Ch 8. Joints. Joints Or articulations Sites where two bones meet 2 fundamental functions 1. Motility...

download Ch 8. Joints. Joints Or articulations Sites where two bones meet 2 fundamental functions 1. Motility 2. Hold skeleton together - Weakest part of skeleton.

If you can't read please download the document

Transcript of Ch 8. Joints. Joints Or articulations Sites where two bones meet 2 fundamental functions 1. Motility...

  • Slide 1
  • Ch 8. Joints
  • Slide 2
  • Joints Or articulations Sites where two bones meet 2 fundamental functions 1. Motility 2. Hold skeleton together - Weakest part of skeleton
  • Slide 3
  • Classification of Joints Classified by structure and function Structural material binding Fibrous Cartilaginous Synovial joints Function Amount of movement Synarthroses immovable Amphiarthroses slightly movable Diarthroses freely movable General fibrous = immobile Synovial freely movable Cartilaginous - both
  • Slide 4
  • Fibrous Joints Bones joined by fibrous tissue Dense fibrous connective tissue No joint cavity present Most are immovable 3 types 1.Sutures 2.Syndesmoses 3.gomphoses
  • Slide 5
  • Fibrous Joints 1. Sutures seams Only between bones of skull Rigid slices knit bone together During middle age ossifies closed sutures synostoses Immobile = protection
  • Slide 6
  • Figure 8.1a Dense fibrous connective tissue Suture line (a) Suture Joint held together with very short, interconnecting fibers, and bone edges interlock. Found only in the skull.
  • Slide 7
  • Fibrous Joints 2. Syndesmoses Bones connected by ligaments Only cords or bands of fibrous tissue Amount of movement depends on length of connecting fibers
  • Slide 8
  • Figure 8.1b Fibula Tibia Ligament (b) Syndesmosis Joint held together by a ligament. Fibrous tissue can vary in length, but is longer than in sutures.
  • Slide 9
  • Fibrous Joints 3. Gomphoses Peg in socket fibrous joint Tooth joint Teeth embedded in sockets periodontal ligament
  • Slide 10
  • Figure 8.1c Root of tooth Socket of alveolar process Periodontal ligament (c) Gomphosis Peg in socket fibrous joint. Periodontal ligament holds tooth in socket.
  • Slide 11
  • Cartilaginous Joints Unit articulating bones Lack joint cavity Not highly mobile 2 types 1.Synchondroses 2.Symphyses
  • Slide 12
  • Cartilaginous Joints 1. Synchondroses Bones united by bar or plate of hyaline cartilage Epiphyseal plates in long bones of children Costal cartilage of first rib
  • Slide 13
  • Figure 8.1c Root of tooth Socket of alveolar process Periodontal ligament (c) Gomphosis Peg in socket fibrous joint. Periodontal ligament holds tooth in socket.
  • Slide 14
  • Cartilaginous Joints 2. Symphyses growing together Intervening pad or plate of fibrocartilage Compress able and resilience Amphiarthrotic joints Designed for strength and flexibility
  • Slide 15
  • Figure 8.2b Fibrocartilaginous intervertebral disc Pubic symphysis Body of vertebra Hyaline cartilage (b) Symphyses Bones united by fibrocartilage
  • Slide 16
  • Synovial Joints joint eggs Articulating bones are separated by a fluid filled joint cavity Freedom of movement Freely moveable diarthroses
  • Slide 17
  • Synovial Joints General Structure 6 distinguishing characteristics: 1. Articular Cartilage glassy smooth hyaline articular cartilage Thin, spongy cushions absorb compression 2. Joint (Synovial) Cavity joint cavity potential space with a small amount of synovial fluid 3. Articular Capsule 2 layered articular capsule or joint capsule Inner synovial membrane loose CT 4. Synovial Fluid occupies all free space Derived by filtration Viscous, egg white consistency Slippery weight bearing film reduces friction
  • Slide 18
  • Synovial Joints General Structure 5. Reinforcing Ligaments band like ligaments Usually capsular or intrinsic ligaments thickened parts of fibrous capsule Outside capsule distinct extra- capsular ligaments Deep to it intracapsular ligaments 6. Nerves and blood vessels richly supplied with sensory nerve fibers Some detect pain Most monitor joint positions and stretch Richly supplied with capillary beds produce filtrate
  • Slide 19
  • Synovial Joints General Structure Other Components Cushioning fatty pads Articular discs menisci wedges of fibrocartilage
  • Slide 20
  • Figure 8.3 Periosteum Ligament Fibrous capsule Synovial membrane Joint cavity (contains synovial fluid) Articular (hyaline) cartilage Articular capsule
  • Slide 21
  • Brusae And Tendon Sheaths Associated with joints Bags of lubricants Ball bearings reduce friction Bursae flattened fibrous sacs Thin film of synovial fluid Occur where ligaments, muscles, skin, tendons, or bones rub together Tendon Sheath Elongated bursae wraps completely around tendon subjected to friction Where several tendons crowded together
  • Slide 22
  • Figure 8.4b Coracoacromial ligament Subacromial bursa Cavity in bursa containing synovial fluid Bursa rolls and lessens friction. Humerus head rolls medially as arm abducts. (b) Enlargement of (a), showing how a bursa eliminates friction where a ligament (or other structure) would rub against a bone Humerus resting Humerus moving
  • Slide 23
  • Stability of Synovial Joints Stabilized so do not dislocate Stability depends on 1.Shape of articular surfaces 2.Number and position of ligaments 3.Muscle tone
  • Slide 24
  • Stability of Synovial Joints 1. Articular Surfaces Shapes determine movements possible Minor role in stability Many joints shallow sockets non- complementary articulating surfaces When large socket deep stability vastly improved
  • Slide 25
  • Stability of Synovial Joints 2. Ligaments more ligaments stronger Brace joints 3. Muscle Tone muscle tendons cross joints Tendons taught at all times Muscle tone low levels of contractile activity in relaxed muscles keep them muscles healthy and ready to react
  • Slide 26
  • Movements Allowed by Synovial Joints Muscle origin attached to immobile or less movable bone Insertion attached to movable bone Muscle contract insertion moves towards origin Nonaxial movement slipping movements only no axis Uniaxial movements movement in 1 plane Biaxial movement movement in 2 planes Multiaxial movement movement in or around all 3 planes and axes
  • Slide 27
  • 3 General Types of Movement 1.Gliding 2.Angular Movements 3.Rotations
  • Slide 28
  • 1. Gliding Simplest One flat bone surface slides over another Back and forth, side to side No angulations or rotation Intercarpal and intercostal joints
  • Slide 29
  • Figure 8.5a Gliding (a) Gliding movements at the wrist
  • Slide 30
  • 2. Angular Increase or decrease angle between 2 bones Any plane of the body Include flexion, extension, hyperextension, abduction, adduction and circumduction
  • Slide 31
  • Figure 8.5b (b) Angular movements: flexion, extension, and hyperextension of the neck HyperextensionExtension Flexion
  • Slide 32
  • 2. Angular A. Flexion Bending movement Usually along sagittal plane Decrease angle of joint Head toward chest
  • Slide 33
  • Figure 8.5c Hyperextension Flexion Extension (c) Angular movements: flexion, extension, and hyperextension of the vertebral column
  • Slide 34
  • 2. Angular B. Extension Reverse of flexion Occurs at same joints Movement along sagittal plane Increase the angle Straightens a flexed limb or body part Ex. Straightening the knee Hyperextension extension beyond anatomical position
  • Slide 35
  • Figure 8.5c Hyperextension Flexion Extension (c) Angular movements: flexion, extension, and hyperextension of the vertebral column
  • Slide 36
  • 2. Angular C. Abduction moving away Movement of a limb away from the midline Along frontal plane
  • Slide 37
  • Figure 8.5e Abduction Adduction (e) Angular movements: abduction, adduction, and circumduction of the upper limb at the shoulder Circumduction
  • Slide 38
  • 2. Angular D. Adduction moving toward Opposite abduction Movement of a limb toward body midline
  • Slide 39
  • Figure 8.5e Abduction Adduction (e) Angular movements: abduction, adduction, and circumduction of the upper limb at the shoulder Circumduction
  • Slide 40
  • 2. Angular E. Circumduction Moving limb so it describes a cone in space Distal end of limb moves in a circle
  • Slide 41
  • 3. Rotation Turning of bone around its long axis 1 st 2 cervical vertebrae Hip, shoulder Towards or away from midline
  • Slide 42
  • Figure 8.5f Lateral rotation Medial rotation Rotation (f) Rotation of the head, neck, and lower limb
  • Slide 43
  • Special Movements Do not fit into any of other categories Supination turning backwards radius around ulna Pronation turning forward radius around ulna
  • Slide 44
  • Figure 8.6a Supination (radius and ulna are parallel) (a) Pronation (P) and supination (S) Pronation (radius rotates over ulna)
  • Slide 45
  • Special Movements Dorsiflexion increase and decrease movement of foot, foot superior approaches shin Plantar Flexion pointing toes
  • Slide 46
  • Figure 8.6b Dorsiflexion Plantar flexion Dorsiflexion Plantar flexion (b) Dorsiflexion and plantar flexion
  • Slide 47
  • Special Movements Inversion sole of foot turns medially Eversion sole face laterally
  • Slide 48
  • Figure 8.6c Eversion Inversion (c) Inversion and eversion
  • Slide 49
  • Special Movements Protraction anterior movement in transverse plane Retraction posterior movement in a transverse plane
  • Slide 50
  • Figure 8.6d Protraction of mandible Retraction of mandible (d) Protraction and retraction
  • Slide 51
  • Special Movements Elevation lift body part superiorly Depression moving elevated part inferiorly
  • Slide 52
  • Figure 8.6e Elevation of mandible Depression of mandible (e) Elevation and depression
  • Slide 53
  • Special Movements Opposition joint between metacarpal 1 and trapezium Movement of thumb
  • Slide 54
  • Figure 8.6f (f) Opposition Opposition
  • Slide 55
  • Types of Synovial Joints 6 categories 1. Plane Joint Flat Allow only short non-axial gliding movement No rotation Non-axial plane joints
  • Slide 56
  • Figure 8.7a a b c d e f Nonaxial Uniaxial Biaxial Multiaxial a Plane joint (intercarpal joint)
  • Slide 57
  • Types of Synovial Joints 2. Hinge Joints Cylindrical end of bone conforms to trough shaped surface Motion single plane Resembles mechanical hinge Permit flexion and extension only
  • Slide 58
  • Figure 8.7b b Hinge joint (elbow joint) a b c d e f Nonaxial Uniaxial Biaxial Multiaxial
  • Slide 59
  • Types of Synovial Joints 3. Pivot Joints Rounded end of bone conforms to sleeve or ring composed of bone Uniaxial rotation Atlas and dens joint Ex. Head side to side
  • Slide 60
  • Figure 8.7c c Pivot joint (proximal radioulnar joint) a b c d e f Nonaxial Uniaxial Biaxial Multiaxial
  • Slide 61
  • Types of Synovial Joints 4. Condyloid Joint Also ellipsoidal joint Fits into complete depressions in another articulating surfaces oval Angular motion Ex. Radiocarpal joints
  • Slide 62
  • Figure 8.7d d Condyloid joint (metacarpophalangeal joint) a b c d e f Nonaxial Uniaxial Biaxial Multiaxial
  • Slide 63
  • Types of Synovial Joints 5. Saddle Joints Like condyloid joint but allow greater motion Both concave and convex areas Shaped like a saddle Carpometacarpal joint of thumb
  • Slide 64
  • Figure 8.7e e Saddle joint (carpometacarpal joint of thumb) a b c d e f Nonaxial Uniaxial Biaxial Multiaxial
  • Slide 65
  • Types of Synovial Joints 6. Ball and Sockets Spherical or hemispherical head of one bone articulates with cup like socket of another Multiaxial and most freely moving synovial Universal movement shoulder and hip
  • Slide 66
  • Figure 8.7f f Ball-and-socket joint (shoulder joint) a b c d e f Nonaxial Uniaxial Biaxial Multiaxial
  • Slide 67
  • Synovial Joints- Knee Joint Largest, most complex joint of body Three joints surrounded by a single joint cavity: Femoropatellar joint: Plane joint Allows gliding motion during knee flexion Lateral and medial tibiofemoral joints between the femoral condyles and the C-shaped lateral and medial menisci (semilunar cartilages) of the tibia Allow flexion, extension, and some rotation when knee is partly flexed
  • Slide 68
  • Figure 8.8a (a) Sagittal section through the right knee joint Femur Tendon of quadriceps femoris Suprapatellar bursa Patella Subcutaneous prepatellar bursa Synovial cavity Lateral meniscus Posterior cruciate ligament Infrapatellar fat pad Deep infrapatellar bursa Patellar ligament Articular capsule Lateral meniscus Anterior cruciate ligament Tibia
  • Slide 69
  • Figure 8.8b (b) Superior view of the right tibia in the knee joint, showing the menisci and cruciate ligaments Medial meniscus Articular cartilage on medial tibial condyle Anterior cruciate ligament Articular cartilage on lateral tibial condyle Lateral meniscus Posterior cruciate ligament
  • Slide 70
  • Synovial Joints- Knee Joint At least 12 associated bursae Capsule is reinforced by muscle tendons: E.g., quadriceps and semimembranosus tendons Joint capsule is thin and absent anteriorly Anteriorly, the quadriceps tendon gives rise to: Lateral and medial patellar retinacula Patellar ligament
  • Slide 71
  • Figure 8.8c Quadriceps femoris muscle Tendon of quadriceps femoris muscle Patella Lateral patellar retinaculum Medial patellar retinaculum Tibial collateral ligament Tibia Fibular collateral ligament Fibula (c) Anterior view of right knee Patellar ligament
  • Slide 72
  • Synovial Joints- Knee Joint Capsular and extracapsular ligaments Help prevent hyperextension Intracapsular ligaments: Anterior and posterior cruciate ligaments Prevent anterior-posterior displacement Reside outside the synovial cavity
  • Slide 73
  • Figure 8.8d Articular capsule Oblique popliteal ligament Lateral head of gastrocnemius muscle Fibular collateral ligament Arcuate popliteal ligament Tibia Femur Medial head of gastrocnemius muscle Tendon of semimembranosus muscle (d) Posterior view of the joint capsule, including ligaments Popliteus muscle (cut) Tendon of adductor magnus Bursa Tibial collateral ligament
  • Slide 74
  • Synovial Joint Shoulder Joint Ball-and-socket joint: head of humerus and glenoid fossa of the scapula Stability is sacrificed for greater freedom of movement
  • Slide 75
  • Figure 8.10a PLAY Animation: Rotatable shoulder Acromion of scapula Synovial membrane Fibrous capsule Hyaline cartilage Coracoacromial ligament Subacromial bursa Fibrous articular capsule Tendon sheath Tendon of long head of biceps brachii muscle Synovial cavity of the glenoid cavity containing synovial fluid Humerus (a) Frontal section through right shoulder joint
  • Slide 76
  • Synovial Joint Shoulder Joint Reinforcing ligaments: Coracohumeral ligamenthelps support the weight of the upper limb Three glenohumeral ligamentssomewhat weak anterior reinforcements
  • Slide 77
  • Synovial Joint Shoulder Joint Reinforcing muscle tendons: Tendon of the long head of biceps: Travels through the intertubercular groove Secures the humerus to the glenoid cavity Four rotator cuff tendons encircle the shoulder joint: Subscapularis Supraspinatus Infraspinatus Teres minor
  • Slide 78
  • Figure 8.10c Acromion Coracoacromial ligament Subacromial bursa Coracohumeral ligament Greater tubercle of humerus Transverse humeral ligament Tendon sheath Tendon of long head of biceps brachii muscle Articular capsule reinforced by glenohumeral ligaments Subscapular bursa Tendon of the subscapularis muscle Scapula Coracoid process (c) Anterior view of right shoulder joint capsule
  • Slide 79
  • Figure 8.10d Acromion Coracoid process Articular capsule Glenoid cavity Glenoid labrum Tendon of long head of biceps brachii muscle Glenohumeral ligaments Tendon of the subscapularis muscle Scapula PosteriorAnterior (d) Lateral view of socket of right shoulder joint, humerus removed
  • Slide 80
  • Synovial Joint Elbow Joint Radius and ulna articulate with the humerus Hinge joint formed mainly by trochlear notch of ulna and trochlea of humerus Flexion and extension only
  • Slide 81
  • Figure 8.11a Articular capsule Synovial membrane Synovial cavity Articular cartilage Coronoid process Tendon of brachialis muscle Ulna Humerus Fat pad Tendon of triceps muscle Bursa Trochlea Articular cartilage of the trochlear notch (a) Median sagittal section through right elbow (lateral view)
  • Slide 82
  • Synovial Joint Elbow Joint Anular ligamentsurrounds head of radius Two capsular ligaments restrict side-to-side movement: Ulnar collateral ligament Radial collateral ligament
  • Slide 83
  • Figure 8.11b Humerus Lateral epicondyle Articular capsule Radial collateral ligament Olecranon process Anular ligament Radius Ulna (b) Lateral view of right elbow joint
  • Slide 84
  • PLAY Animation: Rotatable elbow Figure 8.11d Articular capsule Anular ligament Coronoid process (d) Medial view of right elbow Radius Humerus Medial epicondyle Ulnar collateral ligament Ulna
  • Slide 85
  • Synovial Joint - Hip (Coxal) Joint Ball-and-socket joint Head of the femur articulates with the acetabulum Good range of motion, but limited by the deep socket Acetabular labrumenhances depth of socket
  • Slide 86
  • Figure 8.12a Articular cartilage Coxal (hip) bone Ligament of the head of the femur (ligamentum teres) Synovial cavity Articular capsule Acetabular labrum Femur (a) Frontal section through the right hip joint Reinforcing ligaments: Iliofemoral ligament Pubofemoral ligament Ischiofemoral ligament Ligamentum teres
  • Slide 87
  • Synovial Joint - Hip (Coxal) Joint Reinforcing ligaments: Iliofemoral ligament Pubofemoral ligament Ischiofemoral ligament Ligamentum teres
  • Slide 88
  • PLAY Animation: Rotatable hip Figure 8.12c Ischium Iliofemoral ligament Ischiofemoral ligament Greater trochanter of femur (c) Posterior view of right hip joint, capsule in place
  • Slide 89
  • Figure 8.12d Anterior inferior iliac spine Iliofemoral ligament Pubofemoral ligament Greater trochanter (d) Anterior view of right hip joint, capsule in place
  • Slide 90
  • Temporomandibular Joint (TMJ) Mandibular condyle articulates with the temporal bone Two types of movement Hingedepression and elevation of mandible Glidinge.g. side-to-side (lateral excursion) grinding of teeth Most easily dislocated joint in the body
  • Slide 91
  • Figure 8.13a Zygomatic process Mandibular fossa Articular tubercle Infratemporal fossa External acoustic meatus Articular capsule Ramus of mandible Lateral ligament (a) Location of the joint in the skull
  • Slide 92
  • Figure 8.13b Articular capsule Mandibular fossa Articular disc Articular tubercle Superior joint cavity Inferior joint cavity Mandibular condyle Ramus of mandible Synovial membranes (b) Enlargement of a sagittal section through the joint
  • Slide 93
  • Figure 8.13c Lateral excursion: lateral (side-to-side) movements of the mandible Outline of the mandibular fossa Superior view
  • Slide 94
  • Common Joint Injuries Sprains The ligaments are stretched or torn Partial tears slowly repair themselves Complete ruptures require prompt surgical repair Cartilage tears Due to compression and shear stress Fragments may cause joint to lock or bind Cartilage rarely repairs itself Repaired with arthroscopic surgery
  • Slide 95
  • Figure 8.14 Torn meniscus
  • Slide 96
  • Common Joint Injuries Dislocations (luxations) Occur when bones are forced out of alignment Accompanied by sprains, inflammation, and joint immobilization Caused by serious falls or playing sports Subluxationpartial dislocation of a joint
  • Slide 97
  • Homeostatic Imbalances Bursitis An inflammation of a bursa, usually caused by a blow or friction Treated with rest and ice and, if severe, anti- inflammatory drugs Tendonitis Inflammation of tendon sheaths typically caused by overuse Symptoms and treatment similar to bursitis
  • Slide 98
  • Homeostatic Imbalances Arthritis >100 different types of inflammatory or degenerative diseases that damage joints Most widespread crippling disease in the U.S. Symptoms; pain, stiffness, and swelling of a joint Acute forms: caused by bacteria, treated with antibiotics Chronic forms: osteoarthritis, rheumatoid arthritis, and gouty arthritis
  • Slide 99
  • Homeostatic Imbalances Osteoarthritis (OA) Common, irreversible, degenerative (wear-and-tear) arthritis 85% of all Americans develop OA, more women than men Probably related to the normal aging process More cartilage is destroyed than replaced in badly aligned or overworked joints Exposed bone ends thicken, enlarge, form bone spurs, and restrict movement Treatment: moderate activity, mild pain relievers, capsaicin creams, glucosamine and chondroitin sulfate
  • Slide 100
  • Homeostatic Imbalances Rheumatoid Arthritis (RA) Chronic, inflammatory, autoimmune disease of unknown cause Usually arises between age 40 and 50, but may occur at any age; affects 3 times as many women as men Signs and symptoms include joint pain and swelling (usually bilateral), anemia, osteoporosis, muscle weakness, and cardiovascular problems
  • Slide 101
  • Homeostatic Imbalances Rheumatoid Arthritis (RA) cont RA begins with synovitis of the affected joint Inflammatory blood cells migrate to the joint, release inflammatory chemicals Inflamed synovial membrane thickens into a pannus Pannus erodes cartilage, scar tissue forms, articulating bone ends connect (ankylosis)
  • Slide 102
  • Figure 8.15
  • Slide 103
  • Homeostatic Imbalances Rheumatoid Arthritis (RA) Treatment - Conservative therapy: aspirin, long-term use of antibiotics, and physical therapy Progressive treatment: anti-inflammatory drugs or immunosuppressants New biological response modifier drugs neutralize inflammatory chemicals
  • Slide 104
  • Homeostatic Imbalances Gouty Arthritis Deposition of uric acid crystals in joints and soft tissues, followed by inflammation More common in men Typically affects the joint at the base of the great toe In untreated gouty arthritis, the bone ends fuse and immobilize the joint Treatment: drugs, plenty of water, avoidance of alcohol
  • Slide 105
  • Homeostatic Imbalances Lyme Disease Caused by bacteria transmitted by the bites of ticks Symptoms: skin rash, flu-like symptoms, and foggy thinking May lead to joint pain and arthritis Treatment: antibiotics
  • Slide 106
  • Developmental Aspects By embryonic week 8, synovial joints resemble adult joints A joints size, shape, and flexibility are modified by use Advancing years take their toll on joints: Ligaments and tendons shorten and weaken Intervertebral discs become more likely to herniate Most people in their 70s have some degree of OA Exercise that coaxes joints through their full range of motion is key to postponing joint problems