Thigh Anatomy Flashcards
Semitendinosis
Origin: Ischial tuberosity
Insertion: Superior part of medial surface of tibia (pes anserinus)
Nerve: Tibial nerve (L5, S1, S2)
Action: Extends thigh; flex leg and rotate it medially when knee is flexed
Adductor longus
Origin: Body of pubis inferior to pubic crest
Insertion: Middle third of linea aspera of femur
Nerve: Obturator nerve (L2, L3, L4)
Action: Adducts thigh
Psoas Major
Origin: Side of T12-L5 vertebrae and discs between them; transverse process of all lumbar vertebrae
Insertion: Lesser trochanter of femur
Nerve: Anterior rami of lumbar nerves (L1, L2, L3)
Action: Acts jointly in flexing thigh at hip joint and in stabilizing this joint
Pectineus
Origin: Pectineal line of pubis
Insertion: Pectineal line of femur
Nerve: Femoral nerve (L2, L3); may receive branch from obturator nerve
Action: Adducts and flexes thigh; assists with medial rotation of thigh
Gracilis
Origin: Body and inferior ramus of pubis
Insertion: Superior part of medial surface of tibia (pes anserinus)
Nerve: Obturator nerve (L2, L3)
Action: Adducts thigh; flexes leg; helps rotate leg medially
Biceps femoris (Long head)
Origin: Ischial tuberosity
Insertion: Lateral side of head of fibula
Nerve: Tibial nerve (L5, S1, S2)
Action: Extends thigh; flex leg and rotate it laterally when knee is flexed
Semimembranosus
Origin: Ischial tuberosity
Insertion: Posterior part of medial condyle of tibia; reflected attachment forms the oblique popliteal ligament
Nerve: Tibial Nerve (L5, S1, S2)
Action: Extends thigh; flex leg and rotate it medially when knee is flexed
Vastus Medialis
Origin: Intertrochanteric line and medial lip of linea aspera of femur
Insertion: Base of patella via quadriceps tendon; indirectly via patellar ligament to tibial tuberosity
Nerve: Femoral Nerve (L2, L3, L4)
Action: Extend leg at knee joint
Sartorius
Origin: Anterior superior iliac spine
Insertion: Superior part of medial surface of tibia (pes anserinus)
Nerve: Femoral nerve (L2, L3)
Action: Flexes, abducts, and laterally rotates thigh at hip joint; flexes leg at knee joint, (medially rotates leg when knee is flexed)
Vastus Intermedius
Origin: Anterior and lateral surfaces of shaft of femur
Insertion: Base of patella via quadriceps tendon; indirectly via patellar ligament to tibial tuberosity
Nerve: Femoral nerve (L2, L3, L4)
Action: Extend leg at knee joint
Adductor Brevis
Origin: Body and inferior ramus of pubis
Insertion: Pectineal line of femur and proximal part of linea aspera of femur
Nerve: Obturator nerve (L2, L3, L4)
Action: Adducts thigh; some extent flexes it
Adductor Magnus (Hamstring Part)
Origin: Ischial tuberosity
Insertion: Adductor tubercle of femur
Nerve: Tibial Nerve (L4)
Action: Adducts and extends thigh
Biceps Femoris (short head)
Origin: Linea aspera and lateral supracondylar line of femur
Insertion: Lateral side of head of fibula
Nerve: Common fibular nerve (L5, S1, S2)
Action: Extend thigh; flex leg and rotate it laterally when knee is flexed
Psoas Minor
Origin: Side of T12-L1 vertebrae and intervertebral discs
Insertion: Pectineal line on pubic and iliopubic eminence via iliopectineal arch
Nerve: Anterior rami of lumbar nerves (L1, L2)
Action: Weak trunk flexor
Iliacus
Origin: Iliac crest, iliac fossa, ala of sacrum, and anterior SI ligaments
Insertion: Tendon psoas major, lesser trochanter and femur distal to it
Nerve: Femoral Nerve (L2, L3)
Action: Acts jointly in flexing thigh at hip joint and in stabilizing this joint
