Ch. 8 Joints Flashcards
Joints and articulations are where…
Two bones meet
Functions of joints and articulations are to…
Allow mobility
Hold bones together
Classification of joints
*SEE TABLE
See table pg. 68
Synovial Joints
Specialized Structures
Meniscus
Fibrocartlige that divides synovial cavity in two.
Functions:
Prevents side to side rocking of femur on tibia.
Absorbs shock transmitted to knee joint (padding)
Improves fit between articulating bone ends, making joint more stable and minimizing wear and tear on joint surfaces.
Synovial Joints
Specialized Structures
Bursa
Sac of synovial fluid outside of joint cavity.
Flattened fibrous sac lined with synovial membrane and containing thin film of synovial fluid.
Functions to decrease friction between adjacent structures (outside joint cavity) during joint cavity.
Locations: where ligaments. Muscles, skin, tendons, or bones rub together.
Synovial Joints
Specialized Structures
Tendon Sheath
Bursa that wraps around a tendon
Elongated bursa that wraps completely around a tendon subjected to friction.
Locations: Where several tendons are crowded together within confined spaces (wrist, shoulder, etc.)
Synovial Joints
Specialized Structures
Meniscus
Bursa
Tendon Sheath
Synovial Joints
Factors Influencing the Stability of synovial joints
Articular surfaces: shape
Number and position of ligaments: more=stronger
Muscle tone: bicep branchii
Synovial Joints
Movements allowed by synovial Joints
15 movements
- Flexion / Extension
- Abduction / Adduction
- Rotation / Circumduction
- Pronation / Supination
- Dorsiflexion / Plantar Flexion
- Inversion / Eversion
- Elevation / Depression
- Opposition
Clinical Applications
Joint Injuries
Cartilage tears
Sprains
Dislocations
Cartilage tear joint injury
(Meniscus) collagen is for strength it doesn’t stretch.
Torn Meniscus: Menisci are attached only at outer margins and are therefore frequently torn free.
Tear rarely can repair itself (remember cartilage is avascular) so treatment is usuallly to remove cartilage fragments (called loose bodies) via arthroscopic surgery to minimize interference or additional damage to the joint.
Severe impairment to joint mobility is rare but joint is definitely less stable and more likely to be damaged again.
Sprain joint injury
Ligaments reinforcing a joint are stretched or torn.
Dislocations joint injuries
When tendons or ligaments are stretched.
Bones are forced out of alignment, usually accompanied by sprains, inflammation, and difficulty in movement. Not as stable
Clinical Applications
Inflammatory and degenerative conditions
Bursitis and tendinitis
Arthritis
Lyme disease
Joint replacement
Arthritis
Over 100 different types:
All have the same initial symptoms: joint stiffness, pain, and swelling of the joint.
Chronic forms:
Osteoarthritis (degenerative joint disease): aging “wear-and-tear arthritis”
Rheumatoid arthritis:
Autoimmune: body attack’s itself thinking its foreign it has proteins on its surface. Glycoproteins IDs cell to cell recognition WBC attack, synovial joint builds up abnormal protein joints ossify due to abnormal protein levels.
Gouty arthritis (gout): Uric acid, build up breakdown of DNA/ RNA nucleuic acid -damages joints- red meat- alter diet and pain meds.
Lyme disease
Bacteria caught from a tick
Bacteria can damage joints
Joint replacement
Shaved
Plastic meniscus
Metal plate over the femur
Lab Page 56
Two opposing bones
Periosteum
Articular capsule
- Fibrous Layer
- Synovial Membrane (secretes s.f.)
Reinforcing Ligaments
Joint cavity
Articular Cartilage
Synovial FluidFibrous Joints
Sutures
Distal end of the Tibia and Fibula.
Periodontal ligament in alveolar processes (between teeth and gums)
The bones are joined by dense fibrous connective tissue and have no joint cavity present. The amount of movement allowed depends on the length of the connective tissue fibers connecting the bones.
some are slightly moveable most fibrous joints are immovable.
Cartilaginous Joints
Costal Cartilage
Intervertebral discs
Pubic symphysis
Epiphyseal plate
In cartilaginous joints, the articulating bones are connected by cartilage. Like fibrous joints, they lack a joint cavity and are not highly moveable.
Synovial Joints
Synovial Joints are those in which the articulating bones are separated by a fluid containing joint cavity. This arrangement permits substantial freedom of movement and all synovial joints are freely moveable. Nearly all joints of the limbs, and even the body, fall into this category.
General Structure pg 223
Types of synovial joints 229
Types of Synovial Joints
6 types
- Plane joints: carpals and tarsals
- Hinge joints: elbow, distal tibia, talus
- Pivot joints: C1 moving on C2 ¨rotation
- Condylar joints:metacarpophalangeal (knuckles)
- Saddle joints: carpometacarpal joint of thumb (often sprained by athletes)
- Ball and Socket joints: shoulder and hip
Support structures in synovial joints
Shoulder joint
Elbow joint
Hip joint
Knee joint
Shoulder Joint
Coracoacromial ligament
Coracohumeral ligament
Subacromial bursa
Tendon sheath of the biceps branchii tendon
Elbow Joint
Biceps branchii tendon (attaches to radial tuberosity)
Ulnar collateral ligament
Radial collateral ligament
Annular ligament (covers the head of the radius in a transverse path) wraps around
Hip Joint
Ligament of the head of the femur (fovea capitis)
iliofemoral ligament (anterior view “V” shaped)
Ischiofemoral ligament (posterior view, cut away on some lab models) posterior
Knee Joint
Anterior cruciate ligament (middle)
Posterior cruciate ligament
Lateral Meniscus
Same side as fibula
Medial Meniscus
Fibular collateral ligament
Tibial collateral ligament
Patellar ligament (attaches knee cap to tibia)
