Joints Flashcards
Define joint, what are two types
two skeletal elements come together; synovial and solid
Synovial Joint
skeletal elements are separated by a narrow articular cavity (cavity looks larger because cartilage doesn’t attenuate X-rays as well as bone)
What are the three features of a synovial joint?
1) hyaline cartilage
2) inner synovial membrane
3) outer fibrous membrane
Outer fibrous membrane
dense connective tissue that surrounds and stabilizes the joint; can thicken to form ligaments
Inner Synovial Membrane
encloses the joint cavity at the margins of the joint surfaces at the interface b/w cartilage and bone; very vascular and produces synovial fluid which is a lubricant for the joint
Hyaline Cartilage
covers articulating surfaces of skeletal elements
What are synovial bursae?
closed sac of synovial membrane that occur b/w structures to reduce friction
Where do we find synovial bursae?
tendon/bone; tendon/joint; skin/bone
What is a tendon sheath?
a closed sac of synovial membrane that covers a tendon to reduce friction
We classify joints by ______ and _______.
Shape; movement
What are the seven shapes of synovial joints?
- plane (flat)
- hinge
- pivot
- bicondylar
- condylar (ellipsoid)
- saddle
- ball and socket
What are the three types of movement of synovial joints?
- uniaxial (UA) - moves in one direction (x, y, or z)
- biaxial (BA) - moves in two directions (xy, yz, or xz)
- multiaxial (MA) - moves in all directions
Describe and provide an example of a plane joint.
UA - sliding/gliding when a bone moves across another
i.e. acromioclavicular joint (scapula glides past clavicle when raising and rotating arm)
Describe and provide an example of a hinge joint.
UA - allows movement along 1 axis and the direction is transverse
i.e. humero-ulnar (elbow) joint (allows for flexion and extension)
Describe and provide an example of a pivot joint.
UA - allows movement along axis that is longitudinal to the shaft of the bone
i.e. atlanto-axial joint. (in neck, allows you to turn head left and right)