Lower Limb Muscles

• Adductor longus

  • Origin: medial portion of the superior pubic ramus
  • Insertion: linea aspera of the femur
  • Action: adducts, flexes, and medially rotates the femur
• Adductor magnus

  • Origin: ischiopubic ramus and ischial tuberosity
  • Insertion: linea aspera of the femor; the ischiocondylar part inserts on the adductor tubercle of the femur
  • Action: adducts, flexes, and medially rotates the femur; extends the femur (ischiocondylar part)
• Adductor minimus

  • Origin: lower portion of the inferior pubic ramus
  • Insertion: gluteal ridge and upper part of the linea aspera of the femur
  • Action: adducts and laterally rotates the femur
• Biceps femoris

  • Origin: long head: ischial tuberosity; short head: lateral lip of the linea aspera
  • Insertion: head of fibula and lateral condyle of the tibia
  • Action: extends the thigh; flexes the leg
• Gluteus maximus

  • Origin: posterior gluteal line, posterior surface of the sacrum and coccyx, sacrotuberous ligament
  • Insertion: upper fibers: iliotibial tract; lowermost fibers: gluteal tuberosity of the femur
  • Action: extends the thing; laterally rotates the femur
• Gluteus medius

  • Origin: external surface of the ilium between the posterior and anterior gluteal lines
  • Insertion: greater trochanter of the femur
  • Action: abducts the femur; medially rotates the thigh
• Gluteus minimus

  • Origin: external surface of the ilium between the anterior and inferior gluteal lines
  • Insertion: greater trochanter of the femur
  • Action: abducts the femur; medially rotates the thigh
• Gracilis

  • Origin: pubic symphysis and the inferior pubic ramus
  • Insertion: medial surface of the tibia (via pes anserinus)
  • Action: adducts the thigh, flexes and medially rotates the thigh, flexes the leg
• Iliacus

  • Origin: iliac fossa and iliac crest; ala of the sacrum
  • Insertion: lesser trochanter of the femur
  • Action: flexes the thigh; if the thigh is fixed it flexes the pelvis on the thigh
• Iliopsoas

  • Origin: iliac fossa; bodies and transverse processes of lumbar vertebrae
  • Insertion: lesser trochanter of the femur
  • Action: flexes the thigh; flexes and laterally bends the lumbar vertebral column
• Psoas Major

  • Origin: bodies and transverse processes of lumbar vertebrae
  • Insertion: lesser trochanter of femur (with iliacus) via iliopsoas tendon
  • Action: flexes the thigh; flexes and laterally bends the lumbar vertebral column
• Psoas Minor

  • Origin: bodies of the T12 and L1 vertebrae
  • Insertion: iliopubic eminence at the line of junction of the ilium and the superior pubic ramus
  • Action: flexes and laterally bends the lumbar vertebral column
• Quadratus femoris

  • Origin: lateral border of the ischial tuberosity
  • Insertion: quadrate line of the femur below the intertrochanteric crest
  • Action: laterally rotates the thigh
• Quadriceps femoris:

  • Origin: anterior surface of the femur and the anterior side of the medial and lateral intermuscular septa
  • Insertion: tibial tuberosity via the patellar tendon
  • Action: extends the knee; rectus femoris flexes the thigh
• Rectus femoris

  • Origin: straight head: anterior inferior iliac spine; reflected head: above the superior rim of the acetabulum
  • Insertion: patella and tibial tuberosity (via the patellar tendon)
  • Action: extends the leg, flexes the thigh
• Sartorius

  • Origin: anterior superior iliac spine
  • Insertion: medial surface of the tibia (pes anserinus)
  • Action: flexes, abducts and laterally rotates the thigh; flexes the leg
• Semimembranosus

  • Origin: upper, outer surface of the ischial tuberosity
  • Insertion: medial condyle of the tibia
  • Action: extends the thigh, flexes the leg
• Semitendinosus

  • Origin: lower, medial surface of ischial tuberosity (common tendon with biceps femoris m.)
  • Insertion: medial surface of tibia (via pes anserinus)
  • Action: extends the thigh, flexes the leg
• Tensor fasciae latae

  • Origin: anterior part of the iliac crest, anterior superior iliac spine
  • Insertion: iliotibial tract
  • Action: flexes, abducts, and medially rotates the thigh
• Vastus intermedius

  • Origin: anterior and lateral surface of the femur
  • Insertion: patella
  • Action: extends the leg
• Vastus lateralis

  • Origin: lateral intermuscular septum, lateral lip of the linea aspera and the gluteal tuberosity
  • Insertion: patella and medial patellar retinaculum
  • Action: extends leg
• Vastus medialis

  • Origin: medial intermuscular septum, medial lip of the linea aspera
  • Insertion: patella and medial patellar retinaculum
  • Action: extends leg