Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
8 Articulations PowerPoint® Lecture Presentations prepared by Alexander G. Cheroske Mesa Community College at Red Mountain © 2011 Pearson Education, Inc. Section 1: Joint Design and Movement • Learning Outcomes • 8.1 Describe the basic structure of a synovial joint, and describe common accessory structures and their functions. • 8.2 Explain the relationship between structure and function for each type of synovial joint. • 8.3 Describe flexion/extension, abduction/adduction, and circumduction movements of the skeleton. • 8.4 Describe rotational and special movements of the skeleton. © 2011 Pearson Education, Inc. Section 1: Joint Design and Movement • Articulations (joints) • Where two bones interconnect • Bones are relatively inflexible so necessary to allow movement • Reflect compromise between need for strength versus need for mobility • Anatomical structure of each joint determines type and amount of movement possible • Categories from range of motion and subgroups from anatomical structure © 2011 Pearson Education, Inc. Section 1: Joint Design and Movement • Three functional categories 1. Synarthrosis (no movement) 2. Amphiarthrosis (little movement) 3. Diarthrosis (free movement) • • Synarthrotic and amphiarthrotic joints • Relatively simple structure • Direct connections between bones Diarthrotic joints • Complex in structure • Permit greatest range of motion © 2011 Pearson Education, Inc. Module 8.1: Synovial joints • Components of synovial joints • Articular cartilages • Resemble hyaline cartilages • Matrix contains more water comparatively • Have no perichondrium • Slick and smooth, so reduce friction • Are separated by thin film of synovial fluid © 2011 Pearson Education, Inc. Module 8.1: Synovial joints • Components of synovial joints (continued) • Synovial fluid • Similar in composition to ground substance in loose connective tissues • Produced at the synovial membrane • Circulates from areolar tissue to joint cavity • Percolates through articular cartilages • Total quantity is less than 3 mL © 2011 Pearson Education, Inc. Module 8.1: Synovial joints • Components of synovial joints (continued) • Joint capsule • Dense and fibrous • May be reinforced with accessory structures (tendons and ligaments) • Continuous with periosteum of each bone © 2011 Pearson Education, Inc. The structure of synovial joints Medullary cavity Components of Synovial Joints Periosteum Articular cartilage Joint capsule Synovial fluid Synovial membrane Spongy bone of epiphysis Compact bone Figure 8.1 © 2011 Pearson Education, Inc. 1 Module 8.1: Synovial joints • Functions of synovial fluid • Lubrication • With articular cartilage compression, synovial fluid is squeezed out and reduces friction between moving surfaces • Nutrient distribution • Provide nutrients and oxygen, as well as waste disposal for the chondrocytes of articular cartilages • Compression and reexpansion of articular cartilages pump synovial fluid in and out of cartilage matrix • Shock absorption • Distributes compression forces across articular surfaces and outward to joint capsule © 2011 Pearson Education, Inc. Module 8.1: Synovial joints • Accessory structures • Provide support and additional stability • Not all are included in every joint • Most are seen in the knee © 2011 Pearson Education, Inc. Module 8.1: Synovial joints • Accessory structures in knee • Tendons of quadriceps • Pass across joint • Limit movement • Provide mechanical support • Bursa (a pouch) • Small pocket filled with synovial fluid • Often form in areas where tendon or ligament rubs against other tissues • Reduce friction and act as shock absorbers © 2011 Pearson Education, Inc. Module 8.1: Synovial joints • Accessory structures in knee (continued) • Fat pads • Adipose tissue covered by synovial membrane • Protect articular cartilages • Act as packing material for joint • Meniscus (a crescent) • Pad of fibrous cartilage between bones of synovial joint • May subdivide joint cavity and affect fluid flow or allow variations in shapes of articular surfaces © 2011 Pearson Education, Inc. Module 8.1: Synovial joints • Accessory structures in knee (continued) • Accessory ligaments • Support, strengthen, and reinforce joint • Intrinsic ligaments • Localized thickening of joint capsule • Example: cruciate liagments of knee • Extrinsic ligaments • Separate from joint capsule • May pass inside (intracapsular) or outside (extracapsular) the joint capsule • Intracapsular example: cruciate ligaments • Extracapsular example: patellar ligament © 2011 Pearson Education, Inc. Accessory structures of complex synovial joints, as seen in a diagrammatic view of a sagittal section of the knee Tendon of the quadriceps muscles Patella Synovial membrane Accessory Structures Femur Joint capsule Bursa Fat pad Joint cavity Articular cartilage Meniscus Tibia Extracapsular ligament Intracapsular ligament Figure 8.1 © 2011 Pearson Education, Inc. 3 Module 8.1: Synovial joints • Mobility vs. strength in joints • Greater range of motion = weaker joint • Examples: • Synarthrosis (strongest type of joint, no movement) • Diarthrosis (far weaker but broad range of motion) • Dislocation (luxation) • Movement beyond normal range of motion • Articulating surfaces forced out of position • Can damage joint structures • No pain from inside joint but from nerves or surrounding structures © 2011 Pearson Education, Inc. Module 8.1 Review a. Define a joint dislocation (luxation). b. Describe the components of a synovial joint, and identify the functions of each. c. Why would improper circulation of synovial fluid lead to the degeneration of articular cartilages in the affected joint? © 2011 Pearson Education, Inc. Module 8.2: Types of motion and structural types of synovial joints • Types of motion permitted at synovial joints • Gliding • • Movement along two axes in one plane Angular motion • Movement along two axes in one plane with additional change in angle © 2011 Pearson Education, Inc. Module 8.2: Types of motion and structural types of synovial joints • Types of motion permitted at synovial joints (continued) • Circumduction • • • Special complex angular movement Proximal end of bone remains fixed while distal end can move in a circle (“trace circumference”) Rotation • Bone ends remain fixed and shaft rotates Animation: Synovial Joints: Movement © 2011 Pearson Education, Inc. The general types of movement at synovial joints Starting position Gliding Angular motion Circumduction Rotation Figure 8.2 © 2011 Pearson Education, Inc. 1 – 5 The anatomical types of synovial joints, with joint models and examples Types of Synovial Joints Models of Joint Motion Gliding joint Examples • Acromioclavicular and claviculosternal joints • Intercarpal and intertarsal joints • Vertebrocostal joints • Sacro-iliac joints Manubrium Hinge joint Humerus • Elbow joints • Knee joints • Ankle joints • Interphalangeal joints Ulna Pivot joint Atlas • Atlas/axis • Proximal radio-ulnar joints Axis Ellipsoid joint Scaphoid bone • Radiocarpal joints • Metacarpophalangeal joints 2–5 • Metatarsophalangeal joints Ulna Radius Saddle joint • First carpometacarpal joints Metacarpal bone of thumb Trapezium Ball-and-socket joint Scapula • Shoulder joints • Hip joints Humerus Figure 8.2 © 2011 Pearson Education, Inc. 6 Module 8.2 Review a. Identify the types of synovial joints based on the shapes of the articulating surfaces. b. What type of synovial joint permits the widest range of motion? c. Indicate the type of synovial joint for each of the following: shoulder, elbow, ankle, and thumb. © 2011 Pearson Education, Inc. Module 8.3: Specific angular movements • Flexion and extension • Usually applied to movements of long bones of limbs but also axial skeleton • Flexion • Anterior/posterior movement that reduces angle between articulating elements • Lateral flexion • • Dorsiflexion • • Vertebral column bending to the side Flexion at ankle joint and elevation of sole Plantar flexion (planta, sole) • © 2011 Pearson Education, Inc. Extension at ankle joint and elevation of heel Module 8.3: Specific angular movements • Flexion and extension (continued) • Extension • Anterior/posterior movement that increases angle between articulating elements • Hyperextension • Extension past anatomical position Animation: Foot Dorsiflexion: Plantar Flexion Animation: Elbow Flexion/Extension Animation: Wrist Flexion/Extension © 2011 Pearson Education, Inc. Flexion and extension Extension Flexion Hyperextension Lateral flexion Dorsiflexion (ankle flexion) Flexion Extension Plantar flexion (ankle extension) Flexion Hyperextension Figure 8.3 © 2011 Pearson Education, Inc. 1 Module 8.3: Specific angular movements • Abduction and Adduction • Always refers to movements of appendicular skeleton, not axial • Movements are usually toward or away from body midline • • For fingers or toes, movements are spreading digits apart or bringing them together Abduction (ab, from) • • Movement away from body longitudinal axis in frontal plane Adduction (ad, to) • Movement toward body longitudinal axis in frontal plane Animation: Humerus Abduction/Adduction © 2011 Pearson Education, Inc. Abduction and adduction Adduction Abduction Abduction Adduction Abduction Adduction Abduction Adduction Abduction Adduction Figure 8.3 © 2011 Pearson Education, Inc. 2 Module 8.3: Specific angular movements • Circumduction • Moving arm or thigh as if to draw a big circle at distal end of limb Animation: Wrist Circumduction Animation: Humerus Circumduction Animation: Synovial Joints: Angular Movement © 2011 Pearson Education, Inc. Module 8.3 Review a. When doing jumping jacks, which lower limb movements are necessary? b. Which movements are associated with hinge joints? c. Compare dorsiflexion to plantar flexion. © 2011 Pearson Education, Inc. Module 8.4: Rotation and special movements • Rotation • When applied to the trunk, described as left and right rotation • When applied to limbs • Medial rotation (internal or inward rotation) • • Anterior surface of limb toward trunk long axis Lateral rotation (external or outward rotation) • Anterior surface of limb away from trunk long axis Animation: Humerus Rotation © 2011 Pearson Education, Inc. Rotational movements Left rotation Right rotation Lateral (external) rotation Medial (internal) rotation Figure 8.4 © 2011 Pearson Education, Inc. 1 Module 8.4: Rotation and special movements • Rotation (continued) • Other special terms for rotation of forearm • • Pronation • Proximal end of radius rotates near ulna • Distal end rolls across anterior ulnar surface • Turns the wrist and hand from palm facing front to palm facing back Supination • Opposing movement • Palm is turned anteriorly Animation: Elbow Pronation/Supination © 2011 Pearson Education, Inc. Rotational movements Supination Pronation Figure 8.4 © 2011 Pearson Education, Inc. 1 Module 8.4: Rotation and special movements • Special movements • Opposition • • Movement of thumb toward palm surface or other fingers Protraction • • Movement forward in anterior plane Retraction • • Reverse of protraction Inversion (in, into + vertere, to turn) • • Twisting foot motion to turn sole inward Eversion (e, out) • Opposing movement to inversion © 2011 Pearson Education, Inc. Module 8.4: Rotation and special movements • Special movements (continued) • Depression • • Movement inferiorly Elevation • Movement superiorly Animation: Foot Inversion/Eversion Animation: Hand Opposition © 2011 Pearson Education, Inc. Special movements Opposition Eversion Retraction Protraction Inversion Depression Elevation Figure 8.4 © 2011 Pearson Education, Inc. 2 Module 8.4 Review a. Snapping your fingers involves what movement with the thumb and third metacarpophalangeal joint? b. What movements are made possible by the rotation of the radius head? c. What hand movements occur when wriggling into tight-fitting gloves? © 2011 Pearson Education, Inc. Section 2: Articulations • Learning Outcomes • 8.5 Describe the articulations between the vertebrae of the vertebral column. • 8.6 Describe the structure and function of the shoulder and hip joints. • 8.7 Describe the structure and function of the elbow and knee joints. • 8.8 CLINICAL MODULE Explain arthritis, and describe its effects on joint structure and function. © 2011 Pearson Education, Inc. Section 2: Articulations • Axial skeleton articulations • Typically are strong but very little movement • Appendicular skeleton articulations • Typically have extensive range of motion • Often weaker than axial articulations © 2011 Pearson Education, Inc. Joints of the Axial Skeleton Sutures of the skull Temporomandibular joint (temporal bone and mandible) Atlanto-occipital joint (occipital bone and atlas) and the atlanto-axial joint (C1–C2) Joints of the thoracic cage Intervertebral joints The lumbosacral joint, which attaches the last lumbar vertebra to the sacrum The sacrococcygeal and intercoccygeal joints, which structurally resemble simplified intervertebral joints Figure 8 Section 2 © 2011 Pearson Education, Inc. 1 Joints of the Appendicular Skeleton The sternoclavicular joint, the only articulation between the axial skeleton and the pectoral girdle and upper limb Shoulder joint The sacro-iliac joint, which firmly attaches the sacrum of the axial skeleton to the pelvic girdle of the appendicular skeleton Elbow joint Superior and inferior radio-ulnar joints Pubic symphysis Wrist joint Joints of the hand and fingers Hip joint Knee joint Ankle joint Joints of the foot and toes Figure 8 Section 2 © 2011 Pearson Education, Inc. 2 Module 8.5: Vertebral articulations • Vertebral articulations • Between superior and inferior articular processes of adjacent vertebrae • Gliding diarthrotic joints • Permit flexion and rotation • Adjacent vertebral bodies form symphyseal joints with intervertebral discs • Numerous ligaments attach bodies and processes of vertebrae to stabilize column © 2011 Pearson Education, Inc. Module 8.5: Vertebral articulations • Intervertebral discs • Composition • Anulus fibrosis • Tough outer layer of fibrous cartilage • Collagen fibers attach to adjacent vertebrae • Nucleus pulposus • Soft, elastic, gelatinous core • Provides resiliency and shock absorption • Account for ¼ length of vertebral column • Water loss from discs causes shortening of vertebral column with age and increases risk of disc injury © 2011 Pearson Education, Inc. An intervertebral disc Anulus fibrosus Nucleus pulposus Superior view Figure 8.5 © 2011 Pearson Education, Inc. 1 Module 8.5: Vertebral articulations • Primary vertebral ligaments • Ligamentum flavum • Connects adjacent vertebral laminae • Posterior longitudinal ligament • Connects posterior surfaces of adjacent vertebral bodies • Interspinous ligament • Connects spinous processes of adjacent vertebrae • Supraspinous ligament • Connects spinous processes from sacrum to C7 • Ligamentum nuchae from C7 to base of skull • Anterior longitudinal ligament • Connects anterior surfaces of adjacent vertebral bodies © 2011 Pearson Education, Inc. The ligaments attached to the bodies and processes of all vertebrae Primary Vertebral Ligaments Ligamentum flavum Intervertebral disc Anulus fibrosus Posterior longitudinal ligament Nucleus pulposus Spinal cord Interspinous ligament Spinal nerve Supraspinous ligament Posterior longitudinal ligament Anterior longitudinal ligament Lateral view Sectional view Figure 8.5 © 2011 Pearson Education, Inc. 2 Module 8.5: Vertebral articulations • Disorders of vertebral column • Slipped disc • Posterior longitudinal ligaments weaken causing more pressure on discs • Nucleus pulposus compresses, distorts anulus fibrosus • Disc bulges into vertebral canal (doesn’t actually slip) • Herniated disc • Nucleus pulposus breaks through anulus fibrosus • Spinal nerves are often affected © 2011 Pearson Education, Inc. A slipped disc, as seen in a lateral view T12 Normal intervertabral disc L1 Slipped disc L2 Figure 8.5 © 2011 Pearson Education, Inc. 3 A herniated disc, as seen in a superior view Compressed area of spinal nerve Nucleus pulposus of herniated disc Spinal nerve Spinal cord Anulus fibrosis Figure 8.5 © 2011 Pearson Education, Inc. 4 Module 8.5: Vertebral articulations • Disorders of vertebral column (continued) • Osteopenia (penia, lacking) • Inadequate ossification leading to loss of bone mass • Often occurs with age beginning between ages 30 and 40 • More severe in women than men • Osteoporosis (porosus, porous) • Bone loss sufficient to affect normal function © 2011 Pearson Education, Inc. The effects of osteoporosis on spongy bone Clinical scan of a compression fracture in a lumbar vertebra Figure 8.5 © 2011 Pearson Education, Inc. 5 The effects of osteoporosis on spongy bone Normal spongy bone SEM x 25 Spongy bone with osteoporosis SEM x 21 Figure 8.5 © 2011 Pearson Education, Inc. 5 Module 8.5 Review a. Identify the primary vertebral ligaments. b. Describe the nucleus pulposus and anulus fibrosus of an intervertebral disc. c. Compare a slipped disc with a herniated disc. © 2011 Pearson Education, Inc. Module 8.6: Shoulder and hip joints • Shoulder joint (glenohumeral joint) • Greatest range of motion of any joint • Most frequently dislocated joint • Demonstrates stability sacrificed for mobility • Most stability provided by surrounding skeletal muscles, associated tendons, and various ligaments • Ball-and-socket diarthrosis • Formed by head of humerus and glenoid cavity of scapula • Socket of glenoid cavity increased by fibrous-cartilaginous glenoid labrum (labrum, lip or edge) Animation: Scapula Clavicle Humerus © 2011 Pearson Education, Inc. Module 8.6: Shoulder and hip joints • Shoulder joint (continued) • Ligaments stabilizing the shoulder • Coracoclavicular ligaments • Acromioclavicular ligament • Coraco-acromial ligament • Coracohumeral ligament • Glenohumeral ligaments © 2011 Pearson Education, Inc. The shoulder joint (glenohumeral joint) Coracoid process Clavicle Acromion Ligaments Stabilizing the Shoulder Bursae Coracoclavicular ligaments Articular capsule Tendon of the biceps brachii muscle Acromioclavicular ligament Scapula Coraco-acromial ligament Coracohumeral ligament Glenohumeral ligaments Humerus Figure 8.6 © 2011 Pearson Education, Inc. 1 The structures within and surrounding the shoulder joint A frontal section of the shoulder joint A lateral view of the shoulder joint Subdeltoid Articular Coraco-acromial Coracoclavicular ligament ligaments bursa capsule Acromioclavicular ligament Clavicle Clavicle Tendon of supraspinatus muscle Tendon of infraspinatus muscle Tendon of biceps brachii muscle Articular cartilages Humerus Articular capsule Coracohumeral ligament (cut) Glenoid cavity Glenohumeral ligaments Scapula Subscapularis muscle Glenoid labrum Synovial membrane Frontal section Glenoid labrum Teres minor muscle Scapula Lateral view Figure 8.6 © 2011 Pearson Education, Inc. 2 – 3 Module 8.6: Shoulder and hip joints • Hip joint • Sturdy ball-and-socket joint • Although not directly aligned with weight distribution along femur shaft, which can produce fractures of femoral neck or intertrochanteric region • Permits flexion, extension, adduction, abduction, circumduction, and rotation • Formed by head of femur and acetabulum of hip bone • Socket of acetabulum increased by projecting rim of fibrous cartilage (acetabular labrum) • Articular capsule extends from lateral/inferior surfaces of pelvic girdle to intertrochanteric line and crest of femur © 2011 Pearson Education, Inc. The hip joint in lateral view Iliofemoral ligament Fibrous cartilage pad Acetabular labrum Acetabulum Fat pad Ligamentum teres (ligament of the femoral head) Transverse acetabular ligament Figure 8.6 © 2011 Pearson Education, Inc. 4 Module 8.6: Shoulder and hip joints • Hip joint (continued) • Reinforcing ligaments 1. Transverse acetabular ligament • 2. Crosses acetabular notch, filling gap in inferior border Ligamentum teres (teres, long and round) • Originates along transverse acetabular ligament and attached to fovea capitis 3. Pubofemoral ligament 4. Iliofemoral ligament 5. Ischiofemoral ligament Animation: Pelvic Girdle: Hip Femur © 2011 Pearson Education, Inc. The ligaments of the hip joint Reinforcing Ligaments Pubofemoral ligament Iliofemoral ligament Ischiofemoral ligament Greater trochanter Ischial tuberosity Posterior view Intertrochanteric line Lesser trochanter The ligaments of the hip joint in posterior view Anterior view The ligaments of the hip joint in anterior view Figure 8.6 © 2011 Pearson Education, Inc. 5 Module 8.6 Review a. Which tissues or structures provide most of the stability for the shoulder joint? b. At what site are the iliofemoral ligament, pubofemoral ligament, and ischiofemoral ligament located? c. A football player received a hard tackle to the upper surface of his shoulder, causing a shoulder separation. What bones and ligaments would be affected? © 2011 Pearson Education, Inc. Module 8.7: Elbow and knee joints • Elbow joint • Complex hinge joint involving humerus, radius, and ulna • Extremely strong and stable due to: 1. Bony surfaces of humerus and ulna interlock 2. Single, thick articular capsule surrounds both humeroulnar and proximal radio-ulnar joints 3. Articular capsule reinforced by strong ligaments • Severe stresses can still produce dislocations or other injuries • • Example: nursemaid’s elbow Muscles flexing elbow attach on anterior while those extending attach on the posterior © 2011 Pearson Education, Inc. Module 8.7: Elbow and knee joints • Elbow joint (continued) • Specific joints of the elbow • Humeroradial joint • • • Capitulum of humerus articulating with head of radius Humero-ulnar joint • Largest and strongest articulation • Trochlea of humerus articulates with trochlear notch of ulna • Shape of ulnar notch determines plane of movement • Shapes of olecranon fossa and olecranon limit degree of extension Proximal radio-ulnar joint is not part of elbow joint © 2011 Pearson Education, Inc. The elbow joint Humeroradial joint Anterior view Humerus Humeroulnar joint Radius Ulna Proximal radio-ulnar joint (not part of the elbow joint) Figure 8.7 © 2011 Pearson Education, Inc. 1 Module 8.7: Elbow and knee joints • Elbow joint (continued) • Reinforcing ligaments • Radial collateral ligament • • Ulnar collateral ligament • • Stabilizes lateral surface of joint Stabilizes medial surface of joint Annular ligament • Binds head of radius to ulna © 2011 Pearson Education, Inc. The elbow joint Humerus Posterior view Olecranon fossa Humeroulnar joint Ulna Olecranon Figure 8.7 © 2011 Pearson Education, Inc. 1 Module 8.7: Elbow and knee joints • Knee joint • Contains three separate articulations 1. Medial condyle of tibia to medial condyle of femur 2. Lateral condyle of tibia to lateral condyle of femur 3. Patella and patellar surface of femur • Permits flexion, extension, and very limited rotation Animation: Patella Tibia Fibula © 2011 Pearson Education, Inc. Module 8.7: Elbow and knee joints • Knee joint (continued) • External support • Quadriceps tendon to patella • • Fibular collateral ligament • • Medial support Popliteal ligaments • • Lateral support Tibial collateral ligament • • Continues as patellar ligament to anterior tibia Posterior support extending between femur and heads of tibia and fibula Tendons of several muscles that attach to femur and tibia © 2011 Pearson Education, Inc. The knee joint Superficial anterior view Femur Quadriceps tendon Joint capsule Fibular collateral ligament Bursa Patella Fibular collateral ligament Superficial posterior view Tibial collateral ligament Cut tendon of biceps femoris muscle Patellar ligament Popliteal ligaments Tibia Fibula Fibula Tibia Figure 8.7 © 2011 Pearson Education, Inc. 3 – 4 Module 8.7: Elbow and knee joints • Knee joint (continued) • Internal support • Cruciate ligaments limit anterior/posterior movement of femur and maintain alignment of condyles • • Anterior cruciate ligament (ACL) • At full extension, knee becomes “locked” (slight lateral rotation tightens ACL, and lateral meniscus forced between tibia and femur) • Opposite motion to “unlock” Posterior cruciate ligament (PCL) © 2011 Pearson Education, Inc. Module 8.7: Elbow and knee joints • Knee joint (continued) • Internal support (continued) • Medial and lateral menisci • Fibrous cartilage pads between tibial and femoral condyles • Act as cushions and provide lateral stability to joint © 2011 Pearson Education, Inc. The knee joint Deep anterior view, flexed Fibular collateral ligament Patellar surface of femur Lateral condyle PCL ACL ACL PCL Medial condyle Tibial collateral ligament Tibia Deep posterior view, extended Femur Lateral condyle Medial condyle Fibular collateral ligament Medial and lateral menisci Tibia Fibula Fibula Figure 8.7 © 2011 Pearson Education, Inc. 3 – 4 Module 8.7 Review a. Between the elbow and knee joints, which have menisci? b. What signs and symptoms would you expect in an individual who has damaged the menisci of the knee joint? © 2011 Pearson Education, Inc. CLINICAL MODULE 8.8: Disruption to normal joint function • Arthritis • Damage to articular cartilages but specific cause varies • Exposed surfaces change from slick, smooth-gliding to rough feltwork of collagen fibers increasing friction • Rheumatism (pain and stiffness affecting the skeletal and/or muscular systems) is often a symptom • Osteoarthritis • Also known as degenerative arthritis or degenerative joint disease • Generally affects individuals age 60 and older • • 25% of women, 15% of men Can result from cumulative wear and tear of joints or genetic factors affecting collagen formation © 2011 Pearson Education, Inc. Comparisons of normal articular cartilage with articular cartilage damaged by osteoarthritis Arthritic Joint Normal Joint Fibrous remains of the articular cartilage Articular cartilage Degenerating articular cartilage LM x 180 Arthroscopic view of normal cartilage LM x 180 Arthroscopic view of damaged cartilage Figure 8.8 © 2011 Pearson Education, Inc. 1 – 2 CLINICAL MODULE 8.8: Disruption to normal joint function • Visualizing problematic joints • Arthroscopic surgery • Optical fibers (arthroscope) inserted into joint through small incision without major surgery to visualize joint interior • If necessary, other instruments can be inserted through other incisions to permit surgery within view of arthroscope • Magnetic resonance imaging • Cost-effective and noninvasive viewing technique that allows examination of soft tissues around joint as well © 2011 Pearson Education, Inc. An arthroscopic view of the interior of the left knee, showing injuries to the anterior and posterior cruciate ligaments. PCL Femoral condyle ACL Meniscus Figure 8.8 © 2011 Pearson Education, Inc. 3 Figure 8.8 © 2011 Pearson Education, Inc. 4 CLINICAL MODULE 8.8: Disruption to normal joint function • Artificial joints • May be last resort if other solutions (exercise, physical therapy, drugs) for joint problems fail • Not as strong as natural joints, so most suitable for elderly • Typically have service life of about 10 years © 2011 Pearson Education, Inc. Figure 8.8 © 2011 Pearson Education, Inc. 5 CLINICAL MODULE 8.8 Review a. Compare rheumatism to osteoarthritis. b. Explain the use of an arthroscope. c. What can a person do to slow the progression of arthritis? © 2011 Pearson Education, Inc.