Muscles Anatomy

• Platysma:

  • Action: tenses skin of neck, depresses mandible
• Frontalis:

  • Origin: epicranial aponeurosis
  • Insertion: eyebrows and nose
  • Action: raises eyebrows, wrinkles forehead
• Orbicularis Oculi:

  • Origin: frontal bone, maxilla, medial palpebial ligament
  • Insertion: adjacent muscles
  • Action: closes eyelids
• Temporoparietalis:

  • Action: tightens scalp
• Nasalis:

  • Action: compresses and dilates nostrils
• Minor Zygomatic:

  • Origin: zygomatic bone
  • Insertion: angle of mouth
  • Action: elevates upper lip
• Major Zygomatic:

  • Origin: zygomatic bone
  • Insertion: angle of mouth
  • Action: elevates angle of mouth
• Orbicularis Oris:

  • Origin: angulus oris and vermilion line
  • Insertion: lips
  • Action: compresses and protrudes lips
• Mentalis:

  • Action: elevates and protrudes the lower lip
• Levator Nasi:

  • Action: elevates and averts upper lip, dilates nostrils
• Levator Labii Superioris:

  • Action: elevates and everts upper lip
• Levator Anguli Oris:

  • Action: elevates angle of mouth
• Depressor Labii Inferioris:

  • Action: depresses lower lip
• Masseter:

  • Action: chewing
• Temporalis:

  • Action: elevates and retracts mandible
• Buccinator:

  • Action: compresses cheeks
• Gluteus Maximus:

  • Origin: ilium
  • Insertion: femur
  • Action: abducts thigh at hip joint
• Tensor Fascia Latae:

  • Action: flexes thigh at hip joint
• Biceps Femoris:

  • Origin: ischial tuberosity, linea aspera, lateral supracondylar line
  • Insertion: fibula
  • Action: flexes leg at knee joint
• Vastus Lateralis:

  • Action: extends leg at knee joint
• Gastrocnemius:

  • Origin: femur
  • Insertion: calcaneus
  • Action: flexes leg at knee joint
• Soleus:

  • Origin: tibia
  • Insertion: calcaneus
  • Action: extends foot at ankle joint
• Tibialis Anterior:

  • Action: flexes foot at ankle joint
• Gluteus Medius:

  • Action: abducts thigh at hip joint
• Piriformis:

  • Action: transversely abducts thigh at hip joint
• Vastus Intermedius:

  • Action: extends leg at knee joint
• Gracialis:

  • Action: flexes leg at knee joint
• Semitendinous:

  • Origin: ischial tuberosity
  • Insertion: tibia
  • Action: flexes leg at knee joint, extends thigh at hip joint
• Quadratus Femoris:

  • Action: laterally rotates thigh at hip joint
• Plantaris:

  • Action: flexes leg at knee joint
• Tibialis Posterior:

  • Action: inverts foot at tarsal joints
• Sartorius:

  • Origin: anterior superior iliac spine
  • Insertion: tibia
  • Action: flexes leg at knee joint, flexes thigh at hip joint
• Rectus Femoris:

  • Origin: anterior inferior iliac spine
  • Insertion: tibial tuberosity
  • Action: extends leg at knee joint, flexes thigh at hip joint
• Vastus Medialis:

  • Action: extends leg at knee joint
• Adductor Longus:

  • Action: adducts thigh at hip joint
• Semimembranous:

  • Action: flexes leg at knee joint, extends thigh at hip joint
• Deltoid:

  • Origin: scapula
  • Insertion: deltoid tuberosity
  • Action: abducts arm at shoulder joint
• Triceps Brachii:

  • Origin: scapula
  • Insertion: decranon
  • Action: extends elbow at forearm joint
• Biceps Brachii:

  • Origin: scapula
  • Insertion: radial tuberosity
  • Action: flexes forearm at elbow joint
• Anconeus:

  • Action: extends elbow at forearm joint