Muscles of the Body Flashcards
Muscles of Facial Expression
Located in face and scalp; Produce facial movements
Insert into skin
Innervated by cranial nerve VII- Facial nerve
Muscles of Tongue
Extrinsic muscles- Move laterally, anteriorly, and posteriorly
Intrinsic muscles- Produce shape of tongue
Innervated by cranial nerve XII- Hypoglossal nerve
Muscles of Mastication
Produce chewing
Jaw closure- Masseter and temporalis
Lateral jaw movements- Pterygoid muscles
Compress cheeks- Buccinator
Innervated by cranial nerve V- Trigeminal Nerve
Masseter
Origin- Maxilla and Zygomatic Process
Insertion- Lateral angle and ramus of mandible
Function- Close jaw
Innervation- Trigeminal Nerve
Temporalis
Origin- Temporal Fossa
Insertion- Coronoid process and ramus of mandible
Function- Close jaw
Innervation- Trigeminal nerve
Buccinator
Origin- Alveolar margins
Insertion- Orbicularis oris
Function- Compress cheeks
Innervation- Facial Nerve
Muscles of Anterior Neck
Divided into sections based on the sternocleidomastoid and hyoid bone
Anterior triangle- Participate in swallowing; divided into suprahyoid and infrahyoid
Pharyngeal constrictors- force food into esophagus
Muscles of head movement
Anterior-
Sternocleidomastoid- Flex and laterally rotate head to opposite side
Scalenes- Elevate ribs 1&2 and assist in flexion and rotation of neck
Posterior-
Splenius capititis and Splenius cervicis- Extend and rotate head and neck
Deep muscles of the back
Responsible for trunk extension and maintaining spinal curves
Form column from sacrum to skull
Erector Spinae Group
Semispinalis- Extend and lateral rotation of vertebral column
Erector Spinae Muscles
Iliocostalis- Lateral
Lumborum, Thoracis, and Cervicis
Longissimus- Intermediate
Thoracis, Cervicis, and Capitis
Spinalis- Medial
Thoracis, Cervicis, and Capitis
Muscles Involved in Breathing
External Intercostals
Internal Intercostals
Diaphragm
External Intercostals
Run oblique and inferior from superior to inferior border of ribs
Elevate rib cage
Internal intercostals
Run inferior and posterior from superior to inferior border of ribs
Depress rib cage in forced exhalation
Diaphragm
Umbrella shaped muscle that divides the thoracic and abdominal cavities
Moves down and flattens during contraction and inhalation
Muscles of the Abdominal wall
External Obliques
Internal Obliques
Transversus Abdominus
Rectus Abdominus
External Obliques
Superficial abdominal wall muscle
Fascicles run down and medial
Support and compress abdomen; Trunk flexion and lateral rotation
Internal obliques
Middle abdominal wall muscle
Fascicles run down and lateral
Support and compress abdomen; Trunk flexion and lateral rotation
Transversus Abdominis
Deep abdominal wall muscles
Fascicles run horizontally
Compress abdomen
Rectus Abdominis
Traditional ab muscles
Run from pubis to rib cage
Anterior vertebral flexion
Anterior Thorax Muscles
Pectoralis Major
Pectoralis Minor
Serratus Anterior
Posterior Thorax Muscles
Trapezius
Levator Scapulae
Rhomboid major and minor
Pectoralis Major
Origin- Clavicle, Sternum, and costal cartilage
Insertion- Lateral intertubercular groove
Function- Medial rotation and adduction of arm; arm flexion
Innervation- Pectoral nerve
Pectoralis minor
Origin- Ribs 3-5
Insertion- Coracoid process
Function- Protract and rotate scapula downward, elevate ribs
Innervation- Pectoral nerve
Serratus Anterior
Origin- Ribs 1-8
Insertion- Costal medial scapular border
Function- Abduct and laterally rotate scapula downward
Innervation- Long thoracic nerve
Trapezius
Origin- Occipital bone, ligamentum nuchae, spinous process C7-T12
Insertion- Acromion, scapular spine, and clavicle
Function- Elevate, depress, adduct, and laterally rotate scapula up
Innervation- Spinal accessory nerve
Levator Scapulae
Origin- Transverse process C1-C4
Insertion- Upper medial scapular border
Function- Elevate scapula and depress glenoid cavity
Innervation- Cervical and dorsal scapular nerves
Rhomboid major
Origin- Spinous process T2-T5
Insertion- Medial border of scapula
Function- Elevate, adduct, and medially rotate scapula
Innervation- Dorsal scapular nerve
Rhomboid minor
Origin- Ligamentum nuchae, C7 + T1 spinous processes
Insertion- Medial border of scapula
Function- Elevate, adduct, and medially rotate scapula
Innervation- Dorsal scapular nerve
Muscles that produce movement of the arm
Pectoralis major
Deltoid
Latissimus Dorsi
Teres Major
Rotator Cuff
Rotator Cuff
All muscles function to stabilize the shoulder joint
Supraspinatus
Infraspinatus
Teres minor
Subscapularis
Deltoid
Prime mover of arm abduction
Functions- Abduct, flex, extend, and rotate arm
Function depends on what fibers are active
Insert into deltoid tuberosity
Innervated by axillary nerve
Latissimus dorsi
Origin- Posterior iliac crest, spinous process L5-T7, ribs 8-12
Insertion- Intertubercular groove
Function- Extend, adduct, and medially rotate arm
Innervation- Thoracodorsal nerve
Teres major
Origin- Posterior inferior angle and lower lateral border of scapula
Insertion- Intertubercular groove
Function- Adducts, medially rotates, and extends arm
Innervation- Lower subscapular nerve
Supraspinatus
Abducts and laterally rotates arm
Part of rotator cuff
Infraspinatus
Laterally rotate arm
Part of rotator cuff
Teres minor
Adduct and laterally rotate arm
Part of rotator cuff
Subscapularis
Medially rotates arm
Part of rotator cuff
Muscles crossing the elbow
Anterior:
Biceps Brachii
Brachialis
Brachioradialis
Posterior:
Triceps Brachii
Aconeus
Biceps Brachii
Origins- Supraglenoid tubercle and coracoid process
Insertion- Radial tuberosity
Function- Flex forearm, supinate forearm, assist shoulder flexion
Innervation- Musculocutaneous nerve
Brachialis
Origin- Distal anterior humerus
Insertion- Ulnar tuberosity and coronoid process
Function- Elbow flexion
Innervation- Musculocutaneous nerve
Brachioradialis
Origin- Lateral supracondylar ridge
Insertion- Styloid process of radius
Function- Flex forearm (advantage when pronated)
Innervation- Deep radial nerve
Triceps Brachii
Origins- Infraglenoid Tubercle, posterior humerus
Insertion- Olecranon process
Function- Extend forearm, weak shoulder extension
Innervation- Radial nerve
Anconeus
Assist pronation and elbow extension
Characteristics of Anterior Forearm Muscles
Flexors of wrist, hand, and fingers
Innervated by Median and Ulnar nerves
Originate from Common Flexor tendon on medial epicondyle of humerus
Superficial Anterior Forearm Muscles
Pronator teres- Proximal pronator muscle
Palmaris longus- Assists wrist flexion
Flexor carpi radialis
Flexor carpi ulnaris
Flexor digitorum superficialis
Deep Anterior Forearm Muscles
Flexor pollicis longus- Flex thumb
Flexor digitorum profundus- Flex distal interphalangeal joints
Pronator quadratus- Distal pronator muscle
Flexor Carpi Radialis
Origin- Common Flexor Tendon
Insertion- Base of metacarpals 2&3
Function- Flex and abduct wrists
Innervation- Medial nerve
Flexor Carpi Ulnaris
Origin- Common Flexor Tendon
Insertion- Pisiform, Hamate, and Metacarpal 5
Function- Flex and adduct wrist
Innervation- Ulnar nerve
Flexor Digitorum Superficialis
Origin- Common flexor tendon
Insertion- Middle phalanx of digits 2-5 (ends in loop)
Function- Flex proximal interphalangeal joints; assist flexion of wrist and metacarpophalangeal joints
Innervation- Median nerve
Posterior Forearmarm Muscles Characteristics
Extensors
Innervated by radial nerve
Common extensor tendon- Lateral epicondyle of humerus
Superficial Posterior Forearm Muscles
Brachioradialis
Extensor Carpi Radialis Longus
Extensor Carpi Radialis Brevis
Extensor Digitorum
Extensor Carpi Ulnaris
Deep Posterior Forearm Muscles
Abductor Pollicis Longus
Extensor Pollicis Longus and Brevis
Extensor Indicis
Supinator
Extensor Carpi Radialis Longus
Origin- Distal Humerus
Insertion- Metacarpal 2
Function- Extend and abduct wrist
Innervation- Radial nerve
Extensor Carpi Radialis Brevis
Origin- Common extensor tendon
Insertion- Metacarpal 3
Function- Extend and abduct wrist
Innervation- Radial nerve
Extensor Digitorum
Origin- Common extensor tendon
Insertion- Dorsum of digits 2-5
Function- Extends interphalangeal joints and metacarpophalangeal joints of digits 2-5; assists wrist extension
Innervation- Radial nerve
Extensor carpi ulnaris
Origin- Common extensor tendon
Insertion- Metacarpal 5
Function- Extend and adducts wrist
Innervation- Radial nerve
Supinator
Origin- Lateral epicondyle, Radial collateral ligament, ulna
Insertion- Superior lateral radius
Function- Supinate forearm
Innervation- Radial nerve
Intrinsic Hand Muscle Groups
Thenar muscles- Ball of thumb
Hypothenar muscles- Digit 5
Midpalmar muscles- Lumbricals, Interossei
Thenar muscles
Innervated by median nerve
Abductor pollicis brevis
Flexor pollicis brevis
Opponens pollicis
Adductor pollicis
Hypothenar muscles
Abductor digiti minimi
Flexor digiti minimi
Opponens digiti minimi
Lumbricals
Extend metacarpophalangeal joints
Palmar interossei
Adduct fingers toward midline of hand
Dorsal interossei
Abduct fingers away from midline of hand
Anterior Thigh Muscles
Flex Leg and Extend Kne; Innervated by femoral nerve
Iliopsoas
Sartorius
Quadriceps Femoris
Tensor Fascia Latae
Iliopsoas
Iliacus and Psoas Muscles
Origin- T12-L5, Superior Iliac fossa and sacrum
Insertion- Lesser trochanter
Function- Flex femur and trunk
Innervation- Femoral nerve
Sartorius
Origin- Anterior superior iliac spine
Insertion- Medial tibia
Function- Flex hip and knee, laterally rotate thigh
Innervation- Femoral nerve
Quadriceps Femoris
Primary knee extensors
Share common insertion at quadriceps tendon to tibial tuberosity
Rectus Femoris, Vastus Lateralis, Vastus Intermedialis, and Vastus Medialis
Rectus Femoris
Origin- Anterior Superior Iliac Spine
Function- Flex thigh and extend knee
Vastus Lateralis
Origin- Greater trochanter
Function- Extend knee
Vastus Intermedialis
Origin- Intertrochanteric line
Function- Extend knee
Vastus Medialis
Origin- Anterior and lateral femur
Function- Extend knee
Medial Thigh Muscles
Responsible for Adduction
Adductor longus
Adductor brevis
Adductor magnus
Pectineus
Gracilis
Posterior Thigh Muscles
Extend thigh and flex knee
Gluteal Muscles (Maximus, medius, minimus)
Lateral Rotators
Hamstrings
Gluteus Maximus
Origin- Ilium, sacrum, coccyx, and sacrotuberous ligaments
Insertion- Gluteal tuberosity
Functions- Extend and laterally rotate hip
Innervation- Inferior gluteal nerve
Gluteus Medius
Origin- Posterior Ilium
Insertion- Lateral greater trochanter
Function- Abducts and medially rotates thigh; stabilizes hip
Innervation- Superior gluteal nerve
Lateral rotators
Piriformis
Obturator externus and internus
Superior and Interior gemellus
Quadratus femoris
Hamstrings Muscles
Biceps femoris
Semimembranosus
Semitendinosus
Biceps Femoris
Origin- Ischial tuberosity and supracondylar line
Insertion- Fibular head and lateral condyle of femur
Function- Flex and laterally rotate knee; weak hip extension
Innervation- Tibial nerve
Semimembranosus
Origin- Ischial tuberosity
Insertion- Posterior medial condyle of tibia
Function- Extend hip, flex and medially rotate knee
Insertion- Tibial nerve
Semitendinosus
Origin- Ischial tuberosity
Insertion- Medial tibia
Function- Extend hip, flex and medially rotate knee
Innervation- Tibial nerve
Anterior Leg Muscles
Dorsiflexors
Innervated by Deep Fibular Nerve
Tibialis Anterior
Extensor Digitorum Longus
Extensor Hallucis Longus
Fibularis Tertius- Help with eversion (if present)
Tibialis Anterior
Origin- Lateral condyle and shaft of tibia
Insertion- Medial cuneiform and metatarsal 1
Function- Dorsiflexion and inversion
Extensor Digitorum Longus
Origin- Tibial lateral condyle and anterior fibula
Insertion- Digits 2-5
Function- Extend all toe joints 2-5, assist dorsiflexion
Extensor Hallucis Longus
Origin- Anterior fibula
Insertion- Distal phalanx of digit 1
Function- Extend all joints of digit 1 and assist dorsiflextion
Lateral Muscles of the Leg
Fibularis Brevis
Fibularis Longus
Origin- Lateral fibular head
Insertion- Lateral metatarsal 1 and sole of medial cuneiform
Function- Eversion and assist plantar flexion
Innervation- Superficial fibular nerve
Posterior Muscles of the Leg
Plantar Flexors
Innervated by the Tibial Nerve
Superficial:
Triceps Surae (Gastrocnemius and soleus)
Plantaris- Assist plantar flexion
Deep:
Popliteus- Medially rotate tibia
Tibialis Posterior
Flexor Digitorum Longus
Flexor Hallucis Longus
Gastrocnemius
Origin- Medial condyle, lateral condyle, and posterior femur
Insertion- Calcaneal tendon
Function- Plantar flexion and assist knee flexion
Innervation- Tibial nerve
Soleus
Origin- Proximal posterior fiblula
Insertion- Calcaneal tendon
Function- Plantar flexion
Innervation- Tibial nerve
Tibialis Posterior
Origin- Posterior tibia, fibula, and interosseous membrane
Insertion- Navicular, cuneiforms, and base of metatarsals 2-4
Function- Inversion and plantar flexion
Innervation- Tibial nerve
Flexor Digitorum Longus
Origin- Posterior tibia
Insertion- Base of distal phalanx of digits 2-5
Function- Flex all joints of digits 2-5, assist plantar flexion
Innervation- Tibial Nerve
Flexor Hallucis Longus
Origin- Posterior fibula
Insertion- Base of distal phalanx of digit 1
Function- Flex all joints of digit 1 and assist plantar flexion
Innervation- Tibial nerve
Intrinsic Foot Muscles
Function to move toes and maintain arches
4 layers on sole side
Extensor Digitorum Brevis on dorsal side
1st layer of sole muscles
Flexor digitorum brevis
Abductor hallucis
Abductor digiti minimi
2nd layer of sole muscles
Flexor accessorius- Attach to flexor digitorum longus tendon
Lumbricals- flex metatarsophalangeal joints
3rd layer of sole muscles
Flexor hallucis brevis
Adductor hallucis
Flexor digiti minimi brevis
4th layer of sole muscles
Plantar interossei- Adduct toes toward midline of foot
Dorsal interossei- Abduct toes away from midline of foot
