Unit 3 Flashcards
Tibialis Anterior Origin
Lateral condyle and superior 2/3 of lateral surface of tibia and interosseous membrane
Tibialis Anterior Insertion
Medial and inferior surfaces of medial cuneiform and base of 1st metatarsal
Tibialis Anterior Innervation
Deep fibular nerve (L4, L5)
Tibialis Anterior Action
Dorsiflexes ankle; inverts foot; supports medial longitudinal arch of foot
Extensor hallucis longus Origin
Middle part of anterior surface of fibula and interosseous membrane
Extensor hallucis longus Insertion
Dorsal aspect of base of distal phalanx of great toe (hallux)
Extensor hallucis longus Innervation
Deep fibular nerve (L5, S1)
Extensor hallucis longus Action
Extends great toe; dorsiflexes ankle
Extensor digitorum longus Origin
Lateral condyle of tibia and superior 2/3 of anterior surface of fibula and interosseous membrane
Extensor digitorum longus Insertion
Middle and distal phalanges of lateral four digits
Extensor digitorum longus Innervation
Deep fibular nerve (L5, S1)
Extensor digitorum longus Action
Extends lateral four digits; dorsiflexes ankle
Fibularis Tertius Origin
Inferior third of anterior surface of fibula and interosseous membrane
Fibularis Tertius Insertion
Dorsum of base of 5th metatarsal
Fibularis Tertius Innervation
Deep fibular nerve (L5, S1)
Fibularis Tertius Action
Dorsiflexes ankle; aids in eversion of foot
Fibularis Longus Origin
Head and superior two thirds of lateral surface of fibula
Fibularis Longus Insertion
Base of 1st metatarsal and medial cuneiform
Fibularis Longus Innervation
Superficial fibular nerve (L5, S1, S2)
Fibularis Longus Action
Evert foot; weakly plantarflex ankle, supports transverse arch of foot
Fibularis Brevis Origin
Middle part of lateral surface of fibula
Fibularis Brevis Insertion
Dorsal surface of tuberosity of base of 5th metatarsal
Fibularis Brevis Innervation
Superficial fibular nerve (L5, S1, S2)
Fibularis Brevis Action
Evert foot; weakly plantarflex foot
Extensor Digitorum Brevis Origin
Calcaneus (dorsal surface)
Extensor Digitorum Brevis Insertion
2nd to 4th toes (at dorsal aponeuroses and bases of the middle phalanges)
Extensor Digitorum Brevis Innervation
Deep fibular nerve (L5, S1)
Extensor Digitorum Brevis Action
Extension of the metatarsalphalangeal and proximal interphalangeal joints of the 2nd to 4th toes
Extensor Hallucis Brevis Origin
Calcaneus (dorsal surface)
Extensor Hallucis Brevis Insertion
1st toe (at dorsal aponeurosis and proximal phalanx)
Extensor Hallucis Brevis Innervation
Deep fibular nerve (L5, S1)
Extensor Hallucis Brevis Action
Extension of the metatarsalphalangeal joint of the 1st toe
Gastrocnemius Origin
Lateral head: lateral aspect of lateral condyle of femur
Medial head: popliteal surface of femur, superior to medial condyle
Gastrocnemius Insertion
Posterior surface of calcaneus via calcaneal tendon
Gastrocnemius Innervation
Tibial nerve (S1, S2)
Gastrocnemius Action
Plantarflexes ankle when knee is extended; raises heel during walking; flexes knee joint
Soleus Origin
Posterior aspect of head of fibula, superior quarter of posterior surface of fibula, soleal line, and medial border of tibia
Soleus Insertion
Posterior surface of calcaneus via calcaneal tendon
Soleus Innervation
Tibial nerve (S1, S2)
Soleus Action
Plantarflexes ankle; steadies leg on foot
Plantaris Origin
Inferior end of lateral supracondylar line of femur and oblique popliteal ligament
Plantaris Insertion
Calcaneal tuberosity
Plantaris Action
Weakly assists gastrocnemius in plantarflexing ankle; function is probably mainly proprioceptive
Popliteus Origin
Lateral surface of lateral condyle of femur and lateral meniscus
Popliteus Insertion
Posterior surface of tibia, superior to soleal line
Popliteus Innervation
Tibial nerve (L4, L5, S1)
Popliteus Action
Weakly flexes knee and unlocks it by laterally rotating femur on fixed tibia, may also medially rotate tibia of unplanted limb
Flexor Hallucis Longus Origin
Inferior two thirds of posterior surface of fibula and ifnerior part of interosseous membrane
Flexor Hallucis Longus Insertion
Base of distal phalanx of great toe (hallux)
Flexor Hallucis Longus Innervation
Tibial nerve (S2, S3)
Flexor Hallucis Longus Action
Flexes great toe at all joints; weakly plantarflexes ankle; supports medial longitudinal arch of foot
Flexor Digitorum Longus Origin
Medial part of posterior surface of tibia inferior to soleal line and by a broad tendon to fibula
Flexor Digitorum Longus Insertion
Bases of distal phalanges of lateral four digits
Flexor Digitorum Longus Innervation
Tibial nerve (S2, S3)
Flexor Digitorum Longus Action
Flexes lateral four digits; plantarflexes ankle; supports longitudinal arches of foot
Tibialis Posterior Origin
Interosseous membrane, posterior surface of tibia inferior to soleal line, and posterior surface of fibula
Tibialis Posterior Insertion
Primarily to tuberosity of navicular; also to cuneiforms, cuboid, and bases of 2nd-4th metatarsals
Tibialis Posterior Innervation
Tibial nerve (L4, L5)
Tibialis Posterior Action
Plantarflexes ankle; inverts foot; supports medial longitudinal arch of foot
Abductor Hallucis Origin
Medial tubercle of tuberosity of calcaneus, flexor retinaculum, and plantar aponeurosis
Abductor Hallucis Insertion
Medial side of base of proximal phalanx of 1st digit
Abductor Hallucis Innervation
Medial plantar nerve (S2, S3)
Abductor Hallucis Action
Abducts and flexes 1st digit (great toe, hallux)
Flexor Digitorum Brevis Origin
Medial tubercle of tuberosity of calcaneus, plantar aponeurosis, and intermuscular septa
Flexor Digitorum Brevis Insertion
Both sides of middle phalanges of lateral four digits
Flexor Digitorum Brevis Innervation
Medial plantar nerve (S2, S3)
Flexor Digitorum Brevis Action
Flexes lateral four digits
Abductor Digiti Minimi Origin
Medial and lateral tubercles of tuberosity of calcaneus, plantar aponeurosis, and intermuscular septa
Abductor Digiti Minimi Insertion
Lateral side of base of proximal phalanx of 5th digit
Abductor Digiti Minimi Innervation
Lateral plantar nerve (S2, S3)
Abductor Digiti Minimi Action
Abducts and flexes 5th digit
Quadratus Plantae Origin
Medial surface and lateral margin of plantar surface of calcaneus
Quadratus Plantae Insertion
Posterolateral margin of tendon of flexor digitorum longus
Quadratus Plantae Innervation
Lateral plantar nerve (S2, S3)
Quadratus Plantae Action
Assists flexor digitorum longus in flexing lateral four digits
Lumbricals Origin
Tendons of flexor digitorum longus
Lumbricals Insertion
Medial aspect of expansion over lateral four digits
Lumbricals Innervation
Medial one: medial plantar nerve (S2, S3)
Lateral three: lateral plantar nerve (S2, S3)
Lumbricals Action
Flex proximal phalanges; extend middle and distal phalanges of lateral four digits
Flexor Hallucis Brevis Origin
Plantar surfaces of cuboid and lateral cuneiform
Flexor Hallucis Brevis Insertion
Both sides of base of proximal phalanx of 1st digit
Flexor Hallucis Brevis Innervation
Medial plantar nerve (S2, S3)
Flexor Hallucis Brevis Action
Flexes proximal phalanx of 1st digit
Adductor Hallucis Origin
Oblique head: bases of 2nd-4th metatarsals
Transverse head: plantar ligaments of 3rd-5th metatarsophalangeal joints
Adductor Hallucis Insertion
Lateral side of base of proximal phalanx of 1st digit
Adductor Hallucis Innervation
Deep branch of lateral plantar nerve (S2, S3)
Adductor Hallucis Action
Adducts first digit; assists in maintaining transverse arch of foot
Flexor Digiti Minimi Brevis Origin
Base of 5th metatarsal
Flexor Digiti Minimi Brevis Insertion
Base of proximal phalanx of 5th digit
Flexor Digiti Minimi Brevis Innervation
Superficial branch of lateral plantar nerve (S2, S3)
Flexor Digiti Minimi Brevis Action
Flexes proximal phalanx of 5th digit
Plantar interossei (three muscles) Origin
Bases and medial sides of metatarsals 3-5
Plantar interossei (three muscles) Insertion
Medial sides of bases of proximal phalanges of 3rd-5th digits
Plantar interossei (three muscles) Innervation
Lateral plantar nerve (S2, S3)
Plantar interossei (three muscles) Action
Adduct digits 3-5, flex metatarsophalangeal joints
Dorsal interossei (four muscles) Origin
Adjacent sides of metatarsals 1-5
Dorsal interossei (four muscles) Insertion
First: medial side of base of proximal phalanx of 2nd digit
Second to fourth: lateral sides of 2nd to 4th digits
Dorsal interossei (four muscles) Innervation
Lateral plantar nerve (S2, S3)
Dorsal interossei (four muscles) Action
Abduct digits (2-4), flex metatarsophalangeal joints
Sternocleidomastoid Origin
Sternal head: anterior surface of manubrium of sternum
Clavicular head: superior surface of medial third of clavicle
Sternocleidomastoid Insertion
Lateral surface of mastoid process of temporal bone and lateral half of superior nuchal line
Sternocleidomastoid Innervation
Spinal accessory nerve (CN XI), C2, C3
Sternocleidomastoid Action
Unilateral contraction: titls head to same side and rotates it so face is turned superiorly toward opposite side
Bilateral contraction: extend neck at atlanto-occipital joint; flexes cervical vertebrae so that chin approaches manubrium; extends superior cervical vertebrae while flexing inferior vertebrae so chin is thrust forward with head kept level
Trapezius Origin
Medial third of superior nuchal line, external occipital protuberance, nuchal ligament, spinous processes of C7-T12 vertebrae
Trapezius Insertion
Lateral third of clavicle, acromion, spine of scapula
Trapezius Innervation
Spinal accessory nerve (CN XI), C3, C4
Trapezius Action
Descending: Elevate scapula
Middle: Retract scapula
Ascending: Depress scapula
Platysma Origin
Fascia covering superior parts of pectoralis major and deltoid muscles
Platysma Insertion
Inferior border of mandible, skin, and subcutaneous tissues of lower face
Platysma Innervation
Cervical branch of facial nerve (CN VII)
Platysma Action
Draws corners of mouth inferiorly and widens it as in expressions of sadness and fright
Mylohyoid Origin
Mylohyoid line of mandible
Mylohyoid Insertion
Mylohyoid raphe and body of hyoid
Mylohyoid Innervation
Nerve to mylohyoid; a branch of inferior alveolar nerve (from mandibular nerve, CN V3)
Mylohyoid Action
Elevates hyoid, floor of mouth, and tongue during swallowing and speaking
Geniohyoid Origin
Inferior mental spine of mandible
Geniohyoid Insertion
Body of hyoid
Geniohyoid Innervation
C1 via hypoglossal nerve (CN XII)
Geniohyoid Action
Pulls hyoid anterosuperiorly; shortens floor of mouth; widens pharynx
Stylohyoid Origin
Styloid process of temporal bone
Stylohyoid Insertion
Body of hyoid
Stylohyoid Innervation
Stylohyoid branch of facial nerve (CN VII)
Stylohyoid Action
Elevates and retracts hyoid, thus elongating floor of mouth
Digastric Origin
Anterior belly: digastric fossa of mandible
Posterior belly: mastoid notch of temporal bone
Digastric Insertion
Intermediate tendon to body and greater horn of hyoid
Digastric Innervation
Anterior belly: nerve to mylohyoid, a branch of inferior alveolar nerve
Posterior belly: digastric branch of facial nerve (CN VII)
Digastric Action
Working with infrahyoid muscles, depresses mandible against resistance elevates and steadies hyoid during swallowing and speaking
Sternohyoid Origin
Manubrium of sternum and medial end of clavicle
Sternohyoid Insertion
Body of hyoid
Sternohyoid Innervation
C1-C3 by a branch of ansa cervicalis
Sternohyoid Action
Depresses hyoid after elevation during swallowing
Omohyoid Origin
Superior border of scapula near suprascapular notch
Omohyoid Insertion
Inferior border of hyoid
Omohyoid Innervation
C1-C3 by a branch of ansa cervicalis
Omohyoid Action
Depresses, retracts, and steadies hyoid
Sternothyroid Origin
Posterior surface of manubrium of sternum
Sternothyroid Insertion
Oblique line of thyroid cartilage
Sternothyroid Innervation
C2 and C3 by a branch of ansa cervicalis
Sternothyroid Action
Depresses hyoid and larynx
Thyrohyoid Origin
Oblique line of thyroid cartilage
Thyrohyoid Insertion
Inferior border of body and greater horn of hyoid
Thyrohyoid Innervation
C1 via hypoglossal nerve
Thyrohyoid Action
Depresses hyoid and elevates larynx
Temporalis Origin
Floor of temporal fossa and deep surface of temporalis fascia
Temporalis Insertion
Tip and medial surface of coronoid process and anterior border of ramus of mandible
Temporalis Innervation
Anterior trunk of mandibular nerve (CN V3) via deep temporal nerve
Temporalis Action
Elevates mandible; closing jaw, retracts mandible
Masseter Origin
Inferior border and medial surface of maxillary process of zygomatic bone and zygomati arch
Masseter Insertion
Angle and lateral surface of ramus of mandible
Masseter Innervation
Mandibular nerve (CN V3) via masseteric nerve
Masseter Action
Elevates mandible
Lateral Pterygoid Origin
Infratemporal surface and greater wing of sphenoid and lateral surface of lateral pterygoid plate
Lateral Pterygoid Insertion
Joint capsule and articular disc of TMJ; pterygoid fovea on anteromedial aspect of neck of condyloid process of mandible
Lateral Pterygoid Innervation
Mandibular nerve (CN V3) via nerves to lateral pterygoid
Medial Pterygoid Origin
Medial surface of lateral pterygoid plate and pyramidal process of palantine bone and tuberoisty of maxilla
Medial Pterygoid Insertion
Medial surface of ramus of mandible, inferior to mandibular foramen
Medial Pterygoid Innervation
Mandibular nerve (CN V3) via nerve to medial pterygoid
Medial Pterygoid Action
Elevates mandible; protrudes mandible
Lateral Pterygoid Action
Acting bilaterally: protracts mandible and depresses chin
Acting unilaterally: swings jaw toward contralateral side