Muscles of the Thigh

Origin, Insertion, Actions and Innervation

ADDUCTOR GROUP

Adductor Brevis

Origin:
Inferior ramus of pubis

Insertion:
Pectineal line and medial lip of linea aspera

Actions:
ADDUCT the hip at the coxal joint
MEDIALLY ROTATE the hip at the coxal joint
Assist to FLEX the hip at the coxal joint

Innervation:
Obturator Nerve

Adductor Longus

Origin:
Pubic tubercle

Insertion:
Medial lip of the linea aspera

Actions:
ADDUCT the hip at the coxal joint
MEDIALLY ROTATE the hip at the coxal joint
Assist to FLEX the hip at the coxal joint

Innervation:
Obturator Nerve

Adductor Magnus

Origin:
Inferior ramus of the pubis
Ramus of ischium
Ishial tuberosity

Insertion:
Medial lip of the linea aspera
Adductor tubercle

Actions:

All Fibers –
ADDUCT the hip at the coxal joint
MEDIALLY ROTATE the hip at the coxal joint
Assist to FLEX the hip at the coxal joint

Posterior Fibers –
EXTEND the hip at the coxal joint

Innervation:
Obturator Nerve

Gracilis

Origin:
Inferior Ramus of the Pubis

Insertion:
Proximal, medial shaft of tibia at pes anserinus tendon

Actions:
ADDUCT the hip at the coxal joint
MEDIALLY ROTATE the hip at the coxal joint
FLEX the knee at the tibiofemoral joint
MEDIALLY ROTATE the Flexed knee at the tibiofemoral joint

Innervation:
Obturator Nerve

HAMSTRINGS GROUP

Biceps Femoris

Origin:

Long Head –
Ischial tuberosity

Short Head –
Lateral lip of the linea aspera

Insertion:
Head of the fibula

Actions:
FLEX the knee at the tibiofemoral joint
LATERALLY ROTATE the Flexed knee at the tibiofemoral joint

Long Head –
EXTEND the hip at the coxal joint
Assist to LATERALLY ROTATE the hip at the coxal joint
TILT the pelvis POSTERIORLY

Innervation:
Long Head – Sciatic Nerve (tibial branch)
Short Head – Sciatic Nerve (fibular branch)

Semimembranosus

Origin:
Ischial tuberosity

Insertion:
Posterior aspect of the medial condyle of the tibia

Actions:
FLEX the knee at the tibiofemoral joint
MEDIALLY ROTATE the Flexed knee at the tibiofemoral joint
EXTEND the hip at the coxal joint
Assist to MEDIALLY ROTATE the hip at the coxal joint
TILT the pelvis POSTERIORLY

Innervation:
Sciatic Nerve (tibial branch)

Semitendinosus

Origin:
Ischial tuberosity

Insertion:
Proximal, medial shaft of the tibia at the pes anserinus tendon

Actions:
FLEX the knee at the tibiofemoral joint
MEDIALLY ROTATE the Flexed knee at the tibiofemoral joint
EXTEND the hip at the coxal joint
Assist to MEDIALLY ROTATE the hip at the coxal joint
TILT the pelvis POSTERIORLY

Innervation:
Sciatic Nerve (tibial branch)

Pectineus

Origin:
Superior ramus of the pubis

Insertion:
Pectineal line of the femur

Actions:
ADDUCT the hip at the coxal joint
MEDIALLY ROTATE the hip at the coxal joint
Assist to FLEX the hip at the coxal joint

Innervation:
Femoral Nerve
Obturator Nerve

Sartorius

Origin:
ASIS (Anterior Inferior Illiac Spine)

Insertion:
Proximal, medial shaft of the tibia at the pes anserinus tendon

Actions:
FLEX the hip at the coxal joint
LATERALLY ROTATE the hip at the coxal joint
ABDUCT the hip at the coxal joint
FLEX the knee at the tibiofemoral joint
MEDIALLY ROTATE the Flexed knee at the tibiofemoral joint

Innervation:
Femoral Nerve

Tensor Fascia Latae

Origin:
Iliac crest, posterior to the ASIS

Insertion:
Iliotibial tract/band

Actions:
FLEX the hip at the coxal joint
MEDIALLY ROTATE the hip at the coxal joint
ABDUCT the hip at the coxal joint

Innervation:
Superior Gluteal Nerve

QUADRICEPS GROUP

Rectus Femoris

Origin:
AIIS (Anterior Inferior Iliac Spine)

Insertion:
Tibial Tuberosity (via the patella and patellar ligament)

Actions:
FLEX the hip at the coxal joint
EXTEND the knee at the tibiofemoral joint

Innervation:
Femoral Nerve

Vastus Intermedius

Origin:
Anterior and lateral shaft of the femur

Insertion:
Tibial Tuberosity (via the patella and patellar ligament)

Actions:
EXTEND the knee at the tibiofemoral joint

Innervation:
Femoral Nerve

Vastus Lateralis

Origin:
Lateral lip of the linea aspera
Gluteal tuberosity
Greater trochanter

Insertion:
Tibial Tuberosity (via the patella and patellar ligament)

Actions:
EXTEND the knee at the tibiofemoral joint

Innervation:
Femoral Nerve

Vastus Medialis

Origin:
Medial lip of the linea aspera

Insertion:
Tibial Tuberosity (via the patella and patellar ligament)

Actions:
EXTEND the knee at the tibiofemoral joint

Innervation:
Femoral Nerve