Chapter 8 Joints of the Skeletal System Hole’s Human Anatomy and Physiology Twelfth Edition Shier w Butler w Lewis Chapter 8 Joints of the Skeletal System Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

8.1: Introduction Are known as articulations Functional junctions between bones Bind parts of skeletal system together Make bone growth possible Permit parts of the skeleton to change shape during childbirth Enable body to move in response to skeletal muscle contraction Three (3) classifications of joints will be considered

8.2: Classification of Joints (1) Fibrous joints Dense connective tissues connect bones Between bones in close contact These joints are also known as: Synarthrotic joints Considered immovable Amphiarthrotic joints Slightly movable Diarthrotic joints Freely movable (2) Cartilaginous joints Hyaline cartilage or fibrocartilage connect bones (3) Synovial joints Most complex Allow free movement

Fibrous Joints There are three (3) types of fibrous joints (synarthroses): Syndesmosis Suture Gomphosis Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Interosseus membrane of leg Syndesmosis: A sheet or bundle of fibrous tissue connecting bones Lies between tibia and fibula (interosseous membrane) Fibula Tibia Anterior tibiofibular ligament (interosseus ligament) Medial malleolus Lateral malleolus

Courtesy of John W. Hole, Jr. Fibrous Joints Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Suture: Between flat bones See teeth-like projections Thin layer of connective tissue connects bones Skull Parietal bone Margin of suture Sutural bones Suture Occipital bone (a) (b) Courtesy of John W. Hole, Jr. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Gomphosis: Cone-shaped bony process in a socket Tooth in jawbone Crown of tooth Root of tooth Alveolar process of mandible Periodontal ligament

Cartilaginous Joints There are two (2) types of cartilaginous joints (amphiarthroses): Synchondrosis Symphysis Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Thoracic vertebra First rib Costal cartilage Synchondrosis: Bands of hyaline cartilage unite bones Epiphyseal plate (temporary) Between manubrium and the first rib (costal cartilages) Manubrium

Fibrocartilage disc of symphysis pubis Cartilaginous Joints Symphysis: Pad of fibrocartilage between bones Pubic symphysis Joint between bodies of adjacent vertebrae Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Gelatinous core Spinous process Band of fibrocartilage Body of vertebra Pubis Intervertebral discs Fibrocartilage disc of symphysis pubis (a) (b)

8.3: General Structure of a Synovial Joint Synovial joints are freely moveable (diarthroses) There are three (3) types of diarthroses There are specific parts of a diarthroses: Articular cartilage Joint cavity Joint capsule Synovial membrane Synovial fluid Meniscus Bursae Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Spongy bone Joint capsule Joint cavity filled with synovial fluid Articular cartilage Synovial membrane

8.4: Types of Synovial Joints Uni-axial Hinge joint Pivot or trochoid joint Bi-axial Saddle or sellar joint Condylar or ellipsoidal joint Multi-axial Ball and socket joint Gliding or plane joint

Types of Synovial Joints Pivot Joint Between atlas (C1) and the dens of axis (C2) Hinge Joint Elbow joint Between phalanges Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Humerus Dens Transverse ligament Radius Atlas Axis Ulna (e) Pivot joint (d) Hinge joint

Types of Synovial Joints Saddle Joint Between carpal and 1st metacarpal (of thumb) Condylar Joint Between metacarpals and phalanges Between radius and carpals Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Metacarpal First metacarpal Trapezium Phalanx (f) Saddle joint (b) Condylar joint

Types of Synovial Joints Ball-and-Socket Joint Hip joint Shoulder joint Gliding Joint Between carpals Between tarsals Between facets of adjacent vertebrae Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Hip bone Head of femur in acetabulum Femur Carpals (a) Ball-and-socket joint (c) Plane joint

8.5: Types of Joint Movements Movement at a joint occurs when a muscle contracts and its fibers pull its moveable end (insertion) towards its fixed end (origin).

Types of Joint Movements Abduction/adduction Dorsiflexion/plantar flexion Flexion/extension/hyperextension Lateral flexion Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Hyperextension Extension Flexion Flexion Abduction Extension Adduction Dorsiflexion Plantar flexion © McGraw-Hill Companies / Womack Photography Ltd.

Types of Joint Movements Rotation Circumduction Supination/pronation Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Circumduction Supination Medial rotation Pronation Lateral rotation © McGraw-Hill Companies / Womack Photography Ltd.

Types of Joint Movements Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Eversion/inversion Protraction/retraction Elevation/depression Inversion Eversion Protraction Retraction Elevation Depression © McGraw-Hill Companies / Womack Photography Ltd.

8.6: Examples of Synovial Joints The shoulder, elbow, hip, and knee are large, freely moveable joints.

Shoulder Joint Ball-and-socket Head of humerus and glenoid cavity of scapula Loose joint capsule Bursae Ligaments prevent displacement Very wide range of movement (circumduction) Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Clavicle Acromion process Subdeltoid bursa Synovial membrane Joint capsule Joint cavity Humerus Articular cartilage Scapula (a)

Shoulder Joint (b) Joint capsule Joint cavity Head of humerus Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Joint capsule Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Joint cavity Acromion process Clavicle Coracoid process Coracoid process Joint capsule Clavicle Coracohumeral ligament Head of humerus Acromion process Transverse humeral ligament Subscapular bursa Articular cartilage Tendon of biceps brachii (long head) Glenohumeral ligaments Scapula Glenoid labrum Glenoid cavity Humerus Humerus Articular capsule (glenohumeral ligaments hidden) Scapula Triceps brachii (long head) (a) Scapula (b) (b) © Paul Reimann

Elbow Joint Hinge joint Gliding joint Flexion and extension Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Hinge joint Trochlea of humerus Trochlear notch of ulna Gliding joint Capitulum of humerus Head of radius Flexion and extension Many reinforcing ligaments Stable joint Humerus Joint capsule Synovial membrane Joint cavity Articular cartilage Coronoid process Anular ligament Radius Ulna Olecranon process Trochlea (a)

Ulnar collateral ligament Radial collateral ligament Elbow Joint Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Humerus Humerus Medial epicondyle Tendon of biceps brachii muscle Lateral epicondyle Anular ligament Radius Anular ligament Radius Ulna Coronoid process Ulnar collateral ligament Olecranon process Radial collateral ligament Ulna (a) (b)

Hip Joint Ball-and-socket joint Head of femur and acetabulum of coxa Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Ball-and-socket joint Head of femur and acetabulum of coxa Heavy joint capsule Many reinforcing ligaments Less freedom of movement than shoulder joint Circumduction Hip bone Joint cavity Articular cartilage Synovial membrane Ligamentum capitis Joint capsule Femur (a)

Hip Joint (b) Hip bone Ilium Ilium Articular cartilage Joint cavity Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Hip bone Ilium Ilium Articular cartilage Joint cavity Pubofemoral ligament Head of femur Iliofemoral ligament Pubis Joint capsule Greater trochanter Iliofemoral ligament Ischiofemoral ligament Femur Ischium Lesser trochanter Femur Femur (a) (b) (b) © Paul Reimann

Knee Joint Largest joint Most complex Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Largest joint Most complex Medial and lateral condyles of distal end of femur and Medial and lateral condyles of proximal end of tibia and Femur articulates anteriorly with patella Strengthened by many ligaments and tendons Menisci separate femur and tibia Bursae Femur Synovial membrane Suprapatellar bursa Quadriceps femoris tendon (patellar tendon) Patella Prepatellar bursa Joint cavity Articular cartilage Patellar ligament Menisci Infrapatellar bursa Joint capsule Tibia (a)

Knee Joint (b) Femur Tendon of adductor magnus (cut) Femur Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Femur Tendon of adductor magnus (cut) Femur Anterior cruciate ligament Joint capsule Posterior cruciate ligament Femur Gastroc- nemius muscle (cut) Lateral condyle Plantaris muscle (cut) Medial condyle Lateral condyle Lateral meniscus Anterior cruciate ligament Tendon of semimembranosus (cut) Oblique popliteal ligament Lateral meniscus Articular cartilage Medial meniscus Tibial collateral ligament Fibular collateral ligament Lateral condyle Medial condyle Lateral condyle Popliteus muscle cut) Fibular collateral ligament Arcuate popliteal ligament Tibial collateral ligament Head of fibula Tibia Fibula Patellar ligament (cut) Tibia Fibula Fibula Tibia (b) (a) (b) © Paul Reimann

8.7: Lifespan Changes Joint stiffness is an early sign of aging Fibrous joints first to change; can strengthen however over a lifetime Changes in symphysis joints of vertebral column diminish flexibility and decrease height (remember water loss from the IVDs) Synovial joints lose elasticity Disuse hampers the blood supply Activity and exercise can keep joints functional longer

Important Points in Chapter 8: Outcomes to be Assessed 8.1: Introduction List the functions of joints. 8.2: Classification of Joints Explain how joints can be classified according the type of tissue that binds the bones together. Describe how bones of fibrous joints are held together. Describe how bones of cartilaginous joints are held together. 8.3: General Structure of a Synovial Joint Describe the general structure of a synovial joint. 8.4: Types of Synovial Joints Distinguish among the six types of synovial joints and give an example of each type. 8.5: Types of Joint Movements Explain how skeletal muscles produce movements at joints, and identify several types of joint movements.

Important Points in Chapter 8: Outcomes to be Assessed 8.6: Examples of Synovial Joints Describe the shoulder joint and explain how its articulating parts are held together. Describe the elbow, hip, and knee joints and explain how their articulating parts are held together. 8.7: Lifespan Changes Describe lifespan changes in joints.