The Posterior Thigh

The thigh is divided into 2 physical compartments divided by the

medial and lateral intermuscular septa

-Anterior compartment

-Posterior compartment

The Posterior Compartment of the thigh has two functionally different sets of muscles

•The Adductors

•The Hamstrings

There is no distinct fascial boundary between the two groups

In total the thigh is divided into 3 functional compartments

1. Anterior or Extensor compartment

1. Medial or Adductor compartment

1. Posterior or Flexor compartment

Skin

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

SeptaSeptaSubcutaneous Fat

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

medial intermuscular septum

lateral intermuscular septum

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Anterior / Extensorcompartment

Anterior Compartment

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Anterior / Extensorcompartment

Anterior Compartment

Adductor Compartment

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Anterior / Extensorcompartment

Anterior Compartment

Adductor Compartment

Hamstring Compartment

There are 5 muscles in the Adductor Compartment

There are 5 muscles in the Adductor Compartment

• Gracilis

There are 5 muscles in the Adductor Compartment

• Gracilis

• Adductor Longus

There are 5 muscles in the Adductor Compartment

• Gracilis

• Adductor Longus

• Adductor Brevis

There are 5 muscles in the Adductor Compartment

• Gracilis

• Adductor Longus

• Adductor Brevis

• Adductor Magnus

There are 5 muscles in the Adductor Compartment

• Gracilis

• Adductor Longus

• Adductor Brevis

• Adductor Magnus

• Pectineus

There are 5 muscles in the Adductor Compartment

• Gracilis

• Adductor Longus

• Adductor Brevis

• Adductor Magnus

• Pectineus

(Obturator Externus is a curious little muscle which occupies both the Adductor Compartment and the Gluteal Region)

Gracilis

This is the most medial muscle of the thigh

Anterior View

Gracilis

This is the most medial muscle of the thigh

Anterior View

It originates from the Pubis and Ischium of the Hip Bone

Gracilis

This is the most medial muscle of the thigh

Anterior View

It originates from the Pubis and Ischium of the Hip Bone

It inserts onto the upper part of the Tibia on the medial aspect

Gracilis

This is the most medial muscle of the thigh

Anterior View

It originates from the Pubis and Ischium of the Hip Bone

It inserts onto the upper part of the Tibia on the medial aspect

It adducts the hip and flexes the knee

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Anterior / Extensorcompartment

Anterior Compartment

Hamstring Compartment

GracilisGracilis

Adductor Longus

Anterior View

Originates from the Pubis Inserts onto the shaft of the Femur

Proximally forms part of the floor of the Femoral Triangle

Distally forms part of the floor of the Adductor Canal

Adductor Longus

Anterior View

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Anterior / Extensorcompartment

Anterior Compartment

Hamstring Compartment

Adductor Adductor LongusLongus

Adductor Magnus

Has two functional components

•Hamstring portion

•Adductor Portion

Anterior View

Adductor Magnus

The Adductor Portion

Originates from the ramus of the •Pubis •Ischium

Anterior View

Adductor Magnus

The Adductor Portion

Originates from the ramus of the •Pubis •Ischium

Inserts onto the Femur•Linea Aspera

Anterior View

Adductor Magnus

The Adductor Portion

Originates from the ramus of the •Pubis •Ischium

Inserts onto the Femur•Linea Aspera

Anterior View

Adducts and Medially Rotates the Hip

Adductor Magnus

The Hamstring Portion

Originates from the Ischial Tuberosity

Inserts onto the Adductor Tubercle of the Femur

Extends the Hip

Anterior View

Adductor Magnus

As there are two functional parts, these are supplied by two different nerves

The Adductor Portion by the Obturator Nerve

The Hamstring Portion by the Tibial Component of the Sciatic Nerve

Anterior View

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Anterior / Extensorcompartment

Anterior Compartment

Hamstring Compartment

Adductor MagnusAdductor Magnus

Adductor Brevis

Anterior View

Originates from the Pubis of the Hip Bone

Attaches to the Linea Aspera of the Femur

Adductor Brevis

Anterior View

Originates from the Pubis of the Hip Bone

Attaches to the Linea Aspera of the Femur

Adducts and flexes the Hip Joint

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Anterior / Extensorcompartment

Anterior Compartment

Hamstring Compartment

Adductor BrevisAdductor Brevis

Pectineus

Originates from the Pubis of the Hip Bone

Inserts onto the Pectineal Line on the Femur just below the Lesser Trochanter

Anterior View

Pectineus

Originates from the pectineal surface of the Hip Bone

Inserts onto the Pectineal Line on the Femur just below the Lesser Trochanter

Adducts and Flexes the Hip Joint

Anterior View

(Not seen on the cross-section diagram as it is placed more superiorly)

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Anterior / Extensorcompartment

Anterior Compartment

Hamstring Compartment

Adductor MagnusAdductor Magnus

Adductor BrevisAdductor BrevisAdductor Adductor LongusLongus

GracilisGracilis

The rest of the Posterior Compartment comprises 3 muscles that are collectively known as the Hamstrings and these are covered in another topic (Posterior Thigh – The Hamstrings)

• Semimembranosus

• Semitendinosus

• Biceps Femoris

Femur

SeptaSepta

Thigh compartments

mediallateral

posterior

anterior

Cross section through right

mid-thigh looking towards hip joint

Anterior / Extensorcompartment

Anterior Compartment

Adductor MagnusAdductor Magnus

Adductor BrevisAdductor BrevisAdductor Adductor LongusLongus

GracilisGracilisBiceps Biceps FemorisFemoris

Short HeadShort Head

Biceps Biceps FemorisFemoris

Long HeadLong HeadSemitendinosusSemitendinosusSemimembranosusSemimembranosus

Obturator Externus

Anterior View

Obturator Externus lies behind Adductor Brevis and is deeply

placedIt is not an adductor muscle, but a

weak External Rotator of the Hip Joint

Obturator Externus

Anterior View

Originates from the outer surface of Obturator Membrane and the

adjacent bony rimInserts onto the medial surface of the

Greater Trochanter of the Femur

Nerve Supply

All these muscles are innervated by the same nerve from the Lumbar

Plexus

Obturator Nerve

Adductor Magnus has a dual nerve

supply

Adductor Portion Obturator Nerve

Hamstring Portion Tibial Component Sciatic Nerve

Posterior ViewAnterior View

Summary of Adductor Muscles

PectineusOrigin Pectineal surface of the pubisInsertion Pectineal line of femur below lesser

trochanterAction Adducts the thigh, flexes hip jointNerve Supply Femoral nerve,some innervation

from the obturator nerve (L2, L3, L4)

Blood Supply Medial circumflex femoral branch of femoral artery and obturator artery

GracilisOrigin Inferior ramus of pubis, and

adjacent ramus of ischium

Insertion Medial surface upper tibial shaft, posterior to sartorius

Action Adducts hip, flexes the knee, medially rotates tibia on femur

Nerve Supply Anterior division obturator nerve (L2, L3)

Blood Supply Obturator artery, medial circumflex femoral artery, profunda femoris artery

Adductor BrevisOrigin Inferior ramus and body of pubis

Insertion Upper third linea aspera of femur

Action Adducts and flexes hip jointNerve Supply Anterior division obturator nerve

(L2, L3, L4)Blood Supply Medial circumflex femoral branch

of femoral artery and obturator artery

Adductor LongusOrigin Anterior surface of body of pubis,

just lateral to pubic symphysisInsertion Middle third of linea aspera,

between the more lateral adductor magnus and brevis insertions and the more medial origin of the vastus medialis

Action Adducts, flexes and medially rotates the hip joint

Nerve Supply Anterior division of obturator nerve (L2, L3, L4)

Blood Supply Obturator artery and medial circumflex femoral artery

Adductor MagnusOrigin Adductor portion: Inferior pubic

ramus, ischial ramusHamstring portion: ischial tuberosity

Insertion Adductor portion: Linea aspera and medial supracondylar ridgeHamstring portion: adductor tubercle

Action Adductor portion:adducts and medially rotates hipHamstring portion: extends hip

Nerve Supply Adductor portion: Posterior division of obturator nerve (L2-4)Hamstring portion: tibial nerve portion of sciatic nerve (L4-S3)

Blood Supply Medial circumflex femoral artery, inferior gluteal artery, 1st - 4th perforating arteries, obturator artery, popliteal artery

Obturator ExternusOrigin External surface of obturator

membrane and anterior bony margins of obturator foramen

Insertion Medial surface of greater trochanter of femur

Action Laterally rotates hip; adducts thighNerve Supply Posterior division of obturator

nerve L2, 3, 4Blood Supply Obturator and medial circumflex

femoral arteries