Week 7 - Joints Flashcards
What is an articulation?
Where two or more bones connect to allow movement and stability.
What are the classification of joints?
Functional
Structural
What are the classifications to describe movement in joints?
Synarthrosis - Immovable joint, close interlocked surfaces joined with fibres, cartilage or bone.
Ampiarthrosis - slightly moveable joint, surfaces connected by collagen fibres or cartilage
Diarthrosis - Freely movable joint, synovial joint, more complex structure.
What are the types of angular movement?
Flexion
Extension
Hyperextension
Abduction
Adduction
Circumduction
Rotation
Describe angular movements in the sagittal plane
Flexion - Reducing angle
Extension - Increasing angle
Hyperextension - Extension past anatomical position
Describe angular movements in the Frontal plane
Abduction - Away from longitudinal axis
Adduction - Towards longitudinal axis
Describe Circumduction
Circular motion without rotation
Combination of flexion/extension and abduction/adduction.
Describe Rotation
Motion around longitudinal axis
Left or right rotation
Medial or lateral rotation
What are the types of rotation in the forearm?
Pronation - Radius crosses over Ulna, turns palm to face posteriorly.
Supination - to anatomical position, palms face anteriorly.
Describe movements of the foot
Inversion - Twist sole medially
Eversion - Twist sole laterally
Dorsiflexion - flexion at ankle, raise toes
Plantar flexion - Extension at ankle, pointing toes.
How are joints classified structurally?
Bony
Fibrous
Cartilaginous
Synovial
Describe bony joints
Synostosis - Synarthrosis, articulating bones fused. E.g Joint between left and right frontal bone.
Describe the different types of Fibrous joints
Suture - synarthrosis, Articulating bones interlock and attached by collagen fibres. E.g Sutures in cranium.
Gomphosis - synarthrosis, tooth fits in socket attached by ligament. E.g joints between teeth and jaws
Syndesmosis - Ampiarthrosis, bones connected by ligament. E.g Joint between tibia and fibula
Describe the different types of cartilaginous joints
Synchondrosis - Synarthrosis, bones attached by cartilage. E.g costal cartilage.
Symphysis - Ampiarthrosis, Bones separated by fibrocartilage disk. E.g Pubic symphysis.
Describe Synovial joints
Synovial - Diarthrosis, Cartilage, synovial fluid and joint capsule. E.g Typically found at ends of long bones such as the knee.
What are the features of a typical synovial joint?
Articular cartilage - smoooth covering, prevents bone touching.
Synovial fluid - High protein content (proteoglycans) Secretred by fibroblasts. Functions are lubrication, nutrient distribution and shock absorption.
Joint capsule - Fibrous connective tissue, Synovial membrane(layer of cells)
Fibrous joint Capsule
Synovial membrane
Articular cartilages
Joint cavity (containing synovial fluid)
Describe joint accessory structures and state their function
Cartilages - Cushions the joint, e.g meniscus is a fibrocartilage pad in the knee
Fat pads - Superficial, provide protection.
Ligaments - Support, strengthen joint
Tendons - Attach to muscles, help support joint
Bursae - pockets of synovial fluid, cushion where tendons or ligaments rub.
Describe Itervertebral articulations
Intervertebral discs consisting of fibrocartilage pads, annulus fibrosis(outer fibrous layer and nucleus pulposus (elastic core) are situated between Each veterbra. They are gliding joints. A slipped disc causes release of nucleus pulposus causing the disc to become distorted.
describe the structure and function of the shoulder (glenohumeral) joint
Articulating bones - Head of humerus, Glenoid cavity of scapula, Acromion, Clavivle,Coracoid process.
Glenoid labrum - Fibrocartilage ring, deepens cavity.
Ligaments
Rotator cuff muscles - tendon of supraspinatus muscle
Bursae
Function - Flexion, extension, hyperextension, abduction, adduction, rotation, circumduction
Describe the structure and function of the hip (coxal) joint
Head of femur articulates with deep acetabulum
Acetabular labrum deepens cavity
Strong joint capsule reinforced by a number of ligaments.
Fibrocartilage pad
Function - Flexion, extension, abduction, adduction, hyperextension
Describe structure and function of elbow joint
Hinge joint
Articulation - Humeroulnar, Trochlear (humerus) with Trochlear notch(ulna). Humeroradial, Capitulum (humerus) with head of radius.
Ligaments - Radial collateral ligaments, Annular ligaments.
Function - Flexion, extension
Describe structure and function of the knee joint
Complex hinge
Articulations - Two femur tibia joints, Medial and lateral condyles, medial and lateral menisci. Patella-patellar surface of femur.
Ligaments - Patellar, Anterior and posterior cruciate, tibial and fibula collateral ligaments
Bursae
Fat Pads
Function - Flexion, extension
Summarise Injuries to joints
Sprain - tearing of ligament fibers
Dislocation (luxation) - articulating surfaces displaces, damages articular cartilage,Ligaments, joint capsule.
Subluxation - Partial dislocation
Summaries Joint diseases
Osteoarthritis - used to be viewed as wear and tear, damage to articular cartilage and underlying bone, more common with age, obesity and injury. Inflammatory condition.
Rheumatoid arthritis - Autoimmune condition, inflammation of articular cartilage
Gouty arthritis - Deposition of crystals in joint as a result of metabolic disorder (gout)
