Lower Ex. Muscles
Extrinsic (Ventral Rami)
Superficial (axioappendicular) (limb movement)
Latissimus dorsi (C6-8)
attachments- from lower thoracic spinous processes, thoracolumbar fascia & iliac crest to the floor of the intertubercular sulcus of the humerus
actions- (HANDCUFF MUSCLES) adduction, extension & medial rotation of humerus
innervation- thoracodorsal nerve
Levator scapulae (C4-5)
attachments- from transverse processes of C1-C4 to the superior angle & superomedial border of the scapula
actions- elevation & downward rotation of the scapula
innervation- dorsal scapular nerve (sensory: direct branches of C3-4)
Trapezius (Accessory n. [CN XI] motor; C3-4 sensory)
attachments- from the superior nuchal line, external occipital protuberance, ligamentum nuchae, & cervical & thoracic spinous processes to the clavicle, acromion & scapular spine
actions- scapular elevation (upper), depression (lower), retraction (middle) & upward rotation (upper & lower)
innervation- accessory nerve (CN XI; motor) & C3-4 (sensory)
Intermediate (respiratory)
Serratus posterior superior
attachments- from spinous processes of C7-T3 to inferior borders of ribs 2-5
function- proprioception of thoracic wall
innervation- intercostal nn. (T1-4)
Serratus posterior inferior
attachments- from spinous processes of T11-L2 to inferior borders of ribs 9-12
function- proprioception of thoracic wall
innervation- intercostal nn. (T9-12)
Intrinsic (Dorsal Rami)
Superficial
Splenius capitis (attached to skull)
attachments: from ligamentum nuchae and spinous processes T4-C7 to the mastoid process
actions: extension, lateral flexion, ipsilateral rotation
innervation: dorsal rami of spinal nerves
Splenius cervicis (attached to neck)
attachments: from spinous processes of T3-T6 to posterior tubercles of transverse processes of C1-3
actions: extension, lateral flexion, ipsilateral rotation
innervation: dorsal rami of spinal nerves
Int
Erector spinae
attachments- from TLF (Thoracolumbar fascia) attached to the sacrum, iliac crest, spinous processes L5-T11, supraspinous lig., angles of ribs to costal angles (iliocostalis), ribs & transverse processes (longissimus), and spinous processes (spinalis)
Spinalis: thoracis, cervicis, capitis (represented as semispinalis capitis)
Longissimus: capitis, cervicis, thoracis
Iliocostalis: cervicis, thoracis, lumborum
Action: Extension and lateral flexion of vertebral column
Deep
Transversospinales
Semispinalis
attachments- from transverse processes to distant superior spinous processes
1. Semispinalis: capitis, cervicis, thoracis
actions- extension & contralateral rotation of the vertebral column
Multifidus
attachments- from sacrum, posterior SI ligament, posterior iliac spine, transverse processes to more superior spinous processes
multifidus: sacral, lumbar, thoracic, cervical
actions- extension & contralateral rotation of the vertebral column
Rotatores longus and brevis (transversospinales group)
attachments: transverse to spinous process of vertebra above (1-2 levels)
actions: extension & contralateral rotation of the vertebral column
Interspinales
attachments: between spinous processes of adjacent vertebrae cervical (6), thoracic (2-3), lumbar (4)
action: extension of spine
Intertransversarii
attachments: between the transverse processes of adjacent vertebrae
action: lateral flexion of spine
4&5 Name the attachments, innervation, and actions of the muscles on the Structure Information List
Anterior Femoral Muscles (segmental innervation)
Iliopsoas (L1-4), a combination of the following two muscles:
1. Iliacus (L2-3-4)
attachments- from iliac fossa, iliac crest, sacral ala & sacroiliac ligaments to lesser trochanter of femur
actions- flexes and stabilizes the hip joint
innervation- femoral nerve
2. Psoas major (L. muscle of the loin) (L1-2-3-4)
attachments- from anterior transverse processes, vertebral bodies & discs (T12-L5) to the lesser trochanter of femur
actions- flexes and stabilizes the hip joint
innervation- ventral rami L1-4 (from lumbar plexus)
Rectus femoris (L2, 3, 4) (L. straight)
attachments- from anterior inferior iliac spine and groove superior to the acetabulum to the base of the patella
actions- flexes hip, and extends knee
innervation- femoral nerve
Sartorius (L. sartor, a tailor) (L2-3)
attachments- from anterior superior iliac spine to the medial aspect of the proximal tibia
actions- flexes, abducts & laterally rotates hip, and flexes & assists medial rotation of the knee
innervation- femoral nerve
Tensor fasciae latae (L4-5-S1)
attachments- from anterior superior iliac spine & external lip iliac crest to iliotibial tract
actions- abducts, flexes & medially rotates hip, and assists in maintaining knee extension
innervation- superior gluteal nerve
Vastus intermedius (L2, 3, 4)
attachments- from the anterior aspect of the proximal 2/3rds of the femoral shaft to the lateral border of the patella
actions- extends knee
innervation- femoral nerve
Vastus lateralis (L2, 3, 4)
attachments- from the intertrochanteric line, greater trochanter, gluteal tuberosity & linea aspera to the base & lateral border of the patella
actions- extends knee
innervation- femoral nerve
Vastus medialis (L2, 3, 4)
attachments- from the intertrochanteric line, spiral line, linea aspera & medial supracondylar line to the base & medial border of the patella
actions- extends leg
innervation- femoral nerve
Articularis genu (L2, 3, 4; small muscle that may be blended with vastus intermedius)
attachments- from the distal anterior shaft of femur to proximal portion of synovial membrane of knee joint
actions- pulls articular capsule proximally
innervation- femoral nerve (a branch of the nerve from the vastus intermedius)
Medial Femoral Muscles
Adductor brevis (L2-3-4)
attachments- from inferior pubic ramus to distal 2/3 pectineal line and medial lip linea aspera
actions- adducts and flexes hip
innervation- obturator nerve
Adductor longus (L2-3-4)
attachments- from pubic crest to medial lip linea aspera
actions- adducts, medially rotates, and flexes hip
innervation- obturator nerve
Adductor magnus (adductor part: L2-3-4 & hamstrings part: L4-5-S1)
attachments- from the inferior pubic ramus, ischial ramus & tuberosity to gluteal tuberosity, linea aspera (adductor part), medial supracondylar ridge & adductor tubercle of the femur (hamstring part)
actions- adducts, flexes (adductor part) & extends (hamstring part) hip
innervation- obturator nerve (adductor part) & tibial division of the sciatic nerve (hamstring part)
Gracilis (L. scanty) (L2-3-4)
attachments- from the body of the pubis & inferior pubic ramus to the medial surface of tibia, distal to condyle, proximal to insertion of semitendinosus, lateral to insertion of sartorius
actions- flexes & medially rotates the knee, and adducts hip
innervation- obturator nerve
Pectineus (L2-3-4)
attachments- from superior pubic ramus to the femur between the lesser trochanter & linea aspera (pectineal line)
actions- adducts, flexes hip
innervation- femoral nerve & obturator nerve
Obturator externus (L3-4)
attachments- from rami of the pubis and ischium; external surface obturator membrane to trochanteric fossa
actions- laterally rotates hip
innervation- obturator nerve
Muscles of the Gluteal Region
Superior gemellus (L5-S1-2)
attachments- external surface spine of ischium via obturator internus tendon to greater trochanter
actions- laterally rotates hip
innervation- sacral plexus N. obturator internus
Inferior gemellus (L4-5-S1)
attachments- proximal ischial tuberosity via obturator internus tendon to greater trochanter
actions- laterally rotates hip
innervation- nerve to the quadratus femoris (from sacral plexus)
Gluteus maximus (L5-S1-2)
attachments- from the aponeurosis of the erector spinae, sacrum, sacrotuberous ligament & posterior gluteal line (innominate) to the greater trochanter, gluteal tuberosity of the femur & the iliotibial tract
actions- extends & laterally rotates hip
innervation- inferior gluteal nerve
Gluteus medius (L4-5-S1)
attachments- from the external iliac surface to the oblique ridge on the lateral aspect of the greater trochanter; gluteal aponeurosis
actions- abducts & medially rotates hip; and keeps the pelvis level when opposite leg is raised
innervation- superior gluteal nerve
Gluteus minimis (L4-5-S1)
attachments- from the external iliac surface and margin of the greater sciatic notch to the anterolateral aspect of the greater trochanter
actions- abducts & medially rotates hip; and keeps the pelvis level when opposite leg is raised
innervation- superior gluteal nerve
Obturator internus (L5-S1-2)
attachments- from the anterolateral wall of the pelvis & obturator membrane to the medial surface of the greater trochanter
actions- laterally rotates hip
innervation- nerve to the obturator internus (from sacral plexus)
Piriformis (S1-2)
attachments- from the anterolateral sacrum & posterior inferior iliac spine to the upper border of the greater trochanter
actions- abducts & laterally rotates hip
innervation- nerve to piriformis
Quadratus femoris (L4-5-S1)
attachments- from the ischial tuberosity to the quadrate tubercle of the femur
actions- laterally rotates hip
innervation- nerve to the quadratus femoris (from sacral plexus)
Posterior Femoral Muscles
Biceps femoris (L5-S1-2-3 to long head; L5-S1-2 to short head)
attachments- from the ischial tuberosity & sacrotuberous lig. (long head); lateral lip of linea aspera & lateral supracondylar line (short head) to the lateral side of fibular head
actions- flexes & laterally rotates the knee (both heads) & extends hip (long head only)
innervation- tibial division of sciatic (long head) & fibular division of the sciatic nerve (short head)
Semimembranosus (L4-5-S1-2)
attachments- from ischial tuberosity to posterior aspect of the medial tibial condyle
actions- extends hip, and flexes & medially rotates knee
innervation- tibial division of the sciatic nerve
Semitendinosus (L4-5-S1-2)
attachments- from the ischial tuberosity to the proximal, medial tibia
actions- extends hip, and flexes & medially rotates knee
innervation- tibial division of the sciatic nerve5. And 6. Name the attachments and spinal cord segments of the muscles on the Structure Information List
Anterior Crural Muscles
Extensor digitorum longus (L4-5-S1)
attachments- from the lateral tibial condyle, proximal 3/4th of the fibula and crural interosseous membrane to the dorsal digital expansions of toes 2-5
actions- dorsiflexes ankle, and extends digits 2-5 (IP & MP)
innervation- deep fibular nerve
Extensor hallucis longus (L. hallux, great toe) (L4-5-S1)
attachments- from the middle 1/2 of the fibular surface & crural interosseous membrane to the distal phalangeal base of the 1st toe
actions- dorsiflexes ankle, and extends great toe (MP & IP)
innervation- deep fibular nerve
Fibularis (peroneus) tertius (L4-5-S1)
attachments- from the distal fibula and crural interosseous membrane to the base of the 5th metatarsal
actions- dorsiflexes ankle, and everts foot
innervation- deep fibular nerve
Tibialis anterior (L4-5-S1)
attachments- from the lateral condyle and proximal 2/3rds of the tibia’s lateral surface & crural interosseous membrane to the medial cuneiform & adjacent 1st metatarsal
actions- dorsiflexes ankle, and inverts foot
innervation- deep fibular nerve
Lateral Crural Muscles
Fibularis (peroneus) longus (L4-S1)
attachments- from the head & proximal 2/3rds of the fibula to the lateral aspects of the 1st metatarsal & adjacent medial cuneiform
actions- everts foot, plantar flexes ankle, and depresses 1st metatarsal head
innervation- superficial fibular nerve
Fibularis (peroneus) brevis (L4-S1)
attachments- from the distal 2/3rds of the fibula to the lateral base of the 5th metatarsal
actions- everts foots, plantar flexes ankle
innervation- superficial fibular nerve
Posterior Crural Muscles
Flexor digitorum longus (L5-S2)
attachments- from the posterior tibia distal to the soleal line to the plantar surface of the distal phalangeal bases
actions- plantar flexes ankle, and flexes digits 2-5 (MP & IP)
innervation- tibial nerve
Flexor hallucis longus (L5-S2)
attachments- from the distal 2/3rds of the posterior fibular surface & crural interosseous membrane to the plantar aspect of the distal phalangeal base of the 1st toe
actions- plantar flexes ankle, and flexes great toe (MP & IP)
innervation- tibial nerve
Gastrocnemius (S1-2) (Gr. gaster, belly + knee, leg)
attachments- from the posterior aspect of the femoral condyles and joint capsule to the posterior calcaneal surface
actions- flexes knee, and plantar flexes ankle
innervation- tibial nerve
Plantaris (L4-S1) (L. planta, sole)
attachments- from the lateral supracondylar line to the posterior calcaneal surface
actions- flexes knee, and plantar flexes ankle
innervation- tibial nerve
Popliteus (L4-S1)attachments- from the lateral femoral condyle and oblique popliteal ligament to the soleal line of the tibia
actions- in NWB, medial rotation of tibia and knee flexion; in WB insertion is fixed: lateral rotation of femur and knee flexion; thus, it unlocks the knee from extension into early flexion
innervation- tibial nerve
Soleus (L5-S2)
attachments- from the posterior aspect of the head & proximal 1/4th of the fibula & tibial soleal line to the posterior calcaneal surface
actions- plantar flexes the foot at the ankle joint
innervation- tibial nerve
Tibialis posterior (L4-S1)
attachments- from the crural interosseous membrane, lateral tibial surface & medial fibular surface to the navicular, medial & intermediate cuneiforms and bases of metatarsals 2-4
actions- inverts foot and plantar flexes ankle2. 3 nd 4 Describe the layers of the muscles of the foot and list their contents, general actions, innervation, and blood supply include segmental nerve intervation and muscle attachments
Most Superficial: Plantar Appendrosis
1st layer
Flexor digitorum brevis
(L4-5-S1)
attachments- from medial process of calcaneal tuberosity to sides of intermediate phalanges of digits 2-5
actions- flexes toes (proximal IP)
innervation- medial plantar nerve
Abductor hallucis
(L4-5-S1)
attachments- from medial calcaneal tuberosity to medial side of proximal phalangeal base of great toe
actions- flexes & abducts great toe
innervation- medial plantar nerve
Abductor digiti minimi
(S1-2)
attachments- from calcaneal tuberosity to lateral side of proximal phalangeal base of 5th digit
actions- abducts & flexes 5th digit
innervation- lateral plantar nerve
Inn: lateral/medial plantar nn.
2nd layer
Quadratus plantae
(flexor digitorum accessorius)
(S1-2)
attachments- from medial surface of calcaneus & lateral process of calcaneal tuberosity to long flexor tendons
actions- assists flexor digitorum longus
innervation- lateral plantar nerve
Lumbricals (4)
Arising from flexor digitorum longus
(1st: L4-5-S1; 2nd -4th: S1-2)
attachments- from tendons of flexor digitorum longus to medial sides of dorsal expansions of digits 2-5
actions- flexes proximal phalanges (MP), and extend IP joints
innervation- 1st- medial plantar nerve & 2nd-4th- lateral plantar nerve
Inn: lateral/medial plantar nn.
3rd layer
Adductor hallicis
(S1-2)
attachments- from 2-4th metatarsal bases (oblique head) & distal ends of 3-5 metatarsal (transverse head) to lateral base of the proximal phalanx of great toe
actions- adducts great toe
innervation- lateral plantar nerve
Flexor hallucis brevis
(L4-5-S1)
attachments- from cuboid & tendon of tibialis posterior to base of the proximal phalanx of great toe
actions- flexion of great toe (MP)
innervation- medial plantar nerve
Flexor digitit minimi brevis
(S1-2)
attachments- from 5th metatarsal base to proximal phalangeal base
actions- flexion of 5th digit (MP)
innervation- lateral plantar nerve
Inn: lateral/medial plantar nn.
4th layer
Plantar interossei (3)
(S1-2)
attachments- from plantar surface of base of metatarsals to dorsal digital expansions of digits 3-5
actions- adducts & flexes (MP) digits 3-5
innervation- lateral plantar nerve
Dorsal interossei (4)
Dorsal interossei (S1-2)
attachments- from metatarsal shafts to proximal phalangeal bases & dorsal digital expansions of digits 2-4
actions- abducts (MP) & flexes (MP) digits 2-4
innervation- lateral plantar nerve
ALL innervated by lateral plantar n.
Dorsal aspect
Extensor hallucis brevis
(L4-5-S1)
attachments- from extensor digitorum brevis to dorsal aspect of the base of the proximal phalanx of the hallux
action- extension of great toe at metatarsophalangeal joint
innervation- deep fibular nerve
Extensor digitorum brevis
(L4-5-S1; medial slip of this muscle is extensor hallucis brevis)
attachments- from anterolateral calcaneus to dorsal aspect of the base of the proximal phalanx (digit 1 for EHB) or to the lateral side of tendons of extensor digitorum longus (digits 2-4 for EDB)
actions- extension of digits 2-5 (MP & IP; EDB) and extension of digit 1 (EHB)
innervation- deep fibular nerve
Inn. by deep fibular n.