A&P Lower Muscles OIA

Gluteus maximus

Origin: iliac crest, posterior gluteal line

Insertion: gluteal tuberosity of the femur, iliotibial tract

Action: major hip extensor

Gluteus medius

Origin: iliac crest

Insertion: greater trochanter

Action: abduction at the hip

Tensor fasciae latae

Origin: anterior superior iliac spine

Insertion: iliotibial tract

Action: flexion and medial rotation of hip

Piriformis

Origin: anterior lateral border of the sacrum

Insertion: greater trochanter

Action: lateral rotation of hip

Quadratus femoris

Origin: ischial tuberosity

Insertion: intertrochanteric crest

Action: lateral rotation at hip

Adductor longus

Origin: inferior ramus of the pubis

Insertion: linea aspera of femur

Action: adduction and flexion of hip

Adductor magnus

Origin: ischial tuberosity; Insertion: linea aspera and adductor tubercle; Action: adduction and flexion of the hip

Gracilis

Origin: inferior ramus of the pubis; Insertion: medial surface of the tibia; Action: adduction and medial rotation at the hip, flexion at the knee

Iliacus

Origin: entire surface of the iliac fossa; Insertion: lesser trochanter; Action: flexion at the hip

Psoas

Origin: T12 - L5 vertebrae; Insertion: lesser trochanter; Action: flexion at the hip

Biceps femoris

Origin: ischial tuberosity and linea aspera; Insertion: head of fibula and lateral condyle of tibia; Action: flexion at the knee, extension at the hip

Semitendinosus

Origin: ischial tuberosity; Insertion: proximal medial surface of the tibia; Action: flexion at the knee, extension at the hip

Semimembranosus

Origin: ischial tuberosity; Insertion: medial condyle of the tibia; Action: flexion at the knee, extension at the hip

Sartorius

Origin: anterior superior iliac spine; Insertion: medial surface of the tibia; Action: flexion at the knee

Rectus femoris

Origin: anterior inferior iliac spine; Insertion: tibial tuberosity via the patellar ligament; Action: extension at the knee and flexion of the hip

Vastus intermedius

Origin: anterior and lateral surfaces of the femur; Insertion: tibial tuberosity via the patellar ligament; Action: extension at the knee

Vastus lateralis

Origin: linea aspera; Insertion: tibial tuberosity via the patellar ligament; Action: extension at the knee

Vastus medialis

Origin: linea aspera; Insertion: tibial tuberosity via the patellar ligament; Action: extension at the knee

Tibialis anterior

Origin: lateral condyle of the tibia; Insertion: 1st metatarsal and medial cuneiform; Action: dorsiflexion at the ankle

Gastrocnemius

Origin: femoral condyles; Insertion: calcaneus via the calcaneal tendon; Action: plantar flexion at the ankle

Fibularis longus

Origin: head and proximal shaft of the fibula; Insertion: medial cuneiform and 1st metatarsal; Action: plantar flexion and eversion at the ankle

Soleus

Origin: head and proximal shaft of the fibula and tibia; Insertion: calcaneus via the calcaneal tendon; Action: plantar flexion at the ankle

Fibularis brevis

Origin: midlateral fibular shaft; Insertion: 5th metatarsal; Action: plantar flexion and eversion at the ankle

Tibialis posterior

Origin: posterior surface of the tibia and fibula; Insertion: tarsal and metatarsal bones; Action: plantar flexion and inversion