Human Anatomy: Muscles Quiz

Study Notes

Lower Leg Muscles Overview

Includes both anterior and posterior compartments, consisting of various muscle groups with distinct functions and origins.

Key Muscles and Their Functions

Rectus Femoris
- Action: Flexes femur and extends leg.
- Origin: Anterior inferior iliac spine (AIIS) and superior margin of acetabulum.
- Insertion: Tibial tuberosity.
Sartorius
- Aids in flexing, abducting, and laterally rotating the hip.
- Longest muscle in the human body; known as the "tailor's muscle."
Adductor Longus
- Action: Adducts thigh.
- Origin: Pubis near pubic symphysis.
- Insertion: Middle third of linea aspera of femur.
Adductor Magnus
- Action: Adducts thigh; has both adductor and hamstring portions.
- Origin: Ischial tuberosity and inferior ramus of pubis.
- Insertion: Linea aspera and adductor tubercle of femur.
Biceps Femoris
- Action: Extends femur and flexes/laterally rotates leg.
- Two heads: Long head (origin: ischial tuberosity) and short head (origin: linea aspera).
- Insertion: Lateral condyle of tibia and the head of fibula.
Semitendinosus
- Action: Extends femur and flexes/medially rotates leg.
- Origin: Ischial tuberosity.
- Insertion: Proximal medial surface of the tibia.
Semimembranosus
- Action: Extends femur and flexes/medially rotates leg.
- Origin: Ischial tuberosity.
- Insertion: Posterior part of the medial condyle of tibia.
Tibialis Anterior
- Action: Dorsiflexes and inverts foot.
- Origin: Lateral condyle and upper two-thirds of the tibia.
- Insertion: First metatarsal and medial cuneiform.
Extensor Digitorum Longus
- Action: Extends toes and dorsiflexes foot.
- Origin: Lateral condyle of tibia and proximal fibula.
- Insertion: Middle and distal phalanges of toes 2-5.
Peroneus Longus
- Action: Plantarflexes and everts foot.
- Origin: Head and upper two-thirds of fibula.
- Insertion: Base of the first metatarsal and medial cuneiform.
Gastrocnemius
- Action: Plantarflexes foot and flexes leg at the knee.
- Origin: Medial and lateral condyles of femur.
- Insertion: Calcaneus via the Achilles tendon.
Flexor Digitorum Longus
- Action: Flexes toes and assists in plantarflexion.
- Origin: Posterior surface of tibia.
- Insertion: Distal phalanges of toes 2-5.
Flexor Hallucis Longus
- Action: Flexes the big toe and aids in plantarflexion.
- Origin: Lower two-thirds of the fibula.
- Insertion: Distal phalanx of the hallux.
Iliopsoas
- Composed of iliacus and psoas major; major hip flexor.
- Origin: Iliac fossa (iliacus) and lumbar vertebrae (psoas major).
- Insertion: Lesser trochanter of femur.
Gracilis
- Action: Adducts the thigh and flexes knee.
- Origin: Inferior ramus of pubis.
- Insertion: Proximal medial surface of tibia.
Tensor Fasciae Latae
- Action: Flexes and abducts thigh.
- Origin: Anterior part of the iliac crest and anterior superior iliac spine (ASIS).
- Insertion: Iliotibial band, which attaches to the lateral condyle of the tibia.

Vastus Muscle Group

Vastus Lateralis
- Major muscle in the quadriceps group, primarily extends the knee.
Vastus Medialis
- Also part of the quadriceps; helps stabilize the patella during movement.
Vastus Intermedius
- Lies between the vastus lateralis and medialis, deeply located under the rectus femoris; also extends the knee.

Other Notable Muscles

Pectineus
- Action: Flexes and adducts thigh.
- Origin: Superior ramus of pubis.
- Insertion: Pectineal line of femur.
Adductor Brevis
- Action: Adducts thigh.
- Origin: Body and inferior ramus of the pubis.
- Insertion: Proximal part of linea aspera.
Peroneus Brevis
- Action: Everts foot and assists in plantarflexion.
- Origin: Lower two-thirds of the fibula.
- Insertion: Base of the fifth metatarsal.
Soleus
- Action: Plantarflexes the foot.
- Origin: Head and upper quarter of the fibula and the soleal line of the tibia.
- Insertion: Calcaneus via Achilles tendon.
Plantaris
- Action: Weak plantarflexor and assists in flexing the knee.
- Origin: Lateral supracondylar ridge of femur.
- Insertion: Calcaneus via Achilles tendon.
Popliteus
- Action: Medial rotation of tibia and flexes the knee, unlocking the knee from extension.
- Origin: Lateral condyle of femur.
- Insertion: Posterior surface of tibia above the soleal line.
Extensor Hallucis Longus
- Action: Extends the big toe and dorsiflexes the foot.
- Origin: Middle section of fibula.
- Insertion: Distal phalanx of the hallux.
Tibialis Posterior
- Action: Plantarflexes and inverts the foot.
- Origin: Posterior surface of tibia and fibula and interosseous membrane.
- Insertion: Navicular and all cuneiforms, sustains the medial longitudinal arch.

Description

Test your knowledge of human anatomy with this quiz focusing on key muscles such as the Rectus Femoris, Sartorius, and more. Discover their origins, insertions, and functions in the body. Perfect for students in anatomy or related health fields.