THE SKELETON

1
THE SKELETON
2
Objectives

• Identify the bones that articulate at different
  joints in the body.
• Name the 6 types of synovial joint and give
  examples of each.
• Describe the structure and function of parts of a
  synovial joint.
• Be able to classify joints according the movement
  they allow.
• Use technical language to describe common joint
  movements.
• Analyse sporting techniques in terms of joint
  movements.

3

• The human skeleton consists of 206 bones. Many of
  which move or hinge at joints. In conjunction
  with over 600 muscles these bones enable the
  human body to achieve a variety of movements.
• The functions of the skeletal system include -
• To provide a lever system against which muscles
  can pull.
• To provide a large surface area for the
  attachment of muscles.
• To protect delicate organs such as the brain.
• To give shape to the body.
• To give support to the body.
• To manufacture red blood cells and to store fat
  calcium and phosphate.
• Click here- label the skeleton and print it out
  for you file

4
AXIAL APPENDICULAR SKELETON

• The bones of the body are grouped into two major
  divisions.
• The axial skeleton consists of the bones, which
  lie around the longitudinal axis of the body.
  These include the SKULL, VERTEBRAL COLUMN,
  STERNUM RIBS.
• The appendicular skeleton consists of the bones
  of the LIMBS, PECTORAL (shoulder) GIRDLE,
  PELVIC (hips) GIRDLE.

5
JOINTS

• Joints are where two or more bones articulate
  (move).
• Joints are classified according to how much
  movement they allow.
• 1. Fibrous these are fixed or immovable joints
  such as the cranium, sacrum and the coccyx.
• 2. Cartilaginous these are slightly movable
  joints such as the vertebrae.
• 3. Synovial these are freely movable joints
  such as the shoulder and hip.

6
Fibrous Joints

• Bones are united by dense connective tissue
  consisting of collagen fibers which run between
  bones. There is NO JOINT CAVITY.
• There are three subtypes of fibrous joints
  suture, syndesmosis, gomphosis

7
Three Types of Fibrous Joints

• Suture bones are held together by a thin layer
  of dense fibrous tissue projections interlock
  bones. ONLY found in the skull.
• Syndesmosis Bones are held together by a chord
  or sheet of dense fibrous connective tissue. The
  connecting fibers holding bones together are
  long. Example thin membrane connects the
  radius and ulna
• Gomphosis It is a peg-in socket fibrous joint.
  Only examples are the teeth with the sockets in
  the mandible the thin fibrous membrane holding
  teeth inside their sockets is called the
  periodontal ligament.

8
Gomphosis Joints
Suture Joint
Syndesmosis Joint
9
Cartilaginous Joints

• Joints where the articular surfaces of the bones
  forming the joints are attached to each other by
  means of white fibrocartilaginous discs and
  ligaments
• Allows only a limited degree of movement.
• Examples cartilage between vertebrae, between the
  pubic bones, and in the sacrum

10
(No Transcript)
11
Synovial joints

• In PE these are the most important joints.
• There are 6 types of synovial joint.
• 1. Ball socket hip and shoulder.
• 2. Hinge knee, elbow and ankle.
• 3. Pivot radio-ulna, atlas/axis.
• 4. Saddle thumb.
• 5. Condyloid wrist.
• 6. Gliding between vertebrae in spine.
• Click here and complete the matching exercise

12
Ball socket joints

• The hip joint
• The head of the femur fits into a deep cavity
  called the acetabulum on the pelvic bone.
• This deep cavity gives the hip joint stability.
• The presence of strong ligaments add to the
  stability making it difficult to dislocate the
  hip.

13

• The shoulder joint
• The head of the humerus fits into a shallow
  cavity on the scapula called the glenoid fossa.
• The shoulder is the most mobile joint in the body
  but is also fairly unstable because of the
  shallow cavity.
• Stability is improved by ligaments and muscles.

14
Hinge Joints

• The knee joint
• In the knee joint the femur articulates with the
  tibia.
• The patella (knee cap) helps to give a better
  angle of pull.
• The fibula is not part of the knee joint and so
  the tibia is the weight bearing bone.

15

• The elbow joint
• In the elbow the humerus articulates with the
  radius and the ulna.
• Movement can only occur in one plane.

• The ankle joint
• In the ankle the talus articulates with the tibia
  and fibula.
• Ligaments provide stability to the joint.

16
The pivot joint

• The radio-ulna
• In this joint the radius and ulna articulate
  within the elbow joint.
• This joint allows the elbow some twisting
  movement (pronation supination.

• Atlas/axis
• In this joint the atlas and axis bones articulate
  to allow a rotation movement as in shaking your
  head.

17
Condyloid and gliding joints

• The spine
• The spine has five areas and has to fulfil many
  functions such as weight bearing stability and
  support.
• There are three type of joint in the spine but
  for A level the main one to know is the gliding
  joints between the vertebral arches.

• The wrist
• In this joint the radius and ulna bones
  articulate with 3 of the carpal bones.

What have you learnt? Click here to complete
exercise 1 Quia Click here to open word
document Complete and add to your notes
18
Saddle Joint

• This type of joint occurs when the touching
  surfaces of two bones have both concave and
  convex regions with the shapes of the two bones
  complementing one other and allowing a wide range
  of movement. The only saddle joint in the body is
  in the thumb.

19
Features of a synovial joint

• Synovial joint have a number of common features.

20
Play the matching card game to make sure you know
these features
21
Synovial Joint
22
THE SYNOVIAL JOINT
Figure 5.28
23
Knee Joint
24
Movements around a joint

• All synovial joints can move freely but the
  amount and type of movements which occur at each
  joint varies.
• Many of the movements occur in pairs they are
  the opposite of each other.
• Technical terms to describe the movements you
  need to know include-

25
(No Transcript)
26
Click on the link to complete the exercise
27
What have you learned?Click on the links to
review your learning

• Walk the plank
• Penalty shoot out
• Fling the teacher