Chapter 9: 9.4 Synovial Joints

these are the most moveable joints of the body

Synovial joints

layer of the articular capsule that is compose of dense irregular connective tissue that is continuous with the periosteum of joining bones

fibrous layer

what function does the synovial layer of the articular capsule of synovial joint cavities serve

functions to make synovial fluid

synovial joints are richly supplied with sensory nerve fibers that innervate the articular capsule, some of these fibers detect pain, but most monitor

how much the capsule is being stretched

type of reinforcement ligament that is internal to the capsule

intracapsular reinforcement ligament *anterior and posterior cruciate ligaments

a feature unique to synovial joints, this a space that holds small amounts of synovial fluid

joint cavity

synovial joints have the following features (6)

1. articular cartilage 2. joint cavity 3. articular capsule 4. synovial fluid 5. reinforcing ligaments 6. nerves and vessel

what are the 3 types of reinforcement ligaments found in some synovial joints

1. capsular 2. extracapsular 3. intracapsular

what are the 2 layers that compose the articular capsule of synovial joint cavities

1. fibrous layer 2. synovial membrane

what are the 2 main functions of articular disc/meniscus

1. fills gaps and improves fit, distributing load more evenly and minimizing wear/damage 2.may allow two different movements at the same joint

several nerves and blood vessels supply overlapping areas of the joint capsule in different directions, why is this

overlap provides redundancy, if the joint is compressed or injured in one area, other areas stay viable to continue nourishing and maintaining the joint

by monitoring the stretching of the capsule, the body is able to sense

posture and body movements

some synovial joints are strengthened by

reinforcement ligaments

what function does the fibrous layer of the articular capsule of synovial joint cavities serve

strengthens the joint; so that bones are not pulled apart

besides the joint cavity, synovial fluid can also be found here as well

within articular cartilage

synovial joint cavities are enclosed by a two-layered ...

articular capsule

how does an articular disc differ from articular cartilage

articular disc is composed of fibrocartilage an is located within the joint cavity articular cartilage is composed of hyaline cartilage and covers the adjoining surfaces of all synovial joints

present in some synovial joint cavities, is a disc that extends internally from the capsule and completely or partly divides the joint cavity in two

articular disc/meniscus

these often occur in joints whose articulating bone ends have somewhat different shapes

articular disc/meniscus

bursa and tendon sheaths are often referred to as ___________ ___________, reducing friction between body elements that move over one another

ball bearings

structure associated with synovial joints that occurs where ligaments, muscles, skin, tendons or bones overlie each other and rub together

bursa

type of reinforcement ligament that thicken parts of the fibrous layer of the articular capsule

capsular reinforcement ligament

why is weeping lubrication important to articular cartilage

cartilage is avascular, hence this is the main way these cells receive nutrition

All synovial joints fall under this functional joint type

diarthroses

type of reinforcement ligament that is located just outside of the capsule

extracapsular reinforcement ligament *fibular and tibial collateral ligaments

bursa and tendon sheaths both contain

synovial fluid

extensive capillaries in the synovial membranes produce the blood filtrate that is the basis of the ...

synovial fluid

viscous liquid inside synovial joint cavities that lubricates the joint surface ad nourishes the articular cartilages

synovial fluid

blood vessels supplying synovial joints can be found here

synovial membrane

layer of the articular capsule that is composed of loose connective tissue and covers all internal joint surfaces not covered by cartilage

synovial membrane

structure that is essentially an elongated bursa that wraps around tendons and occurs only on tendons that are subjected to friction

tendon sheath

mechanism that nourishes the cells of the articular cartilage via pressure placed on the joint during normal movement, causing squeezing of synovial fluid into and out of the articular cartilage

weeping lubrication

this also allows adjoining bones to move across each other with minimal friction

weeping lubrication