ORIGINS AND INSERTIONS OF MUSCLES
2024/2025 LATEST GRADED A+.
Gastrocnemius - Answ A: plantarflexes and inverts foot at ankle, O:femoral
condyles
I: Calcaneus via achilles tendon
Soleus - Answ A: plantarflexes and inverts foot at ankle
O: Upper 1/3 of fibia
I: Calcaneus via achilles tendon
Tibialis Anterior - Answ A: Dorsiflexes and inverts foot at ankle
O: Lateral condyle of tibia
I: plantar surface of first metatarsal and cuneiform
Tibialis Posterior - Answ A: Inverts and plantarflexes the foot at ankle.
Medial ankle stabilizer.
O: Lateral part of posterior surface of tibia, proximal 2/3 of medial surface
of fibula.
I: Tuberosity of navicular, with branches to sustenaculum tali of calcaneus,
plantar surfaces of all 3 cuneiforms, cuboid, and bases of 2nd, 3rd, and 4th
metatarsal bones.
Popliteus - Answ A: Rotates tibia medially on the femur, or femur laterally
on tibia. Brings knee out of full extension. Helps with posterior stability of
knee
O: Lateral condyle of the femur
I: Posterior surface of tibia above soleal line.
Plantaris - Answ A: plantar flexes and inverts the foot at the ankle, flexes
the leg at the knee.
O: Lower part of lateral supracondylar line of femur, and oblique popliteal
ligament of knee.
I: Posterior part of the calcaneus medial to the achilles tendon.
,Peroneus Longus - Answ A: Eversion and plantar flexion of foot at ankle.
Gives lateral stability to the ankle.
O: Head and proximal 2/3 of lateral tibia
I: Lateral margin of plantar surface of 1st cuneiform and metatarsal.
Peroneus Brevis - Answ A: Eversion and plantar flexion of the foot at the
ankle. Gives lateral stability to the ankle.
O: Distal 2/3 of the lateral fibula.
I: Tuberosity on lateral side of 5th metatarsal
Peroneus Tertius - Answ A: Dorsiflexes and everts the foot at the ankle.
O: Distal 1/3 of anterior surface of fibula.
I: Dorsal surface of 5th metatarsal.
Extensor Hallucis Longus - Answ A: Extends distal phalanx of big toe.
Continued action extends proximal phalanx and dorsiflexes and inverts the
foot at the ankle.
O: Middle 1/2 of the anterior surface of fibula,
I: Dorsal surface of base of distal phalanx of hallux (big toe)
Extensor Digitorum Longus - Answ A: Extends the lateral 4 toes.
Dorsiflexes and everts foot at the ankle.
O: Lateral condyle of tibia, head and proximal 3/4 of the anterior surface of
fibula.
I: Divides into 4 tendons after passing under extensor retinaculum to insert
on dorsal surfaces of bases of middle and distal phalanges of the 2nd-5th
toes.
Flexor Hallucis Longus - Answ Action:
Flexion of great toe
Plantar flexion of foot
Inversion of foot
Origin:
Fibula (posterior shaft)
Interosseous membrane
Insertion:
Distal phalanx of great toe
Comment:
Powerful muscle for "push-off" of foot during walking and running
, Flexor Digitorum Longus - Answ Action:
Flexion of toes 2-5
Plantar flexion of foot
Inversion of foot
Origin:
Tibia (posterior middle shaft)
Insertion:
Distal phalanges of toes 2-5
Comment:
Tendon provides attachment for quadratus plantae (insertion) and lumbrical
(origin) muscles
Vastus Medialis - Answ A: Extends leg at knee and draws patella medially.
O: Lower 1/2 of intertrochanteric line, tendons of adductor magnus and
adductor longus
I: Medial border of the patella and through the ligamentum patallae into
tibial tuberosity
Vastus Intermedius - Answ A: Extends leg at the knee
O: Proximal 2/3 of anterolateral surface of femur, upper part of lateral
supracondylar line
I: by tendons of the rectus and vasti muscles into the superior border of
patella and through patellar ligament into tibial tuberosity.
Vastus Lateralis - Answ A: Extends leg at the knee and draws patella
laterally
O: Upper part of intertrocheanteric line, anterior and lower borders of
greater trochanter, tendon of gluteus maximus
I: Lateral border of the patella and through the patellar ligament into the
tibial tuberosity
Rectus Femoris - Answ A: Extension of leg at knee. Flexion of thigh at hip
O: Straight head: anterior inferior iliac spine
Reflected head: Groove on upper brim of acetabulum
I: Upper border of patella and through patellar ligament into tibial tuberosity
Semimembranosus - Answ A: Flexes and Medially rotates the leg at the
knee. Extends, adducts and medially rotates the thigh at the hip.
O: Upper and lateral aspect of ischial tuberosity
I: Posterior surface of medial condyle of the tibia