Origins, Insertions, Actions, and Innervations of the Lower Extremities Flashcards
What muscles compose the anterior hip region?
Iliacus, Psoas Major, and Psoas Minor
What is the origin of the iliacus?
- Iliac fossa
- Sacrum
What is the insertion of the iliacus?
Lesser trochanter of the femur
What is the action of the iliacus?
- Flexion of the femur at the hip joint
- Assists in flexion of the vertebral column
- Helps maintain posture (integrity of the spine)
What is the nerve supply of the iliacus?
Femoral nerve
What is the origin of the psoas major?
Bodies and transverse processes of the lumbar vertebrae
What is the insertion of the psoas major?
Lesser trochanter of the femur
What is the action of the psoas major?
- Flexion of the femur at the hip joint
- Assists in flexion of the vertebral column
- Helps maintain posture (integrity of the spine)
What is the nerve supply of the psoas major?
Femoral nerve
What is the origin of the psoas minor?
Bodies of the lumbar vertebrae
What is the insertion of the psoas minor?
Iliopubic eminence of the pubis
What is the action of the psoas minor?
Flexion at the pelvic bone (upward movement)
What is the nerve supply of the psoas minor?
L1 (sometimes L2)
What muscles compose the anterior thigh muscles?
Sartorius, rectus femoris, vastus lateralis, vastus medialis, and vastus lateralis
What is the origin of the sartorius?
Anterior superior iliac spine
What is the insertion of the sartorius?
Superior medial shaft of the tibia
What is the action of the sartorius?
- Abducts and laterally rotates the femur
- Medially rotates the leg
- Assists in flexion of the hip and knee when both are carried out
What is the nerve supply of the sartorius?
Femoral nerve
What is the origin of the rectus femoris?
- Anterior inferior iliac spine
- Acetabulum of the pelvic bone
What is the insertion of the rectus femoris?
Base of the patella
What is the action of the rectus femoris?
- Extends the leg and knee
- Flexion at the hip
- Tonus of muscles play a role in strengthening the knee
What is the nerve supply of the rectus femoris?
Femoral nerve
What is the origin of the vastus lateralis?
- Greater trochanter of the femur
- Linea aspera of the femur
What is the insertion of the vastus lateralis?
Base of the patella
What is the action of the vastus lateralis?
- Extends the leg at the knee
- Tonus of muscles play a role in strengthening the knee
What is the nerve supply of the vastus lateralis?
Femoral nerve
What is the origin of the vastus medialis?
Linea aspera of the femur
What is the insertion of the vastus medialis?
Base of the patella
What is the action of the vastus medialis?
- Extends the leg at the knee
- Tonus of muscles play a role in strengthening the knee
What is the nerve supply of the vastus medialis?
Femoral nerve
What is the origin of the vastus intermedius?
- Antero-lateral aspect of the femur
- Linea aspera of the femur
What is the insertion of the vastus intermedius?
Base of the patella
What is the action of the vastus intermedius?
- Extends the leg at the knee
- Tonus of muscles play a role in strengthening the knee
What is the nerve supply of the vastus intermedius?
Femoral nerve
What muscles compose the medial thigh muscles?
Gracilis, pectineus, adductor longus, addutor brevis, and adductor magnus
What is the origin of the gracilis?
- Ramus of the ischium
- Inferior ramus of the pubis
What is the insertion of the gracilis?
Superior medial shaft of the tibia
What is the action of the gracilis?
- Flexion of the leg
- Adducts the femur
What is the nerve supply of the gracilis?
Obturator nerve
What is the origin of the pectineus?
Superior rami (pubis pectin) of the pubis
What is the insertion of the pectineus?
Pectineal line of the femur
What is the action of the pectineus?
- Adducts the femur
- Flexion of the femur at the hip
What is the nerve supply of the pectineus?
Femoral and obturator nerves
What is the origin of the adductor longus?
Superior ramus of the pubis
What is the insertion of the adductor longus?
Linea aspera of the femur
What is the action of the adductor longus?
Adducts the femur
What is the nerve supply of the adductor longus?
Obturator nerve
What is the origin of the adductor brevis?
Inferior ramus of the pubis
What is the insertion of the adductor brevis?
- Pectineal line of the femur
- Linea aspera of the femur
What is the action of the adductor brevis?
Adducts the femur
What is the nerve supply of the adductor brevis?
Obturator nerve
What is the origin of the adductor magnus?
Rami of the ischium and pubis
What is the insertion of the adductor magnus?
- Linea aspera of the femur
- Adductor tubercle of the femur
What is the action of the adductor magnus?
- Adducts the femur
- Extends the femur at the hip
What is the nerve supply of the adductor magnus?
Obturator and sciatic nerves
What muscles compose the posterior hip (gluteal) region?
Tensor fasica lata, gluteus maximus, gluteus medius, gluteus minimus, piriformis, superior gemellus, obturator internus, inferior gemellus, obturator externus, and quadratus femoris
What is the origin of the tensor fascia lata?
Crest of the ilium
What is the insertion of the tensor fascia lata?
Iliotibial tract
What is the action of the tensor fascia lata?
- Flexes, abducts, and medially rotates the femur
- Helps stabilize the femur
What is the nerve supply of the tensor fascia lata?
Superior gluteal nerve
What is the origin of the gluteus maximus?
- Posterior gluteal line of the ilium
- Sacrum and coccyx
- Posterior ligaments of the SI joint
What is the insertion of the gluteus maximus?
- Gluteal tuberosity of the femur
- Iliotibial tract
What is the action of the gluteus maximus?
- Extends and laterally rotates the femur (for strength when going from sitting to standing)
- Stabilizes the knee
- Helps stabilize the pelvic bone
What is the nerve supply of the gluteus maximus?
Inferior gluteal nerve
What is the origin of the gluteus medius?
External surface of the ilium (between the posterior and anterior gluteal lines)
What is the insertion of the gluteus medius?
Greater trochanter of the femur
What is the action of the gluteus medius?
- Abducts the femur
- Medially rotates the femur
- Helps steady the pelvic bone when the opposite foot is raised off the ground (Trendelenburg test)
What is the nerve supply of the gluteus medius?
Superior gluteal nerve
What is the origin of the gluteus minimus?
External surface of the ilium (between the anterior and inferior gluteal lines)
What is the insertion of the gluteus minimus?
Greater trochanter of the femur
What is the action of the gluteus minimus?
- Abducts the femur
- Medially rotates the femur
- Helps steady the pelvic bone when the opposite foot is raised off the ground (Trendelenburg test)
What is the nerve supply of the gluteus minimus?
Superior gluteal nerve
What is the origin of the piriformis?
Anterior surface of the sacrum
What is the insertion of the piriformis?
Greater trochanter of the femur
What is the action of the piriformis?
Laterally rotates the femur
What is the nerve supply of the piriformis?
S1, S2
What is the origin of the superior gemellus?
Spine of the ischium
What is the insertion of the superior gemellus?
Greater trochanter of the femur
What is the action of the superior gemellus?
Laterally rotates the femur
What is the nerve supply of the superior gemelleus?
L4, L5, S1, S2
What is the origin of the obturator internus?
Internal surface of the obturator membrane
What is the insertion of the obturator internus?
Greater trochanter of the femur
What is the action of the obturator internus?
Laterally rotates the femur
What is the nerve supply of the obturator internus?
L4, L5, S1, S2
What is the origin of the inferior gemellus?
Ischial tuberosity
What is the insertion of the inferior gemellus?
Greater trochanter of the femur
What is the action of the inferior gemellus?
Laterally rotates the femur
What is the nerve supply of the inferior gemellus?
L4, L5, S1, S2
What is the origin of the obturator externus?
External surface of the obturator membrane
What is the insertion of the obturator externus?
Trochanteric fossa of the femur
What is the action of the obturator externus?
Laterally rotates the femur
What is the nerve supply of the obturator externus?
Obturator nerve
What is the origin of the quadratus femoris?
Ischial tuberosity
What is the insertion of the quadratus femoris?
Quadrate tubercle of the femur
What is the action of the quadratus femoris?
Laterally rotates the femur
What is the nerve supply of the quadratus femoris?
L4, L5, S1, S2
What muscles compose the posterior thigh?
Semitendinosus, semimembranosus, and the biceps femoris
What is the origin of the semitendinosus?
Ischial tuberosity
What is the insertion of the semitendinosus?
- Medial condyle of the tibia
- Proximal posterior shaft of the tibia
What is the action of the semitendinosus?
- Flexion of the leg at the knee
- Stabilizes the hip
- Extends the femur
- Medially rotates the leg
What is the nerve supply of the semitendinosus?
Sciatic nerve
What is the origin of the semimembranosus?
Ischial tuberosity
What is the insertion of the semimembranosus?
Medial condyle of the tibia
What is the action of the semimembranosus?
- Flexion of the leg at the knee
- Stabilizes the hip
- Extends the femur
- Medially rotates the leg
What is the nerve supply of the semimembranosus?
Sciatic nerve
What is the origin of the long head of the biceps femoris?
Ischial tuberosity
What is the insertion of the long head of the biceps femoris?
- Head of the fibula
- Lateral condyle of the tibia
What is the action of the long head of the biceps femoris?
- Flexion of the leg at the knee
- Stabilizes the hip
- Extends the femur
- Laterally rotates the leg
What is the nerve supply of the biceps femoris?
Sciatic nerve
What is the origin of the short head of the biceps femoris?
Linea aspera of the femur
What is the insertion of the short head of the biceps femoris?
- Head of the fibula
- Lateral condyle of the tibia
What is the action of the short head of the biceps femoris?
- Flexion of the leg at the knee joint
- Laterally rotates the leg
What is the nerve supply of the short head of the biceps femoris?
Sciatic nerve
What muscles compose the anterior leg?
Tibialis anterior, extensor digitorum longus, fibularis tertius, extensor hallucis longus
What is the origin of the tibialis anterior?
- Shaft of the tibia
- Interosseus membrane
What is the insertion of the tibialis anterior?
- 1st metatarsal
- Medial cuneiform
What is the action of the tibialis anterior?
- Inverts and dorsally flexes the foot
- Supports the medial longitudinal arch
What is the nerve supply of the tibialis anterior?
Deep fibular nerve
What is the origin of the extensor digitorum longus?
- Lateral condyle of the tibia
- Shaft of the fibula
- Interosseus membrane
What is the insertion of the extensor digitorum longus?
Distal phalanges of digits 2-5
What is the action of the extensor digitorum longus?
- Extends digits 2-5
- Dorsally flexes the foot
What is the nerve supply of the extensor digitorum longus?
Deep fibular nerve
What is the origin of the fibularis tertius?
Shaft of the fibula
What is the insertion of the fibularis tertius?
5th metatarsal
What is the action of the fibularis tertius?
Everts and dorsally flexes the foot
What is the nerve supply of the fibularis tertius?
Deep fibular nerve
What is the origin of the extensor hallucis longus?
- Shaft of the fibula
- Interosseus membrane
What is the insertion of the extensor hallucis longus?
Distal phalanx of digit 1
What is the action of the extensor hallucis longus?
- Extends digit 1
- Dorsally flexes the foot
What is the nerve supply of the extensor hallucis longus?
Deep fibular nerve
What muscles compose the lateral leg?
Fibularis longus and fibularis brevis
What is the origin of the fibularis longus?
Shaft and head of the fibula
What is the insertion of the fibularis longus?
- 1st metatarsal
- Medial cuneiform
What is the action of the fibularis longus?
- Everts and plantar flexes the foot
- Supports the lateral and transverse arches
What is the nerve supply of the fibularis longus?
Superificial fibular nerve
What is the origin of the fibularis brevis?
Shaft of the fibula
What is the insertion of the fibularis brevis?
5th metatarsal
What is the action of the fibularis brevis?
- Everts and plantar flexes the foot
- Supports the lateral arch
What is the nerve supply of the fibularis brevis?
Superficial fibular nerve
What muscles compose the superficial posterior leg?
Gastrocnemius, soleus, and plantaris
What is the origin of the gastrocnemius?
Lateral and medial epicondyle of the femur
What is the insertion of the gastrocnemius?
Tuberosity of the calcaneus
What is the action of the gastrocnemius?
- Inverts and plantar flexes the foot
- Stabilizes the ankle
What is the nerve supply of the gastrocnemius?
Tibial nerve
What is the origin of the soleus?
- Soleal line of the tibia
- Shaft and head of the fibula
What is the insertion of the soleus?
Tuberosity of the calcaneus
What is the action of the soleus?
- Inverts and plantar flexes the foot
- Stabilizes the ankle
What is the nerve supply of the soleus?
Tibial nerve
What is the origin of the plantaris?
Lateral supracondylar ridge of the femur
What is the insertion of the plantaris?
Tuberosity of the calcaneus
What is the action of the plantaris?
Inverts and plantar flexes the foot
What is the nerve supply of the plantaris?
Tibial nerve
What muscles compose the deep posterior leg?
Popliteus, flexor digitorum longus, flexor hallucis longus, tibialis posterior
What is the origin of the popliteus?
Lateral epicondyle of the femur
What is the insertion of the popliteus?
Shaft of the tibia
What is the action of the popliteus?
- Medially rotates the tibia (to unlock knee and allow flexion of the leg)
- Stabilizes the knee (prevents hyperextension)
What is the nerve supply of the popliteus?
Tibial nerve
What is the origin of the flexor digitorum longus?
Shaft of the tibia
What is the insertion of the flexor digitorum longus?
Distal phalanges of digits 2-5
What is the action of the flexor digitorum longus?
- Flexes digits 2-5
- Plantar flexes the foot
- Supports the medial and lateral arches
What is the nerve supply of the flexor digitorum longus?
Tibial nerve
What is the origin of the flexor hallucis longus?
- Interosseus membrane
- Shaft of the fibula
What is the insertion of the flexor hallucis longus?
Distal phalanx of digit 1
What is the action of the flexor hallucis longus?
- Flexes digit 1
- Inverts and plantar flexes the foot
- Supports the medial arch
What is the nerve supply of the flexor hallucis longus?
Tibial nerve
What is the origin of the tibialis posterior?
- Interosseus membrane
- Shaft of the fibula and tibia
What is the insertion of the tibialis posterior?
- Navicular
- Cuneiform
- Cuboid
- Metatarsals 2-4
What is the action of the tibialis posterior?
- Inverts and plantar flexes the foot
- Supports the medial arch
What is the nerve supply of the tibialis posterior?
Tibial nerve
What muscles compose the dorsal foot?
Extensor digitorum brevis and extensor hallucis brevis
What is the origin of the extensor digitorum brevis?
Calcaneus
What is the insertion of the extensor digitorum brevis?
Tendons of extensor digitorum longus of digits 2-4
What is the action of the extensor digitorum brevis?
Extends digits 2-4
What is the nerve supply of the extensor digitorum brevis?
Deep fibular nerve
What is the origin of the extensor hallucis brevis?
Calcaneus
What is the insertion of the extensor hallucis brevis?
Proximal phalanx digit 1
What is the action of the extensor hallucis brevis?
Extends digit 1
What is the nerve supply of extensor hallucis brevis?
Deep fibular nerve
What muscles compose the first layer of the plantar foot?
Abductor digiti quinti, abductor hallucis, and flexor digitorum brevis
What is the origin of the abductor digiti quinti?
Calcaneus
What is the insertion of the abductor digiti quinti?
Proximal phalanx of digit 5
What is the action of the abductor digiti quinti?
- Abducts digit 5
- Supports the lateral arch
What is the nerve supply of the abductor digiti quinti?
Lateral plantar nerve
What is the origin of the abductor hallucis?
Calcaneus
What is the insertion of the abductor hallucis?
Proximal phalanx of digit 1
What is the action of the abductor hallucis?
- Abducts digit 1
- Supports the medial arch
What is the nerve supply of the abductor hallucis
Medial plantar nerve
What is the origin of the flexor digitorum brevis?
Calcaneus
What is the insertion of the flexor digitorum brevis?
Middle phalanges of digits 2-5
What is the action of the flexor digitorum brevis?
- Flexes digits 2-5
- Supports the medial and lateral arches
What is the nerve supply of the flexor digitorum brevis?
Medial plantar nerve
What muscles compose the second layer of the plantar foot?
Lumbricals and quadratus plantae
What is the origin of the lumbricals?
Tendons of the flexor digitorum longus
What is the insertion of the lumbricals?
- Tendons of the extensor digitorum longus
- Proximal phalanx of digits 2-5
What is the action of the lumbricals?
- Flexes the MP joints of digits 2-5
- Extends the IP joints of digits 2-5
What is the nerve supply of the lumbricals?
- 1st lumbrical: Medial plantar nerve
- 2nd-4th lumbricals: Lateral plantar nerve
What is the origin of the quadratus plantae?
Calcaneus
What is the insertion of the quadratus plantae?
Tendons of flexor digitorum longus
What is the action of the quadratus plantae?
Assists in flexion of digits 2-5
What is the nerve supply of the quadratus plantae?
Lateral plantar nerve
What muscles compose the third layer of the plantar foot?
Adductor hallucis, flexor digiti quinti brevis, and flexor hallucis brevis
What is the origin of the adductor hallucis?
- Oblique head: metatarsals 2-4 and tendon of the fibularis longus
- Transverse head: lateral 4 MP joints
What is the insertion of the adductor hallucis?
Proximal phalanx of digit 1
What is the action of the adductor hallucis?
- Adducts digit 1
- Flexes digit 1
- Supports the transverse arch
What is the nerve supply of the adductor hallucis?
Lateral plantar nerve
What is the origin of the flexor digiti quinti brevis?
- Cuboid
- 5th metatarsal
- Tendon of fibularis longus
What is the insertion of the flexor digiti quinti brevis?
Proximal phalanx of digit 5
What is the action of the flexor digiti quinti brevis?
Flexes digit 5
What is the nerve supply of the flexor digiti quinti brevis?
Lateral plantar nerve
What is the origin of the flexor hallucis brevis?
- Cuboid
- Cuneiform
What is the insertion of the flexor hallucis brevis?
Proximal phalanx of digit 1
What is the action of the flexor hallucis brevis?
- Flexes digit 1
- Supports the medial arch
What is the nerve supply of the flexor hallucis brevis?
Medial plantar nerve
What muscles compose the fourth layer of the plantar foot?
Dorsal interosseus and Plantar interosseus
What is the origin of the dorsal interosseus?
Metatarsal bones
What is the insertion of the dorsal interosseus?
Proximal phalanx of digits 2-4
What is the action of the dorsal interosseus?
- Flexes their respective digits
- Abducts digits 2-4
What is the nerve supply of the dorsal interosseus?
Lateral plantar nerve
What is the origin of the plantar interosseus?
Metatarsals 3-5
What is the insertion of the plantar interosseus?
Proximal phalanx of digits 3-5
What is the action of the plantar interosseus?
- Flexes their respective digits
- Adducts digits 3-5
What is the nerve supply of the plantar interosseus?
Lateral plantar nerve