Bones and Joints Flashcards
What are the classifications of bones by shape?
Flat Short Long Irregular Sesamoid Sutural
Give an example of a short bone
Carpal
Give an example of an irregular bone
Vertebra
Where do you find sutural bones?
Within a cranial suture
Short bones consist mainly of …
Spongy bone
Where does a nutrient artery enter the bone?
Diaphysis
What are the structural classification of joints?
Fibrous
Cartilaginous
Synovial
What are the functional classifications of joints?
Synarthrosis
Amphiarthrosis
Diarthrosis
What do we term an immovable joint?
Synarthrosis
What do we term a freely moveable joint?
Diarthrosis
Define syndesmosis
Slightly moveable fibrous joint which connects bones via connective tissue
What is another name for a primary cartilaginous joint and what are its features?
Synchondrosis
Connective medium is hyaline cartilage
Synarthrosis
Give an example of a primary cartilaginous joint
Xiphisternal joint
What is another name for a secondary cartilaginous joint and what are its features?
Symphysis
Connective medium is fibrocartilage
Amphiarthrosis
Give an example of a secondary cartilaginous joint
Pubic symphysis
What is the fibrous capsule of a synovial joint made from?
Collagen
What are the features of synovial membrane?
Thin
Highly vascularised
Produces synovial fluid
What is a tendon sheath?
An elongated bursa wrapped around a tendon
Name some features of synovial fluid
Clear/pale yellow
Viscous
Slightly alkaline at rest
Only a small volume in joint spaces
What are the functions of synovial fluid?
Reduces friction
Shock absorption
Nutrient and waste transport
Does articular cartilage have a blood supply?
No
Articular cartilage is avascular so is dependent on diffusion through the synovial fluid.
What is Hilton’s law?
The nerves supplying the joint also supply the muscles moving the joint and the skin overlying the insertions of these muscles.
What are the types of synovial joint?
Planar Hinge Pivot Condyloid Saddle Ball and socket
Describe a planar joint
Articulating surfaces are flat or only slightly curved
Gliding/sliding movements
Non-axial
Give an example of a planar joint
Sternoclavicular
Describe a hinge joint
Pulley shaped: convex surface of one bone fits into the concave surface of another
Uniaxial
Give 2 examples of hinge joints
Knee
Ankle
Describe a pivot joint
Rounded/pointed surface of one bone articulates within a ring formed by another bone
Uniaxial
Give an example of a pivot joint
Atlantoaxial
Describe a condyloid joint
Oval shaped condyle of one bone rests on elliptical cavity of another
Biaxial
Give an example of a condyloid bone
Metacarpophalangeal joint
Radio-carpal (wrist)
Describe a saddle joint
One bone is saddle shaped and the other bone resembles the legs of the rider
Biaxial
Give an example of a saddle joint
1st carpometacarpal joint (thumb)
Describe a ball and socket joint
Ball like surface of one bone fits into the cup like surface of another
Polyaxial
Give 2 examples of ball and socket joints
Hip
Shoulder
What factors affect stability and motion of joints?
Structure/shape of articulating bones Strength and tension of joint ligaments Arrangement and tone of muscles Neighbouring soft tissues Hormones Use/disuse
What are the effects of ageing on joints?
Decreased production of synovial fluid
Thinning of articular cartilage
Shortening of ligaments
Degenerative changes
What are the symptoms of arthritis?
Pain, swelling and stiffness
What are the signs of arthritis?
Redness, swelling, deformity, tenderness, reduced range of movement and abnormal gait
What are the x-ray features of rheumatoid arthritis?
Narrowing of joint space Loss of bone matrix Bony erosions Subluxation Gross deformity
What are the functions of the skeleton?
Support Protection Movement Mineral and growth factor storage Haematopoeisis
What is the most commonly dislocated joint?
Shoulder (glenohumeral)
