Unit 1 – The Human Body in Motion

AREA OF STUDY 1 - HOW DOES THE MUSCULOSKELETAL SYSTEM WORK TO PRODUCE MOVEMENT?

The Skeletal System

AREA OF STUDY 1 - HOW DOES THE MUSCULOSKELETAL SYSTEM WORK TO PRODUCE MOVEMENT?

The Skeletal System

The skeletal system is made up of the bones and joints and consists of 206 bones. Its functions are :

* movement* protection* support* red blood cell production* mineral storage.

The Skeletal System

BONE TYPES :

LongFlat

Irregular

ShortSesamoid(enclosed in tendon)

The Skeletal System

SkullMandibleClavicleSternumRibsHumerusUlnaRadius

Vertebrae

PelvisCarpals

MetacarpalsDigitsFemur

Patella

FibulaTibia

TarsalsMetatarsalsDigits

The Skeletal System

Curvatures of theSpinal Column Cervical (7)

Thoracic (12)

Lumbar (5)

Sacrum (5 fused)Coccyx (4 fused)

The Skeletal System

The Axial Skeleton consists of:-Skull

Sternum

Rib Cage

Vertebral Column

The Appendicular Skeleton consists of:-

Clavicle & Scapula

Arms

Pelvis

Legs

Classification of Joints

There are 3 classifications of joints: 1. Fibrous (immovable)

Skull Pelvis

Classification of Joints

2. Cartilaginous (semi-movable)

Ribs to sternum

Pubic bone

Classification of Joints

3. Synovial

(freely moveable) (controlled by muscles)

Classification of Joints

There are six different types of synovial joints:- Ball and Socket-

The ball or head of one bones inserts into the socket or cup of another.

Eg: shoulder / hip.

Hinge -

Allows movement in one plane only (flexion/extension)

Eg: elbow / knee.

Gliding –

Bones glide or slide across each other.

Eg: carpals / tarsals.

Classification of Joints

Saddle

One bone sits atop another like a saddle on a horse.

Eg: thumb

Condyloid

Bones articulate together ( butt up against each ) but without the ball and socket structure.

This allows not only flexion & extension but some circumduction – Eg: wrist

Pivot

One bone rotated around another.

Eg: atlas & axis.

All synovial joints have the same features : Hyaline Cartilage

Lines the bones / protects / reduces friction

Joint Capsule

Surrounds the joint / adds stability / stops substances entering or leaving joint

Synovial Membrane

Lines the inside of the capsule / produces & secretes synovial fluid

SYNOVIAL FLUID

Lubricates the inside of the joint

LIGAMENTS

Hold bones together / control movement

Joints

vv

Movement

FLEXION The angle between the bones

decreases. Eg: bicep curl – UP

EXTENSION The angle between the bones

increases. Eg: bicep curl – DOWN

Flexion

Extension

Movement

ABDUCTION To take away from the midline of

body

Eg: arm raise– UP

ABDUCTION ADDUCTION To bring back to the midline of

the body

Eg: arm lowered– DOWN

ADDUCTION

Movement

ROTATION Movement around an axis

Eg: turning head left & right

CIRCUMDUCTION Bone makes a cone shape as it

moves

Eg: circling the arms.

Movement

SUPINATION – Forearm is rotated to face palm UP. PRONATION – Forearm is rotated to face palm DOWN. PLANTAR FLEXION – Point toes down or raise up onto tippy toes. DORSI FLEXION – Raise toes up higher than the heels. INVERSION – Sole of the foot is turned to face inwards. EVERSION – Sole of the foot is turned to face outwards.

Revision Questions

From inferior to superior the curvatures of the spine are the:

A/ lumbar, sacral, cervical, thoracic. B/ cervical, thoracic, lumbar, sacral. C/ sacral, lumbar, thoracic, cervical. D/ thoracic, lumbar, sacral, cervical

Bones are attached to each other mainly by means of:

A/ ligaments and skin. B/ muscle and skin. C/ ligaments and muscle. D/ tendons and muscle.

A joint capsule will surround: A/ all joints. B/ synovial joints. C/ hyaline joints. D/ all of the above. E/ none of the above.

Whilst carrying a tray in front of the body with the hands lying flat under the tray:

A/ the hands are flexed. B/ the hands are extended. C/ the hands are supinated. D/ the hands are pronated.

Revision Questions

List four functions of the skeleton.movement, support, protection, production of blood cells

Name the movement for the following leg actions:-• straightening the knee to kick the ballextension• lifting the thigh straight out in front of the bodyflexion

What classification of joint is each of the following ?

Shoulder : ball and socketKnee : hingeJoints of the Skull : fibrous

Name the bones that form the following joints.Hippelvis / femurShoulderscapula / clavicle / humerus