Chapter 9-11 A & P
Structure of Synovial (Diarthrosis) Joint
*Look at index #4
Most of Chapter 10 on Note Cards!
*Look at index, starts from #11!
Notes
-700 muscles -when contract alway peaks -increase number of myofibrils -ligament: bone crossing to bone -tendons: muscle to bone
Articulations (Joints)
-Joint Classification -Structure of Synovial Joints -Types of Synovial Joints -Movements at Synovial Joints
Synovial/ Diarthrosis Joints:
-Structure (ex. proximal interphalangeal joint- 2nd finger- PIPJ, MIPJ, DIPJ) -Subtypes -Movements *Look on index #1
Anatomy- Macroscopic/ microscopic view
-Whole muscle -Bundles (fascicles) -Cells (muscle fibers; myofibers) -Myofibrils (organelles) -Sarcomeres (compartments) -Filaments -Protein molecules
6) Ball & Socket Joint
-ball/ socket surface -triaxial (all motion): most mobile joints, combine angular movement & rotation ex. hip joint, shoulder joint *Look at index #10
2) Hinge Joints
-convex/ concave surface -monaxial: opening or closing motion -one direction on axis ex. elbow, knee, ankle, and interphalangeal joint *Look at index #6
Pollicis Brevis Muscle
-located at the skull -size: small -action: abducts -found in february 1995 -named in march 1996: sphenomandibularis officially added the 40th edition of Gray's Anatomy Nov. 2008 -where headaches form -problems with mandible
4) Ellipsoid (condylar) Joint
-oval surface or oval depressed surface -biaxial -side-to-side motion -up & down motion -flexion & extension -abduction: away -adduction: toward ex. radiocarpal, metacarpophalangeal (joints 2-5), and wrist articulates with radius *Look at index #8
3) Pivot Joint
-pointed or circular surface -monaxial (rotation) ex. C1 and C2 articulate with each other (rotate) *Look at index #7
Synovial Membrane
-produces a synovial fluid which fills the joint cavity -fluid is clear like the clear part of a cracked egg
5) Saddle (sellaris) Joints
-saddle surface -biaxial movement: along 2 axes -side-to-side movement -up & down movement ex. trapezium articulates with 1st metacarpal (opposite side of thumb), gasp & manipulate things *Look at index #9
1) Gliding (plane) Joints
-surfaces are flat or slightly curved -sliding movements (nonaxial/ multiaxial): ex. intercarpal, intertarsal, sacro-iilac, and acromioclavicular joint *Look at index #5
Naming Skeletal Muscles
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Additional Structures
1) Accessory ligaments (cruciate ligaments): -more ligaments needed -hold bones together -some are found inside the joint called intracapsular ligament (ACL) -some are found outside the joint (bands) of connective tissue called extracapsular ligament
Group Actions of Skeletal Muscles
1) Agonist (prime mover) -causes desired action (contracts) ex. drinking coffee, biceps brachii 2) Antagonist -relaxes (lengthens) ex. drinking coffee, triceps brachii 3) Synergist -steady at movement -prevent unwanted movement -help agonist work better -located along side agonist 4) Fixator (s) -stabilize the origin of the prime mover -increase efficiency of prime mover
Each muscle has a beginning and an end:
1) Origin- at the beginning, and is stable, does not move 2) Insertion- movement is found
Functions of Skeletal Muscles
1) Produce skeletal movement (joints): -contract tissues: isotonic ("same" "tension"): motion (movement) ex. writing 2) Maintain posture & body position: -contract: isometric ("same" "measure"): stabilization (no movement) 3) Protects underlying organs 4) Guards entrances/ exits- forms sphincters (opens & closes) 5) Maintain body temp. (thermogenesis): -responsible for 85% body heat 6) Store nutrient reserves: -amino acids, calcium, protein, etc.
Muscle Tissue
1) Skeletal -bones (origin/ insertion) -voluntary -moves bones/ joints 2) Cardiac -heart (myocardium- wall of heart) -involuntary (autorhythmicity) -moves blood 3) Smooth -internal organs (wall of organs) -involuntary -moves internal substances (water, food, waste)
Skeletal Muscles
1) Strength- increase myofibrils (gives diameter/ strength) 2) Recuit more cells (activate large motor unit)
Movements at Synovial Joints
1) gliding 2) hinge joint 3) pivot joint 4) ellipsoid (condylar) joint 5) saddle (sellaris) joint 6) ball & socket joint
Joint Classification
2 Methods: 1) Structural Classification- based on their anatomical characteristics. 2) Functional Classification
Additional Structures
2) Articular discs (menisci- extra pieces): -inside the space -fibrocartilage -inside joint cavity -better fit: wedged inside a space to make bones fit together
Additional Structures
3) Bursae- filled with synovial fluid -sacs or compartments around the joint: not inside -cushion & protect joint -found outside of joint
Skeletal Muscles
Attach to bones using: 1) Tendon -cord like structure 2) aponeurosis -a sheet like structure (connective tissue, around the abdominal area)
Structural Classification
Based on their anatomical characteristics: 1) Structural -no joint cavity -fibrous tissue between bones ex. located only between the bones of the skull 2) Cartilaginous -no joint cavity -cartilage between bones ex. synchondrosis- (together + chondros, cartilage) cartilaginous bridge between two articulating bones 3) Synovial -joint cavity filled with fluid -surrounded by connected tissue
Functional Classification
Based on type of movement they permit: 1) Synarthrosis -immovable joint 2) Amphiarthrosis -slightly movable joint 3) Diarthrosis -freely moveable joint ex. knee joint
6 Subtypes of Synovial/ Diarthrosis Joints:
Classification is based on: -the shape of articulating surfaces -the type of movement allowed -nonaxial (small/ no movement) -monaxial (1 direction): on axis, rotation -biaxial (2 different directions): on axis -triaxial (3 different directions): on axis -multiaxial (any direction)
Structure of Synovial (Diarthrosis) Joint:
Functions: -lubrication -nutrition: nourishes the cartilage -shock absorption -antimicrobial: joints are sterile but can kill any germs: protect from infections *Look at index #2
Structure of Synovial (Diarthrosis) Joint:
Functions: -wt. bearing joints -frequently used joints -aging disease due to using and wearing down cartilage (usually middle age & elderly at risk) ex. hip is a wt. bearing joint -creapitis: audible sound or grinding of bones: you will never grow cartilage back -hip replacement: needed if the cartilage is damaged ex. new hip joint is replaced *Look at index #3
Biggest Muscle?
Gluteus Maximus
Chapter 9
Joints
Widest Muscle?
Latissimus dorsi
Arthroscopy
MIS- minimally invasive surgical procedure
Strongest Muscle?
Masseter
Chapter 10
Muscle Tissue
Longest Muscle?
Sartorius
Chapter 11
Skeletal Muscle
Combining the 2 Classifications:
Structural + Functional 1) Fibrous + Synarthrosis= Joint Suture 2) Cartilaginous + Synarthrosis= Synchondrosis ex. first rib attached to sternum- does not move 3) Fibrous + Amphiathrosis= Syndesmosis ex. distal end of tibia articulating with distal end of fibula (interosseous membrane= in between joints) theses are generally: -strong stable joints -dislocation (very rare) -not a lot of diseases in these joints found in axial skeleton 4) Cartilaginous + Amphiarthrosis= Symphysis ex. pubic symphysis (no movement)
Combining the 2 Classifications:
Structural = Functional Synovial (joint cavity) = Diarthrosis (freely moveable) -these joints tend to be weaker -weak joints -more dislocations (luxations; subluxation) -more disease (ex. arthritis & gout) -found in appendicular skeleton
Extra Ligament
after ACL joint injury, the knee becomes unstable: the tibia & femur separated (reinforced)
Collateral Ligaments
around ankle & knee
Osteoarthritis (OA)
articular cartilage worn away joint space: uneven; narrow bone to bone
Capsule Ligaments
holds bones in proper alignment
Bursitis
inflamed sacs ex. bunions: bone of big toe
Nonaxial
joints that permit gliding, allow only small amounts of movement and permit small gliding movements or restrict movement
Articular Cartilage
makes joint smoother
Ligament
moves from bone to bone to another cavity
Sprain
partial tear of ligament, bone are not held together or aligned correctly, and joints are unstable
Monaxial Articulation
permits movement along only one axis, angular movement in a single plane
Hypothermia
shivering increases body heats
Rheumatology
the study of joint disease
Arthrology
the study of joints
