What is the primary action of the Extensor Digitorum?
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Extends wrist joint and medial four fingers primarily at metacarpophalangeal joints.
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What is the primary action of the Extensor Digitorum?
Extends wrist joint and medial four fingers primarily at metacarpophalangeal joints.
Where does the Extensor Digitorum originate?
Lateral epicondyle of the humerus (common extensor origin).
What is the action of the Extensor Digiti Minimi?
Extends the 5th finger primarily at the metacarpophalangeal joint.
What is the origin of the Superior Gemellus muscle?
Ischial spine.
What is the innervation of the Extensor Carpi Ulnaris?
Posterior interosseous nerve (C7, C8), continuation of deep branch of radial nerve.
Which nerve innervates the Superior Gemellus?
Nerve to obturator internus (L5, S1).
What is the origin of the Adductor Longus muscle?
Body of pubis inferior to pubic crest.
What is the action of the Extensor Carpi Ulnaris?
Extends and adducts wrist joint and carpometacarpal joints.
What is the insertion point of the Inferior Gemellus?
Medial surface of greater trochanter (trochanteric fossa) of femur.
What is the primary action of the Adductor Longus?
Adducts hip joint.
What is the origin of the Supinator muscle?
Lateral epicondyle of the humerus, radial collateral and anular ligaments, supinator fossa.
What action does the Quadratus Femoris perform?
Laterally rotates hip joint; stabilizes hip joint.
Which nerve innervates the Adductor Brevis?
Obturator nerve (L2, L3, L4).
What is the primary action of the Supinator?
Supinates forearm; rotates radius to turn palm anteriorly or superiorly.
What is the origin of the Biceps Femoris Long Head?
Ischial tuberosity.
What are the actions of the Adductor Brevis?
Adducts hip joint and to some extent flexes it.
Where does the Supinator insert?
Lateral, posterior, and anterior surfaces of proximal third of radius.
What is the innervation of the Biceps Femoris Short Head?
Common fibular division of sciatic nerve (L5, S1, S2).
What is the origin of the Adductor Magnus muscle?
Adductor part: inferior ramus of pubis, ramus of ischium; Hamstring part: ischial tuberosity.
What is the primary action of the Semitendinosus?
Extend hip joint; flex knee joint and medially rotate it when flexed.
What is the action of the Hamstring part of the Adductor Magnus?
Extends the hip joint.
Where does the Semimembranosus insert?
Posterior part of medial condyle of tibia.
What is the insertion point of the Gracilis muscle?
Superior part of medial surface of tibia (as part of pes anserinus).
What is the origin of the Pectoralis major's clavicular head?
Anterior surface of the medial half of the clavicle.
What is the innervation for the Semitendinosus?
Tibial division of sciatic nerve (L5, S1, S2).
What is the primary action of the Sartorius muscle?
Thigh flexion, thigh abduction, and thigh external rotation at the hip joint; leg flexion and leg internal rotation at the knee joint.
What is the insertion point of the Pectoralis major?
Lateral lip of the intertubercular sulcus of the humerus.
What actions does the Gracilis perform?
Adducts hip joint; flexes knee joint, medially rotating it when flexed.
Where does the Sartorius muscle originate?
Anterior superior iliac spine (ASIS).
What is the origin of the Quadratus plantae muscle?
Medial surface of calcaneus bone and lateral process of calcaneal tuberosity.
What nerves innervate the Pectoralis major?
Lateral and medial pectoral nerves; clavicular head (C5, C6), sternocostal head (C7, C8, T1).
What is the origin of the Obturator Externus muscle?
Margins of obturator foramen and obturator membrane.
What is the origin of the Fibularis tertius?
Medial surface (distal third) of fibula, interosseous membrane (anterior surface), anterior intermuscular septum.
What are the origins of the Psoas major muscle?
Vertebral bodies of T12-L4, intervertebral discs between T12-L4, and transverse processes of L1-L5 vertebrae.
Where does the Sartorius muscle insert?
Proximal end of tibia below medial condyle (via pes anserinus).
What is the action of the Quadratus plantae?
Toe flexion at metatarsophalangeal joints 2-5.
What is the primary action of the Iliopsoas muscle?
Flexes thigh/trunk at the hip joint.
What actions does the Pectoralis major perform?
Adducts and medially rotates the shoulder joint; draws scapula anteriorly and inferiorly.
What is the origin of the Psoas minor muscle?
Vertebral bodies of T12 & L1 vertebrae.
What nerve innervates the Sartorius muscle?
Femoral nerve (L2-L3).
What is the insertion point of the Fibularis tertius?
Dorsal surface of base of metatarsal bone 5.
What is the innervation of the Lumbricals?
Lumbrical 1: Medial plantar nerve (S2, S3); Lumbricals 2-4: Lateral plantar nerve (S2-S3).
What is the origin of the Pectoralis minor?
3rd–5th ribs near their costal cartilages.
What is the primary action of the Tibialis anterior muscle?
Foot dorsiflexion at the talocrural joint and foot inversion at the subtalar joint.
What is the common insertion point for the iliopsoas tendon?
Lesser trochanter of the femur.
What actions does the Fibularis tertius perform?
Dorsiflexion of the foot at the talocrural joint and eversion at the subtalar joint.
What actions do the Lumbricals perform?
Toe flexion and adduction at metatarsophalangeal joints 2-5; toe extension at interphalangeal joints 2-5.
What is the action of the Pectoralis minor?
Stabilizes scapula by drawing it inferiorly and anteriorly against the thoracic wall.
Where does the Tibialis anterior muscle originate?
Lateral surface of tibia and interosseous membrane.
What is the origin of the Rectus abdominis?
Pubic symphysis and pubic crest.
What spinal nerves innervate the Psoas major?
Anterior rami of spinal nerves L1-L3.
What is the innervation of the Extensor hallucis longus?
Deep fibular nerve (L5, S1).
What is the origin of the Flexor hallucis brevis?
Tendon of tibialis posterior, medial cuneiform bone, lateral cuneiform bone, cuboid bone.
What is the origin of the Subclavius muscle?
Junction of the 1st rib and its costal cartilage.
What actions does the Psoas major perform at the hip joint?
Flexion of the thigh/trunk and lateral rotation of the thigh.
Where does the Tibialis anterior muscle insert?
Medial cuneiform bone and base of metatarsal bone 1.
What is the origin of the Abductor Pollicis Longus?
Posterior surface of proximal halves of ulna, radius, and interosseous membrane.
What is the insertion point of the Rectus abdominis?
Xiphoid process and 5th–7th costal cartilages.
What is the origin of the Fibularis longus?
Middle third of medial surface of fibula, interosseous membrane.
What is the action of the Flexor hallucis brevis?
Toe flexion at metatarsophalangeal joint 1 and support of the longitudinal arch of the foot.
What is the action of the Subclavius?
Anchors and depresses the clavicle.
What is the origin of the Rectus femoris muscle?
Anterior inferior iliac spine and supraacetabular groove.
What is the action of the supraspinatus muscle?
Initiates and assists deltoid in abduction of the shoulder joint.
What is the action of the Abductor Pollicis Longus?
Extends wrist joint, carpometacarpal joints; abducts thumb and extends it at carpometacarpal joint.
What nerve innervates the Tibialis anterior muscle?
Deep fibular nerve (L4, L5).
What is the insertion point of the Fibularis longus?
Base of distal phalanx of great toe.
What is the primary action of the Rectus abdominis?
Flexes trunk and compresses abdominal viscera.
What is the innervation of the Adductor hallucis?
Lateral plantar nerve (S2, S3).
What is the origin of the Serratus anterior?
External surfaces of lateral parts of the 1st–8th ribs.
Where does the Vastus medialis muscle originate?
Intertrochanteric line, pectineal line of femur, linea aspera, and medial supracondylar line of femur.
Where does the supraspinatus originate?
Supraspinous fossa of the scapula.
What actions does the Fibularis longus perform?
Toe extension at metatarsophalangeal and interphalangeal joint 1; dorsiflexion at the talocrural joint.
Where does the Extensor Pollicis Longus insert?
Dorsal aspect of base of distal phalanx of thumb.
What is the primary action of the Extensor digitorum longus muscle?
Toe extension at metatarsophalangeal and interphalangeal joints 2-5; foot dorsiflexion at the talocrural joint; foot eversion at the subtalar joint.
What are the actions of the Adductor hallucis?
Toe adduction and flexion at metatarsophalangeal joint 1; support of longitudinal and transverse arches of the foot.
What nerves innervate the Rectus abdominis?
Thoracoabdominal and subcostal nerves (anterior rami of T7–T12 spinal nerves).
What is the action of the Serratus anterior?
Protracts scapula and holds it against the thoracic wall; rotates scapula.
What is the common insertion point for the Quadriceps femoris group?
Tibial tuberosity via patellar ligament and patella.
Which nerve innervates the supraspinatus?
Suprascapular nerve (C4, C5, C6).
What is the origin of the Fibularis brevis?
Distal 2/3 of the lateral surface of fibula, anterior intermuscular septum.
What is the origin of the Flexor digiti minimi brevis?
Base of metatarsal bone 5 and long plantar ligament.
What is the function of the Extensor Pollicis Longus?
Extends wrist joint, carpometacarpal joints; extends distal phalanx of thumb at interphalangeal joint.
What is the origin of the Latissimus dorsi?
Spinous processes of the inferior six vertebrae.
What is the origin of the External oblique?
External surfaces of 5th–12th ribs.
Where does the Extensor digitorum longus muscle originate?
Proximal half of medial surface of fibula, lateral tibial condyle, and interosseous membrane.
What is the origin of the Flexor carpi ulnaris?
Olecranon and posterior border of ulna (via aponeurosis).
What actions does the Rectus femoris perform at the hip and knee joints?
Thigh flexion at the hip joint and leg extension at the knee joint.
What is the action of the infraspinatus muscle?
Laterally rotates the shoulder joint.
What is the origin of the Extensor Pollicis Brevis?
Posterior surface of distal third of radius and interosseous membrane.
What is the insertion point of the Fibularis brevis?
Tuberosity of the 5th metatarsal bone.
What is the action of the Latissimus dorsi?
Extends, adducts, and medially rotates the shoulder joint.
What is the action of the Flexor digiti minimi brevis?
Toe flexion at metatarsophalangeal joint 5.
What is the insertion point of the External oblique?
Linea alba, pubic tubercle, and anterior half of iliac crest.
What is the insertion point of the Flexor carpi ulnaris?
Pisiform, hook of hamate, 5th metacarpal.
Where does the Extensor digitorum longus muscle insert?
Distal and middle phalanges of digits 2-5.
What is the origin of the Pectineus muscle?
Superior pubic ramus (pectineal line of pubis).
Where does the infraspinatus originate?
Infraspinous fossa of the scapula.
What action does the Extensor Pollicis Brevis perform?
Extends proximal phalanx of thumb at metacarpophalangeal joint; extends carpometacarpal joint.
What actions does the Fibularis brevis perform?
Plantar flexion at the talocrural joint and eversion at the subtalar joint.
What is the primary action of the External oblique?
Compress and support abdominal viscera; flex and rotate trunk.
Which nerve innervates the Flexor carpi ulnaris?
Ulnar nerve (C7, C8).
What actions does the Pectineus muscle perform?
Thigh flexion, thigh adduction, and thigh external rotation.
What is the origin of the medial head of the gastrocnemius?
Popliteal surface of femur, superior to medial condyle.
Which nerve innervates the infraspinatus?
Suprascapular nerve (C5, C6).
Where does the Extensor Indicis originate?
Posterior surface of distal third of ulna and interosseous membrane.
What is the origin of the Gastrocnemius?
Lateral head: lateral aspect of lateral condyle of femur.
What is the origin of the Internal oblique?
Thoracolumbar fascia, anterior two thirds of iliac crest, and connective tissue deep to inguinal ligament.
What action does the Flexor carpi ulnaris perform?
Flexes and adducts hand at wrist.
What action does the medial head of the gastrocnemius perform?
Raises heel during walking and flexes knee joint.
What is the primary action of the Extensor Indicis?
Extends 2nd finger (enabling its independent extension); helps extend hand at wrist.
What is the action of the teres minor muscle?
Laterally rotates the shoulder joint.
What is the insertion point of the Internal oblique?
Inferior borders of 10th–12th ribs, linea alba, and pubis via conjoint tendon.
What action does the Gastrocnemius perform?
Plantarflexes the ankle joint when the knee joint is extended.
What is the origin of the Flexor digitorum superficialis?
Humeroulnar head: medial epicondyle of humerus and coronoid process of ulna; Radial head: oblique line of radius.
Where does the soleus originate?
Soleal line, medial border of tibia, head of fibula, posterior border of fibula.
Where does the teres major originate?
Inferior part of the lateral border of the scapula.
What is the primary action of the Internal oblique?
Compress and support abdominal viscera; flex and rotate trunk.
What is the insertion point of the Flexor digitorum superficialis?
Shafts (bodies) of middle phalanges of medial four digits.
What is the primary action of the soleus?
Plantarflexes ankle joint and stabilizes ankle joint.
What is the action of the teres major muscle?
Adducts and medially rotates the shoulder joint.
What is the origin of the Transversus abdominis?
Internal surfaces of 7th–12th costal cartilages, thoracolumbar fascia, iliac crest, and connective tissue deep to inguinal ligament.
Which nerve innervates the Flexor digitorum superficialis?
Median nerve (C7, C8, T1).
What is the origin of the Coracobrachialis muscle?
Tip of the coracoid process of the scapula.
What is the origin of the plantaris muscle?
Inferior end of lateral supracondylar line of femur and oblique popliteal ligament.
What is the insertion point of the Transversus abdominis?
Linea alba with aponeurosis of internal oblique, pubic crest, and pubis via conjoint tendon.
What actions does the Flexor digitorum superficialis perform?
Flexes wrist joint, carpometacarpal joints, and proximal interphalangeal joints of middle four digits.
Where does the subscapularis muscle originate?
Subscapular fossa (most of the anterior surface of the scapula).
Where does the Coracobrachialis insert?
Middle third of the medial surface of the humerus.
What is the action of the plantaris muscle?
Weakly assists gastrocnemius in plantarflexing ankle joint; mainly proprioceptive.
What is the primary action of the Transversus abdominis?
Compresses and supports abdominal viscera.
What is the origin of the Flexor digitorum profundus?
Proximal three quarters of medial and anterior surfaces of ulna and interosseous membrane.
What is the action of the biceps brachii?
Supinates forearm and flexes elbow joint when supinated.
Which nerve innervates the Coracobrachialis?
Musculocutaneous nerve (C5, C6, C7).
Where does the popliteus muscle insert?
Posterior surface of tibia superior to soleal line.
What is the insertion point of the Flexor digitorum profundus?
Bases of distal phalanges of 2nd, 3rd, 4th, and 5th digits.
What is the origin of the Trapezius muscle?
Medial third of superior nuchal line, external occipital protuberance, nuchal ligament, spinous processes of C7–T12 vertebrae.
Where does the biceps brachii insert?
Tuberosity of the radius and fascia of forearm via bicipital aponeurosis.
What are the actions of the popliteus muscle?
Plantar flexion of the foot at the talocrural joint and knee flexion.
What actions does the Coracobrachialis perform?
Helps flex and adduct the shoulder joint; resists dislocation of the shoulder.
Which nerves innervate the Flexor digitorum profundus?
Lateral part (to digits 2 and 3): median nerve (C8, T1); Medial part (to digits 4 and 5): ulnar nerve (C8, T1).
What is the insertion point of the Trapezius muscle?
Lateral third of clavicle, acromion, and spine of scapula.
What is the action of the brachialis muscle?
Flexes elbow joint in all positions.
What is the origin of the flexor digitorum longus?
Posterior surface of tibia (inferior to soleal line).
What is the origin of the Long head of the Triceps brachii?
Infraglenoid tubercle of the scapula.
What actions does the Flexor digitorum profundus perform?
Flexes wrist joint, carpometacarpal joints, and distal interphalangeal joints of digits 2, 3, 4, and 5.
Which nerves innervate the Trapezius muscle?
Spinal accessory nerve (CN XI; motor fibers) and C3, C4 spinal nerves (pain and proprioceptive fibers).
Where does the brachialis originate?
Distal half of the anterior surface of the humerus.
What actions does the flexor digitorum longus perform?
Toe flexion at metatarsophalangeal and interphalangeal joints 2-5; plantar flexion at talocrural joint; foot inversion at subtalar joint.
Where does the Triceps brachii insert?
Proximal end of the olecranon of the ulna and fascia of the forearm.
What actions does the Trapezius muscle perform?
Elevates, depresses, and retracts scapula; rotates glenoid cavity superiorly.
Where does the flexor hallucis longus originate?
Distal 2/3 of posterior surface of fibula, interosseous membrane, posterior intermuscular septum of leg, fascia of tibialis posterior muscle.
Which nerve innervates the Triceps brachii?
Radial nerve (C6, C7, C8).
What is the origin of the Levator scapulae muscle?
Posterior tubercles of transverse processes of C1–C4 vertebrae.
What is the action of the flexor hallucis longus?
Toe flexion at metatarsophalangeal and interphalangeal joint 1; plantar flexion at talocrural joint.
What is the origin of the Gluteus maximus?
Ilium posterior to posterior gluteal line; posterior surface of sacrum and coccyx; and sacrotuberous ligament.
What is the primary action of the Triceps brachii?
Chief extensor of the elbow joint; long head extends the shoulder joint and resists dislocation of the humerus.
What is the insertion point of the Levator scapulae muscle?
Medial border of scapula superior to root of spine.
What is the insertion point of the Gluteus maximus?
Most fibers end in iliotibial tract, which inserts into lateral condyle of tibia; some fibers insert on gluteal tuberosity of femur.
What is the origin of the Pronator teres muscle?
Coronoid process of the ulna.
Which nerves innervate the Levator scapulae muscle?
Dorsal scapular (C5) and cervical (C3, C4) spinal nerves.
What is the innervation of the Gluteus maximus?
Inferior gluteal nerve (L5, S1, S2).
Where does the Pronator teres insert?
Middle of the convexity of the lateral surface of the radius.
What action does the Levator scapulae muscle perform?
Elevates scapula and rotates glenoid cavity inferiorly.
What is the primary action of the Gluteus maximus?
Extends hip joint between flexed and standing positions and assists in its lateral rotation; fixes hip joint and assists in rising from sitting position.
What is the action of the Pronator teres?
Pronates the forearm and flexes the elbow joint.
What is the origin of the Rhomboid minor muscle?
Nuchal ligament; spinous processes of C7 and T1 vertebrae.
What is the origin of the Gluteus medius?
External surface of ilium between anterior and posterior gluteal lines.
What is the origin of the Flexor carpi radialis?
Base of the 2nd (3rd) metacarpal.
What is the origin of the Rhomboid major muscle?
Spinous processes of T2–T5 vertebrae.
What is the insertion point of the Gluteus medius?
Lateral surface of greater trochanter of femur.
What is the action of the Flexor carpi radialis?
Flexes and abducts the hand at the wrist.
What is the insertion point of the Rhomboid minor muscle?
Triangular area at medial end of scapular spine.
What is the action of the Gluteus medius?
Abducts and anterior portions medially rotate hip joint; keeps pelvis level when opposite limb is elevated.
What is the origin of the Palmaris longus?
Medial epicondyle of the humerus.
What is the insertion point of the Rhomboid major muscle?
Medial border of scapula from level of spine to inferior angle.
What is the origin of the Gluteus minimus?
External surface of ilium between anterior and inferior gluteal lines.
What is the action of the Palmaris longus?
Flexes the hand at the wrist and tenses the palmar fascia.
Which nerve innervates the Rhomboid muscles?
Dorsal scapular nerve (C4, C5).
What is the insertion point of the Gluteus minimus?
Anterior surface of greater trochanter of femur.
What is the action of the Gluteus minimus?
Abducts and medially rotates hip joint; keeps pelvis level when opposite limb is elevated.
What actions do the Rhomboid muscles perform?
Retracts scapula and rotates glenoid cavity inferiorly; fix scapula to thoracic wall.
What is the origin of the Tensor fasciae latae?
Anterior superior iliac spine; anterior part of iliac crest.
What is the origin of the Deltoid muscle?
Lateral third of clavicle; acromion and spine of scapula.
What is the insertion point of the Tensor fasciae latae?
Iliotibial tract, which attaches to lateral condyle of tibia (Gerdy tubercle).
What is the insertion point of the Deltoid muscle?
Deltoid tuberosity of humerus.
What is the action of the Tensor fasciae latae?
Flexes hip joint; acts with gluteus maximus to stabilize the extended knee joint.
Which nerve innervates the Deltoid muscle?
Axillary nerve (C5, C6).
What is the origin of the Piriformis?
Anterior surface of 2nd–4th sacral segments; superior margin of greater sciatic notch and sacrotuberous ligament.
What actions does the Deltoid muscle perform?
Clavicular part flexes and medially rotates shoulder joint; acromial part abducts shoulder joint.
What is the insertion point of the Piriformis?
Superior border of greater trochanter of femur.
What is the origin of the Flexor pollicis longus?
Anterior surface of radius and adjacent interosseous membrane.
What is the innervation of the Piriformis?
Branches of anterior rami of S1, S2.
What is the insertion point of the Flexor pollicis longus?
Base of distal phalanx of thumb.
What actions does the Flexor pollicis longus perform?
Flexes wrist joint, carpometacarpal joints, metacarpophalangeal and interphalangeal joints of thumb.
What is the primary action of the Tibialis posterior muscle?
Foot inversion.
What is the origin of the Pronator quadratus?
Distal quarter of anterior surface of ulna.
Where does the Tibialis posterior originate?
Posterior surface of tibia, posterior surface of fibula, and interosseous membrane.
What is the insertion point for the Tibialis posterior?
Tuberosity of navicular bone, all cuneiform bones, cuboid bone, bases of metatarsal bones 2-4.
What is the insertion point of the Pronator quadratus?
Distal quarter of anterior surface of radius.
What is the innervation of the Pronator quadratus?
Anterior interosseous nerve, from median nerve (C8, T1).
