Muscle Anatomy

upper trapezius

-Nerve:accessory nerve (motor)

-Actions: scapula eleavtion

-origin occipital bone, nuchal ligament on upper cervical spinous processes

-insertion outer third of clavicle, acrominon process

trapezius

-Origin spinous processes of vertebrae C1-T12

-Insertion external occipital protuberance, nuchal ligament, medial superior nuchal line, posterior border of the lateral third of the clavicle, acromion process, and spine of scapula

-Nerve accessory nerve (motor)

cervical spinal nerves C3 and C4 (motor and sensation)

-Actions rotation, retraction, elevation, and depression of scapula

-Antagonist

=serratus anterior muscle,

=Latissimus dorsi

levator scapulae

-Origin:Posterior tubercles of transverse processes of C1 - C4 vertebrae

-Insertion:Superior part of medial border of scapula

-Nerve cervical nerve; (C3, C4) and dorsal scapular nerve (C5)

-Actions: Elevates scapula and downward rotation

latissimus dorsi

-Origin: Spinous processes of vertebrae T7-L5, thoracolumbar fascia, iliac crest, inferior 3 or 4 ribs and inferior angle of scapula

-Insertion:Floor of intertubercular groove of the humerus

-Nerve: Thoracodorsal nerve

-Actions: Adducts, extends and internally rotates the arm when the insertion is moved towards the origin.

-Antagonist: Deltoid and trapezius muscle

pectoralis major

-Origin:

=Clavicular head: anterior border of the medial half of the clavicle.

=Sternocostal head: anterior surface of the sternum, the superior six costal cartilages, and the aponeurosis of the external oblique muscle

-Insertion: Lateral lip of the bicipital groove of the humerus

(anteromedial proximal humerus)

-Nerve: lateral pectoral nerve and medial pectoral nerve

=Clavicular head: C5 and C6

=Sternocostal head: C7, C8 and T1

-Actions:

=Clavicular head: flexes the humerus

=Sternocostal head: extends the humerus. As a whole, adducts and medially rotates the humerus. It also draws the scapula anteriorly and inferiorly.

pectoralis minor

-Origin; Third to fifth ribs, near their costal cartilages

-Insertion: Medial border and superior surface of the coracoid process of the scapula

-Nerve: Medial pectoral nerve (C8, T1)

-Actions: Stabilizes the scapula by drawing it inferiorly and anteriorly against the thoracic wall, raises ribs in inspiration

lower trapezius

-O: spinous processes of middle and lower thoracic vertebra

-I:spine medial nagle

-F: depression of scapula

serratus anterior

-Origin: fleshy slips from the outer surface of upper 8 or 9 ribs

-Insertion: costal aspect of medial margin of the scapula

-Nerve: long thoracic nerve (from roots of brachial plexus C5, 6, 7)

-Actions: protracts and stabilizes scapula, assists in upward rotation.

-Antagonist: Rhomboid major, Rhomboid minor, Trapezius

rhomboids

-Origin nuchal ligaments, spinous processes of the C7 to T5 vertebrae

-Insertion medial border of the scapula

-Nerve dorsal scapular nerve

-Actions

deltoid

-Origin the anterior border and upper surface of the lateral third of the clavicle, acromion, spine of the scapula

-Insertion deltoid tuberosity of humerus

-Nerve Axillary nerve

-Actions shoulder abduction by middle deltoid, flexion by anterior deltoid and extension by posterior deltoid

-Antagonist Latissimus dorsi

biceps brachii

-Origin

=Short head: coracoid process of the scapula.

=Long head: supraglenoid tubercle

-Insertion Radial tuberosity and bicipital aponeurosis into deep fascia on medial part of forearm

-Nerve Musculocutaneous nerve (C5-C7)

-Actions

=Flexes elbow,

=supinates radioulnar joint in the forearm

-Antagonist Triceps brachii muscle

bicipital aponeurosis

triceps

-Origin

=Long head: infraglenoid tubercle of scapula

=Lateral head: above the radial sulcus

=Medial head: below the radial sulcus

-Insertion Olecranon process of ulna

-Nerve Radial nerve

-Actions

= Extends forearm,

= long head extends,adducts arm, Extends shoulder

-Antagonist Biceps brachii muscle

teres major

-Origin Posterior aspect of the inferior angle of the scapula

-Insertion Medial lip of the intertubercular sulcus of the humerus

-Nerve Lower subscapular nerve (segmental levels C5 and C6)

-Actions

= adduct the humerus,

= Internal rotation (medial rotation) of the humerus

= extend the humerus from flexed position,

teres minor

-Origin lateral border of the scapula

-Insertion inferior facet of greater tubercle of the humerus

-Nerve axillary nerve

-Actions laterally rotates the arm, stabilizes humerus

supraspinatus

-Origin supraspinous fossa of scapula

-Insertion superior facet of greater tubercle of humerus

-Nerve suprascapular nerve

-Actions abduction of arm and stabilizes humerus

infraspinatus

-Origin infraspinous fossa of the scapula

-Insertion middle facet of greater tubercle of the humerus

-Nerve suprascapular nerve

-Actions Lateral rotation of arm and stabilizes humerus

subscapularis

-Origin Subscapular fossa

-Insertion Lesser tubercle of humerus

-Nerve Upper subscapular nerve, lower subscapular nerve (C5, C6)

-Actions Internally (medially) rotates humerus and stabilizes shoulder

Subscapular fossa

subscapular fossa is a feature on the scapula bone, which is also known as the shoulder bone (or shoulder blade)

rectus abdominis

-Origin crest of pubis

-Insertion

=Costal cartilage of ribs 5-7,

=xiphoid process of sternum

-Nerve segmentally by thoraco-abdominal nerves (T7 to T11)

-Actions Flexion of the lumbar spine

-Antagonist Erector spinae

internal oblique

-Origin Inguinal ligament, Iliac crest and the Lumbodorsal fascia.

-Insertion Linea alba, Pecten Pubis (via Conjoint tendon) and ribs 10-12.

-Actions

= Compresses abdomen

=unilateral contraction rotates vertebral column to same side.

external oblique

-Origin Ribs 5-12

-Insertion Iliac crest, Pubic tubercle, Linea alba

-Actions Contralateral rotation of torso

brachialis

-Origin anterior surface of the humerus, particularly the distal half of this bone

-Insertion coronoid process and the tuberosity of the ulna

-Nerve musculocutaneous nerve (C5, C6)

-Actions flexion at elbow joint

brachioradialis

-Origin Lateral supracondylar ridge of the humerus

-Insertion Distal radius (radial styloid process)

-Nerve :Radial nerve

-Actions :Flexion of elbow and supination

supinator

-Origin Lateral epicondyle of humerus, supinator crest of ulna, radial collateral ligament, annular ligament

-Insertion Lateral proximal radial shaft

-Nerve Deep branch of the radial nerve

-Actions Supinates forearm

-Antagonist Pronator teres, pronator quadratus

pronator teres

-Origin

=humeral head: medial supracondylar ridge of humerus (common flexor tendon)

=ulnar head: coronoid process of ulna

-Insertion Middle of the lateral surface of the body of the radius

-Nerve median nerve

-Actions pronation of forearm, flexes elbow

-Antagonist Supinator muscle

flexor carpi radialis

-Origin medial epicondyle of humerus (common flexor tendon)

-Insertion Bases of second and third metacarpal bones

-Nerve Median nerve

-Actions Flexion and abduction at wrist

-Antagonist Extensor carpi ulnaris muscle

flexor carpi ulnaris

-Origin Medial epicondyle (common flexor tendon) and medial margin on olecranon of ulna

-Insertion Pisiform, hook of the hamate, base of the fifth metacarpal bone

-Nerve ulnar nerve

Nerve root C7, C8 and T1

-Actions Flexion and adduction of wrist

-Antagonist Extensor carpi radialis brevis muscle and extensor carpi radialis longus muscle

extensor carpi radialis longus

-Origin lateral supracondylar ridge

-Insertion 2nd metacarpal

-Nerve radial nerve

-Actions extensor at the wrist joint, abducts the hand at the wrist

-Antagonist Flexor carpi ulnaris muscle

Extensor carpi radialis brevis

extensor carpi ulnaris

-Origin Common extensor tendon (lateral epicondyle), ulna

-Insertion 5th metacarpal

-Nerve Deep branch of the radial nerve (C7, C8)

-Actions extends and adducts the wrist

-Antagonist Flexor carpi radialis

palmaris longus

-Origin medial epicondyle of humerus (common flexor tendon)

-Insertion palmar aponeurosis

-Nerve median nerve

-Actions wrist flexor

-Antagonist Extensor carpi radialis brevis, Extensor carpi radialis longus, Extensor carpi ulnaris

iliopsoas

-Origin Iliac fossa and lumbar spine

-Insertion Lesser trochanter of femur

-Nerve Branches from L1-L3

-Actions Flexion of hip

-Antagonist Gluteus maximus and the posterior compartment of thigh

sartorius

-Origin Anterior superior iliac spine of the pelvic bone

-Insertion anteromedial surface of the upper tibia in the pes anserinus

-Nerve femoral nerve (sometimes from the intermediate cutaneous nerve of thigh)

-Actions Flexion, abduction, and lateral rotation of the hip, flexion of the knee

-tailor's muscle and longest.

rectus femoris

-Origin anterior inferior iliac spine and the exterior surface of the bony ridge which forms the groove on the iliac portion of the acetabulum

-Insertion inserts into the patellar tendon as one of the four quadriceps muscles

-Nerve femoral nerve

-Actions knee extension; hip flexion

-Antagonist Hamstring

piriformis

-Origin Sacrum

-Insertion Greater trochanter

-Nerve Nerve to the piriformis (L5, S1, and S2)

-Actions External rotator of the thigh

gracilis

-Origin ischiopubic ramus

-Insertion tibia (pes anserinus)

-Nerve anterior branch of obturator nerve

-Actions flexes, medially rotates, and adducts the hip,

pectinus

-Origin Pectineal line of the pubic bone

-Insertion Pectineal line of the femur

-Nerve Femoral nerve, sometimes obturator nerve

-Actions flexion and adduction of thigh

tensor fascia latae

-Origin Iliac crest

-Insertion Iliotibial tract

-Nerve Superior gluteal nerve (L4, L5, S1)

-Actions

=Hip; flexion, medial rotation, abduction

*hamstring*

-Origin tuberosity of the ischium, linea aspera

-Insertion tibia, fibula

-Nerve: sciatic nerve (tibial nerve and common fibular nerve)

-Actions: flexion of knee, extension of hip

-Antagonist: Rectus femoris muscle

biceps femoris

-Origin tuberosity of the ischium, linea aspera, femur

-Insertion the head of the fibula which articulates with the back of the lateral tibial condyle

-Nerve

=long head: tibial nerve

=short head: common fibular nerve

-Actions

=flexes knee joint,

=laterally rotates knee joint (when knee is flexed),

=extends hip joint (long head only)

-Antagonist Quadriceps muscle

semitendinosus

-Origin Tuberosity of the ischium

-Insertion Pes anserinus (tibia)

-Nerve Sciatic (tibial, L5, S1, S2)

-Actions Flexion of knee, extension of the hip joint

-Antagonist Quadriceps muscle

semimembranosus

-Origin Ischial tuberosity

-Insertion Medial condyle of tibia

-Nerve Tibial part of sciatic nerve

(L5, S1 and S2)

-Actions Extension of hip and flexion of knee

-Antagonist Quadriceps muscle and Tensor fasciae latae

*quadriceps*

-Origin Combined rectus: femoris and vastus muscles

-Insertion: Tibial tuberosity

-Nerve: Femoral nerve

-Actions

=Knee extension

=Hip flexion (Rectus femoris only)

vastus lateralis

-Origin Greater trochanter, Intertrochanteric line, and Linea aspera of the Femur

-Insertion Patella via the Quadriceps tendon and Tibial tuberosity via the Patellar ligament

-Nerve femoral nerve

-Actions Extends and stabilizes knee

-Antagonist Hamstring

vastus intermedius

-Origin antero/ lateral femur

-Insertion Quadriceps tendon

-Nerve femoral nerve

-Actions Extension of knee joint

vastus medialis

-Origin Medial side of femur

-Insertion Quadriceps tendon

-Nerve Femoral nerve

-Actions Extends leg

*gluteus maximus*

-Origin Gluteal surface of ilium, lumbar fascia, sacrum, sacrotuberous ligament

-Insertion Gluteal tuberosity of the femur and iliotibial tract

-Nerve Inferior gluteal nerve (L5, S1 and S2 nerve roots)

-Actions

=External rotation and extension of the hip joint

=chief antigravity muscle in sitting and abduction of the hip

-Antagonist iliopsoas

*gluteus medius*

-Origin Gluteal surface of ilium, under gluteus maximus

-Insertion Greater trochanter of the femur

-Nerve superior gluteal nerve (L4, L5, S1 nerve roots)

-Actions

=abduction of the hip

=Medial rotation of thigh.

-Antagonist adductors

gluteus minimus

-Origin From area in between the anterior gluteal line and inferior gluteal line of Gluteal surface ilium, under gluteus medius.

-Insertion Greater trochanter of the femur

-Nerve superior gluteal nerve (L4, L5, S1 nerve roots)

-Actions

=Works in concert with gluteus medius: abduction of the hip

=Medial rotation of thigh.

-Antagonist lateral rotator group

*tibialis posterior*

-Origin Tibia and fibula

-Insertion: Navicular and medial cuneiform bone

-Nerve Tibial nerve

-Actions

=Inversion of the foot.

-Antagonist Fibularis brevis

soleus

-Origin fibula, medial border of tibia (soleal line)

=Insertion tendo calcaneus

-Nerve tibial nerve, specifically, nerve roots L5-S2

-Actions plantarflexion

-Antagonist tibialis anterior

triceps surae

calf muscle:gcm, soleus, achilles tendon

peroneus longus

-Origin Upper lateral shaft of fibula

-Insertion first metatarsal, medial cuneiform

[same insertion as Tibialis Anterior]

-Nerve Superficial fibular (peroneal) nerve

-Actions plantarflexion, eversion,

-Antagonist Tibialis anterior muscle that does Inversion and Dorsiflexion

peroneus brevis

-Origin Lower two-thirds of lateral fibula

-Insertion Fifth metatarsal

-Nerve Superficial fibular nerve

-Actions Plantarflexion, eversion

peroneus tertius

-Origin distal anterior surface of the fibula also the interosseous membrane

-Insertion dorsal surface of metatarsal 5

-Nerve deep fibular nerve

-Actions dorsiflexion and eversion of the foot

plantaris

-Origin: Lateral supracondylar ridge of femur above lateral head of gastrocnemius

-Insertion: Tendon calcaneus (medial side, deep to gastrocnemius tendon)

-Nerve tibial nerve from S1-S2

-Actions Plantar flexes foot and flexes knee

-Antagonist Tibialis anterior muscle

tibialis anterior

-Origin Upper 1/2 & Lateral Condyle of Tibia

-Insertion medial cuneiform and first metatarsal bones of the foot

-Nerve: Deep Fibular (peroneal) nerve (L5)

-Actions Dorsiflexion and Inversion of the foot

-Antagonist Fibularis longus, Gastrocnemius, Soleus, Plantaris, Tibialis posterior

extensor digitorum longus

-Origin Anterior lateral condyle of tibia, anterior shaft of fibula and superior 3⁄4 of interosseous membrane

-Insertion: Dorsal surface; middle and distal phalanges of lateral four digits

-Nerve deep fibular nerve

-Actions

=extension of toes

=dorsiflexion of ankle

-Antagonist Flexor digitorum longus, Flexor digitorum brevis

Extensor digitorum muscle

Origin lateral epicondyle (common extensor tendon)

Insertion extensor expansion of middle and distal phalanges of the 2nd, 3rd, 4th, and 5th fingers[1]

Nerve radial nerve

Actions extension of hand, wrist and fingers

Antagonist Flexor digitorum superficialis muscle, Flexor digitorum profundus muscle

Flexor digitorum superficialis

Origin medial epicondyle of the humerus (common flexor tendon) as well as parts of the radius and ulna.

Insertion anterior margins on the bases of the middle phalanges of the four fingers

Nerve median nerve

Actions flexor of fingers (primarily at proximal interphalangeal joints)

Antagonist Extensor digitorum muscle