What muscle is affected in paralysis of the Serratus Anterior?
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Serratus Anterior muscle.
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What muscle is affected in paralysis of the Serratus Anterior?
Serratus Anterior muscle.
What is the origin of the axillary nerve?
It originates from the posterior cord of the brachial plexus.
Where are intermuscular spaces primarily located?
Around the scapular region.
What is the primary action of the levator scapulae?
Raises the medial border of the scapula.
What is the origin of the Teres Minor muscle?
Upper two thirds of the lateral border of the scapula.
Where does the Supraspinatus muscle insert?
Greater tuberosity of humerus; capsule of shoulder joint.
How are the superficial muscles of the back arranged?
In two layers.
Which muscle is located beneath the pectoralis major?
Pectoralis minor.
What is the primary action of the Teres Minor muscle?
Laterally rotates the arm and stabilizes the shoulder joint.
What are the supraclavicular nerves responsible for?
They supply the skin over the upper half of the deltoid and from the clavicle down to the second rib.
What is the origin of the Supraspinatus muscle?
Supraspinous fossa of scapula.
What forms the lateral boundary of the quadrangular space?
The surgical neck of the humerus.
What is the origin of the Infraspinatus muscle?
Infraspinous fossa of scapula.
What is the nerve supply for the Rhomboid Minor?
Dorsal scapular nerve (C4,5).
Where does the Subclavius muscle insert?
Subclavian groove.
Where does the Teres Major muscle insert?
Medial lip of the bicipital groove of the humerus.
What forms the inferior boundary of the Upper Triangular space?
The superior margin of teres major.
What forms the inferior boundary of the quadrangular space?
The superior margin of teres major.
What is the primary action of the Supraspinatus muscle?
Abducts arm and stabilizes shoulder joint.
What is the significance of the surgical neck of the humerus?
It is a common site for fractures that can affect the axillary nerve.
What is the role of the subclavius muscle?
It helps stabilize the clavicle.
From where does the Posterior Circumflex Humeral Artery originate?
From the third part of the axillary artery in the axilla.
What is a key symptom of Serratus Anterior paralysis?
Winged scapula.
What forms the superior boundary of the quadrangular space?
The inferior margin of teres minor.
What is the location of the Lower Triangular Space?
Below the inferior margin of teres major.
What forms the medial boundary of the Lower Triangular Space?
The lateral margin of the long head of triceps brachii.
Where does the Infraspinatus muscle insert?
Greater tuberosity of humerus; capsule of shoulder joint.
Where does the Rhomboid Major insert?
Medial border of scapula from root of the spine to the inferior angle.
What is the nerve supply for the Rhomboid Major?
Dorsal scapular nerve (C4,5).
What does the intercostobrachial nerve (T2) supply?
It supplies the skin of the floor of the axilla and the upper half of the medial side of the arm.
What is the role of the Serratus Anterior muscle?
It stabilizes the scapula against the thoracic wall.
From which view is the musculotendinous cuff observed in this context?
Right anterolateral view.
What are the muscles of the pectoral region also known as?
Anterior Axio-appendicular Muscles or Thoraco-appendicular muscles.
What anatomical structure is associated with the axillary nerve?
The deltoid muscle.
What forms the lateral boundary of the Lower Triangular Space?
The shaft of the humerus.
What is the function of the trapezius muscle?
It helps in moving, rotating, and stabilizing the shoulder blade.
What is the role of the latissimus dorsi muscle?
It is involved in the extension, adduction, and internal rotation of the shoulder.
Where does the Pectoralis Minor Muscle insert?
Medial border and superior surface of the coracoid process of the scapula.
Which nerve supplies the Supraspinatus muscle?
Suprascapular nerve (C4, 5, 6).
Name one muscle found in the pectoral region.
Pectoralis major.
What is the origin of the levator scapulae?
Transverse processes of the first four cervical vertebrae.
What actions does the Teres Major muscle perform?
Medially rotates and adducts the arm, and stabilizes the shoulder joint.
What is the primary action of the Infraspinatus muscle?
Laterally rotates arm and stabilizes shoulder joint.
What are the four muscles that make up the Rotator Cuff?
Supraspinatus, Infraspinatus, Teres Minor, Subscapularis.
What does the Posterior Circumflex Humeral Artery supply?
Related muscles and the glenohumeral joint.
What is one of the intermuscular spaces in the scapular region?
The quadrangular space.
What is Poland anomaly?
A congenital condition characterized by the absence or underdevelopment of the pectoral muscles on one side of the body.
Through which foramen does the suprascapular nerve pass to reach the posterior scapular region?
The suprascapular foramen.
Where does the Pectoralis Major Muscle insert?
Lateral lip of the intertubercular groove.
What is the nerve supply for the trapezius muscle?
Spinal part of accessory nerve (motor) and C3 and C4 (sensory).
What is the origin of the Serratus Anterior muscle?
Lateral surfaces of upper 8-9 ribs and deep fascia overlying the related intercostal spaces.
What does the Serratus Anterior muscle help maintain?
Keeps the medial border and inferior angle of the scapula opposed to the thoracic wall.
Name three muscles that are components of the rotator cuff.
Supraspinatus, infraspinatus, and teres minor.
Which muscle is NOT part of the rotator cuff but is found in the scapular region?
Teres major.
What forms the superior boundary of the Upper Triangular space?
The inferior margin of teres minor.
What is the primary function of the muscles in the pectoral region?
To move the pectoral girdle.
What muscles are included in the outer layer of the superficial back muscles?
Trapezius and Latissimus dorsi.
What is the nerve supply for the Teres Major muscle?
Lower subscapular nerve (C6,7).
What action does the Rhomboid Minor perform?
Raises medial border of scapula upward and medially.
Through which space does the Posterior Circumflex Humeral Artery leave the axilla?
The quadrangular space.
How does Serratus Anterior paralysis affect shoulder movement?
It impairs the ability to raise the arm above the head.
Which muscles are typically included in the musculotendinous cuff?
Supraspinatus, Infraspinatus, Teres Minor, and Subscapularis.
Where does the Circumflex Scapular Artery enter after leaving the axilla?
The posterior scapular region.
What type of imaging is used to visualize the normal glenohumeral joint?
Magnetic resonance imaging (MRI).
What is the origin of the Pectoralis Major Muscle?
Medial 2/3 of the anterior surface of the clavicle, anterior surface of the sternum, first seven costal cartilages, and aponeurosis of the external oblique.
Does the suprascapular nerve have cutaneous branches?
No, it has no cutaneous branches.
Where does the Subscapularis muscle insert?
Lesser tuberosity of the humerus.
What are the scapulo-humeral muscles also known as?
Intrinsic shoulder muscles.
Which muscle is responsible for initiating shoulder abduction?
Supraspinatus muscle.
What is the function of the teres major muscle?
It assists in shoulder adduction and internal rotation.
What does the Posterior Superficial View show?
It displays the superficial structures located at the back of the body.
Where is the axillary nerve located in relation to the deltoid region?
In the horizontal section at the level of the surgical neck of the humerus.
Where does the Teres Minor muscle insert?
Greater tuberosity of the humerus; capsule of the shoulder joint.
What is the origin of the Rhomboid Major?
Second to fifth thoracic spines.
Which muscle is responsible for protracting the scapula?
Serratus anterior.
What innervates the Subclavius muscle?
Nerve to subclavius.
What region does the Posterior Circumflex Humeral Artery enter after leaving the axilla?
The posterior scapular region.
How many intermuscular spaces are identified in the scapular region?
Three.
What is the origin of the suprascapular nerve?
It originates from the superior trunk of the brachial plexus.
What muscle's origin does the Circumflex Scapular Artery pass through?
The teres minor muscle.
What type of connections does the Circumflex Scapular Artery form?
Anastomotic connections with other arteries in the region.
What happens with an injury to the Thoracodorsal Nerve?
Weakness in the latissimus dorsi muscle, affecting arm adduction and extension.
What action do the upper fibers of the trapezius perform?
Elevate the scapula.
Where does the Serratus Anterior muscle insert?
Costal surface of the medial border of the scapula.
What area does the scapular region occupy?
The posterior aspect of the scapula.
What is the primary bone that forms the shoulder blade?
The scapula.
What is depicted in the Posterior Deep View?
It reveals the deeper structures located at the back of the body.
What forms the superior boundary of the Lower Triangular Space?
The inferior margin of teres major.
Where does the Rhomboid Minor insert?
Medial border of scapula opposite to the root of the spine.
What is the origin of the Subclavius muscle?
First rib at the junction between rib and costal cartilage.
What is a common cause of Serratus Anterior paralysis?
Damage to the long thoracic nerve.
Which nerves supply the skin below the level of the second rib?
The anterior and lateral cutaneous branches of the 2nd to 6th intercostal nerves.
What forms the intermuscular spaces in the scapular region?
The long head of triceps, other muscles, and the humerus.
What artery leaves the axilla through the triangular space?
Circumflex Scapular Artery.
What is the suprascapular artery a branch of?
The thyrocervical trunk.
What actions does the Latissimus Dorsi perform?
Extension, adduction, and medial rotation of the arm.
What forms the inferolateral border of the Triangle of Auscultation?
The trapezius.
Which nerves innervate the Pectoralis Major Muscle?
Medial and lateral pectoral nerves.
What joint is being imaged in the MRI?
Glenohumeral joint.
What nerves supply the Subscapularis muscle?
Upper and lower subscapular nerves (C5, 6, 7).
What is the primary function of scapulo-humeral muscles?
To act on the glenohumeral joint.
What is the function of the rotator cuff?
To stabilize the glenohumeral joint.
What is the long head of triceps associated with?
It is one of the muscles in the scapular region.
What forms the medial boundary of the quadrangular space?
The lateral margin of the long head of triceps brachii.
What is the origin of the Rhomboid Minor?
Ligamentum nuchae and spines of 7th cervical and 1st thoracic vertebrae.
Which nerve supplies the Teres Minor muscle?
Axillary nerve (C4, C5,6).
Where does the levator scapulae insert?
Medial border of the scapula from the superior angle to the root of the spine.
What is the origin of the Pectoralis Minor Muscle?
Anterior surfaces of the third, fourth, and fifth ribs near costal cartilages, and deep fascia overlying the related intercostal spaces.
What action does the Rhomboid Major perform?
Raises medial border of scapula upward and medially.
What is the origin of the Latissimus Dorsi?
Iliac crest, thoracolumbar fascia, spines of lower six thoracic vertebrae, lower three or four ribs, and inferior angle of scapula.
Where does the Latissimus Dorsi insert?
Floor of bicipital groove of humerus.
Name another intermuscular space besides the quadrangular space.
The upper triangular space.
What is a common consequence of paralysis of the Serratus Anterior muscle?
Winged scapula, which affects shoulder movement.
How do veins in the posterior scapular region behave?
They generally follow the arteries.
What are the effects of an injury to the Dorsal Scapular Nerve?
Weakness in the rhomboid muscles, leading to difficulty in scapular retraction.
Which nerve supplies the Deltoid muscle?
Axillary nerve (C5,6).
What forms the lateral boundary of the Upper Triangular space?
The medial margin of the long head of triceps brachii.
What is the origin of the Teres Major muscle?
Lower third of the lateral border of the scapula.
Which muscles make up the inner layer of the superficial back muscles?
Levator scapulae, rhomboideus minor, and rhomboideus major.
Which nerve supplies the Infraspinatus muscle?
Suprascapular nerve (C4, 5, 6).
What nerves supply the levator scapulae?
C3 and C4 and the dorsal scapular nerve (C3, 4, 5).
What is one of the main actions of the Subclavius muscle?
Pulls clavicle medially to stabilize the sternoclavicular joint.
What is the name of the cutaneous branch of the axillary nerve?
The superior lateral cutaneous nerve of the arm.
Where is the Triangle of Auscultation located?
Near the inferior angle of the scapula.
How does the suprascapular nerve travel from its origin?
It passes postero-laterally from its origin.
What is the origin of the trapezius muscle?
External occipital protuberance, medial 2/3 of the superior nuchal line, ligamentum nuchae, spine of 7th cervical vertebra, spines of all thoracic vertebrae.
What is the orientation of the MRI for the glenohumeral joint described?
Sagittal plane.
What are the primary actions of the Pectoralis Major Muscle?
Adduction, medial rotation, and flexion of the humerus at the shoulder joint.
What is the origin of the Subscapularis muscle?
Subscapular fossa.
How does the axillary nerve leave the axilla?
By passing through the quadrangular space in the posterior wall of the axilla.
Which muscles does the axillary nerve innervate?
The deltoid and teres minor muscles.
What is the Triangle of Auscultation?
A small triangular gap in the musculature on the back of the thorax.
What is another name for the Rotator Cuff Muscles?
SITS Muscles.
With which nerve does the suprascapular artery run in the posterior scapular region?
The suprascapular nerve.
Where do the middle and lower fibers of the trapezius insert?
Into the acromion and spine of the scapula.
What is a potential consequence of a fracture–dislocation of the proximal humeral epiphysis?
Damage to surrounding nerves and blood vessels, leading to complications in shoulder function.
What actions do the anterior fibers of the Deltoid perform?
Flex and medially rotate the arm.
Which muscles are located deep to the trapezius and deltoid muscles?
The muscles of the scapular region.
Which muscle is primarily responsible for internal rotation of the shoulder?
Subscapularis muscle.
What is the primary function of the musculotendinous cuff?
To stabilize the shoulder joint.
What are the actions of the Pectoralis Minor Muscle?
Depresses the tip of the shoulder; protracts the scapula; stabilizes the scapula by drawing it inferiorly and anteriorly against the thoracic wall.
What role do the Rotator Cuff Muscles play in joint stability?
They reinforce the fibrous layer of the joint capsule of the glenohumeral joint, protecting and stabilizing it.
Where does the suprascapular artery enter the posterior scapular region?
Superior to the suprascapular foramen.
How does the Latissimus Dorsi assist during climbing?
It raises the body toward the arms.
With which areas do the veins in the posterior scapular region connect?
Neck, back, arm, and axilla.
What action do the middle fibers of the trapezius perform?
Pull the scapula medially.
Which nerve innervates the Serratus Anterior muscle?
Long thoracic nerve [C5, C6, C7].
Which muscles connect the scapula to the humerus?
Scapulo-humeral muscles.
What muscles are associated with the superficial back and scapular region?
Trapezius, latissimus dorsi, and deltoid.
Which nerves innervate the Pectoralis Minor Muscle?
Medial pectoral nerves.
How do the Rotator Cuff Muscles interact with the shoulder joint?
They blend with the fibrous capsule of the shoulder joint.
What is the nerve supply for the Latissimus Dorsi?
Thoracodorsal nerve (C6, 7, 8).
What forms the medial border of the Triangle of Auscultation?
The scapula.
What is the result of an injury to the Spinal Accessory Nerve (CN XI)?
Weakness in shoulder elevation and head rotation.
What is the origin of the Deltoid muscle?
Anterior border of lateral one third of the clavicle, acromion, spine of scapula.
What actions do the posterior fibers of the Deltoid perform?
Extend and laterally rotate the arm.
What are the main features of the scapula?
The spine, acromion, coracoid process, and glenoid cavity.
What is the function of the acromion process?
It serves as an attachment point for muscles and ligaments.
What is the primary function of the Rotator Cuff Muscles?
To form a musculotendinous rotator cuff around the glenohumeral joint.
What are the three major arteries of the scapular region?
Suprascapular artery, posterior circumflex humeral artery, circumflex scapular artery.
What forms the superior horizontal border of the Triangle of Auscultation?
The latissimus dorsi.
What is the significance of the infraspinatus muscle?
It is responsible for external rotation of the shoulder.
Which muscles does the suprascapular nerve innervate?
The supraspinatus and infraspinatus muscles.
What specific MRI sequence is mentioned for the glenohumeral joint?
T1-weighted.
What action do the lower fibers of the trapezius perform?
Pull the medial border of the scapula downward.
What is the primary action of the Serratus Anterior muscle?
Protraction and rotation of the scapula.
How many muscles are contained in the scapular region?
Five muscles.
Name one of the scapulo-humeral muscles.
Deltoid muscle.
Which muscle is involved in external rotation of the shoulder?
Infraspinatus muscle.
Which muscle is responsible for external rotation and stabilization of the shoulder?
Teres minor muscle.
What is another action of the Subclavius muscle?
Anchors and depresses the clavicle.
What sensation does the superior lateral cutaneous nerve of the arm carry?
General sensation from the skin over the inferior part of the deltoid muscle.
What role does the supraspinatus play in the musculotendinous cuff?
It initiates arm abduction.
What is the third intermuscular space in the scapular region?
The lower triangular space.
Where do the upper fibers of the trapezius insert?
Into the posterior border of the lateral third of the clavicle.
What lies deep to the Triangle of Auscultation?
The upper part of the lower lobe of the lung.
Where does the Deltoid muscle insert?
Middle of lateral surface of shaft of humerus (Deltoid tuberosity).
What is the primary action of the Subscapularis muscle?
Medially rotates the arm and stabilizes the shoulder joint.
What type of muscles are the scapulo-humeral muscles?
Relatively short muscles.
What structures form the floor of the Triangle of Auscultation?
The 6th and 7th ribs and the 6th intercostal space.
What is regimental badge anesthesia associated with?
Injury to the Axillary Nerve, leading to sensory loss over the lateral shoulder.
What is the primary action of the Deltoid muscle?
Abducts the arm.
Where is the scapula located in relation to the rib cage?
It is located on the posterior side of the rib cage.
What is the significance of the glenoid cavity?
It articulates with the head of the humerus to form the shoulder joint.
What is the role of the scapula in shoulder movement?
It provides a stable base for shoulder joint movement.
