?
Which muscle primarily contributes to the abduction of the arm beyond 15 degrees?
What symptom is commonly associated with Klumpke palsy?
What symptom is commonly associated with Klumpke palsy?
Which anatomical regions are affected by Erb-Duchenne palsy?
Which anatomical regions are affected by Erb-Duchenne palsy?
What is the result of an injury to the inferior trunk branches of the brachial plexus?
What is the result of an injury to the inferior trunk branches of the brachial plexus?
Which of the following describes the action of the supraspinatus muscle?
Which of the following describes the action of the supraspinatus muscle?
Which structure is located superiorly to the teres major muscle?
Which structure is located superiorly to the teres major muscle?
Which artery arises from the second part of the axillary artery?
Which artery arises from the second part of the axillary artery?
The axillary nerve primarily provides motor innervation to which muscle?
The axillary nerve primarily provides motor innervation to which muscle?
What is the primary target of the dorsal scapular nerve?
What is the primary target of the dorsal scapular nerve?
Which terminal branch of the brachial plexus is responsible for innervating the medial compartment of the arm?
Which terminal branch of the brachial plexus is responsible for innervating the medial compartment of the arm?
Which artery supplies blood to the teres major muscle?
Which artery supplies blood to the teres major muscle?
Which group of lymph nodes is primarily responsible for draining lymph from the breast?
Which group of lymph nodes is primarily responsible for draining lymph from the breast?
Which muscle is primarily innervated by the thoracodorsal nerve?
Which muscle is primarily innervated by the thoracodorsal nerve?
Which of the following is NOT a terminal branch of the brachial plexus?
Which of the following is NOT a terminal branch of the brachial plexus?
The brachial plexus is formed by the anterior rami of which spinal nerves?
The brachial plexus is formed by the anterior rami of which spinal nerves?
Which of these structures passes through the axilla?
Which of these structures passes through the axilla?
What does the long thoracic nerve innervate?
What does the long thoracic nerve innervate?
Flashcards
Axilla
Axilla
The armpit, a region between the upper arm and the chest wall.
Brachial Plexus
Brachial Plexus
A network of nerves that arises from the cervical and upper thoracic spinal nerves, supplying the upper limb.
Breast Structure
Breast Structure
Composed of mammary glands, subcutaneous fat for shape, and extends from the 2nd to 6th ribs, laterally from sternum to anterior axillary line.
Mammary Glands
Mammary Glands
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Pectoral Girdle Muscles
Pectoral Girdle Muscles
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Breast Changes (Pregnancy)
Breast Changes (Pregnancy)
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Back Muscles
Back Muscles
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Axillary Artery/Vein
Axillary Artery/Vein
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Lymphatic Drainage
Lymphatic Drainage
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Breast Development
Breast Development
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Breast Changes in Pregnancy
Breast Changes in Pregnancy
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Breast Cancer Spread
Breast Cancer Spread
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Post-Menopausal Breasts
Post-Menopausal Breasts
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Axillary Process
Axillary Process
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Retro-mammary Space
Retro-mammary Space
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Suspensory Ligaments (of Cooper)
Suspensory Ligaments (of Cooper)
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Lactiferous Sinus
Lactiferous Sinus
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What is the difference between a lactiferous duct and a lactiferous sinus?
What is the difference between a lactiferous duct and a lactiferous sinus?
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Axillary Gateway
Axillary Gateway
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Axillary Floor
Axillary Floor
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Pectoralis Minor Muscle
Pectoralis Minor Muscle
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Pectoralis Major Muscle
Pectoralis Major Muscle
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Clavipectoral Fascia
Clavipectoral Fascia
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Clavicular Head Action
Clavicular Head Action
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Sternocostal Head Action
Sternocostal Head Action
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Lateral Pectoral Nerve
Lateral Pectoral Nerve
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Subscapularis Action
Subscapularis Action
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Teres Major Action
Teres Major Action
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Latissimus Dorsi Action
Latissimus Dorsi Action
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Serratus Anterior Action
Serratus Anterior Action
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Winged Scapula
Winged Scapula
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Inferior border of scapula
Inferior border of scapula
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Surgical neck of humerus
Surgical neck of humerus
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Teres major
Teres major
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Long head of triceps brachii
Long head of triceps brachii
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Teres minor
Teres minor
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Axillary artery
Axillary artery
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Roots of brachial plexus
Roots of brachial plexus
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Trunks of brachial plexus
Trunks of brachial plexus
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Divisions of brachial plexus
Divisions of brachial plexus
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Cords of brachial plexus
Cords of brachial plexus
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Terminal branches of brachial plexus
Terminal branches of brachial plexus
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Cutaneous innervation of the upper limb
Cutaneous innervation of the upper limb
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What are the main functions of the Suspensory ligaments?
What are the main functions of the Suspensory ligaments?
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Lymphatic Drainage of the Breast
Lymphatic Drainage of the Breast
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Breast Changes at Puberty
Breast Changes at Puberty
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Breast Changes During Pregnancy
Breast Changes During Pregnancy
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Klumpke Palsy
Klumpke Palsy
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Erb-Duchenne Palsy
Erb-Duchenne Palsy
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What is the 'waiter's tip' position?
What is the 'waiter's tip' position?
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What does 'supinated forearm' mean?
What does 'supinated forearm' mean?
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What are the muscles that make up the rotator cuff?
What are the muscles that make up the rotator cuff?
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What is the function of the Trapezius muscle?
What is the function of the Trapezius muscle?
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What is the function of the Deltoid muscle?
What is the function of the Deltoid muscle?
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What is the difference between Klumpke palsy and Erb-Duchenne palsy?
What is the difference between Klumpke palsy and Erb-Duchenne palsy?
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Inferior margin of the subscapularis
Inferior margin of the subscapularis
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Surgical neck of the humerus
Surgical neck of the humerus
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Superior margin of the teres major
Superior margin of the teres major
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Lateral margin of the long head of the triceps brachii
Lateral margin of the long head of the triceps brachii
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What passes into each space in the posterior shoulder?
What passes into each space in the posterior shoulder?
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Central compartment of the axilla
Central compartment of the axilla
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Apical compartment of the axilla
Apical compartment of the axilla
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First part of the axillary artery
First part of the axillary artery
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Superior thoracic artery
Superior thoracic artery
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Thoracoacromial artery
Thoracoacromial artery
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Lateral thoracic artery
Lateral thoracic artery
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Posterior circumflex artery
Posterior circumflex artery
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Roots of the brachial plexus
Roots of the brachial plexus
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Trunks of the brachial plexus
Trunks of the brachial plexus
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Divisions of the brachial plexus
Divisions of the brachial plexus
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Lactiferous Ducts
Lactiferous Ducts
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Long Thoracic Nerve
Long Thoracic Nerve
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What are the mammary lobules?
What are the mammary lobules?
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Axillary Inlet
Axillary Inlet
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Pectoralis Minor Action
Pectoralis Minor Action
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Pectoralis Major Action
Pectoralis Major Action
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'Waiter's Tip' Position
'Waiter's Tip' Position
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Supinated Forearm
Supinated Forearm
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Rotator Cuff Muscles
Rotator Cuff Muscles
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Trapezius Muscle Function
Trapezius Muscle Function
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Deltoid Muscle Function
Deltoid Muscle Function
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Difference between Klumpke and Erb-Duchenne Palsy
Difference between Klumpke and Erb-Duchenne Palsy
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Inferior Margin of Subscapularis
Inferior Margin of Subscapularis
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Superior Margin of Teres Major
Superior Margin of Teres Major
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Lateral Margin of Long Head of Triceps Brachii
Lateral Margin of Long Head of Triceps Brachii
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What passes into each posterior shoulder space?
What passes into each posterior shoulder space?
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Axillary Artery Parts
Axillary Artery Parts
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Study Notes
Axilla and Brachial Plexus
- The axilla is a gateway to the upper limb.
- The axilla is an irregular pyramid with four sides, an inlet, and a floor.
- The axilla contains nerves, arteries, veins, and parts of the biceps brachii and coracobrachialis.
- The brachial plexus is formed by the anterior rami of C5-C8 and T1.
- The brachial plexus roots pass between anterior and middle scalene muscles.
- The brachial plexus then forms three trunks.
- The trunks then form six divisions.
- The divisions then form three cords.
- The cords are named by their position (lateral, medial, posterior).
- The cords create five terminal branches (nerves).
Learning Outcomes
- Describe the structure and function of the muscles of the pectoral girdle and back.
- Identify the axilla and its contents (e.g., artery, vein).
- Discuss the structure and function of the brachial plexus and its branches.
- Demonstrate clinically relevant anatomical landmarks.
- Identify the structure and function of the breast and underlying muscles/fascia.
- Describe breast changes due to gender, age, or disease.
- Discuss the vascular and lymphatic components of the breast and their relation to aging and disease.
Breast
- Mammary glands are modified sweat glands.
- Subcutaneous fat gives breasts their contour and volume, except during pregnancy.
- The circular base of the female breast extends transversely from the sternum to the anterior axillary line and vertically from the second to sixth ribs.
- A small part extends to the inferolateral edge of the pectoralis major muscle.
- The retro-mammary space (bursa) is between the breast and the deep pectoral fascia.
- The breast contains 15-20 lobules of glandular tissue, each drained by a lactiferous duct that opens on the nipple.
- Each duct has a dilated portion, the lactiferous sinus.
- Suspensory ligaments connect the mammary glands to the dermis.
- The areola is a circular pigmented area.
- The nipple is a prominence of the breast.
Axilla-Content
- Proximal parts of biceps brachii and coracobrachialis pass through the axilla.
- The axillary artery and vein pass through.
- The brachial plexus passes through.
- Five groups of lymph nodes are found within the axilla (anterior, posterior, lateral, central, apical).
Axillary Artery
- Continuation of subclavian.
- Separated into three parts by pectoralis minor.
- The three parts include: superior thoracic, thoraco-acromial, lateral thoracic, subscapular, anterior circumflex, and posterior circumflex.
Brachial Plexus
- The brachial plexus is formed by anterior rami of C5-T1 spinal nerves.
- Roots pass into the posterior triangle, pass lateral to rib one.
- Three trunks (upper, middle, lower) are formed.
- Trunks branch into six divisions.
- Divisions form three cords (lateral, medial, posterior).
- Three cords branch into five terminal branches (nerves).
Roots of Brachial Plexus
- Originate from spinal nerves (C5-T1).
- Dorsal scapular nerve (C5): innervates rhomboid major and minor.
- Long thoracic nerve (C5,6,7): innervates serratus anterior muscle.
- C5 contributes to the phrenic nerve, innervating the diaphragm.
Nerves of Brachial Plexus (Cords)
- Lateral Cord - Lateral pectoral nerve (pectoralis major), lateral root of median nerve, and a cutaneous nerve.
- Medial Cord - Medial pectoral nerve (pectoralis major and minor), medial cutaneous nerve of the arm and forearm, medial root of median nerve, and ulnar nerve (for one and half anterior muscles in forearm and hand sensory to medial one and a half hand).
- Posterior Cord - Superior/upper subscapular nerve(subscapularis), inferior/lower subscapular nerve (subscapularis and teres major), thoracodorsal nerve(latissimus dorsi), and axillary nerve (deltoid and teres minor), radial nerve (posterior compartment of arm and forearm, cutaneous to posterior arm, forearm and dorsal lateral hand).
Cutaneous Innervation
- Branches of nerves innervate different areas of the upper limb (brachial, antebrachial, and costal).
Injuries to the Brachial Plexus
- Injuries affect muscle movements (paralysis) and cutaneous sensations (anesthesia).
Erb-Duchenne Palsy
- Injury to superior parts of the brachial plexus (C5, C6, sometimes C7).
- Results in waiter's tip position (adducted and internally rotated arm, extended elbow, pronated forearm and flexed wrist).
- Diminished sensation from lateral aspect of upper limb.
Klumpke Palsy
- Injury to inferior parts of brachial plexus (C8, T1).
- Results in hand paralysis (affects muscles of forearm and hand supplied by C8, T1 fibers).
- Symptoms include claw hand and wasting of hand intrinsic muscles, supinated forearm and diminished sensation in medial arm and forearm.
Superficial Muscles
- Trapezius - Originates from spinous processes of C7-T12 and ligamentum nuchae, inserting into scapular spine, acromion and clavicle. Elevates, retracts, depresses, and rotates scapula. Innervated by accessory nerve.
- Deltoid - Originates from scapular spine, acromion, and clavicle and inserts to deltoid tuberosity. Abducts arm beyond 15°, flexes, and extends arm. Innervated by axillary nerves.
- Rotator Cuff Muscles - Supraspinatus, Infraspinatus, Teres Minor, and Subscapularis: stabilize shoulder joint. Supraspinatus assists in arm abduction (15°). Infraspinatus and Teres Minor are lateral rotators. Subscapularis is medial rotator.
Gateways in the Posterior Wall
- Suprascapular Foramen: Suprascapular nerve and artery.
- Quadrangular Space: Axillary nerve and posterior circumflex humeral artery.
- Triangular Space: Circumflex scapular artery.
- Triangular Interval: Radial nerve and profunda brachii artery.
Axilla-Content (Review)
- Proximal parts of biceps brachii and coracobrachialis.
- Axillary artery and vein.
- Brachial plexus.
- Lymphatics (five groups: anterior/pectoral, posterior/subscapular, lateral/humeral, central, and apical).
Important Muscles and Nerves
- Important muscles and nerves relevant to upper limb motor and sensory innervation and function.
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Description
This quiz covers the anatomy of the axilla and brachial plexus. You will learn about the structure and function of the components found within the axilla, including nerves, arteries, and muscles. Additionally, the quiz will delve into the formation and branches of the brachial plexus and its clinical significance.
