Muscles of thigh

post,ant and med

Sartorius

• Origin: ASIS

• Insertion: Pes anserinus (anteromedial tibia)

• Nerve: Femoral (L2–L3)

• Action: Hip flexion, abduction, external rotation; knee flexion

Rectus femoris

• Origin: AIIS

• Insertion: Tibial tuberosity (via patella)

• Nerve: Femoral (L2–L4)

• Action: Hip flexion, knee extension

Vastus lateralis

• Origin: Greater trochanter & lateral lip of linea aspera

• Insertion: Tibial tuberosity (via patella)

• Nerve: Femoral (L2–L4)

• Action: Knee extension

Vastus medialis

• Origin: Intertrochanteric line & medial lip of linea aspera

• Insertion: Tibial tuberosity (via patella)

• Nerve: Femoral (L2–L4)

• Action: Knee extension, patellar stabilization

Vastus intermedius

• Origin: Anterolateral upper 2/3 of Femur,

  lateral lip of Linea aspera

• Insertion: Tibial tuberosity (via patella)

• Nerve: Femoral (L2–L4)

• Action: Knee extension

Pectineus

• Origin: Pecten pubis (superior pubic ramus)

• Insertion: Pectineal line of femur

• Nerve: Femoral (L2–L3)

• Action: Hip adduction, flexion; anterior pelvic tilt

Adductor longus

• Origin: Body of pubis

• Insertion: Middle ⅓ of linea aspera

• Nerve: Obturator (L2–L4)

• Action: Hip adduction, flexion; anterior pelvic tilt

Adductor brevis

• Origin: Body of pubis & inferior pubic ramus

• Insertion: Proximal linea aspera

• Nerve: Obturator (L2–L4)

• Action: Hip adduction

Adductor magnus

• Origin: Inferior pubic ramus, ischial ramus, ischial tuberosity

• Insertion: Linea aspera → adductor tubercle

• Nerve: Obturator (adductor part), Tibial (hamstring part)

• Action: Hip adduction, extension; posterior pelvic tilt

Gracilis

• Origin: Body & inferior ramus of pubis

• Insertion: Pes anserinus

• Nerve: Obturator (L2–L3)

• Action: Hip adduction; knee flexion & medial rotation

Biceps femoris

• Origin:
  

  • Long head: Ischial tuberosity

  • Short head: Linea aspera & lateral supracondylar line

• Insertion: Head of fibula

• Nerve: Tibial (long), Common peroneal (short)

• Action: Knee flexion, lateral rotation; hip extension (long hea

Semitendinosus

• Origin: Ischial tuberosity (common tendon with biceps femoris)

• Insertion: Pes anserinus

• Nerve: Tibial (sciatic)

• Action: Knee flexion, hip extension, medial rotation

Semimembranosus

• Origin: Upper lateral facet of ischial tuberosity

• Insertion: Posterior surface of medial tibial condyle

• Nerve: Tibial (sciatic)

• Action: Knee flexion, hip extension, medial rotation