Axial & Appendicular Skeleton

INCLUDING JOINTS

Are these anatomical positions correct?

A B

The Axial Skeleton

• Sutures: join immovable Joints

• Processes: Extending portion of the bone

• Septum: Dividing structurre

The Skull BonesThe Skull consists of

• 8 Cranial Bones – covers & protects the brain

connected by sutures

• 13 Facial Bones – encases eyes & attached to facial muscles

The Ears consists of 6 Bones

Floating in the throat is the Hyoid Bone: the only bone NOT touching another

Inner Ear

THE SKULL• Frontal: forehead under eyebrows upper

eye orbit

• Parietal: Superior & lateral

• Sphenoid:forms the base of the cranium,

behind the eye and below the front part of

the brain

• Temporal: inferior to the parietal

• Nasal Bone:Nose Bridge

• Zygomatic:Cheekbone

• Vomer:Forms the septum in the nose

• Maxilla:Upper Jaw

• Mandible:Lower jaw

• 12 pairs of RIBS

– True ribs(1-7): attach directly to

the sternum

– False ribs(8-12):Indirect or no

attachement to the sternum

– 2 floating ribs(11&12) no

attachment to the sternum

• 1 STERNUM

(breastbone)

Thoracic Cage(Rib Cage)

Vertebral ColumnThe Vertebral Column (Spinal

Column or Backbone)

– 7 Cervical (Neck) Vertebrae,

– 12 Thoracic (Chest Cavity)

– 5 Lumbar(Lower Back): support

most of the weight

– Sacrum: 5 Fused Vertebrae

(posterior wall of the pelvis)

– Coccyx: 4 Small Fused Vertebrae

Into 1 (Tail Bone)

APPENDICULAR SKELETON

Consists Of Bones Of The:

– ARMS (upper limbs)

– LEGS (lower limbs)

– SHOULDER GIRDLE (pectoral girdle)

– HIP GIRDLE (pelvic girdle)

Shoulder Girdles and Arms• Shoulder girdle is also

called the pectoral girdle

• Consists of 4 bones

• Upper limbs consist of 60

bones

• Hands and wrist

contain 54

separate

bones

Hip Girdles and Legs• Hip girdle is also called the pelvic girdle

• Consists of 2 bones

• Lower limbs consist of

60 bones

• Ankles and feet contain

52 separate bones

Joints• JOINTS: WHERE TWO Or MORE BONES

MEET

• Joints are responsible for keeping bones far enough apart so they do not rub against each other as they move, preventing damage.

• At the same time, joints hold the bones in place.

• Different joints permit different amounts of movement.

• Joints are classified by the amount and type of movement they permit.

Classification of Joints

Three Main Functional Types

• Immovable(Synarthroses) A fixed joint, one that allows no movement

• Slightly movable (Amphiarthoses)joint that permits a small amount of restricted movement

• Freely movable(Diarthoses) Permit movement in one or more directions

Classification of Joints

• Immovable

– bones of skull,

– pelvis, and sacrum

• Slightly movable

– between vertebrae,

– two bones of lower leg

Tibia and FibulaskullPelvis

Vertebra

Ribs

Freely Movable JointsTYPES OF FREELY MOVABLE JOINTS

A. BALL AND SOCKET JOINT –

Permits circular movement – the widest range of

movement.

– SHOULDER Joint- which enables you to move

your arm up, down, forward and backward, as

well as to rotate it in a complete circle.

– HIP Joint- same range of motion.

Freely Movable Joints (cont’d)

B. HINGED JOINT - Permits a

back-and-forth motion.

– The Knee- enables your leg to

flex and extend.

– The Elbow -allows you to move

your forearm forward and

backward.

– The Phalanges

Freely Movable Joints (cont’d)• C. PIVOT JOINT -

Permits rotation of one bone around another.

– The elbow enables your hand to turn over. (radiusrotates around ulna)

– It also allows you to turn yourhead from side to side.

(rotates around axis)

Freely Movable Joints (cont’d)

D. GLIDING JOINT (Plane )

Permits a sliding motion of one bone

over another.

– Found at ends of the collarbones,

– between wrist bones,

– and between anklebones.

Freely Movable Joints (cont’d)

E. SADDLE JOINT-Permits movement in two planes.

– This type of joint is found at the base of the thumb

Anatomy of a JointStructures of a freely movable joint

• 2 or more bones

• Cartilage

• Joint capsule

• Synovial membrane

• Synovial fluid

• Fat

• Bursa

• Meniscus

• Ligaments

• Tendons

• Cartilage - at the joint, the

bones are covered with

cartilage, which is wear-

resistant and helps reduce

the friction of movement.

• Joint capsule- is a thick,

tough layer that envelops

the joint cavity forming a

membrane or sac that

adheres firmly to the

periosteum of the

articulating bones

Anatomy of a Joint

Anatomy of a Joint• Synovial membrane -

a tissue that lines the

joint and seals it into a

joint capsule. The

synovial membrane

secretes synovial fluid.

• Synovial fluid - a

clear, sticky fluid

secreted by the

synovial membrane to

lubricate the joint.

Anatomy of a Joint• Fat- Helps pad and cushion

the joint.

• Bursa- fluid-filled sac between adjacent structures such as ligaments or bones which help reduce friction in a joint, cushion it, and absorb shock.

• Meniscus- wedge shaped cartilage, curved like the letter "C" at the inside and outside of each knee. A strong stabilizing tissue, helps the knee joint carry weight, and glide and turn in many directions. It also keeps your femur and tibia from grinding against each other.

Anatomy of a Joint• ligaments - tough, elastic

bands of connective tissue

– surround the joint to give

support and limit the

joint's movement.

– Attach bone to bone

• tendons – another type of

tough connective tissue

– on each side of a joint

attached to muscles that

control movement of the

joint.

– Attach muscle to bone

Knee

Joint