SCHOOL OF HORTICULTURE, HAIRDRESSING & APPLIED THERAPIES
Anatomy of body muscles
Student name:--------------------------
Course:--------------------------------------------
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Types of Joint Motion

Abduction - To draw away from the mid-line of the body

Adduction -To draw towards the mid-line of the body

Flexion - To bend into the body

Extension - To straighten away from the body

Rotation - To turn around

Supinate - Turn face or palm upwards

Pronate – Turn face down or palm down

Plantar Flexion – Downward movement of big toe

Dorsi-flexion – Upward movement of big toe

Inversion – turn inwards
N.B The body must be in the anatomical position for the above
definitions to be true.
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Anatomical Directions
To describe the relative position of body parts and their movements, it is
essential to have a universally accepted initial reference position. The
standard body position known as the anatomical position serves as this
reference.

Anterior : In front of; toward or at front of the body

Posterior : Behind; or at the backside of the body

Superior: Above; towards the head or upper part of the structure of the
body
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
Inferior : Below; Away from the head or toward the lower part of the
structure or the body

Medial : Toward or at the midline of the ; or on the inner side of a limb

Lateral : Away from the midline of the body; on the outer side of the
body or a limb

Proximal : Closer to the centre of the body (naval) or to the point of
attachment of a limb to the body torso

Distal: Farther from the centre of the body, or from the point of
attachment of a limb to the torso

Superficial: Toward or at the body surface

Deep: Farther away from the body surface; more internal

Dorsum: The posterior surface of something e.g. back of the hand; top
of foot

Palmar: The palm of hand

Plantar: The sole of the foot
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Origin and insertions of muscles
Muscle origin and insertion are terms that describe where the muscle
attaches to the bones / connective tissues.
Generally, the origin is where the muscles "originates" on the body
(usually a bone, but not always) of the stationary part. The insertion is
where the muscle attaches on the bone of the moving lever across a
single, or multiple, joint lines.
When the muscle contracts, it pulls the insertion to the origin.
Origin
Insertion
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The Human skeleton
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Anterior muscles of the leg
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The Quadriceps muscle group
*The four quadriceps muscles are: Vastus Lateralis, Vastus Intermedius,
Vastus Medialis and Rectus Femoris. They all cross the knee joint but
Rectus Femoris is the only one with two heads of origin and that
crosses the hip joint. The quadriceps straightens the knee when rising
from sitting and during walking.
Origin:
 The Vastus group arise from the upper shaft of femur;
 Rectus Femoris arises from Anterior Inferior Iliac Spine and
the rim of the acetabulum.
Insertion:
All insert into the patella, then the patella ligament into the upper anterior part
of tibia (tibial tuberosity)
Action:
All will extend the knee joint but Rectus Femoris will also flex the hip
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Sartorius
Sartorius is the most superficial muscle of the anterior thigh. Sartorius
is so named because it means ‘tailor’ in Latin and its action is to put the
lower limbs in the cross seated position of the tailor.
Origin:
Anterior Superior Iliac Spine
Insertion:
Upper medial part of tibia
Action:

At hip- Flexes, abducts and laterally rotates.

At knee- Flexes and medially rotates.
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The Adductor muscle group
The Adductor muscle group lies on the medial part of the thigh and
consists of the following muscles:





Adductor Longus
Adductor Magnus
Adductor Brevis
Gracilis
Pectineus
Origin:
Anterior part of pubic bone, Adductor Magnus also takes origin
from the ischial tuberosity.
Insertion:

Adductors: Whole length of medial side of femur
 Gracilis: Upper medial surface of tibia
 Pectineus: Upper medial shaft of femur
Action:
 All adductors will Adduct, the three Adductor muscles will
also laterally rotate hip joint
 Gracilis will also flex and medially rotate knee,
 Pectineus will flex hip.
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The Abductor muscle group
The Three Abductor Muscles are known as:
 Tensor Fascia Latae
 Gluteus Medius
 Gluteus Minimus.
Origin:

Tensor Fascia Latae arises from Anterior Superior Iliac
Spine.
 Gluteus Medius arises from upper outer surface of Ilium.
 Gluteus Minimus arises from outer surface of Ilium.
Insertion:



Tensor Fascia Latae joins iliotibial tract which runs to upper
lateral side of the tibia.
Gluteus Medius inserts into the Greater Trochanter of Femur.
Gluteus Minimus inserts into anterior border of Greater
Trochanter.
Action:



Tensor Fascia Latae flexes abducts and medially rotates hip joint.
It tenses the fascia latae, thus stabilising the knee.
Gluteus Medius abducts the hip joint. The Anterior fibres medially
rotate hip joint whilst the posterior fibres slightly laterally rotate
hip joint.
Gluteus Minimus abducts and medially rotates hip joint
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The Hip Flexors
Iliacus and Psoas (Iliopsoas)
The Iliopsoas actually consists of two muscles: the Iliacus and the
Psoas Major (also Psoas Minor if present). Together, they are known as
the Iliopsoas.
Origin:

Psoas Major originates along the lateral surfaces of the vertebral
bodies of T12 and L1-L4 and their associated invertebral discs.
 Psoas minor, present in only some 40 percent of the population,
originates at the transverse processes of L1-L5.
 Iliacus originates in the iliac fossa of the pelvis.
Insertion:


Psoas Major unites with Iliacus at the level of the inguinal
ligament and crosses the hip joint to insert on the lesser
trochanter.
Psoas Minor inserts at the iliopectineal arch, the thickened band
at the iliac fascia .
Action:

Strongest of the hip flexors (Rectus Femoris, Sartorius,
and Tensor fascia latae), Iliopsoas is important for
standing, walking, and running.
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Muscles of the Anterior lower leg and foot
Tibialis Anterior
This muscle lies on the anterior of the shinbone.
Origin:
Upper lateral anterior surface of the Tibia.
Insertion:
Medial edge of front of foot. (Medial Cuneiform bone and base of
first Metatarsal)
Action:
 Dorsiflexes
 Inverts the foot.
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Extensor Digitorum Longus
The Extensor Digitorum Longus is partially separated at the lower
lateral part and is called Peroneus Tertius.
Origin:
Lateral condyle of Tibia.
Insertion:
Phalanges of lateral four Toes.
Action:
 Dorsiflexes ankle joint
 Everts the foot
 Extends four toes.
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Extensor Hallucis Longus
Origin:
Anterior surface of fibula and interosseous membrane.
Insertion:
Distal phalanx of big toe.
Action:



Dorsiflexes
Inverts the foot
Extends big toe.
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Peroneus Longus and Peroneus Brevis
Peroneus Longus is one of the Peroneal muscle group which pass
down the outside of the lower leg and evert (turn out) the foot. It is
also known as Fibularis Longus.
The Peroneus Brevis muscle (or Fibularis Brevis) lies under cover of the
Peroneus Longus.
Origin:

Peroneus Longus arises from head of fibula.

Peroneus Brevis arises from upper 2/3 of fibula.
Insertion:

Peroneus Longus: Base of underside of 1st Metatarsal and
Cuneiforms.

Peroneus Brevis: Base of 5th Metatarsal.
Action:

Eversion.

Plantarflexion.
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Muscles of the Abdomen
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External Oblique and Internal Obique
External Oblique
Internal Oblique
Origin:
 External Oblique: arises from lower eight ribs
 Internal Oblique: from iliac crest, lateral 2/3 of inguinal
Ligament.
Insertion:
 External Oblique: anterior half of iliac crest and into an
Abdominal Aponeurosis that terminates in the Linea Alba
(tendonous band extending downwards from the sternum)

Internal Oblique: bottom 3 or 4 ribs and Linea Alba via the
Aponeurosis.
Action:
 Compresses and supports abdominal viscera against
gravity.
 Contraction of 1 side results in side flexion.
 Contraction of 2 sides results in assisting with trunk
flexion.
 Rotation of opposite side.
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Transversus Abdominus
Origin:
Anterior two thirds of iliac crest, costal cartilages of lower 6
ribs and lateral third of inguinal ligament.
Insertion:
Linea Alba via the abdominal aponeurosis.
Action:
Compresses abdomen helping to support the abdominal viscera
against gravity.
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Rectus Abdominus
The Rectus Abdominus is divided into three or four bellies by tendinous
bands.
Origin:
Pubic crest and symphsis (front of pubic bone)
Insertion:
Xiphoid process (base of sternum). 5th, 6th and 7th costal
Cartilages.
Action:



Trunk flexion
Depresses ribcage
Stabilises pelvis during walking
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Muscles of the Chest
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Pectoralis Major
Along with Pectoralis Minor, Pectoralis Major forms the anterior wall of
the axilla.
Origin:
 Clavicular head: Medial 1/2 or 2/3 of front of clavicle.
 Sternocostal portion: Sternum and adjacent upper six
costal cartilages.
Insertion:
Upper shaft humerus.
Action:
Adducts and medially rotates humerus.


Clavicular portion: flexes, medially rotates and
horizontally adducts humerus towards opposite
shoulder.
Sternocostal portion: Obliquely adducts humerus
towards opposite hip.
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Pectoralis Minor
The Pectoralis Minor is a thin, triangular muscle, situated at the upper
part of the chest, beneath the Pectoralis Major.
Origin:
Anterior surfaces of the sternal end of upper 3-5 ribs
Insertion:
Coracoid process of Scapula
Action:
Draws the scapula down and forward.
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Serratus Anterior
The Serratus Anterior forms the medial wall of the axilla, along with
the upper 5 ribs. It is a large muscle composed of a series of finger
like slips. The lower slips interdigitate with the origin of External
Oblique.
Origin:
Outer, superior borders of upper 8 or 9 ribs.
Insertion:
Anterior costal surface of the medial border of the scapula
and inferior angle of scapula.
Action:



Protracts scapula (pushes it forward on ribs and into
chest wall)
Rotates and abducts scapula.
Flexion of humerus.
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Muscles of the Arm
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Deltoid
The Deltoid muscle is composed of 3 parts; anterior, middle, and
posterior.
Origin:
Clavicle, acromion process and spine of scapula.
Insertion:
Deltoid tuberosity, half way down humerus.
Action:

Anterior fibres: flex and medially rotate humerus.

Middle fibres: abduct at shoulder level after
Supraspinatus has initiated the movement.

Posterior fibres: extend and laterally rotate humerus.
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Biceps Brachii
Biceps Brachii has 2 tendinous heads at its origin and 2 tendinous
insertions.
Origin:

Short head: tip of corocoid process of scapula.

Long head: supraglenoid tubercle of scapula.
Insertion:
Radial tuberosity and deep fascia on medial forearm.
Action:
Flexes and supinates forearm.
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Brachialis
Brachialis lies posterior to Biceps Brachii and is the main flexor of the
elbow joint.
Origin:
Anterior lower shaft of humerus.
Insertion:
Coronoid process and tuberosity of ulna.
Action:
Flexes elbow joint.
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Triceps Brachii
The Triceps muscle originates from 3 heads and is the only muscle at
the back of the arm.
Origin:

Long head: infraglenoid tubercle of scapula.

Lateral head: upper half of posterior shaft of humerus.

Medial head: lower half of posterior shaft of humerus
Insertion:
Olecranon process of ulna.
Action:
Extends elbow joint
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Pronator Teres
These two Pronator muscles, the Pronator Teres and Quadratus, both
pronate the forearm. The Pronator Teres is more of a trouble maker,
because it does the majority of the work.
Origin:
 Humeral head: common flexor origin on medial epicondyle
of humerus.
 Ulnar head: coronoid process of ulna.
Insertion:
Middle lateral surface of radius.
Action:
Pronates and assists in flexion of elbow joint
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Brachioradialis
The Brachioradialis forms the lateral border of the cubital fossa. The
muscle belly is prominent when working against resistance.
Origin:
Anterior aspect of lateral supracondylar ridge of humerus.
Insertion:
Lower lateral end of radius, just above the styloid process.
Action:
 Flexes elbow joint

Assists in pronation and supination of
forearm.
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Wrist Flexors
The muscles that make up the wrist flexors are:

Flexor carpi radialis

Flexor carpi ulnaris

Palmaris longus
All of these muscles attach to the medial epicondyle of the humerus.
Strain at this attachment is known as Golfer's elbow.
Origin:
Common flexor origin at medial epicondyle of humerus
Insertion:
Carpals, metacarpals, phalanges.
Action:
Wrist flexion
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Wrist Extensors
The muscles that make up the wrist extensors are:

Extensor carpii radialis longus

Extensor carpii radialis brevis

Extensor carpii ulnaris
All these muscles attach to the lateral epicondyle. When these
attachments are strained, it is called Tennis elbow.
Origin:
Common extensor tendon from lateral epicondyle of humerus.
Insertion:
Dorsal surface of metacarpal bones.
Action: Wrist extension.
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Muscles of the posterior leg
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The Hamstrings
The Hamstrings consist of three muscles. From medial to lateral they
are: Semi – membranosus, Semi – tendonosus and Biceps Femoris.
Origin:
Ischial tuberosity. Biceps Femoris also originates from back of
femur.
Insertion:

Semi – membranosus: back of medial condyle of tibia.

Semi – tendonosus: upper medial surface of shaft of tibia.

Biceps Femoris: head of fibula and lateral condyle of tibia
Action:
Flex the knee joint and extend the hip
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Muscles of the posterior calf
Gastrocnemius
The Gastrocnemius muscle forms the prominent contour of the calf.
Origin:

Medial head: lower posterior surface of femur above medial
condyle.

Lateral head: lateral condyle of femur.
Insertion:
Posterior surface of calcaneous (heel bone) via the calcaneal
tendon (Achilles).
Action:
Plantar flexion of ankle joint and assists in knee flexion
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Soleus
The Soleus muscle is frequently in contraction during standing to offset
the line of pull through the body’s centre of gravity.
Origin:
Upper posterior surfaces of tibia and fibula.
Insertion:
With Gastrocnemius via the calcaneal tendon into posterior
surface of calcaneus.
Action:
Plantar flexion of ankle joint
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Tibialis Posterior
Tibialis posterior is the deepest muscle on the back of the leg. It helps to
maintain the arches of the foot.
Origin:
Posterior surface of tibia and fibula and most of interosseous
membrane.
Insertion:
Tarsal bones and 2nd, 3rd and 4th metatarsal.
Action:
Plantar flexion of ankle joint and inversion of foot.
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Flexor Digitorum Longus
There are three muscles responsible for supporting the arches of the
feet that are located in the deep posterior compartment of the lower leg:

Tibialis Posterior (Tom),

Flexor Digitorum Longus (Dick)

Flexor Hallucis Longus (Harry).
Origin:
Medial part of posterior surface of tibia
Insertion:
Distal phalanges of 2nd to 5th toes
Action:

Plantar flexion of ankle joint

Flexes all joints of lateral 4 toes.

Inversion of foot
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Flexor Hallucis Longus
This muscle helps support medial longitudinal arch of foot.
Origin:
2/3 posterior surface of fibula and interosseous membrane.
Insertion:
Distal phalanx of big toe.
Action:

Plantar flexion of ankle joint.

Flexes big toe.

Inversion of foot and stabilise inside of ankle
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Muscles of posterior hip
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Gluteus Maximus
The Gluteus Maximus is the most coarsely fibred and heaviest muscle in
the body forming the bulk of the buttocks.
Origin:
Outer surface of ilium and over sacroiliac joint.
Insertion:
Upper posterior of femur and Iliotibial tract.
Action:
Extends and laterally rotates hip joint.
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Piriformis
The Piriformis is situated partly within the pelvis against its posterior
wall, and partly at the back of the hip-joint.
Origin:
Anterior surface of lateral sacrum.
Insertion:
Upper Medial surface of Greater Trochanter
Action:


Lateral rotation of Thigh.
Abduction of hip when the thigh is flexed.
The sciatic nerve runs very close to this muscle and in some people
(around 10% of the population) it passes straight through the muscles'
fibres! If the Piriformis muscle becomes tight it can put pressure on the
sciatic nerve and cause pain which can radiate down the leg, commonly
known as sciatic pain.
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Muscles of the upper shoulder and neck
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Trapezius
The left and right Trapezius as a whole creates a trapezium in shape
thus giving the muscle its name.
Origin:
Occipital bone, spinous process of C7 and all thoracic vertebrae.
Insertion:
Lateral 1/3 of Clavicle, acromion process, spine of scapula.
Action:

Upper fibres: elevate the scapula

Middle fibres: adduct (retract) scapula

Lower fibres : depress the scapula

Upper and lower together : rotate scapula
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Levator Scapula
Levator scapulae are deep to Sternocleidomastoid and Trapezius
and are named after its action of elevating the scapula.
Origin:
Transverse process of C1 – C4.
Insertion:
Upper medial border of scapula.
Action:

Elevates scapula

Helps retract scapula

Side flexion of neck
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The Rhomboids
The Rhomboids are a parallelogram with oblique angles and the
opposite sides are equal. (Rhomboid major - larger muscle, Rhomboid
minor - smaller muscle). The common problem is that these muscles
tend to get over stretched rather than tight.
Origin:

Rhomboid minor - spinous processes of the C7 to T1 vertebrae

Rhomboid major - spinous processes of the T2 to T5 vertebrae
Insertion: Medial border of scapula
Action:

Retracts(adducts) scapula

Stabilises scapula
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Rotator Cuff
The Rotator cuff muscles are:

Supraspinatus

Infraspinatus

Teres Minor

Subscapularis
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Supraspinatus
A member of the Rotator Cuff. The Rotator Cuff helps hold the head of
the humerus in contact with the glenoid cavity (socket of shoulder joint)
of the scapula during movements of the shoulder, thus helping to
prevent dislocation of the joint.
Origin: Supraspinous fossa of scapula.
Insertion: Greater tubercle at top of humerus.
Action:
Initiates the process of abduction at the shoulder joint, so that Deltoid
can take over at the later stages of abduction.
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Infraspinatus
A member of the Rotator Cuff. The Rotator Cuff helps hold the head of
the humerus in contact with the glenoid cavity (socket of shoulder joint)
of the scapula during movements of the shoulder, thus helping to
prevent dislocation of the joint.
Origin:
Middle 2/3rds of the dorsal surface of scapula, below the spine of
scapula.
Insertion:
Greater tubercle at top of humerus
Action:

As a Rotator cuff helps prevent posterior dislocation of shoulder
joint

Laterally rotates humerus.
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Teres minor
A member of the Rotator Cuff. The Rotator Cuff helps hold the head of
the humerus in contact with the glenoid cavity (socket of shoulder joint)
of the scapula during movements of the shoulder, thus helping to
prevent dislocation of the joint.
Origin:
Upper 2/3rds of lateral edge of the dorsal surface of scapula.
Insertion:
Back of Greater tubercle of humerus
Action:

As a Rotator cuff helps prevent upward dislocation of shoulder
joint.

Laterally rotates humerus

Weakly adducts.
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Subscapularis
A member of the Rotator Cuff. The Rotator Cuff helps hold the head of
the humerus in contact with the glenoid cavity (socket of shoulder joint)
of the scapula during movements of the shoulder, thus helping to
prevent dislocation of the joint.
Origin:
Subscapular fossa (anterior surface of scapula).
Insertion:
Lesser tubercle at top of humerus.
Action:

As a Rotator cuff it stabilises shoulder joint.

Prevents the head of humerus being pulled upwards by the
Deltoid, Biceps and long head of Triceps.

Medially rotates humerus.
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Muscles of the mid/lower back
These muscles are:
 Teres major
 Latissimus dorsi
 Quadratus lumborum
 Erector spinae muscle group
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Teres major
Origin:
Lower 1/3 of the posterior lateral border of scapula.
Insertion:
Bicipital groove of humerus.
Action:

Adducts and medially rotates humerus.

Extends humerus from a flexed position.
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Latissimus Dorsi
The Latissimus Dorsi is one of the chief climbing muscles since it pulls
the shoulders downwards and backwards. It also pulls the trunk up to
the fixed arms.
Origin:
A broad sheet of tendon attached to:

Spinous processes of lower 6 thoracic vertebrae

T7 – S5 vertebrae

Posterior iliac crest

Lower 3 or 4 ribs

Inferior angle of scapula
Insertion:
Bicipital groove of humerus.
Action:

Extends the flexed arm.

Adducts and medially rotates humerus
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SCHOOL OF HORTICULTURE, HAIRDRESSING & APPLIED THERAPIES
Quadratus Lumborum
Origin:
Iliac crest.
Insertion:

12TH rib

Transverse processes of four lumbar vertebrae(L1 – L4)
Action:

Side flexion of vertebral column.

Fixes 12th rib during deep respiration

Helps extend lumbar part of vertebral column and gives it
lateral stability.
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SCHOOL OF HORTICULTURE, HAIRDRESSING & APPLIED THERAPIES
Erector Spinae (Sacrospinalis)
The Erector spinae group is made up of three muscles, the Spinalis
most medially, the Longissimus in the center, and Iliocostalis laterally.
Origin: (collectively)
Slips of muscle arising from:

Sacrum

Iliac crest

Spinous and transverse processes of vertebrae

Rib
Insertion: (collectively)

Ribs

Transverse and spinous processes of vertebrae

Occipital bone
Action:

Extends and side flexes vertebral column.

Helps maintain correct curvature of spine in the erect
and sitting positions.

Steadies the vertebral column on pelvis during walking.
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