Upper Body Muscles COPY COPY Flashcards
Temporalis
Attachment:
Temporal Fossa to Coronoid Process of Mandible.
Function:
Elevates and retracts the mandible (closes the jaw).
Nerve Supply:
Mandibular branch of the Trigeminal (V) nerve.
Masseter
Attachment:
Zygomatic Arch to Ramus of Mandible (angle of mandible).
Function:
Elevates and closes the jaw.
Nerve Supply:
Mandibular branch of the Trigeminal (V) nerve.
Lateral Pterygoid
Attachment:
Sphenoid Bone to Temporomandibular Joint (TMJ) Joint.
Function:
Protracts the mandible, assists in jaw opening, and aids in side-to-side movements of the jaw.
Nerve Supply: Mandibular branch of the Trigeminal (V) nerve.
Medial Pterygoid
Attachment: Maxilla to Lateral Pterygoid Plate (Sphenoid Bone).
Function: Elevates the mandible, assists in jaw closure, and aids in side-to-side movements of the jaw.
Nerve Supply: Mandibular branch of the Trigeminal (V) nerve.
Diaphragm Muscle:
Attachment:
Attaches to the xiphoid process of the sternum, lower ribs, and lumbar vertebrae (L1-L3).
Function:
The primary muscle of respiration; is when it contracts, it flattens and increases the volume of the thoracic cavity, causing inhalation. When it relaxes, it returns to its dome shape and causes exhalation.
Nerve Supply:
Phrenic nerves (C3-C5)
Blood Supply;
Phrenic Arteries
External Intercostal Muscles:
Attachment:
Located between adjacent ribs.
Function:
Elevate ribcage during inhalation, expanding the thoracic cavity to assist in breathing.
Nerve Supply:
Intercostal nerves
Blood Supply:
Intercostal arteries,
Internal Intercostal Muscles:
Attachment:
Also situated between adjacent ribs.
Function:
Aid in the forced expiration by depressing the ribcage, reducing the thoracic cavity’s volume.
Nerve Supply:
Intercostal nerves.
Blood Supply:
Intercostal arteries, which originate from the thoracic aorta.
Innermost Intercostal Muscles:
Attachment:
deep within the intercostal spaces, between adjacent ribs.
Function:
Aid in the forced expiration by depressing the ribcage, reducing the thoracic cavity’s volume,
Nerve Supply:
Intercostal nerves
Blood Supply:
Intercostal arteries
Serratus Posterior Superior:
Attachment:
Attaches to the lower cervical and upper thoracic vertebrae to the upper ribs (2nd to 5th).
Function:
Elevates the upper ribs, assisting in inhalation.
Nerve Supply:
Intercostal nerves (upper five intercostal nerves)
Blood Supply:
intercostal arteries.
Serratus Posterior Inferior:
Attachment:
Originates from the lower thoracic and upper lumbar vertebrae to the lower ribs (8th to 12th).
Function:
Depresses the lower ribs, aiding in forced exhalation.
Nerve Supply:
Intercostal nerves (lower five intercostal nerves).
Blood Supply:
posterior intercostal arteries.
Rectus Abdominis
Attachment: (dktk)
Originates from the pubic symphysis and inserts into the costal cartilages of the 5th to 7th ribs and the xiphoid process.
Function:
Flexes the vertebral column and compresses the abdominal contents.
Nerve Supply:
Thoracioabdominal nerves, Lower six intercostal nerves (T7-T11) and subcostal nerves (T12).
Blood Supply:
Subclavian Artery -> Internal Thoracic artery
Supplied by the superior epigastric artery, inferior epigastric artery, and the musculophrenic artery
Internal Obliques
Layer 2
Attachment: (dntk)
Originates from the iliac crest, and inguinal ligament, inserting into the lower three ribs,
Function:
Contributes to trunk flexion, rotation, and lateral flexion while also compressing the abdominal contents.
Nerve Supply:
Lower six intercostal nerves (T7-T11) and the subcostal nerve (T12).
Blood Supply:
Originate at Thoracic Aorta
External Obliques
Layer 1
Attachment:
Originates from the lower eight ribs, inserting into the iliac crest, inguinal ligament, and linea alba.
Function:
Primarily responsible for trunk flexion, rotation, and lateral flexion while also assisting in compressing the abdominal contents.
Nerve Supply:
Lower six intercostal nerves (T7-T11) and the subcostal nerve (T12).
Blood Supply:
Originates at Thoracic Aorta
Supplied by the superior epigastric artery, inferior epigastric artery, and the musculophrenic artery
Pyramidalis
Attachment:
Attaches to the pubic symphysis and the linea alba.
Function:
Assists in tensioning the linea alba and flexing the anterior abdominal wall.
Nerve Supply:
The lower six intercostal nerves (T7-T11) and the subcostal nerve (T12)
Blood Supply:
Iliac Artery
Supplied by branches of the lower epigastric arteries and other vessels in the abdominal region.
Transversus Abdominis
Layer 3
Attachment:
Originates from the lower six ribs, iliac crest, and inguinal ligament, and inserts into the linea alba and the pubic crest.
Function:
Acts as the innermost layer of the abdominal muscles, providing stability to the abdominal wall and assisting in compression of the abdominal contents.
Nerve Supply:
Lower six intercostal nerves (T7-T11) and the subcostal nerve (T12)
Blood Supply:
Thoracic and Iliac Artery
Splenius Capitis:
Attachment:
Originates from the nuchal ligament and spinous processes of the vertebrae C7-T6, inserting into the mastoid process of the temporal bone and the occipital bone.
Function:
Extends, rotates, and laterally flexes the head and neck.
Nerve Supply:
posterior rami of the cervical spinal nerves.
Blood Supply:
occipital artery and the vertebral artery.
Splenius Cervicis:
Attachment:
Originates from the spinous processes of T3-T6 or T3-T7 and inserts into the transverse processes of C1-C3 or C4.
Function:
Extends, rotates, and laterally flexes the cervical spine.
Nerve Supply:
posterior rami of the cervical spinal nerves.
Blood Supply:
vertebral artery and deep cervical artery.
Longissimus Thoracis:
Attachment:
Originates from the transverse processes of thoracic vertebrae and inserts into the transverse processes of lumbar vertebrae.
Function:
Extends and laterally flexes the spine and supports posture.
Nerve Supply:
posterior rami of the spinal nerves.
Blood Supply:
posterior intercostal arteries and lumbar arteries.
Iliocostalis Thoracis:
Attachment:
Originates from the iliac crest and inserts into the ribs.
Function:
Extends and laterally flexes the spine and helps with posture.
Nerve Supply:
posterior rami of the spinal nerves.
Blood Supply:
intercostal arteries and lumbar arteries.
Spinalis Thoracis:
Attachment:
Originates from the spinous processes of the lower thoracic and upper lumbar vertebrae, and inserts into the spinous processes of the upper thoracic vertebrae.
Function:
Extends the thoracic spine and supports posture.
Nerve Supply:
Innervated by posterior rami of spinal nerves.
Blood Supply:
posterior intercostal arteries and lumbar arteries.
Semispinalis Capitis
and
Semispinalis Thoracis
Attachment:
Originates from the transverse processes of the thoracic and cervical vertebrae and inserts into the spinous processes of upper thoracic and cervical vertebrae.
Function:
Extends and rotates the spine and supports posture.
Nerve Supply:
Innervated by posterior rami of spinal nerves.
Blood Supply:
posterior intercostal arteries and lumbar arteries.
Multifidus
Attachment:
Originates from the sacrum, posterior superior iliac spine, and the transverse processes of lumbar and thoracic vertebrae, inserting into the spinous processes of the vertebrae.
Function:
Stabilizes and extends the spine, supporting posture and fine movements of the vertebral column.
Nerve Supply:
Innervated by posterior rami of spinal nerves.
Blood Supply:
posterior intercostal arteries and lumbar arteries.
Rotatores
Attachment:
Originates from the transverse processes of the vertebrae and inserts into the spinous processes of the vertebrae above.
Function:
Assist in rotation and lateral flexion of spine.
Nerve Supply:
Innervated by posterior rami of spinal nerves.
Blood Supply:
posterior intercostal arteries and lumbar arteries.
Obliquus Capitis Superior:
NEED TO KNOW SPECIFIC ATTACHMENT
Attachment:
Originates from the transverse process of the atlas (C1) and inserts into the occipital bone.
Function:
Primarily responsible for lateral flexion and rotation of the head and neck.
Nerve Supply:
Innervated by the suboccipital nerve (C1)
Blood Supply:
vertebral artery and occipital artery.
Obliquus Capitis Inferior:
NEED TO KNOW SPECIFIC ATTACHMENT
Attachment:
Originates from the spinous process of the axis (C2) and inserts into the transverse process of the atlas (C1).
Function:
Primarily responsible for the rotation of the head and neck.
Nerve Supply:
Innervated by the suboccipital nerve (C1),
Blood Supply:
vertebral artery and occipital artery.
Rectus Capitis Posterior Minor:
NEED TO KNOW SPECIFIC ATTACHMENT
Attachment:
Originates from the posterior tubercle of the atlas (C1) and inserts into the inferior nuchal line of the occipital bone.
Function:
head extension and minor lateral flexion.
Nerve Supply:
Innervated by the suboccipital nerve (C1)
Blood Supply:
vertebral artery and occipital artery
Rectus Capitis Posterior Major:
NEED TO KNOW SPECIFIC ATTACHMENT
Attachment:
Originates from the spinous process of the axis (C2) and inserts into the inferior nuchal line of the occipital bone.
Function:
Primarily responsible for head extension.
Nerve Supply:
Innervated by the suboccipital nerve (C1)
Blood Supply:
vertebral artery and occipital artery.
Pectoralis Major:
Attachment:
Originates from the clavicle, sternum, and upper six costal cartilages, inserting into the greater tubercle of the humerus.
Function:
including arm flexion, adduction, and medial rotation.
Nerve Supply:
medial and lateral pectoral nerves.
Blood Supply:
axillary artery and thoracoacromial artery
Pectoralis Minor:
Attachment:
Originates from the anterior surfaces of the third, fourth, and fifth ribs, and inserts into the coracoid process of the scapula.
Function:
Stabilizes the scapula, scapular protraction and depression.
Nerve Supply:
Innervated by the medial pectoral nerve.
Blood Supply:
axillary artery and thoracoacromial artery.
Subclavius Muscle:
Attachment:
Originates from the first rib and its cartilage, and inserts into the inferior surface of the clavicle.
Function:
stabilizes and depresses the clavicle
Nerve Supply:
Innervated by the subclavian nerve.
Blood Supply:
Axillary artery & thoracoacromial artery.
Clavicular Head of Deltoid:
(Anterior/Frontal)
Attachment:
Originates from the lateral third of the clavicle.
attaches to deltoid tuberosity
Function:
Assists in arm flexion and medial rotation.
Nerve Supply:
Innervated by the axillary nerve (C5-C6).
Blood Supply:
Axillary artery
Acromial Head of Deltoid:
(Medial)
Attachment:
Originates from the acromion process of the scapula.
Inserts into deltoid tubersoity
Function:
Primarily responsible for arm abduction.
Nerve Supply:
Innervated by the axillary nerve (C5-C6).
Blood Supply:
axillary artery
Spinal Head of Deltoid:
(Posterior/Rear)
Attachment:
Originates from the spine of the scapula.
Attaches to the Deltoid tuberosity
Function:
Assists in arm extension and lateral rotation.
Nerve Supply:
Innervated by the axillary nerve (C5-C6).
Blood Supply:
Receives blood from branches of the anterior and posterior circumflex humeral arteries.
Serratus Anterior:
Attachment:
Originates from the lateral surface of the first to ninth ribs and inserts into the anterior surface of the medial border of the scapula.
Function:
The serratus anterior muscle is responsible for scapular protraction, upward rotation, and assists in maintaining scapular stability, allowing for smooth arm movements.
Nerve Supply:
Innervated by the long thoracic nerve (C5-C7).
Blood Supply:
lateral thoracic artery.
Levator Scapulae:
Attachment:
Originates from the transverse processes of the cervical vertebrae (C1-C4) and inserts into the medial border of the scapula.
Function: Elevates and retracts the scapula.
Nerve Supply: Innervated by the dorsal scapular nerve (C3-C4) and the third and fourth cervical nerves (C3-C4).
Blood Supply:
dorsal scapular artery and ascending cervical artery.
Rhomboid Major:
Attachment:
Originates from the spinous processes of the thoracic vertebrae (T2-T5) and inserts into the medial border of the scapula.
Function:
Retracts and stabilizes the scapula.
Nerve Supply:
Innervated by the dorsal scapular nerve (C5).
Blood Supply:
dorsal scapular artery.
Rhomboid Minor:
Attachment:
Originates from the spinous processes of the upper thoracic vertebrae (C7-T1) and inserts into the medial border of the scapula.
Function:
Retracts and stabilizes the scapula.
Nerve Supply:
Innervated by the dorsal scapular nerve (C5).
Blood Supply:
dorsal scapular artery.
Trapezius:
has a superior, middle and inferior part
Attachment:
Originates from the nuchal ligament, spinous processes of the cervical and thoracic vertebrae (C7-T12), and the scapular spine, inserting into the clavicle and acromion process of the scapula.
Function:
The trapezius muscle is responsible for various movements of the scapula and supports head and neck movement.
Nerve Supply:
Innervated by the accessory nerve (cranial nerve XI) and branches of the cervical spinal nerves (C3-C4).
Blood Supply:
transverse cervical artery and superficial cervical artery.
Latissimus Dorsi:
Attachment:
Originates from the spinous processes of the lower thoracic and lumbar vertebrae, iliac crest, and lower three or four ribs, and inserts into the humerus (intertubercular groove).
Function:
The latissimus dorsi muscle primarily facilitates arm extension, adduction, and medial rotation.
Nerve Supply:
Innervated by thoracodorsal nerve (C6-C8).
Blood Supply:
thoracodorsal artery.
Teres Major:
Attachment:
Originates from the inferior angle of the scapula and inserts into the humerus (intertubercular groove).
Function:
Assists in arm adduction and medial rotation.
Nerve Supply:
lower subscapular nerve (C5-C7).
Blood Supply:
subscapular artery
Teres Minor:
Attachment:
Originates from the lateral border of the scapula and inserts into the greater tubercle of the humerus.
Function:
lateral rotation of the arm.
Nerve Supply:
Innervated by the axillary nerve (C5-C6).
Blood Supply:
circumflex scapular artery
Supraspinatus:
Attachment:
Originates from the supraspinous fossa of the scapula and inserts into the greater tubercle of the humerus.
Function:
arm abduction, specifically during the first 15 degrees of this movement.
Nerve Supply:
Innervated by suprascapular nerve (C5-C6).
Blood Supply:
suprascapular artery
Subscapularis
Attachment:
Originates from the subscapular fossa of the scapula and inserts into the lesser tubercle of the humerus.
Function:
The subscapularis muscle is the most powerful medial rotator of the arm and contributes to shoulder joint stability.
Nerve Supply:
Innervated by the upper and lower subscapular nerves (C5-C6).
Blood Supply:
Receives blood from branches of the subscapular artery.
Infraspinatus
Attachment:
Originates from the infraspinous fossa of the scapula and inserts into the greater tubercle of the humerus.
Function:
The infraspinatus muscle is primarily responsible for lateral (external) rotation of the arm, contributing to shoulder joint stability.
Nerve Supply:
Innervated by suprascapular nerve (C5-C6).
Blood Supply:
suprascapular artery
Biceps Brachii:
Attachment:
Originates from the scapula (long head) and the coracoid process of the scapula (short head) and inserts into the radial tuberosity and the forearm fascia.
Function:
elbow flexion, forearm supination, and assists in shoulder flexion.
Nerve Supply:
musculocutaneous nerve (C5-C6).
Blood Supply:
Supplied by branches of the brachial artery.
Brachialis:
Attachment:
Originates from the distal half of the anterior surface of the humerus and inserts into the ulnar tuberosity.
Function:
primary flexor of the elbow joint.
Nerve Supply:
musculocutaneous nerve (C5-C6) and the radial nerve.
Blood Supply:
brachial artery.
Coracobrachialis
Attachment:
Originates from the coracoid process of the scapula and inserts into the medial surface of the humerus.
Function:
assists in arm flexion and adduction.
Nerve Supply:
musculocutaneous nerve (C5-C7).
Blood Supply:
brachial artery
Triceps Brachii:
Attachment:
Originates from the scapula (long head), humerus (lateral head), and humerus (medial head) and inserts into the olecranon process of the ulna.
Function:
extending the elbow joint and forearm.
Nerve Supply:
Innervated by the radial nerve (C6-C8).
Blood Supply:
deep brachial artery.
Anconeus
Attachment:
Originates from the lateral epicondyle of the humerus and inserts into the olecranon process of the ulna.
Function:
The anconeus muscle assists in elbow extension and provides stability to the elbow joint.
Nerve Supply:
Innervated by the radial nerve (C7-C8).
Blood Supply:
profunda brachii artery and posterior ulnar recurrent artery.
