Canine Muscle Actions

Front 1

Back 1

Sternocephalicus muscle

to move the head up and down and from side to side.

If the muscles contract together they Move the head up and down in a nod

If one muscle contracts on its own it Moves the head to one side on the side that the muscle contracted

Front 2

Back 2

Splenius Muscle

To move the head backwards and forwards

If both of the muscles move together then the dog’s neck will lift and its head will extend.

If only one of the muscles moves then the dog will only move its head and neck to that side.

Front 3

Back 3

Rhomboideus Muscle

Draws scapula up, backward and forward and lifts neck

Pulls the top of the shoulder up, forwards and towards the body

When the shoulder is still it can lift the neck. One side can only pull the neck to that side.

Front 4

Back 4

Omotransversarius muscle

Moves the limb forward and the neck to the side

Front 5

Back 5

Brachiocephalicus muscle

Pulls leg forwards and neck and head down and to one side

Will pull the whole forelimb forwards. The muscle extends the shoulder joint if the neck and head are still.

When the muscles pull from both sides of the body, they pull the neck and head down.

When the muscles only pull from one side of the body, they pull the head and neck to that side.

Front 6

Back 6

Supraspinatus muscle

Extends and stabilizes the shoulder joint

Front 7

Back 7

Infraspinatus Muscle

extend or flex shoulder joint, abduct shoulder, rotate arm laterally and stabilize the shoulder joint.

Rotates the dogs arm in the outward direction

Pulls the leg away from the dogs body

Prevents dislocation of the shoulder joint by stabilizing it.

Front 8

Back 8

Deltoideus Muscle

Makes shoulder joint flex and pulls the foreleg away from the dog’s body

Front 9

Back 9

Biceps Brachii Muscles

Flexes elbow joint and extends shoulder joint

Front 10

Back 10

Triceps Brachii Muscles

Extends and flexes elbow joint

Long Head – Flexes the shoulder joint and extends the elbow joint

Lateral Head – only extends the elbow joint

Front 11

Back 11

Latissimus Dorsi Muscle

pulls leg backwards

Its contraction causes the leg to move backwards.
It also is a contributing muscle to making the leg able to rotate towards the middle.

Front 12

Back 12

Pectoralis Descendens

Advances forelimb and pulls the forelimb to the center of the body

Front 13

Back 13

Pectoralis Transversus Muscle

Pulls forelimb towards the middle line of the body

Front 14

Back 14

Pectoralis Profundus Muscle
Deep Pectoral

Adducts foreleg and moves it backwards with movement

When the Pectoralis Profundus muscle contracts and the limb is supporting weight it makes the body pull forwards and the shoulder will then extend.

When the limb is not supporting any weight and it contracts it will pull the limb towards the head and flex the shoulder joint.

During all movement it will stabilize the foreleg.

Front 15

Back 15

Trapezius Muscle

Draws scapula up, backward and forward and lifts neck

The Trapezius muscle as a whole pulls the shoulder blade upwards. It also is able to hold the shoulder against the body.

Neck section – Pulls it up and forwards

Thoracic section – Pulls it up and backwards

Front 16

Back 16

Longissimus Dorsi Muscle

Stretches and straightens back and loins, lateral flexion

Stretch the vertebral column.

When they contract they will straighten and stabilize the spinal column.

When the muscle contracts to one side the spine will bend to that side.

Front 17

Back 17

Serratus Ventralis

Pulls the top of the shoulder blade forwards, lifts and bends (neck)

Pulls shoulder blade back and down and rotates the blade (chest)

Neck - Pulls the top end of the shoulder blade forwards. Causes the neck to bend to one side. Also lifts the neck.

Chest – Pulls the top part of the shoulder back and down this can cause the shoulder to rotate which will make it move forwards. Causes an interrupted sling from both of the chest muscles, this keeps the body stable and sturdy and raise the chest.

Front 18

Back 18

Gluteus Medius

Pulls the limb away from the body and extends the dog’s hip joint.

This is an important muscle for the dogs rearing, jumping, kicking and moving forwards as it extends the hip joint.

It also pulls the limb away from the dog’s body.

Front 19

Back 19

Superficialis Gluteus muscle

Pulls the limb from body and flexes hip joint.

The Superficialis gluteus muscle flexes the dog’s hip joint and also pulls the limb away from its body.

Front 20

Back 20

Gracilis Muscle

Pulls limb, extends hip, flexes knee joint, extends ankle joint.

flexes the knee joint

Extends the ankle joint

Pulls the hind limb to the middle of the body

Extends the hip joint

Front 21

Back 21

Sartorius Muscle

Flex hip and extend stifle

Pulls the limb towards the midline of the body

Flexes the hip joint

Front 22

Back 22

Quadriceps Femoris

Extend stifle and flex hip

Vastus Medialis, intermedius and lateralis – Extend the knee joint

Rectus Femoris – Extends the knee joint and also flexes the hip joint.

Front 23

Back 23

Tensor Fascae Latae Muscle

Extends knee joint, flexes hip joint

This muscle flexes the hip joint and because it is attached to the patella and the tibia it will extend the knee joint as well.

Front 24

Back 24

Biceps Femoris Muscle Hamstring

Extends hip joint, extends and flexes knee joint and extends ankle joint

The whole muscle extends the hip joint

The knee joint is extended by the upper front fibers.

The ankle joint is extended by the lower rear fibers.

The lower rear fibers could also flex the knee joint

Front 25

Hamstring

Back 25

Semitendinosus Muscle

Extends hip and ankle joint, flexes knee joint and rotates leg inwards

Rotates the dogs leg inwards

Flexes the dogs knee joint

Extends the dog’s hip joint and also its ankle joint.

Front 26

Hamstring

Back 26

Semimembranosus Muscle

Pulls the limb towards the middle of the body, extends hip joint

Pulls the dogs hindlimb towards the middle of its body

Extends the dogs hip joint

Front 27

Back 27

Adductor Muscles of the hind limb

Adduct limb and extend dogs hip and stabilizes hind leg
The adduct muscles are there to adduct the hind leg of the dog (keep it close to the middle) and to extend its hip. This happens but the contraction of these muscles. All this helps to stabilize the dog’s hind leg while he is moving