Lecture 6: Joint Classification (Joint II) Flashcards
What is a fibrous joint?
Tissue: DFCT
Structure: ligament
Function: limited movement/stability
What is a cartilaginous joint?
Tissue: fibrocartilage
Structure and functions: various structure and special functions (some movement)
What is a synovial joint?
• Free moving
• Most limb joonts
- Amount of movement and direction is determined by structure
What are some features of a synovial joint?
• Compression association o tissues and structures
• Facilitation of free movement and control of movement
• Bone ends determine the range of motion at a joint
• Bony congruency
What does the structure of a synovial joint consist of?
• Bone ends
• Articular cartilage
• Joint capsule
• Joint cavity (potential space)
• Synovial membrane
• Ligaments
- Structure = function (= movement)
What is the purpose of hyaline (articular) cartilage in a synovial joint?
To cover bone ends where they articulate (subchrondral bone), allowing fir smooth and frictionless movement
What does a joint capsule consist of?
• Outer layer is made if DFCT
• Inner layer of synovial membrane
What is the purpose or a joint capsule?
• To hole bones together
• To be tight and thick where more support is required
• Loose where movement is allowed
What is a capsular ligament?
In some joints, thickenings of capsules are present where more support is required.
E.g. Collateral ligaments of knee
Medial collateral ligament (MCL)
• connects femur to tibia
• restricts abduction
Lateral collateral ligament (LCL)
• connects femur to fibula
• restricts adduction
What is an intracapsular ligament?
In some joints, additional bands of DFCT located internally to the capsule hold bones together (restricts movement between bones).
E.g. Cruciate ligaments of knee
• Arise from tibia and insert into femur
Anterior cruciate ligament (ACL)
• Anterior of tibia to posterior of femur
• Restricts posterior displacement of femur
Posterior cruciate ligament (PCL)
• Posterior of tibia to anterior of femur
• Restricts anterior displacement of femur
What are fibrocartilaginous pads/structures?
In some joints, small strctures made if fibrocartilage fill in space providing cushioning/shock absorption and/or deep articulations.
E.g. Mensci (pl.)/meniscus (sing.) in thr knee
• Half-moon shaped structure that sit between femur and tibia
How much movement is possible at a joint?
Range of movement (ROM)
• the type and amount of movement is determined by the structure of the joint
ROM is determine by
• Bone-end shape
• Ligament location and length
• Body surface contact
