lecture 6 - joint classifications Flashcards
What are the 3 main types of joints in the musculoskeletal system?
Fibrous joints, carilaginous joints, synovial joints
What is the tissue involved in fibrous joints?
Dense Fibrous Connective Tissue, in the form of ligaments
What is the most stable type of joint?
Fibrous joints
What are cartilaginous joints made of?
Fibrocartilage
What are synovial joints?
Joints that allow a greater range of motion, often found in the limbs
What is the range of motion at a synovial joint dependent on?
Shape of articulating bones ends, bony congruence.
What are the parts of a synovial joint?
Articular/hyaline cartilage, joint capsule, joint cavity, synovial membrane and fluid, ligaments.
What is the function of articular/hyaline cartialge at a synovial joint?
It covers the articulating ends of bones and allows them move past each other frictionlessly, as well as resisting compression, due to its high water content.
What is the synovial membrane?
A smooth and shiny membrane that lines the inner surface of the joint capsule and excretes synovial fluid.
What is the purpose of synovial fluid?
It lubricates the joint, and supplies nutrients to tissues/cartilage through joint loading.
What is the joint capsule?
A sheet of connective tissue, continuous with the periosteum, that holds the joint together. it leaves a potential space, called the joint cavity.
What are capsular ligaments?
Thickened regions of the joint capsule that provide support to the joints.
What are the collateral ligaments of the knee?
Medial Collateral ligament (MCL) and Lateral Collateral ligament (LCL)
What does the MCL of the knee connect?
The femur to the tibia
What movement does the MCL restrict?
abduction
What movment does the LCL restrict?
Adduction
What are intracapsular ligaments?
Ligaments that are seperate from the joint capsule, and found deep inside the joint.
What are the cruciate ligaments of the knee?
Anterior Cruciate Ligament (ACL) and Posterior Cruciate Ligament (PCL).
What does the ACL connect?
Anterior of tibia to posterior of femur.
What does the PCL connect?
Posterior of tibia to anterior of femur.
What movement does the ACL restrict?
Posterior displacement of femur.
What movement does the PCL restrict?
Anterior displacement of the femur.
What are the purposes fibrocartilaginous structures in synovial joints?
Additional joint structures that provide support, often by creating pads which deepen joint articulation to distribute weight and resist forces.
What are the key fibrocartilaginous structures of the knee?
The minisci (lateral miniscus and medial miniscus)
In what axis is sagittal plane movement?
Coronal axis.
In what axis is coronal plane movement?
Sagittal axis
In what axis is transverse plane movement?
Vertical axis.
What is movement in 2 axes?
biaxial
What is biaxial movement in a circle called?
Circumduction
When a joint adducts/abducts AND flexes/extends, it is said to what?
Circumduct
Plane joints are generally connecting bones with what properties?
Small bones with flat articular surfaces.
Are plane joints multiaxial or biaxial?
Multiaxial
Sliding and gliding movement is typically involved in what type of synovial joint?
Plane joints
How many (and what) axes are involved in hinge joints?
1 (uniaxial) - sagittal plane movement around the coronal axis.
What movements are involved in hinge joints?
Flexion and extension
What are examples of hinge joints?
Ankle, elbow (humerus to ulna), interphalangeal joints.
What axes are involved in pivot joints?
Transverse plane (vertical axis) - uniaxial
How can movement at pivot joints best be described?
Rotational movement
What are key examples of pivot joints?
Radioulnar joint, C1-C2 vertebrae joint (atlas and axis)
What movements are involved at condylar joints?
Flexion/extension, and rotation when flexed.
Are condylar joints biaxial or uniaxial?
Biaxial
What are key examples of condylar joints?
Knee, temperomandibular joint (TMJ)
Is the ellipsoid joint biaxial, uniaxial, or multiaxial?
Biaxial
Is there rotation at an ellipsoid joint?
No
What motion occurs at ellipsoid joints?
Circumduction (flexion/extension, abduction/adduction)
What is an example of an ellipsoid joint?
Radiocarpal joint of wrist
What motion occurs at a saddle joint?
circumduction, ‘obligatory rotation’
Is the ball + socket joint biaxial or multiaxial?
Multiaxial
What are the two examples of ball and socket joints?
Shoulder and hip joints.
What are the locations/orientations of the sagittal and coronal cranial sutures?
Sagittal runs down the centre of the skull on the sagittal plane (posterior to anterior). Coronal runs across the top of the skull, perpendicular to the midline.
What is the name for the ‘socket’ of the ball and socket shoulder joint?
Glenoid cavity
What tarsal bone articulates with the distal end of the tibia and fibula?
The talus
What is the name of the socket in which the femur articulates at the ball and socket hip joint?
Acetabulum
What is the function of the malleoli?
They prevent excessive inversion or eversion at the ankle joint
What are malleoli?
Bony projections of the tibia (medial) and fibula (lateral) that sit on each side of the ankle, preventing excessive rotation
What is the boney projection at the distal end of the fibula?
Lateral malleolus
What is the boney projection on the medial distal end of the tibia?
Medial malleolus
What is the function of the MCL and LCL of the ankle?
Resists eversion (MCL) and inversion (LCL)
What ligament connects the distal tibia and talus?
Medial Collateral Ligament (MCL)
What ligament connects the distal fibula and talus?
Lateral Collateral Ligament (LCL)
