Where Do Muscles Begin and End?

Muscles have an origin (starting point) and an insertion (ending point).

BACK MUSCLES
Extrinsic muscles of the back (Table 2-4-1)
Muscle Origin Insertion Action Innervation
Trapezius Ligamentum nuchae; spines of C7–T12 Lateral clavicle, acromion, spine of scapula, Elevates, retracts, and rotates scapula CN XI, spinal root, spinal nerves C3–C4
Latissimus dorsi Spines of T6–T12, thoracolumbar fascia, iliac crest Intertubercular groove of humerus Extends, adducts, medially rotates humerus Thoracodorsal
Levator scapulae Transverse processes C1–C4 Superior medial border of scapula Elevates scapula Dorsal scapular C3and 4
Rhomboid minor Spines of C7–T1 Inferior medial border of scapula Retracts and rotates scapula Dorsal scapular
Rhomboid major Spines of T2–T5 Inferior medial border of scapula Retracts and rotates scapula Dorsal scapular
Serratus posterior superior Spines of C7–T3 Superior border of ribs 2–5 Elevates ribs Intercostal nerves T2–T5
Serratus posterior inferior Spines of T11–L2 Inferior border of ribs 8–12 Depresses ribs Intercostal nerves T9–T12
Intrinsic muscles of the back (Table 2-4-2)
Muscle Origin Insertion Action Innervation
Superficial layer: splenius
Splenius capitis Ligamentum nuchae Capitis: Mastoid, nuchal line Unilaterally: Laterally flex and rotate head
Splenius cervicis Spinous processes of C7–T3/4 Cervicis: Transverse processes C1–C4 Together: extend head and neck
Intermediate layer: erector spinae
Iliocostalis Sacrum, iliac crests, and lumbar spinous processes Angles of ribs Unilaterally: laterally flex column,
Longissimus T and C transverse processes, mastoid Together: extend vertebral column and head
Spinalis T spinous processes, skull
Deep layer: transversospinalis
Semispinalis Transverse processes C4–T12 Occipital bone, spinous processes 4–6 segments above Extend and rotate column contralaterally
Multifidus Sacrum, ilium, transverse processes T1–T3 Spinous processes 2–4 segments above Stabilise vertebrae during small movements
Rotatores Transverse processes Spinous processes 1–2 segments above Locally extend and rotate vertebral column
Minor deep layer
Interspinales C and L spinous processes Spinous process above Aid in extension of rotation of column
Intertransversarii C and L transverse processes Transverse processes above Aid in lateral flexion of column
Levatores costarum Tips of transverse processes C7–T11 Ribs, between tubercle and angle Elevate ribs, aid in lateral flexion
*Note 1: all of these muscles are supplied by the dorsal rami of the spinal nerves
*Note 2: muscles you should know are those of the erector spinae and transversospinal groups (Adapted from Thompson JC. Netter’s Concise Atlas of Orthopaedic Anatomy. Elsevier Inc., 2006, pp. 25-26)
UPPER LIMB MUSCLES
Scapular muscles* (Table 6-2-2)
Muscle Origin Insertion Action Innervation
Superficial extrinsic muscles
Trapezius Medial third of superior nuchal line, external occipital protuberance, ligamentum nuchae, spinous processes of CVII to TXII Lateral third of posterior clavicle, medial acromion, superior edge of spine of scapula Elevates scapula (descending part), retracts scapula (transverse part), depresses scapula (ascending part); rotates scapula (descending and ascending parts acting together) Spinal root of accessory nerve [XI] and C3, C4
Latissimus dorsi Spinous processes of TVII to TXII, thoracolumbar fascia, iliac crest, lower three to four ribs Floor of intertubercular sulcus of humeru Extends, adducts and medially rotates arm, draws shoulder downwards and backward Thoracodorsal nerve (C6,C7,C8)
Deep extrinsic muscles
Levator scapulae Posterior tubercles of transverse processes CI to CIV Medial border of scapula above base of spine of scapula Elevates scapula medially, inferiorly rotates glenoid cavity Dorsal scapular nerve (C5) and C3 and C4
Rhomboid minor Ligamentum nuchae, spinous processes of CVII and TI Medial border of scapula above base of spine of scapula Retracts and stabilizes the scapula Dorsal scapular nerve (C4,C5)
Rhomboid major Spinous processes of TII–TV Medial border of scapula below base of spine of scapula Retracts and rotates scapula to depress the glenoid cavity Dorsal scapular nerve (C4,C5)
Intrinsic muscles
Deltoid Lateral third of anterior clavicle, lateral acromion, inferior edge of spine of scapula Deltoid tuberosity of humerus Clavicular part –flexes and medially rotates arm; acromial part –abducts arm; spinal part –extends and laterally rotates arm Anterior and posterior branches of axillary nerve (C5,C6)
Supraspinatus Supraspinous fossa of scapula Superior facet of greater tubercle of humerus Initiates arm abduction, acts with rotator cuff muscles Suprascapular nerve (C4,C5,C6)
Infraspinatus Intraspinous fossa of scapula Middle facet of greater tubercle of humerus Lateral rotation of arm (with teres minor) Suprascapular nerve (C5,C6)
Teres minor Upper two thirds of posterior surface of lateral border of scapula Inferior facet of greater tubercle of humerus Lateral rotation of arm, adduction Posterior branch of axillary nerve (C5,C6)
Teres major Posterior surface of inferior angle of scapula Medial lip of intertubercular sulcus Adducts and medially rotates arm Inferior subscapular nerve (C6,C7)
Subscapularis Subscapular fossa Lesser tubercle of humerus Medially rotates arm and adducts it Superior and inferior subscapular nerves (C5,C6,C7)
*main nerve root is indicated in bold
UPPER LIMB MUSCLES
Arm muscles* (Table 6-3-1)
Muscles Origin Insertion Action Innervation
Biceps brachii Long head—supraglenoid tubercle of humerus; Short head: tip of coracoid process of scapula Radial tuberosity, fascia of forearm via bicipital aponeurosis Supinates forearm Flexes forearm when it is supinated Musculocutaneous nerve (C5,C6)
Coracobrachialis Tip of coracoid process of scapula Middle third of medial surface of humerus Flexes and adducts arm Musculocutaneous nerve (C5,C6,C7)
Brachialis Distal half of anterior surface of humerus Coronoid process and tuberosity of ulna Flexes forearm Musculocutaneous nerve (C5,C6)
Triceps brachii Long head—infraglenoid tubercle of scapula; Lateral head —upper half of posterior humerus; Medial head —distal two thirds of medial and posterior humerus Posterior surface of olecranon process of ulna Extends forearm, long head stabilizes head of abducted humerus Radial nerve (C6,C7,C8)
UPPER LIMB MUSCLES
Anterior forearm muscles (Table 6-4-1)
Muscle Origin Insertion Action Innervation
Superficial
Pronator Teres Two heads—medial epicondyle of humerus and coronoid process of ulna Midway along lateral surface of radius Pronates forearm, assists in flexion Median nerve (C6,C7)
Flexor carpi radialis Medial epicondyle of humerus Base of second metacarpal Flexes and abducts hand at wrist Median nerve (C6,C7)
Palmaris longus Medial epicondyle of humerus Distal half of flexor retinaculum and palmar aponeurosis Flexes hand and tenses palmar aponeurosis Median nerve (C7,C8)
Flexor carpi ulnaris Humeral head—medial epicondyle of humerus; Pisiform bone, hook of hamate, base of fifth metacarpal Flexes and adducts hand at wrist Ulnar nerve (C7,C8)
Ulnar head—olecranon and posterior border of ulna
Flexor digitorum superficialis Humeroulnar head—medial epicondyle and coronoid process of ulna Bodies of middle phalanges of medial four digits Flexes middle and proximal phalanges of medial four digits; also flexes hand at wrist Median nerve (C7 to T1)
Radial head—anterior border of radius
Deep
Flexor digitorum profundus Medial and anterior surface of proximal three-quarters of ulna, and interosseous membrane Anterior base of distal phalanges of medial four digits Flexes distal phalanges of medial four digits; assists in flexion of hand at wrist Medial part—ulnar nerve (C8,T1);
Lateral part—medial nerve (C8,T1)
Flexor pollicis longus Anterior surface of radius and interosseous membrane Palmar base of distal phalanx of thumb Flexes phalanges of thumb Anterior interosseous branch of median nerve (C8,T1)
Pronator quadratus Distal fourth of anterior ulna Distal fourth of anterior radius Pronates forearm Anterior interosseous branch of median nerve (C8,T1)
UPPER LIMB MUSCLES
Posterior forearm muscles (Table 6-4-2)
Muscle Origin Insertion Action Innervation
Superficial group
Brachioradialis Proximal two thirds of lateral supracondylar ridge of humerus Lateral side of distal end of radius Flexes forearm Radial nerve (C5 to C7)
Extensor carpi radialis longus Distal one-third of lateral supracondylar ridge of humerus Dorsal base of second metacarpal Extends and abducts hand at wrist Radial nerve (C6,C7)
Extensor carpi radialis brevis Lateral epicondyle of humerus (common extensor tendon) Dorsal base of third metacarpal Extends and abducts hand at wrist Deep branch of radial nerve (C7,C8)
Extensor digitorum Lateral epicondyle of humerus (common extensor tendon) Extensor expansions of medial four digits Extends medial four digits; assists in wrist extension Posterior interosseous nerve (C7,C8)
Extensor digiti minimi Lateral epicondyle of humerus (common extensor tendon) Extensor expansion of fifth digit Extends fifth digit Posterior interosseous nerve (C7,C8)
Extensor carpi ulnaris Lateral epicondyle of humerus and posterior border of ulna (common extensor tendon) Dorsal base of fifth metacarpal Extends and abducts hand at wrist Posterior interosseous nerve (C7,C8)
Anconeus Posterior surface of lateral epicondyle of humerus Lateral surface of olecranon and posterior proximal ulna Assists triceps brachii in extending forearm Radial nerve (C7 to T1)
Deep group
Supinator Lateral epicondyle of humerus, supinator crest Lateral, posterior and anterior surfaces of proximal third of radius Supinates forearm Deep branch of radial nerve (C5,C6)
Abductor pollicis longus Posterior surface of ulna, radius, and interosseous membrane Base of first metacarpal Abducts and extends thumb Posterior interosseous nerve (C7,C8)
Extensor pollicis brevis Posterior surface of radius and interosseous membrane Base of proximal phalanx of thumb Extends proximal phalanx of thumb Posterior interosseous nerve (C7,C8)
Extensor pollicis longus Posterior surface of middle third of ulna and interosseous membrane Base of distal phalanx of thumb Extends distal phalanx of thumb Posterior interosseous nerve (C7,C8)
Extensor indicis Posterior surface of ulna and interosseous membrane Extensor expansion of second digit Extends second digit Posterior interosseous nerve (C7,C8)
UPPER LIMB MUSCLES
Intrinsic Hand Muscles (Table 6-5-1)
Muscle Origin Insertion Action Innervation
Abductor pollicis brevis** Flexor retinaculum, tubercles of scaphoid and trapezium Lateral side of base of proximal phalanx of thumb (1st digit) Abducts and assists in opposition of thumb Recurrent branch of median nerve (C8,T1)
Flexor pollicis brevis** Flexor retinaculum and trapezium Lateral side of base of proximal phalanx of thumb Flexes proximal phalanx of thumb Recurrent branch of median nerve (C8,T1)
Opponens pollicis** Flexor retinaculum and trapezium Lateral side of 1st metacarpal Draws 1st metacarpal forward and rotates it medially Recurrent branch of median nerve (C8,T1)
Adductor pollicis Oblique head—bases of second and third metacarpals capitate and adjacent bones; Transverse head—anterior surface of third metacarpal Medial side of base of proximal phalanx of thumb Adducts thumb Deep branch of ulnar nerve (C8,T1)
Palmaris brevis Palmar aponeurosis Skin of ulnar border of palm Deepens the hollow of the hand Superficial palmar branch of ulnar nerve (C8)
Abductor digiti minimi* (hand) Pisiform bone, tendon of flexor carpi ulnaris Medial side of base of proximal phalanx of little finger Abducts the little finger (fifth digit) Deep branch of ulnar nerve (C8,T1)
Flexor digiti minimi brevis* (hand) Flexor retinaculum and hook of hamate bone Medial side of base of proximal phalanx of little finger Flexes proximal phalanx of the little finger Deep branch of ulnar nerve (C8,T1)
Opponens digiti minimi* Flexor retinaculum and hook of hamate bone Medial side of fifth metacarpal Draws fifth metacarpal anteriorly and rotates it to face thumb Deep branch of ulnar nerve (C8,T1)
Lumbricals 1 and 2 Lateral two tendons of flexor digitorum profundus Lateral sides of extensor expansion of digits 2 and 3 Extends digits at interphalangeal joints and flexes metacarpophalangeal joints Median nerve (C8,T1)
Lumbricals 3 and 4 Medial three tendons of flexor digitorum profundus Lateral sides of extensor expansion of digits 4 and 5 Extends digits at interphalangeal joints and flexes metacarpophalangeal joints Deep branch of ulnar nerve (C8, T1)
Dorsal interossei 1–4† Adjacent sides of two metacarpal bones Base of proximal phalanx and extensor expansion of digits 2–4 Abducts digits from axial line of hand—third digit Deep branch of ulnar nerve (C8,T1)
Palmar interossei 1–4‡ Palmar surfaces of metacarpals 2, 4, and 5 Bases of proximal phalanx and extensor expansion of digits 2, 4, and 5 Adducts digits toward axial line of hand—third digit Deep branch of ulnar nerve (C8,T1)
*Muscles located in the hypothenar compartment of the hand
**Muscles located in the thenar compartment of the hand
†Bipennate muscles
‡Unipennate muscles: remembering DAB (Dorsal interossei ABduct) and PAD (Palmar interossei ADduct) can help you figure out where these muscles insert
LOWER LIMB MUSCLES
Muscles of the Gluteal Region (Table 7-2-2)
Muscle Origin Insertion Action Innervation
Gluteus maximus Ilium posterior to posterior gluteal line dorsal sacrum, sacrotuberous ligament Iliotibial tract of fascia lata, gluteal tuberosity of femur Extends thigh, assists lateral rotation Inferior gluteal nerve (L5 to S2)
Gluteus medius Lateral surface of ilium between anterior and posterior gluteal lines Lateral surface of greater trochanter of femur Abducts thigh, rotates thigh medially Superior gluteal nerve (L4 to S1)
Gluteus minimus Lateral surface of ilium between anterior and inferior gluteal lines Anterior border of greater trochanter of femur Abducts thigh, rotates thigh medially Superior gluteal nerve (L4 to S1)
Piriformis Anterior surface of sacrum and sacrotuberous ligament Superior border of greater trochanter of femur Laterally rotates thigh, abducts flexed thigh Ventral rami of S1 and S2
Obturator internus Pelvic surface of obturator membrane and margins of obturator foramen Medial surface of greater trochanter of femur Laterally rotates thigh, abducts flexed thigh Nerve to obturator internus (L5 to S2)
Gemellus superior Outer surface of ischial spine Medial surface of greater trochanter of femur Laterally rotates thigh Nerve to obturator internus (L5 to S2)
Gemellus inferior Upper margin of ischial tuberosity Medial surface of greater trochanter of femur Laterally rotates thigh Nerve to quadratus femoris (L4 to S1)
Quadratus femoris Lateral margin of ischial tuberosity Quadrate tubercle on intertrochanteric crest of femur Laterally rotates thigh Nerve to quadratus femoris (L4 to S1)
LOWER LIMB MUSCLES
Anterior Thigh Muscles (Table 7-2-3)
Muscle Origin Insertion Action Innervation
Iliopsoas/ psoas major Sides of vertebra T12 to L5 and transverse processes of L1–L5 Lesser trochanter of femur Flexes thigh at hip and stabilizes the hip Ventral rami of lumbar spinal nerves 1–3
Iliacus Iliac crest, iliac fossa, ala of scrum, and anterior sacroiliac ligaments Tendon of psoas major and body of femur, inferior to lesser trochanter Flexes thigh at hip and stabilizes the hip Femoral nerve (L2–L3)
Tensor fasciae latae Anterior superior iliac spine and anterior part of external lip of iliac crest Iliotibial tract → lateral condyle of tibia Abducts, medially rotates and flexes the thigh, stabilizes trunk on thigh Superior gluteal nerve (L4–L5)
Sartorius ASIS and superior part of notch below it Superior part of medial surface of tibia Abducts, medially rotates and flexes the thigh Femoral nerve (L2–L3)
Quadriceps femoris
Rectus femoris Anterior inferior iliac spine and groove superior to acetabulum Base of patella and to tibial tuberosity via patellar ligament Extends the leg at the knee joint and flexes the thigh at the hip joint Femoral nerve (L2–L4)
Vastus lateralis Greater trochanter and lateral lip of linea aspera of femur Base of patella and to tibial tuberosity via patellar ligament Extends the leg at the knee joint Femoral nerve (L2–L4)
Vastus medialis Intertrochanteric line and medial lip of linea aspera of femur Base of patella and to tibial tuberosity via patellar ligament Extends the leg at the knee joint Femoral nerve (L2–L4)
Vastus intermedius Anterior and lateral surfaces of body of femur Base of patella and to tibial tuberosity via patellar ligament Extends the leg at the knee joint Femoral nerve (L2–L4)
LOWER LIMB MUSCLES
Medial Thigh Muscles (Table 7-2-4)
Muscle Origin Insertion Action Innervation
Pectineus Pecten pubis Pectineal line of femur Adducts and flexes thigh Femoral nerve (L2–L3) and sometimes obturator nerve
Adductor longus Body of pubis, inferior to pubic crest Middle third of linea aspera of femur Adducts thigh Obturator nerve (anterior division) (L2–L4)
Adductor brevis Body and inferior pubic ramus Pectineal line and proximal part of linea aspera of femur Adducts and flexes thigh Obturator nerve (L2 to L4)
Adductor magnus Inferior pubis ramus, ramus of ischium, Hamstring part: ischial tuberosity Gluteal tuberosity, linea aspera, supracondylar lineHamstring part: adductor tubercle Adducts and flexes thigh (adductor part)Extends thigh (hamstring part) Adductor part: obturator nerve (L2–L4) Hamstring part: tibial nerve (L4)
Gracilis Body of pubis and inferior pubic ramus Superior part of medial surface of tibia Adducts thigh, flexes and medially rotates the leg Obturator nerve (L2–L3)
Obturator externus Margins of obturator foramen and obturator membrane Trochanteric fossa of femur Laterally rotates the thigh and stabilizes head of femur in acetabulum Obturator nerve (L2–L3)
Posterior Thigh Muscles (Table 7-2-5)
Muscle Origin Insertion Action Innervation
Semitendinosus Upper and medial ischial tuberosity Superior part of medial surface of tibia Flexes leg, extends thigh Tibial division of sciatic nerve (L5 to S2)
Semimembranosus Upper and lateral ischial tuberosity Posterior part of medial condyle of tibia Flexes leg, extends thigh Tibial division of sciatic nerve (L5 to S2)
Biceps femoris Long head—ischial tuberosity Lateral side of head of fibula Flexes and laterally rotates leg, extends thigh Long head—tibial division of sciatic nerve (L5 to S2)
Short head—lateral lip of linea aspera, lateral supracondylar line of femur Short head—common fibular division of sciatic nerve (L5 to S2)
LOWER LIMB MUSCLES
Muscles of the anterolateral leg (Table 7-4-1)
Muscle Origin Insertion Action Innervation
Anterior Muscles
Tibialis anterior Lateral condyle and proximal half of lateral tibia, interosseous membrane Medial plantar surfaces of medial cuneiform and base of first metatarsal Dorsiflexes ankle and inverts foot Deep fibular nerve (L4,L5)
Extensor hallucis Middle half of anterior surface of fibula and interosseous membrane Base of distal phalanx of great toe Extends great toe and dorsiflexes ankle Deep fibular nerve (L5,S1)
Extensor digitorum longus Lateral condyle of tibia and proximal three quarters of anterior surface of interosseous membrane Middle and distal phalanges of second through fifth toes Extends second through fifth toes and dorsiflexes ankle Deep fibular nerve (L5,S1)
Fibularis tertius Distal third of anterior surface of fibula and interosseous membrane Dorsum of base of fifth metatarsal Dorsiflexes ankle and aids in eversion of foot Deep fibular nerve (L5,S1)
Lateral Muscles
Fibularis longus Head and proximal two thirds of lateral fibula Plantar base of first metatarsal and medial cuneiform Everts foot and weakly plantarflexes ankle Superficial fibular nerve (L5 to S2)
Fibularis brevis Distal two thirds of lateral surface of fibula Dorsal surface of tuberosity on base of fifth metatarsal Everts foot and weakly plantarflexes ankle Superficial fibular nerve (L5 to S2)
LOWER LIMB MUSCLES
Muscles of the Posterior Leg (Table 7-4-2)
Muscle Origin Insertion Action Innervation
Superficial Muscles
Gastrocnemius Lateral head—lateral aspect of lateral condyle of femur. Posterior aspect of calcaneus via the calcaneal tendon Plantarflexes the ankle joint, assists in flexion of the knee joint Tibial nerve (S1,S2)
Medial head—popliteal surface above medial condyle of femur
Soleus Posterior aspect of head of fibula, proximal fourth of posterior surface of fibula, soleal line of tibia Posterior aspect of calcaneus via the calcaneal tendon Plantarflexes the ankle and stabilizes the leg over the foot Tibial nerve (S1,S2)
Plantaris Popliteal surface of femur Calcaneal tendon Weakly assists gastrocnemius Tibial nerve (L5,S1)
Deep Muscles
Popliteus Lateral aspect of lateral condyle of femur and lateral meniscus Posterior tibia above soleal line Unlocks and weakly flexes knee joint Tibial nerve (L4 to S1)
Flexor hallucis longus Distal two-thirds of posterior fibula and inferior part of interosseous membrane Base of distal phalanx of great toe (hallux) Flexes great toes, weakly plantarflexes the ankle Tibial nerve (L5 to S2)
Flexor digitorum longus Medial part of posterior tibia inferior to soleal line Plantar bases of distal phalanges of lateral four toes Flexes lateral four toes, plantarflexes ankle Tibial nerve (L5,S1)
Tibialis posterior Posterior tibia below soleal line, interosseous membrane, proximal half of posterior fibula Tuberosity of navicular bone, all cuneiforms, cuboid and bases of second through fourth metatarsals Plantarflexes the ankle and inverts the foot Tibial nerve (L5S1)
LOWER LIMB MUSCLES
Layers of plantar foot (Table 7-5-1)
Muscle Proximal Attachment Distal Attachment Action Innervation
First Layer—deep to plantar aponeurosis
Abductor hallucis Medial process of calcaneal tuberosity Medial side, base of proximal phalanx of first toe Abducts and flexes first toe Medial plantar nerve
Flexor digitorum brevis Medial process of calcaneal tuberosity Four tendons split to allow passage of long flexor tendons, insert on middle phalanges Flexes second through fifth toes Medial plantar nerve
Abductor digiti minimi Calcaneus Lateral side, proximal phalanx of fifth toe Abducts and flexes fifth toe Lateral plantar nerve
Neurovascular Plane: Medial and lateral plantar nerves
Medial and lateral plantar arteries and nerves
Second Layer
Quadratus plantae Medial and lateral sides of plantar surface of calcaneus Lateral edge of flexor digitorum longus tendon Corrects for oblique pull of FDL tendon; thus assists in flexion of toes Lateral plantar nerve
Lumbricals First: Medial side of tendon to second toe Medial side of dorsal digital expansions Flex proximal phalanges at MP joint, extend distal phalanges at PIP and DIP joints First (medial): Medial plantar nerve
Second through fourth: Adjacent sides of contiguous tendons Second through fourth: Lateral plantar nerve
Also: Tendon → tendons of flexor digitorum longus, tendon of flexor hallucis longus
Third Layer
Flexor hallucis brevis Plantar surfaces of cuboid and lateral cuneiform Divides in two, to each side of base of proximal phalanx of first toe Flexes proximal phalanx of first toe Medial plantar nerve
Adductor hallucis Oblique head: bases of second through fourth metatarsals Lateral side, base of proximal phalanx of first toe (both heads) Adducts first toe, maintains transverse arch Deep branch of lateral plantar nerve
Transverse head: Ligaments of metatarsophalangeal joints
Flexor digiti minimi brevis Base of fifth metatarsal Base of proximal phalanx of fifth toe Flexes proximal phalanx of fifth toe Superficial branch, lateral plantar nerve
Neurovascular plane: Deep branches of lateral plantar nerve and artery; plantar arterial arch from lateral plantar artery
Fourth Layer
Plantar interossei (3) Bases and medial sides of third through fifth metatarsals Medial sides of bases of proximal phalanges of third through fifth toes Adduct second through fourth toes and flex MP joint Lateral plantar nerve
Dorsal interossei(4) Adjacent sides of first through fifth metatarsals First: medial side of proximal phalanx of second toe Abduct second through fourth toes and flex MP joints Lateral plantar nerve
Second through fourth: lateral sides of second through forth toes