A&P Ch. 9 PPT Articulations Quinn(1) PDF

Chapter 9 Articulations https://www.youtube.com/watch?v=DLx YDoN634c https://www.youtube.com/watch?v=8hq yQIyenxA  Skeletal System: Articulations Bones are too rigid to bend – Meet at joints called articulations – Different joints with different shapes and supporting struc...

Chapter 9 Articulations https://www.youtube.com/watch?v=DLx YDoN634c https://www.youtube.com/watch?v=8hq yQIyenxA  Skeletal System: Articulations Bones are too rigid to bend – Meet at joints called articulations – Different joints with different shapes and supporting structures – Allow for different types and ranges of movement  Classification of Joints Joint (articulation) – Place of contact between bones, bone and cartilage, or bones and teeth – Bones said to articulate at a joint – Arthrology, scientific study of joints – Classified by structural characteristics and type of movement allowed  Classification of Joints Structural classification of joints – Fibrous joint has no joint cavity bones held together by dense connective tissue e.g., lambdoid suture – Cartilaginous joint has no joint cavity bones joined by cartilage e.g., intervertebral disc articulations  Classification of Joints Structural classification of joints (continued) – Synovial joint fluid-filled joint cavity separating articulating surfaces of bones surfaces enclosed within connective tissue bones attached by ligaments e.g., elbow joint  Fibrous Joints Sutures Gomphosis Syndesmosis (Teeth) (Interosseous membrane)  Cartilaginous Joints Symphysis Pubic symphysis Intervertebral discs 7 Knee MRI  Classification of Joints Functional classification of joints – Synarthrosis immobile joint can be fibrous or cartilaginous joint e.g., tooth to jaw – Amphiarthrosis slightly mobile joint can be fibrous or cartilaginous joint e.g., articulation between tibia and fibula  Classification of Joints Functional classification of joints (continued) – Diarthrosis freely mobile joints all synovial joints e.g., knee joint See Table 9.1  Classification of Joints Range of motion at joints – Motion ranges from no movement to extensive movement – Structure of each joint determines mobility and stability – Inverse relationship between mobility and stability “tradeoff” between mobility and stability Could you graph this relationship?  Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 9.1 In every joint, there is a tradeoff between mobility and stability. Stable (yet limited mobility) The more stable a joint, the less mobile it is. Fibrous Joints Their primary function is to hold two bones together. They are immobile or slightly mobile. Examples: Sutures and interosseous membrane Immobile Most Cartilaginous Joints stable Suture Their primary function is to resist compression and tension stress and act as resilient shock absorbers. They are immobile or slightly mobile. Example: Intervertebral joints Interosseous membrane Synovial Joints Their primary function is movement, so they are all Slightly Stable freely mobile. Examples: mobile Glenohumeral joint (shoulder), and knee joint Intervertebral joints Knee joint Most Most mobile unstable Glenohumeral joint (shoulder) Mobile (yet more unstable) The more mobile a joint, the less stable it is.  Fibrous Joints Characteristics of fibrous joints – Connected by dense regular connective tissue – Have no joint cavity – Immobile or only slightly mobile – E.g., teeth in sockets, sutures between skull, between radius and ulna – Three most common types: gomphoses, sutures, syndesmoses  Fibrous Joints: Gomphoses Gomphoses, “peg in a socket” – Articulation of teeth with sockets of mandible and maxillae only one in human body (synarthrosis) – Tooth held in place by fibrous periodontal membranes – Architecture of gomphosis relates to pain and length of orthodontic braces  Fibrous Joints: Sutures Sutures, immobile fibrous joints – Found only between certain bones of the skull – Have interlocking, usually irregular edges increase strength and decrease number of fractures – Permit skull to grow as brain increases in size during childhood – Become ossified in older adult – When obliterated become synostoses completely fused across the suture line  Fibrous Joints: Syndesmoses Syndesmoses – Joined by long strands of dense regular connective tissue – Allow for slight mobility (amphiarthroses) – Found between radius and ulna and tibia and fibula – Bound by interosseous membrane, broad ligamentous sheet – Provides a pivot radius and ulna able to move against one another  Figure 9.2 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Suture Ulna Radius Syndesmosis Root of (interosseous tooth membrane) Periodontal membranes Gomphosis Alveolar process of mandible (a) Gomphosis (b) Suture (c) Syndesmosis  Cartilaginous Joints Properties of cartilaginous joints – Have cartilage between articulating bones either hyaline or fibrocartilage – Lack a joint cavity – Immobile or slightly mobile – Synchondroses or symphyses  Cartilaginous Joints: Synchondroses Synchondrosis – Bones joined by hyaline cartilage – All immobile (synarthroses) – E.g., hyaline cartilage of epiphyseal plates synchondrosis binding epiphyses and diaphysis cartilage ultimately replaced – E.g., spheno-occipital synchondrosis found between body of sphenoid and basilar occipital bone fuses between ages 18 to 25 – E.g., costal cartilage costochondral joint between bony rib and costal cartilage – E.g., attachment of first rib to sternum united firmly to manubrium provides stability to the rib cage Cartilaginous Joints Synchondrosis 20  Cartilaginous Joints: Symphyses Symphysis – Pad of fibrocartilage between articulating bones resists compression and acts as shock absorber – All symphyses allow slight mobility (amphiarthroses) – E.g., pubic symphysis, between right and left pubic bones become more mobile during pregnancy – E.g., intervertebral joints bodies of adjacent vertebrae separated by intervertebral discs allow only slight movements between adjacent vertebrae together allow spine considerable flexibility  Cartilaginous Joints Symphysis Pubic symphysis Intervertebral discs 22  Figure 9.3 Synchondroses (contain hyaline cartilage) Symphyses (contain fibrocartilage) Costochondral joints Intervertebral Intervertebral disc Epiphyseal plate (immobile joints between the joint rib and its costal cartilage) Joint between first rib and sternum Pubic symphysis Body of vertebra (a) (b)  Cartilaginous Joints Clinical View: Costochondritis – Inflammation of the costochondral joints – Localized chest pain – Cause usually unknown (trauma or infection) – May be mistaken for pain from a myocardial infarction – Treated with nonsteroidal anti-inflammatory drugs  Synovial Joints: Distinguishing Features and Anatomy Synovial joints – Freely mobile articulations – Include most joints in the body – Bones separated by a space, the joint cavity – All diarthroses – All with the basic features: articular capsule and joint cavity synovial fluid articular cartilage ligaments, nerves, and blood vessels  Synovial Joints: Distinguishing Features and Anatomy Joint capsule – Double-layered capsule termed articular capsule – Outer layer, fibrous layer formed from dense connective tissue strengthens joints to prevent bones being pulled apart – Inner layer, synovial membrane composed primarily of areolar connective tissue covers all internal joint surfaces not covered by cartilage helps produce synovial fluid  Synovial Joints: Distinguishing Features and Anatomy Articular cartilage – Articulating bone covered by this hyaline cartilage – Has numerous functions: reduces friction during movement acts as a cushion to absorb joint compression prevents damage to articulating ends of bones – Lacks a perichondrium – Avascular (like all cartilage)  Synovial Joints: Distinguishing Features and Anatomy Joint cavity – Space permitting separation of articulating bones – Lined by synovial membrane secreting synovial fluid viscous, oily substance secretions from synovial membrane cells and filtrate from plasma  Synovial Joints: Distinguishing Features and Anatomy Three functions of synovial fluid: 1) lubricates articular cartilage on articulating surfaces 2) nourishes and removes wastes from articular cartilage’s chondrocytes 3) acts as a shock absorber  Synovial Joints: Distinguishing Features and Anatomy Ligaments – Dense regular connective tissue – Connect one bone to another bone – Stabilize, strengthen, and reinforce most synovial joints – Extrinsic ligaments physically separate from the joint capsule – Intrinsic ligaments thickening of the articular capsule itself include ligaments outside and within the joint capsule  Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Periosteum Figure 9.4 Yellow bone marrow Fibrous layer Synovial Articular membrane capsule Joint cavity (containing synovial fluid) Articular cartilage Ligament Typical synovial joint  ALE Think-Pair-Share In my knee joint, if I ran a mile, how would my synovial fluid help me?  Synovial Joints: Distinguishing Features and Anatomy Sensory nerves and blood vessels – Numerous in synovial joints – Innervate and supply articular capsule and ligaments – Detect painful stimuli in the joint – Report on movement and stretch within the joint  Synovial Joints: Distinguishing Features and Anatomy Tendons – Composed of dense regular connective tissue – Not part of the synovial joint itself – Attache muscle to bone muscle moving the bone where attached – Help stabilize joints – Sometimes limit range of movement permitted at a joint  Tendons Calcaneal Tendons of Tendons of (Achilles) Flexor digitorum Biceps brachii tendon superficialis  Synovial Joints: Distinguishing Features and Anatomy Bursa – Fibrous, saclike structure containing synovial fluid – Lined internally by synovial membrane – Associated with most synovial joints – Found where bones, ligaments, muscles, skin, or tendons rub together – Connected to the joint cavity or separate from it – Alleviate friction resulting from body movements  Synovial Joints: Distinguishing Features and Anatomy Other accessory structures – Tendon sheath, elongated bursa wraps around tendons where there may be excessive friction especially common in wrist and ankle – Fat pads act as packing material provide some joint protection often distributed along periphery of a synovial joint often fill spaces formed when joint shape changes  Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 9.5a Femur Suprapatellar bursa Bursa deep to gastrocnemius Synovial membrane muscle Articular capsule Patella Articular cartilage Prepatellar bursa Meniscus Fat pad Joint cavity Infrapatellar bursae filled with synovial fluid Patellar Tibia ligament (a) Bursae of the knee joint, sagittal section  Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Tendon sheath (opened) Tendon of flexor digitorum profundus Tendon of flexor digitorum superficialis Digital tendon sheaths Figure 9.5b Tendon sheath around flexor pollicis longus Common flexor tendon tendon sheath Tendon of flexor carpi radialis Tendons of flexor digitorum superficialis Tendon of flexor and flexor digitorum pollicis longus profundus (b) Tendon sheaths of wrist and hand, anterior view  ALE Think-Pair-Share What are the basic characteristics of all types of synovial joints? All are freely mobile articulations with articular capsule, joint cavity, synovial fluid, articular cartilage, ligaments, nerves, and blood vessels.  Synovial Joints: Classification of Synovial Joints Classified by shapes of surfaces and movement allowed – Uniaxial joint bone moves in just one plane or axis – Biaxial joint bone moves in two planes or axes – Multiaxial joint bone moves in multiple planes or axes  Synovial Joints: Classification of Synovial Joints Joints (diathroses), from least to most mobile: – plane joints – hinge joints – pivot joints – condylar joints – saddle joints – ball-and-socket joints See Figure 9.6  Synovial Joints: Classification of Synovial Joints Plane joint – Simplest synovial articulation – Least mobile type of diarthrosis – Uniaxial joint – Limited side-to-side movement in a single plane – Articular surfaces flat – E.g., intercarpal and intertarsal joints  Gliding (Plane) Joints Between articular processes of Ankle adjacent vertebrae Wrist Sacroiliac joint Ribs 2-7 connecting to sternum  Synovial Joints: Classification of Synovial Joints Hinge joint – Formed by convex surface fitting into concave depression – Movement confined to a single axis, so uniaxial – Like the hinge of a door – E.g., elbow joint, knee, and interphalangeal joints  Hinge Joint Joints between Elbow joint phalanges (Humeroulnar joint)  Synovial Joints: Classification of Synovial Joints Pivot joint – Bone with rounded surface fits into ring formed by ligament from another bone rotates on longitudinal axis relative to second bone – Uniaxial joint – E.g., proximal radioulnar joint rounded head of radius pivoting along ulna permits radius to rotate – E.g., dens of axis and anterior arch of atlas pivots when shake head “no”  Pivot Joint Elbow joint Between Atlas (C1) and Axis (C2) (Humeroradial joint) (Atlantoaxial joint)  Synovial Joints: Classification of Synovial Joints Condylar joint – Biaxial joint, moving in two planes – Oval, convex surface articulating with concave surface – E.g., metacarpophalangeal joints of fingers 2 to 5 (knuckles) can flex and extend the fingers can also move fingers apart from one another Condylar (Ellipsoidal) Joint Metacarpophalangeal joints  Synovial Joints: Classification of Synovial Joints Saddle joint – Convex and concave surfaces resembling saddle shape – Biaxial – Greater range of movement than condylar or hinge joint – E.g., carpometacarpal joint of the thumb permits thumb to move toward other fingers  Saddle Joint Between trapezium and metacarpal of thumb  Synovial Joints: Classification of Synovial Joints Ball-and-socket joint – Multiaxial joints, permitting movement in 3 planes – Spherical head of one bone fitting into cuplike socket – E.g., coxal and glenohumeral joints – Considered the most freely mobile type  Ball-and-Socket Joint Glenohumeral joint Coxal Joint  ALE Think-Pair-Share List the six kinds of joints and indicate if they are uniaxial, biaxial, or multiaxial. Plane joint, hinge joints, and pivot joints are considered uniaxial. Condylar and saddle joints are considered biaxial. Ball- and-socket joints are multiaxial.  Synovial Joints and Levers: Terminology of Levers Lever – Elongated, rigid object – Rotates around fixed point, fulcrum – Has ability to change: speed and distance of movement produced by a force direction of applied force force strength  Synovial Joints and Levers: Terminology of Levers Lever definitions – Effort applied to one point – Resistance located at some other point – Movement if effort exceeds resistance – Effort arm part of lever from fulcrum to point of effort – Resistance arm part of lever from fulcrum to point of resistance  Synovial Joints and Levers: Terminology of Levers Biomechanics – Practice of applying mechanical principles to biology – E.g., comparing joint movement and muscle contraction to a lever long bone as lever joint as fulcrum effort generated by muscle  Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Types of Levers First-class lever Resistance Effort First-Class Levers R E – Have fulcrum in the Resistance arm F Effort arm middle, between effort Fulcrum and resistance – E.g., pair of scissors Resistance – Effort applied to handle R of scissors Effort – Fulcrum along the F Fulcrum E middle of scissors – E.g., atlanto-occipital joint of the neck muscles on posterior neck pulling inferiorly oppose tendency of R F head to tip anteriorly Resistance Fulcrum Figure 9.7a Effort E (a)  Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Types of Levers Second-class lever Resistance Second-Class Levers Resistance arm R – Resistance between the F Effort arm E fulcrum and effort Fulcrum Effort – E.g., lifting handles of wheelbarrow Resistance – Fulcrum farther from R E effort Effort – Small force able to F balance larger weight Fulcrum – Rare in the body – One example, standing on E tip toe Effort contraction of calf muscles with pull superiorly R Figure 9.7b F Resistance Fulcrum (b)  Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Third-class lever Types of Levers Resistance Effort R Effort arm E Third-Class Levers Resistance arm F – Effort applied between Fulcrum resistance and fulcrum – E.g., picking up an object Resistance with forceps R – Most common in body – E.g., at elbow joint E F Effort Fulcrum fulcrum the joint between humerus and ulna effort applied by biceps brachii Effort resistance provided by R E weight in hand or weight Resistance of forearm Figure 9.7c F Fulcrum (c)  ALE Draw it! Draw each of the three lever classes and detail where the resistance, fulcrum, and effort are.  The Movements of Synovial Joints: Gliding Motion Gliding – One of the four types of motion occurring at synovial joints – Two opposing surfaces sliding back-and-forth or side-to-side – Angle between bones unchanged – Only limited movement possible in any direction – Typically occurs along plane joints – E.g., between carpals or tarsals  The Movements of Synovial Joints: Angular Motion Angular motion – One of the four types of motion occurring at synovial joints – Either increases or decreases angle between two bones – Include specific types: flexion, extension, hyperextension, and lateral flexion abduction and adduction circumduction  The Movements of Synovial Joints: Angular Motion Flexion – Movement in an anterior-posterior plane – Decreases the angle between bones – Bones brought closer together – E.g., bending finger toward the palm Extension – Opposite of flexion – Increases angle between articulating bones – E.g., straightening your fingers after making a fist  The Movements of Synovial Joints: Angular Motion Hyperextension – Joint extended more than 180 degrees – E.g., glancing up at the ceiling while standing neck hyperextended Lateral flexion – Trunk of body moving in coronal plane laterally – Occurs primarily between vertebrae in the cervical and lumbar region  Figure 9.8 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Flexion Extension Hyperextension Hyperextension Flexion Lateral flexion Extension Extension Flexion Flexion Extension (a) (b) (c) (d) (e) a, d: © The McGraw-Hill Companies, Inc./Eric Wise, photographer; (b, c, e): © The McGraw-Hill Companies, Inc./JW Ramsey, photographer  The Movements of Synovial Joints: Angular Motion Abduction – Lateral movement of body part away from midline – E.g., arm or thigh moved laterally from body midline – Abduction of fingers finger spread away from longest digit (acting as midline) Adduction – Medial movement of body part toward midline – E.g., thigh brought back to midline  Figure 9.9 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Abduction Adduction Abduction Adduction Abduction Abduction Adduction (a) (b) Adduction (c) (d) (a-c): © The McGraw-Hill Companies, Inc./JW Ramsey, photographer; d(left)-(right): © The McGraw-Hill Companies, Inc./Eric Wise, photographer  The Movements of Synovial Joints: Angular Motion Circumduction Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. – Proximal end of appendage relatively stationary – Distal end makes a circular motion – Movement makes an Circumduction imaginary cone shape – E.g., drawing a circle on the blackboard – Occurs as a result of (a) (b) Circumduction flexion, abduction, extension, adduction (both) © The McGraw-Hill Companies, Inc./JW Ramsey, photographer Figure 9.10  The Movements of Synovial Joints: Rotational Motion Rotation – Bone pivoting on its own longitudinal axis – Lateral rotation turns anterior surface of femur or humerus laterally – Medial rotation turns anterior surface of femur or humerus medially – Pronation medial rotation of forearm so palm of the hand posterior – Supination lateral rotation of forearm so palm of the hand anterior  Figure 9.11 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Lateral rotation Medial rotation Lateral Medial rotation rotation Rotation Pronation Supination (a) (b) (c) (d) (all): © The McGraw-Hill Companies, Inc./JW Ramsey, photographer  Features and Anatomy of Selected Joints There are many more joints than we will cover – Main features of major joints of axial skeleton (See Table 9.3) – Main features of major joints of pectoral girdle and upper limbs (See Table 9.4) – Main features of major joints of pelvic girdle and lower limbs (See Table 9.5)  Features and Anatomy of Selected Joints: Knee Joint Knee joint – Largest and most complex diarthrosis – Primarily a hinge joint – Capable of slight rotation and lateral gliding when flexed – Composed of two separate articulations: 1) tibiofemoral joint between condyles of femur and condyles of tibia 2) patellofemoral joint between patella and patellar surface of femur Knee – Most Complex Joint Knee  Knee Xrays A-P View P-A View Lateral View  Features and Anatomy of Selected Joints: Knee Joint Structures of the knee joint – Articular capsule encloses medial, lateral, and posterior knee regions – Quadriceps femoris muscle tendon passes over knee’s anterior surface patella embedded here – Patellar ligament extends from patella to tibial tuberosity – No single unified capsule or joint cavity Surface Projection of Patella Surface Projection of Patellar Ligament Surface Projection of Tibial Tuberosity  Features and Anatomy of Selected Joints: Knee Joint Structures of the knee joint (continued) – Fibular collateral ligament reinforces lateral surface of joint extends from femur to fibula prevents hyperadduction of leg at the knee – Tibial collateral ligament reinforces medial surface of knee joint extends from femur to tibia prevents hyperabduction of leg at the knee Fibular (Lateral) Collateral Ligament Tibial (Medial) Collateral Ligament  Features and Anatomy of Selected Joints: Knee Joint Structures of the knee joint (continued) – Medial meniscus and lateral meniscus deep to articular capsule within knee joint c-shaped fibrocartilage pads positioned on condyles of tibia partially stabilize joint medially and laterally act as cushioning between articular surfaces change shape to conform to articulating surfaces Medial Meniscus Lateral Meniscus  Features and Anatomy of Selected Joints: Knee Joint Structures of the knee joint (continued) – Cruciate ligaments deep to the articular capsule of knee joint limit anterior and posterior movement of femur on tibia cross each other in an X – Anterior cruciate ligament (ACL) extends from posterior femur to anterior tibia prevents hyperextension prevents tibia moving too far anteriorly on the femur Anterior Cruciate Ligament  Features and Anatomy of Selected Joints: Knee Joint Structures of the knee joint (continued) – Posterior cruciate ligament (PCL) runs from anteroinferior femur to posterior tibia prevents hyperflexion prevents posterior displacement of tibia on the femur Posterior Cruciate Ligament Figure 9.18a-b Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Flexion Femur Gastrocnemius muscle heads (cut) Extension Quadriceps Articular femoris capsule muscle Quadriceps Oblique femoris popliteal ligament Fibular tendon collateral ligament Tibial Tibial Fibular collateral Arcuate collateral popliteal collateral ligament ligament ligament ligament Patella within quadriceps Popliteus Fibula Patellar muscle tendon ligament (cut) Tibia (b) Right knee, posterior superficial view Fibula Tibia (a) Right knee, anterior superficial view Anterior Knee Posterior Knee  Figure 9.18c-d Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Femur Articular cartilage Anterior cruciate ligament Posterior Lateral cruciate condyle ligament Medial Fibular Lateral condyle collateral condyle Medial ligament condyle Medial Lateral Lateral meniscus meniscus meniscus Medial meniscus Posterior Fibular cruciate collateral Anterior ligament ligament cruciate ligament Tibial collateral ligament Tibial collateral Fibula ligament Tibia Fibula Tibia (c) Right knee, anterior deep view (d) Right knee, posterior deep view  Features and Anatomy of Selected Joints: Knee Joint Clinical View: Knee Ligament and Cartilage Injuries – Tibial collateral ligament injury injured when leg forcibly abducted at the knee medial meniscus frequently involved – Fibular collateral ligament injury injured if medial side of knee struck rare – ACL injury injured when leg hyperextended especially prone to injury  Features and Anatomy of Selected Joints: Knee Joint Clinical View: Knee Ligament and Cartilage Injuries (continued) – PCL injury injured if leg hyperflexed rare – Menisci injury may occur due to blows at the knee or overuse – Unhappy triad triple injury of tibial collateral ligament, medial meniscus, and ACL occurs when football player gets lateral blow to knee leg abducted and laterally rotated – Treatment depends on severity and type