Anatomy & Physiology Chapter 9 Joints PDF

ANATOMY & PHYSIOLOGY Chapter 9 JOINTS PowerPoint Image Slideshow FIGURE 9.1 Girl Kayaking Without joints, body movements would be impossible. (credit: Graham Richardson/flickr.com) CLASSIFICATION OF JOINTS Joint (articulation) – where adjacent bones or bone and cartilage come togeth...

ANATOMY & PHYSIOLOGY Chapter 9 JOINTS PowerPoint Image Slideshow FIGURE 9.1 Girl Kayaking Without joints, body movements would be impossible. (credit: Graham Richardson/flickr.com) CLASSIFICATION OF JOINTS Joint (articulation) – where adjacent bones or bone and cartilage come together Classified by structure and function Structural – based on whether the articulating surfaces are connected by fibrous connective tissue or cartilage, or whether they contact each other within a fluid-filled cavity Fibrous Cartilaginous Synovial CLASSIFICATION OF JOINTS Functional – Synarthrosis – immobile or nearly immobile (sutures), strong union between bones Amphiarthrosis – limited mobility (adjacent vertebrae and pubic symphysis) Cartilaginous joints Diarthrosis – freely mobile, all synovial joints Uniaxial – allows motion for a single plane (elbow) Biaxial – motion within two planes (metacarpophalangeal joint, knuckle) Multiaxial – several directions (shoulder, hip) FIBROUS JOINTS Ligament – narrow band of fibrous connective tissue Suture – mostly immobile joints in skull Very strong for protecting brain and face Fontanelle – areas where connective tissue is much wider Provide flexibility to skull during birth Synostosis – connective tissue is ossified FIBROUS JOINTS Syndesmosis – two parallel bones united by fibrous connective tissue Gap may be narrow – joined by ligaments Gap may be wide – interosseous membrane Greatly limits movement but does allow some Provide areas for muscle attachment in leg and forearm FIBROUS JOINTS Gomphosis – anchors root of tooth to bony socket Periodontal ligament – numerous short bands of dense connective tissue Completely immobile CARTILAGINOUS JOINTS Synchondrosis – bones joined by hyaline cartilage (ribs to vertebrae) Temporary – epiphyseal plate Permanent – uniting ribs to sternum No movement between bone and cartilage SYNOVIAL JOINTS Most common type of joint Fluid-filled joint cavity Increased mobility Articular capsule – fibrous connective tissue structure that is attached to each bone just outside of the bone’s articulating surface Bones of the joint articulate with each other within the joint cavity Articular cartilage – prevents friction, thin layer of hyaline cartilage covering entire articulating surface of each bone Cartilages of each bone not continuous with each other – acts like “Teflon” SYNOVIAL JOINTS Synovial Membrane – lining inside of articular capsule and secrete synovial fluid Thick and slimy, lubrication for reducing friction Outside of articulating surfaces bones connected by ligaments – strong bands fibrous connective tissue Strengthen and support joint, limit to normal motions Extrinsic ligament – outside capsule Intrinsic ligament – incorporated into the wall of capsule Intracapsular ligament – inside capsule Tendon – connective tissue attaching muscle to bone Provides additional support SYNOVIAL JOINTS Articular disc – found in a few, between articulating bones Articular disc – small and oval Meniscus – larger and c-shaped Strengthen joint (sternoclavicular joint) Shock absorption and cushioning (knee) Smooth movements (temporomandibular joint) Bursa – thin connective tissue sac filled with lubricating fluid, reduce friction by separating adjacent structures Subcutaneous – between skin and bone Submuscular – between muscle and bone Subtendinous – between tendon and bone TYPES OF SYNOVIAL JOINTS Pivot joint – rounded portion of a bone is enclosed within a ring formed partially by the articulation with another bone and partially by a ligament Bone rotates within ring Uniaxial diarthrosis Atlantoaxial – between atlas and axis Proximal radioulnar joint – radius and ulna TYPES OF SYNOVIAL JOINTS Hinge joint – convex end of one bone articulates with the concave end of adjoining bone Bending and straightening along single axis Knee, ankle, elbow, interphalangeal joints TYPES OF SYNOVIAL JOINTS Condyloid Joint – shallow depression at the end of one bone articulates with a rounded structure from adjacent bone Knuckle joints, radiocarpal joint Biaxial Bending and straightening Side to side movement TYPES OF SYNOVIAL JOINTS Saddle Joint – both articulating surfaces have a saddle shape – concave in one direction and convex in the other Two bones fit together like rider on a saddle Biaxial Carpometacarpal (thumb) TYPES OF SYNOVIAL JOINTS Plane joint – articulating surfaces are flat or slightly curved and about same size, bones slide against each other Motion is small and tightly constrained Multiaxial Between carpal bones, tarsal bones TYPES OF SYNOVIAL JOINTS Ball and socket – greatest range of motion Rounded head of one bone fits into concave articulation of another Hip and shoulder multiaxial TYPES OF BODY MOVEMENTS Flexion and Extension – movements within sagittal plane and involve anterior or posterior movements of body or limbs Lateral flexion – bending of neck toward right or left side In limbs – flexion decreases angle between bones Extension – increases angle – straightening joint TYPES OF BODY MOVEMENTS Hyperextension – extension beyond normal range Hyperflexion – excessive flexion TYPES OF BODY MOVEMENTS Abduction and adduction – within coronal plane and involve medial-lateral motions of limbs Abduction – moves limb away from midline of body Raising arm at shoulder joint Adduction – moves limb toward body Bring arm back down TYPES OF BODY MOVEMENTS Circumduction – movement of a body region in a circular manner One end of the body region being moved stays relatively stationary while the other end describes a circle Saddle joints, ball-and-socket joints TYPES OF BODY MOVEMENTS Rotation – within the vertebral column, at a pivot joint, or ball- and-socket joint Twisting movement One bone rotates in relation to another bone Medial rotation – brings anterior surface of limb toward midline Lateral rotation – anterior surface moves away from midline TYPES OF BODY MOVEMENTS Supinated position – upper limb held next to body with palm facing forward Pronated position – when palm faces backward Supination – moves palm to supinated position Pronation – moves palm to pronated position  TYPES OF BODY MOVEMENTS Dorsiflexion and Plantar flexion – movements at ankle joint Dorsiflexion – lifting front of foot so that the top of the foot moves toward anterior leg Plantar flexion – lifting heel and pointing toe downward  TYPES OF BODY MOVEMENTS Inversion – turning of foot to angle the bottom of the foot toward the midline Eversion – turns bottom of foot away from midline Take place among tarsal bones (intertarsal joints)  TYPES OF BODY MOVEMENTS Protraction and Retraction – movements of scapula or mandible Protraction – shoulder is moved forward, like throwing a ball Retraction – scapula being pulled toward vertebral column  TYPES OF BODY MOVEMENTS Depression and Elevation – downward and upward movements of the scapula or mandible Elevation – upward movement Depression – downward movement  TYPES OF BODY MOVEMENTS Excursion – side-to-side movement of mandible Lateral – moves mandible left or right – away from midline Medial – moves toward midline  TYPES OF BODY MOVEMENTS Superior and inferior rotation – movements of the scapula, defined by the direction of movement of the glenoid cavity Superior – glenoid cavity moves upward as medial end of scapular spine moves downward – contributes to abduction Inferior – during limb adduction, downward motion of glenoid cavity and upward movement of medial end of scapular spine TYPES OF BODY MOVEMENTS  TYPES OF BODY MOVEMENTS Opposition – thumb movement that brings tip of thum in contact with tip of finger First carpometacarpal joint Reposition – returning thumb to anatomical position PRACTICE – IT HELPS TO STAND UP AND DO THE MOTIONS Flexion and extension Abduction and adduction Circumduction Rotation Supination and pronation Dorsiflexion and Plantar flexion Inversion and eversion Protraction and retraction Depression and elevation Superior and inferior rotation Opposition and reposition  VERTEBRAL COLUMN Vertebrae articulate with each other at synovial joints between the superior and inferior articular processes – zygapophyseal joints Plane joints providing limited motion Orientation of articular processes determines types of motion available Cervical and lumbar regions have greatest range of motion  VERTEBRAL COLUMN Atlanto-occipital joint – articulations between superior articular processes of the atlas and the occipital condyles on the base of the skull Allows skull to rock back and forth, flexion and extension of head  VERTEBRAL COLUMN Atlantoaxial joint – between atlas and axis, consists of three articulations Allows head to move left and right  TEMPOROMANDIBULAR JOINT TMJ – allows for opening (mandibular depression) and closing (mandibular elevation) and side-to side protraction/retraction motions of lower jaw Articulation between mandibular fossa and articular tubercle of temporal bone, with the condyle of the mandible Filling gap between skull and mandible is a flexible articular disk – smooth movements  SHOULDER JOINT Glenohumeral joint – ball-and-socket formed by articulation between head of humerus and glenoid cavity of scapula Largest range of motion of any in body Lack of structural support and stability  SHOULDER JOINT Glenoid labrum – small lip of fibrocartilage deepening glenoid cavity Coracohumeral ligament – weak intrinsic ligament, thickening of articular capsule Glenohumeral ligaments (3) – strengthen capsule walls  SHOULDER JOINT Rotator Cuff – four muscles arise from scapula and attach to greater or lesser tubercles of humerus, cross the shoulder joint, tendons encircle the head of humerus Thickening of capsule by these four tendons  SHOULDER JOINT Subacromial bursa and Subscapular bursa – help prevent friction between rotator cuff muscle tendons and the scapula Rotator cuff muscles hold head of humerus in position SHOULDER JOINT  ELBOW JOINT Humeroulnar joint – uniaxial hinge, articulation between trochlea of humerus and trochlear notch of ulna Humeroradial joint and proximal radioulnar joint also associated with elbow joint All three enclosed within a single articular capsule  ELBOW JOINT Articular capsule thickened along outside margins by strong intrinsic ligaments – prevent side-to-side movements and hyper extension Ulnar collateral ligament – medial side, from medial epicondyle of humerus to medial side of proximal ulna Resists hyperextension Tommy John surgery  ELBOW JOINT Radial collateral ligament – lateral side of elbow, from lateral epicondyle of humerus to lateral side of annular ligament Annular ligament – encircles head of radius Articulates with radial notch of ulna at proximal radioulnar joint Allows for rotation of radius during supination and pronation of forearm ELBOW JOINT  HIP JOINT Multiaxial ball-and-socket joint between head of femur and acetabulum of hip bone Carries weight of body – requires strength and stability – smaller range of motion than shoulder Acetabulum – socket portion of hip joint, deep with large articulation area for femur Acetabular labrum – fibrocartilage lip attached to outer margin of acetabulum, deepens acetabulum  HIP JOINT Three intrinsic ligaments: Iliofemoral, pubofemoral, ischiofemoral Spiral around head and neck of femur Pull head of femur tightly into acetabulum when standing  HIP JOINT Ligament of the head of the femur – inside articular capsule Spans between acetabulum and femoral head Not for support but pathway for artery to femoral head  KNEE JOINT Largest joint of body – three articulations: Femoropatellar joint, medial tibiofemoral joint, lateral tibiofemoral joint All enclosed within single articular capsule Hinge joint – rolling and gliding motions of femur on tibia Weight bearing  KNEE JOINT Femoropatellar joint – patella slides vertically within a groove on the distal femur Sesamoid bone incorporated into tendon of quads Patellar ligament – from patella to anterior tibia just below knee  KNEE JOINT Articular discs – C-shaped fibrocartilage attached to tibial condyles Padding between bones Lateral meniscus Medial meniscus – less movement – anchored at outer margin to articular capsule  KNEE JOINT Extrinsic ligaments – outside articular capsule Provide support – mainly in extended position Fibular collateral ligament – lateral side, from lateral epicondyle of femur to head of fibula Tibial collateral ligament – from medial epicondyle of femur to medial tibia  KNEE JOINT intrinsic ligaments – inside articular capsule Resist knee hyper extension Anchored inferiorly to tibia at intercondylar eminence – roughened area between tibial condyles Run diagonally upward to attach to femoral condyle Anterior cruciate ligament and posterior cruciate ligament KNEE JOINT  ANKLE AND FOOT JOINTS Talocrural joint – ankle – articulations between talus and distal ends of tibia and fibula Subtalar joint – between talus and calcaneus bones  ANKLE AND FOOT JOINTS Talocrural Ligaments – From medial malleolus of tibia or lateral malleolus of fibula and anchor to talus and calcaneus bones Deltoid ligament – medial side Anterior talofibular and posterior talofibular – lateral side between talus bone and lateral malleolus of fibula Calcaneofibular ligament – lateral between calcaneus and fibula This OpenStax ancillary resource is © Rice University under a CC-BY 4.0 International license; it may be reproduced or modified but must be attributed to OpenStax, Rice University and any changes must be noted.  1 12 11 2 Lateral 13 Medial 10 3 9 4 7 5 8 6