© 2015 Pearson Education, Inc.

An Introduction to Joints Learning Outcomes 9-1 Contrast the major categories of joints, and explain the relationship between structure and function for each category. 9-2 Describe the basic structure of a synovial joint, and describe common synovial joint accessory structures and their functions. 9-3 Describe how the anatomical and functional properties of synovial joints permit movements of the skeleton. 9-4 Describe the joints between the vertebrae of the vertebral column. © 2015 Pearson Education, Inc.

An Introduction to Joints Learning Outcomes 9-5 Describe the structure and function of the shoulder joint and the elbow joint. 9-6 Describe the structure and function of the hip joint and the knee joint. 9-7 Describe the effects of aging on joints, and discuss the most common age-related clinical problems for joints. 9-8 Explain the functional relationships between the skeletal system and other body systems. © 2015 Pearson Education, Inc.

An Introduction to Joints Articulations Body movement occurs at joints (articulations) where two bones connect Joint Structure Determines direction and distance of movement (range of motion or ROM) Joint strength decreases as mobility increases © 2015 Pearson Education, Inc.

9-1 Classification of Joints Two Methods of Classification Functional classification is based on range of motion of the joint Synarthrosis (immovable joint) Amphiarthrosis (slightly movable joint) Diarthrosis (freely movable joint) Structural classification relies on anatomical organization of the joint Bony Fibrous Cartilaginous Synovial © 2015 Pearson Education, Inc.

9-1 Classification of Joints Synarthroses (Immovable Joints) Are very strong Edges of bones may touch or interlock Four types of synarthrotic joints Suture Gomphosis Synchondrosis Synostosis © 2015 Pearson Education, Inc.

9-1 Classification of Joints Suture Bones interlocked and are bound by dense fibrous connective tissue which found only in skull Gomphosis Fibrous connection (periodontal ligament) Binds teeth to sockets © 2015 Pearson Education, Inc.

Table 9-1 Functional and Structural Classifications of Joints (Part 1 of 3).

9-1 Classification of Joints Synchondrosis Is a rigid cartilaginous bridge between two bones Epiphyseal cartilage of long bones and between vertebrosternal ribs and sternum Synostosis Fused bones, immovable in metopic suture of skull and epiphyseal lines of long bones © 2015 Pearson Education, Inc.

9-1 Classification of Joints Amphiarthroses More movable than synarthrosis Stronger than freely movable joint Two types of amphiarthroses Syndesmosis: Bones connected by ligaments Symphysis: Bones separated by fibrocartilage © 2015 Pearson Education, Inc.

Table 9-1 Functional and Structural Classifications of Joints (Part 2 of 3).

9-1 Classification of Joints Synovial Joints (Diarthroses) Also called movable joints are at ends of long bones, within articular capsules which lined with synovial membrane © 2015 Pearson Education, Inc.

Table 9-1 Functional and Structural Classifications of Joints (Part 3 of 3).

9-2 Synovial Joints Articular Cartilages Pad articulating surfaces within articular capsules which prevent bones from touching Smooth surfaces lubricated by synovial fluid will reduce friction © 2015 Pearson Education, Inc.

9-2 Synovial Joints Synovial Fluid Contains slippery proteoglycans secreted by fibroblasts Functions of synovial fluid Lubrication Nutrient distribution Shock absorption © 2015 Pearson Education, Inc.

9-2 Synovial Joints Accessory Structures Cartilages Fat pads Ligaments Tendons Bursae © 2015 Pearson Education, Inc.

9-2 Synovial Joints Cartilages: Cushion the joint Fibrocartilage pad called a meniscus (or articular disc; plural, menisci) Fat Pads: Superficial to the joint capsule and Protect articular cartilages Ligaments: Support, strengthen joints Sprain – ligaments with torn collagen fibers © 2015 Pearson Education, Inc.

9-2 Synovial Joints Tendons Bursae Attach to muscles around joint and help support joint Bursae Singular, bursa, a pouch Pockets of synovial fluid Cushion areas where tendons or ligaments rub © 2015 Pearson Education, Inc.

Figure 9-1a The Structure of a Synovial Joint. Medullary cavity Spongy bone Periosteum Components of Synovial Joints Joint capsule Synovial membrane Articular cartilages Joint cavity containing synovial fluid Metaphysis Compact bone a Synovial joint, sagittal section

Figure 9-1b The Structure of a Synovial Joint. Quadriceps tendon Patella Accessory Structures of a Knee Joint Joint capsule Femur Synovial membrane Bursa Fat pad Joint cavity Articular cartilage Meniscus Ligaments Tibia Extracapsular ligament (patellar) Intracapsular ligament (cruciate) b Knee joint, sagittal section

9-2 Synovial Joints Injuries Dislocation (luxation) Subluxation Articulating surfaces forced out of position Damages articular cartilage, ligaments, joint capsule Subluxation A partial dislocation © 2015 Pearson Education, Inc.

9-3 Movements Three Types of Dynamic Motion Linear movement (gliding) Angular movement Rotation Planes (Axes) of Dynamic Motion Monaxial (1 axis) Biaxial (2 axes) Triaxial (3 axes) © 2015 Pearson Education, Inc.

Figure 9-2 Joint Movement (Part 1 of 12). SIMPLE MODEL OF ARTICULAR MOTION Take a pencil as your model and stand it upright on the surface of a desk. The pencil represents a bone, and the desk is an articular surface. A lot of twisting, pushing, and pulling will demonstrate that there are only three ways to move the pencil.

Figure 9-2 Joint Movement (Part 2 of 12). Moving the Point Linear motion (glinding) Possible movement 1 shows the pencil can move. If you hold the pencil upright, without securing the point, you can push the pencil across the surface which is called gliding. You could slide the point forward or backward, from side to side, or diagonally. Two surfaces slide past each other Between carpal or tarsal bones

Figure 9-2 Joint Movement (Part 3 of 12). Changing the Shaft Angle Angular motion Possible movement 2 shows the pencil shaft can change its angle with the surface. With the tip held in position, you can move the eraser end of the pencil forward and backward, from side to side, or at some intermediate angle.

Figure 9-2 Joint Movement (Part 4 of 12). Changing the Shaft Angle Circumduction Possible movement 3 shows a complex angular movement. Grasp the pencil eraser and move the pencil in any direction until it is no longer vertical. Now, swing the eraser through a complete circle in a movement called circumduction.

Figure 9-2 Joint Movement (Part 5 of 12). Rotating the Shaft Rotation Possible movement 4 shows that the pencil shaft can rotate. If you keep the shaft vertical and the point at one location, you can still spin the pencil around its longitudinal axis in a movement called rotation. No joint can freely rotate because this would tangle blood vessels, nerves, and muscles as they crossed the joint.

Figure 9-3a Angular Movements. Extension Angular motion in anterior–posterior plane reduces angle between elements Flexion Hyperextension Flexion Flexion Hyper- extension increases angle between elements Extension Extension Flexion Hyperextension Angular motion in extension past anatomical position Extension a Flexion/extension

Figure 9-3b Angular Movements. Angular motion in frontal plane which moves away from longitudinal axis Abduction Abduction Adduction Adduction Abduction Adduction Abduction Adduction moves toward longitudinal axis b Abduction/adduction

9-3 Movements Angular Movement Circumduction Circular motion without rotation Angular motion © 2015 Pearson Education, Inc.

Figure 9-4a Rotational Movements. Head rotation Right rotation Left rotation Left or right rotation Medial rotation (inward rotation) Rotates toward axis Lateral (external) rotation Medial (internal) rotation Lateral rotation (outward rotation) Rotates away from axis a

Figure 9-4b Rotational Movements. Supination: Forearm in anatomical position Pronation b Supination Pronation: Rotates forearm, radius over ulna

9-3 Movements Special Movements Inversion: Twists sole of foot medially Eversion: Twists sole of foot laterally Dorsiflexion: Flexion at ankle (lifting toes) Plantar flexion: Extension at ankle (pointing toes) Dorsiflexion (Lifting up) Eversion Inversion Plantar flexion (Pointing toes) © 2015 Pearson Education, Inc.

9-3 Movements Special Movements Opposition: Thumb movement toward fingers or palm (grasping) Reposition: Opposite of opposition Protraction: Moves interiorly in the horizontal plane (pushing forward) Retraction: Opposite of protraction which move anteriorly (pulling back) © 2015 Pearson Education, Inc.

9-3 Movements Special Movements Elevation: Moves in superior direction (up) Depression: Moves in inferior direction (down) Lateral flexion: Bends vertebral column from side to side © 2015 Pearson Education, Inc.

Figure 9-5 Special Movements (Part 3 of 6). Retraction Protraction Depression Elevation Opposition Lateral flexion

9-3 Movements Functional Classification of Synovial Joints Gliding Hinge Pivot Condylar Saddle Ball-and-socket © 2015 Pearson Education, Inc.

9-3 Movements Gliding Joints Hinge Joints Condylar Joints Flattened or slightly curved faces Limited motion (nonaxial) Hinge Joints Angular motion in a single plane (monaxial) Condylar Joints Oval articular face within a depression Motion in two planes (biaxial) © 2015 Pearson Education, Inc.

Figure 9-2 Joint Movement (Part 7 of 12). Gliding joint Gliding joints, or plane joints, have flattened or slightly curved surfaces that slide across one another, but the amount of movement is very slight. Clavicle Movement: Gliding. Slight nonaxial or multiaxial Manubrium Flattened or slightly curved faces and there is limited motion (nonaxial)

Figure 9-2 Joint Movement (Part 8 of 12). Hinge joint Movement: Angular Monaxial Examples: Elbow joint Knee joint Ankle joint Interphalangeal joint Hinge joints permit angular motion in a single plane, like the opening and closing of a door. Humerus Ulna Angular motion in a single plane (monoaxial)

Figure 9-2 Joint Movement (Part 9 of 12). Condylar joint Condylar joints, or ellipsoidal joints, have an oval articular face nestled within a depression on the opposing surface. Examples: Radiocarpal joint Metacarpophalangeal joints 2–5 Metatarsophalangeal joint Movement: Angular. Biaxial Scaphoid bone Radius Ulna Oval articular face within a depression and motion in two planes (biaxial)

9-3 Movements Saddle Joints: Two concave, straddled (biaxial) Pivot Joints: Rotation only (monaxial) Ball-and-Socket Joints: Round articular face in a depression (triaxial) © 2015 Pearson Education, Inc.

Figure 9-2 Joint Movement (Part 10 of 12). Saddle joint Saddle joints have complex articular faces and fit together like a rider in a saddle. Each face is concave along one axis and convex along the other. Movement: Angular. Biaxial Examples: First carpometacarpal joint III II Metacarpal bone of thumb Trapezium Two concave, straddled (biaxial)

Figure 9-2 Joint Movement (Part 11 of 12). Pivot joint Pivot joints only permit rotation. Movement: Rotation. Monaxial Examples: Atlantoaxial joint Proximal radioulnar joint Atlas Axis Rotation only (monaxial)

Figure 9-2 Joint Movement (Part 12 of 12). Ball-and-socket joint In a ball-and-socket joint, the round head of one bone rests within a cup-shaped depression in another. Examples: Shoulder joint Hip joint Movement: Angular, circumduction, and rotation. Triaxial Scapula Humerus Round articular face in a depression (triaxial)

9-3 Movements Joints Intervertebral Joints A joint cannot be both mobile and strong and the greater the mobility, the weaker the joint will be , the mobile joints are supported by muscles and ligaments, not bone-to-bone connections Intervertebral Joints C2 to L5 spinal vertebrae articulate: At inferior and superior articular processes (gliding joints) and between adjacent vertebral bodies (symphyseal joints) © 2015 Pearson Education, Inc.

9-4 Intervertebral Joints Intervertebral Discs: are pads of fibrocartilage and separate vertebral bodies Anulus fibrosus: are tough outer layer which attaches disc to vertebrae Nucleus pulposus: are elastic, gelatinous core which absorbs shocks © 2015 Pearson Education, Inc.

Figure 9-6a Intervertebral joints. Superior articular process Intervertebral Ligaments Ligamentum flavum Posterior longitudinal ligament Anterior longitudinal ligament a Anterior view

Figure 9-6b Intervertebral joints. Superior articular facet Intervertebral Disc Intervertebral foramen Vertebral end plate Intervertebral Ligaments Anulus fibrosus Ligamentum flavum Nucleus pulposus Spinal cord Posterior longitudinal ligament Spinal nerve Interspinous ligament Supraspinous ligament Anterior longitudinal ligament b Lateral and sectional view

9-4 Intervertebral Joints Vertebral Joints called symphyseal joints As vertebral column moves: Nucleus pulposus shifts and disc shape conforms to motion Intervertebral Ligaments Bind vertebrae together and stabilize the vertebral column © 2015 Pearson Education, Inc.

9-4 Intervertebral Joints Six Intervertebral Ligaments Anterior longitudinal ligament: Connects anterior bodies Posterior longitudinal ligament: Connects posterior bodies Ligamentum flavum: Connects laminae Interspinous ligament : Connects spinous processes Supraspinous ligament: Connects tips of spinous processes (C7 to sacrum) Ligamentum nuchae: Continues supraspinous ligament (C7 to skull) © 2015 Pearson Education, Inc.

9-4 Intervertebral Joints Damage to Intervertebral Discs Slipped disc Bulge in anulus fibrosus Invades vertebral canal Herniated disc Nucleus pulposus breaks through anulus fibrosus Presses on spinal cord or nerves Bulging disc showing the release of the nucleus pulposus and its effect on the spinal cord and adjacent spinal nerves © 2015 Pearson Education, Inc.

9-5 The Shoulder Joint Shoulder Joint (glenohumeral joint) Allows more motion than any other joint and is the least stable joint and is supported by skeletal muscles, tendons, ligaments Ball-and-socket diarthrosis is between head of humerus and glenoid cavity of scapula Glenoid labrum is the deepens socket of glenoid cavity in fibrocartilage lining © 2015 Pearson Education, Inc.

9-5 The Shoulder Joint Shoulder Ligaments Shoulder Separation Glenohumeral Coracohumeral Coracoacromial Coracoclavicular Acromioclavicular Shoulder Separation Dislocation of the shoulder joint © 2015 Pearson Education, Inc.

9-5 The Shoulder Joint Shoulder Muscles (Rotator Cuff) Supraspinatus Infraspinatus Subscapularis Teres minor © 2015 Pearson Education, Inc.

9-5 The Shoulder Joint Shoulder Bursae Subacromial Subcoracoid Subdeltoid Subscapular © 2015 Pearson Education, Inc.

Figure 9-7a The Shoulder Joint. Acromioclavicular ligament Coracoacromial ligament Coracoclavicular ligaments Tendon of supraspinatus muscle Clavicle Acromion Articular capsule Coracoid process Subdeltoid bursa Scapula Synovial membrane Articular cartilages Humerus Joint cavity Glenoid labrum Articular capsule a Anterior view, frontal section

Figure 9-7b The Shoulder Joint. Ligaments Stabilizing the Shoulder Joint Subcoracoid bursa Tendon of biceps brachii muscle Clavicle Acromioclavicular ligament Subacromial bursa Coracoclavicular ligaments Muscles and Tendons of the Rotator Cuff Acromion Coracoacromial ligament Tendon of supraspinatus muscle Coracohumeral ligament (cut) Glenohumeral ligaments Tendon of infraspinatus muscle Subscapular bursa Teres minor muscle Glenoid cavity Glenoid labrum Subscapularis muscle Articular capsule Scapula b Lateral view of pectoral girdle

9-5 The Elbow Joint The Elbow Joint Is a stable hinge joint, with articulations involving humerus, radius, and ulna Humeroulnar joint Is the Largest joint, but trochlea of humerus and trochlear notch of ulna have limited movement Humeroradial joint Is the smaller joint Capitulum of humerus and head of radius © 2015 Pearson Education, Inc.

Figure 9-8a The Right Elbow Joint Showing Stabilizing Ligaments. Humerus Radial collateral ligament Radial tuberosity Antebrachial interosseous membrane Radius Ulna Capitulum Annular ligament (covering head and neck of radius) Lateral view a

9-5 The Elbow Joint Supporting Structures of the Elbow Biceps brachii muscle : Attached to radial tuberosity and controls elbow motion Elbow ligaments Radial collateral Annular Ulnar collateral © 2015 Pearson Education, Inc.

Figure 9-8b The Right Elbow Joint Showing Stabilizing Ligaments. Tendon of biceps brachii muscle Annular ligament Humerus Articular capsule Antebrachial interosseous membrane Medial epicondyle Ulnar collateral ligament Radius Ulna Olecranon of ulna b Medial view

9-6 The Hip Joint The Hip Joint (coxal joint): Are strong ball-and- socket diarthrosis, with wide range of motion Head of femur fits into hip joints. Ligaments of the Hip Joint Iliofemoral Pubofemoral Ischiofemoral Transverse acetabular Ligamentum teres © 2015 Pearson Education, Inc.

Figure 9-9a The Right Hip Joint. Iliofemoral ligament Articular cartilage Acetabular labrum Ligament of the femoral head Acetabulum Transverse acetabular ligament (spanning acetabular notch) Fat pad in acetabular fossa a A lateral view with the femur removed

Figure 9-9b The Right Hip Joint. Pubofemoral ligament Greater trochanter Iliofemoral ligament Lesser trochanter An anterior view b

Figure 9-9c The Right Hip Joint. Iliofemoral ligament Ischiofemoral ligament Greater trochanter Lesser trochanter Ischial tuberosity c A posterior view, showing additional ligaments that add strength to the capsule

9-6 The Knee Joint The Knee Joint A complicated hinge joint which transfers weight from femur to tibia Articulations of the knee joint 2 femur–tibia articulations at medial and lateral condyles 1 between patella and patellar surface of femur © 2015 Pearson Education, Inc.

9-6 The Knee Joint Seven Major Supporting Ligaments Patellar ligament (anterior) 2. & 3. Two popliteal ligaments (posterior) 4. & 5. Anterior and posterior cruciate ligaments (inside joint capsule) Tibial collateral ligament (medial) Fibular collateral ligament (lateral) © 2015 Pearson Education, Inc.

Figure 9-10a The Right Knee Joint. Quadriceps tendon Ligaments that Stabilize the Knee Joint Joint capsule Patella Patellar retinaculae Tibial collateral ligament Fibular collateral ligament Patellar ligament Fibula Tibia a Anterior view, superficial layer

Figure 9-10b The Right Knee Joint. Patellar surface Ligaments that Stabilize the Knee Joint Posterior cruciate ligament Lateral condyle Medial condyle Anterior cruciate ligament Tibial collateral ligament Menisci Medial Fibular collateral ligament Tibia Lateral Cut tendon of biceps femoris muscle Fibula b Deep anterior view, flexed

Figure 9-10c The Right Knee Joint. Plantaris muscle Gastrocnemius muscle, lateral head Gastrocnemius muscle, medial head Femur Ligaments that Stabilize the Knee Joint Bursa Tibial collateral ligament Joint capsule Fibular collateral ligament Popliteal ligaments Cut tendon of biceps femoris muscle Popliteus muscle Tibia Fibula c Posterior view, superficial layer

Figure 9-10d The Right Knee Joint. Femur Ligaments that Stabilize the Knee Joint Anterior cruciate ligament Fibular collateral ligament Posterior cruciate ligament Medial condyle Lateral condyle Menisci Lateral Medial Cut tendon Tibia Fibula d Deep posterior view, extended

Table 9-3 Joints of the Appendicular Skeleton (Part 1 of 2).

Table 9-3 Joints of the Appendicular Skeleton (Part 2 of 2).

9-7 Effects of Aging on Joints Degenerative Changes Rheumatism: A pain and stiffness of skeletal and muscular systems Arthritis: All forms of rheumatism that damage articular cartilages of synovial joints Osteoarthritis Caused by wear and tear of joint surfaces, or genetic factors affecting collagen formation Generally in people over age 60 © 2015 Pearson Education, Inc.

9-7 Effects of Aging on Joints Rheumatoid Arthritis An inflammatory condition which caused by infection, allergy, or autoimmune disease Involves the immune system Gouty Arthritis Occurs when crystals (uric acid or calcium salts) Form within synovial fluid and due to metabolic disorders © 2015 Pearson Education, Inc.

9-7 Effects of Aging on Joints Joint Immobilization Reduces flow of synovial fluid, it can cause arthritis symptoms and may treated by continuous passive motion or CPM (therapy) Bones and Aging Bone mass decreases and weaken, it may increases risk of hip fracture, hip dislocation, or pelvic fracture © 2015 Pearson Education, Inc.

9-8 Integration with Other Systems Bone Recycling Living bones maintain equilibrium between: Bone building (osteoblasts) And breakdown (osteoclasts) Factors Affecting Bone Strength Age Physical stress Hormone levels Calcium and phosphorus uptake and excretion Genetic and environmental factors © 2015 Pearson Education, Inc.

9-8 Integration with Other Systems Bones Support Body Systems Support and protect other systems Store fat, calcium, and phosphorus Manufacture cells for immune system Disorders in other body systems can cause: Bone tumors Osteoporosis Arthritis Rickets (vitamin D deficiency) © 2015 Pearson Education, Inc.

https://www.youtube.com/watch?v=nAAnhJKDZ7g © 2015 Pearson Education, Inc.

Quiz

Quiz 1-Most cartilage injuries tend to heal well by it selves _____ 2-The hip joint is referred to as a ball and socket joint._________ 3- What is another word for the term articulation?__________ 4- A ligament connects bone tissue to? ________

Quiz 1-F 2- T 3- joints 4-bone