Joints - Anatomy Flashcards
What are the 2 classes of joints?
Synarthroses
Diarthroses
Do synarthroses allow movement?
They allow no/very limited movement
2 classes of synarthroses
Fibrous joint
Cartilaginous joint
Types of synovial joints (6)
Ball-and-socket Hinge joint Planar joint Pivot joint Saddle joint Condyloid joint
Degrees of Freedom for hinge joint
1
Movement allowed in a hinge joint
Flexion-Extension
Examples of hinge joints in the body
Ulno-humeral (elbow)
Interphalangeal joints
Knee and ankle are atypical hinge joints
Degrees of freedom for pivot joint
1
Movement allowed by a pivot joint
Rotation
Examples of pivot joints in the body
Radio-ulnar joint (allows supnation/pronation or forearm)
Atlanto-axial joint (allows head to turn left/right)
Degrees of freedom for a condyloid joint
2
Movement allowed by condyloid joint
Flexion-Extension
Abduction & Adduction
Examples of condyloid joints in the body
Radio-carpal
1st-4th MCP
Degrees of freedom for a ball-and-socket joint
3 (allows movement in all 3 planes)
Movement allowed by a ball-and-socket joint
Flexion-Extension
Abduction & Adduction
Internal & External rotation
Examples of ball-and-socket joints in the body
Gleno-humeral joint
Acetabulo-femoral joint
Degrees of freedom for a plane joint
variable (translational)
Movement allowed by a plane joint
Sliding and/or rotation
Examples of plane joints in the body
Inter-carpal joints
Inter-tarsal joints
Sacro-iliac joint
Degrees of freedom for a saddle joint
2
Movement allowed for a saddle joint
Flexion-Extension
Abduction-Extension
Examples of saddle joints in the body
1st CMC (base of thumb) Sterno-clavicular joint
What are the 2 layers of the synovial membrane
Intimal
Subintimal
Describe the make-up of the intimal layer of the synovial membrane (2)
Contains fibroblasts (secrete lubricin) Contains phagocytic macrophages
Describe the make-up of the subintimal layer of the synovial membrane
Contains: Blood vessels Lymphatics Type 1 collagen Subintimal fibroblasts & macrophages
What can we attribute the viscosity of synovial fluid to?
Hyaluronate
Synovial membrane function (3)
Produce synovial fluid
Maintain synovial fluid volume
Providing a packing that can change shape in whatever way is needed
Function of synovial fluid (4)
Shock absorber
Provide nutrients for cartilage
Remove waste from cartilage
Provides lubrication
Joint functions (2)
Provide low-friction surface for motion
Transfer loads
Examples of fibrous synarthroses in the body
Tibio-talar joint
Sutures in skill
Examples of cartilaginous synarthroses in the body
Pubic symphysis
Costochondral joints (completely immovable)
Intervertebral discs
