Plane JointPlane Joint

Plane jointsPlane joints Articular surfaces are Articular surfaces are

essentially flatessentially flat Allow only slipping or Allow only slipping or

gliding movementsgliding movements Only examples of Only examples of

nonaxial jointsnonaxial joints

Figure 8.7a

Types of Synovial JointsTypes of Synovial Joints

Hinge jointsHinge joints Cylindrical projections of one bone fits into a Cylindrical projections of one bone fits into a

trough-shaped surface on anothertrough-shaped surface on another Motion is along a single planeMotion is along a single plane Uniaxial joints permit flexion and extension onlyUniaxial joints permit flexion and extension only Examples: elbow and interphalangeal jointsExamples: elbow and interphalangeal joints

Hinge JointsHinge Joints

Figure 8.7b

Pivot JointsPivot Joints

Rounded end of one bone protrudes into a Rounded end of one bone protrudes into a “sleeve,” or ring, composed of bone (and “sleeve,” or ring, composed of bone (and possibly ligaments) of anotherpossibly ligaments) of another

Only uniaxial movement allowedOnly uniaxial movement allowed Examples: joint between the axis and the dens, Examples: joint between the axis and the dens,

and the proximal radioulnar jointand the proximal radioulnar joint

Pivot JointsPivot Joints

Figure 8.7c

Condyloid or Ellipsoidal JointsCondyloid or Ellipsoidal Joints

Oval articular surface of one bone fits into a Oval articular surface of one bone fits into a complementary depression in anothercomplementary depression in another

Both articular surfaces are ovalBoth articular surfaces are oval Biaxial joints permit all angular motionsBiaxial joints permit all angular motions Examples: radiocarpal (wrist) joints, and Examples: radiocarpal (wrist) joints, and

metacarpophalangeal (knuckle) jointsmetacarpophalangeal (knuckle) joints

Condyloid or Ellipsoidal JointsCondyloid or Ellipsoidal Joints

Figure 8.7d

Saddle JointsSaddle Joints

Similar to condyloid joints but allow greater Similar to condyloid joints but allow greater movementmovement

Each articular surface has both a concave and Each articular surface has both a concave and a convex surfacea convex surface

Example: carpometacarpal joint of the thumbExample: carpometacarpal joint of the thumb

Saddle JointsSaddle Joints

Figure 8.7e

Ball-and-Socket JointsBall-and-Socket Joints

A spherical or hemispherical head of one bone A spherical or hemispherical head of one bone articulates with a cuplike socket of anotherarticulates with a cuplike socket of another

Multiaxial joints permit the most freely Multiaxial joints permit the most freely moving synovial jointsmoving synovial joints

Examples: shoulder and hip jointsExamples: shoulder and hip joints

Ball-and-Socket JointsBall-and-Socket Joints

Figure 8.7f

Synovial Joints: KneeSynovial Joints: Knee

Largest and most complex joint of the bodyLargest and most complex joint of the body Allows flexion, extension, and some rotationAllows flexion, extension, and some rotation Three joints in one surrounded by a single Three joints in one surrounded by a single

joint cavityjoint cavity Femoropatellar jointFemoropatellar joint Lateral and medial tibiofemoral jointsLateral and medial tibiofemoral joints

Synovial Joints: Knee Ligaments Synovial Joints: Knee Ligaments and Tendons – Anterior Viewand Tendons – Anterior View

Tendon of the Tendon of the quadriceps femoris quadriceps femoris musclemuscle

Lateral and medial Lateral and medial patellar retinaculapatellar retinacula

Fibular and tibial Fibular and tibial collateral ligamentscollateral ligaments

Patellar ligamentPatellar ligament

Figure 8.8c

Synovial Joints: Knee – Synovial Joints: Knee – Other Supporting StructuresOther Supporting Structures

Anterior cruciate ligamentAnterior cruciate ligament Posterior cruciate ligamentPosterior cruciate ligament Medial meniscus (semilunar cartilage)Medial meniscus (semilunar cartilage) Lateral meniscusLateral meniscus

Synovial Joints: Knee – Synovial Joints: Knee – Other Supporting StructuresOther Supporting Structures

Figure 8.8b

Synovial Joints: Knee – Synovial Joints: Knee – Posterior Superficial ViewPosterior Superficial View

Adductor magnus Adductor magnus tendontendon

Articular capsuleArticular capsule Oblique popliteal Oblique popliteal

ligamentligament Arcuate popliteal Arcuate popliteal

ligamentligament Semimembranosus Semimembranosus

tendontendon

Figure 8.8e

Synovial Joints: Shoulder Synovial Joints: Shoulder (Glenohumeral)(Glenohumeral)

Ball-and-socket joint in which stability is Ball-and-socket joint in which stability is sacrificed to obtain greater freedom of sacrificed to obtain greater freedom of movementmovement

Head of humerus articulates with the glenoid Head of humerus articulates with the glenoid fossa of the scapulafossa of the scapula

Synovial Joints: ElbowSynovial Joints: Elbow

Hinge joint that allows flexion and extension Hinge joint that allows flexion and extension onlyonly

Radius and ulna articulate with the humerusRadius and ulna articulate with the humerus

Synovial Joints: ElbowSynovial Joints: Elbow

Annular ligamentAnnular ligament Ulnar collateral Ulnar collateral

ligamentligament Radial collateral Radial collateral

ligamentligament

Figure 8.10a

Synovial Joints: ElbowSynovial Joints: Elbow

Figure 8.10b

Synovial Joints: ElbowSynovial Joints: Elbow

Figure 8.10d

Synovial Joints: Shoulder Synovial Joints: Shoulder StabilityStability

Weak stability is maintained by:Weak stability is maintained by: Thin, loose joint capsuleThin, loose joint capsule Four ligaments – coracohumeral, and three Four ligaments – coracohumeral, and three

glenohumeralglenohumeral Tendon of the long head of biceps, which travels Tendon of the long head of biceps, which travels

through the intertubercular groove and secures the through the intertubercular groove and secures the humerus to the glenoid cavityhumerus to the glenoid cavity

Rotator cuff (four tendons) that encircles the Rotator cuff (four tendons) that encircles the shoulder joint and blends with the articular capsuleshoulder joint and blends with the articular capsule

Synovial Joints: Shoulder StabilitySynovial Joints: Shoulder Stability

Figure 8.11a

Synovial Joints: Shoulder StabilitySynovial Joints: Shoulder Stability

Figure 8.11b

Synovial Joints: Hip (Coxal) Synovial Joints: Hip (Coxal) JointJoint

Ball-and-socket jointBall-and-socket joint Head of the femur articulates with the Head of the femur articulates with the

acetabulumacetabulum Good range of motion, but limited by the deep Good range of motion, but limited by the deep

socket and strong ligamentssocket and strong ligaments

Synovial Joints: Hip StabilitySynovial Joints: Hip Stability

Acetabular labrumAcetabular labrum Iliofemoral Iliofemoral

ligamentligament Pubofemoral Pubofemoral

ligamentligament Ischiofemoral Ischiofemoral

ligamentligament Ligamentum teresLigamentum teres

Figure 8.12a

Synovial Joints: Hip StabilitySynovial Joints: Hip Stability

Figure 8.12c, d

Temporomandibular Joint Temporomandibular Joint (TMJ)(TMJ)

Mandibular condyle articulate with the Mandibular condyle articulate with the temporal bonetemporal bone

Two types of movementTwo types of movement Hinge – depression and elevation of mandibleHinge – depression and elevation of mandible Side to side – (lateral excursion) grinding of teethSide to side – (lateral excursion) grinding of teeth

Temporomandibular JointTemporomandibular Joint

Figure 8.13a, b

SprainsSprains

The ligaments reinforcing a joint are stretched The ligaments reinforcing a joint are stretched or tornor torn

Partially torn ligaments slowly repair Partially torn ligaments slowly repair themselvesthemselves

Completely torn ligaments require prompt Completely torn ligaments require prompt surgical repairsurgical repair

Cartilage InjuriesCartilage Injuries

The snap and pop of overstressed cartilageThe snap and pop of overstressed cartilage Common aerobics injuryCommon aerobics injury Repaired with arthroscopic surgeryRepaired with arthroscopic surgery

DislocationsDislocations

Occur when bones are forced out of alignmentOccur when bones are forced out of alignment Usually accompanied by sprains, Usually accompanied by sprains,

inflammation, and joint immobilizationinflammation, and joint immobilization Caused by serious falls and are common sports Caused by serious falls and are common sports

injuriesinjuries Subluxation – partial dislocation of a jointSubluxation – partial dislocation of a joint

Inflammatory and Degenerative Inflammatory and Degenerative ConditionsConditions

BursitisBursitis An inflammation of a bursa, usually caused by a An inflammation of a bursa, usually caused by a

blow or frictionblow or friction Symptoms are pain and swellingSymptoms are pain and swelling Treated with anti-inflammatory drugs; excessive Treated with anti-inflammatory drugs; excessive

fluid may be aspirated, ultimately surgery will be fluid may be aspirated, ultimately surgery will be neededneeded

Inflammatory and Degenerative Inflammatory and Degenerative ConditionsConditions

TendonitisTendonitis Inflammation of tendon sheaths typically caused Inflammation of tendon sheaths typically caused

by overuseby overuse Symptoms and treatment are similar to bursitisSymptoms and treatment are similar to bursitis

ArthritisArthritis

More than 100 different types of inflammatory More than 100 different types of inflammatory or degenerative diseases that damage the jointsor degenerative diseases that damage the joints

Most widespread crippling disease in the U.S.Most widespread crippling disease in the U.S. Symptoms – pain, stiffness, and swelling of a Symptoms – pain, stiffness, and swelling of a

jointjoint Acute forms are caused by bacteria and are Acute forms are caused by bacteria and are

treated with antibioticstreated with antibiotics Chronic forms include osteoarthritis, rheumatoid Chronic forms include osteoarthritis, rheumatoid

arthritis, and gouty arthritisarthritis, and gouty arthritis

Osteoarthritis (OA)Osteoarthritis (OA)

Most common chronic arthritis; often called Most common chronic arthritis; often called “wear-and-tear” arthritis“wear-and-tear” arthritis

Affects women more than menAffects women more than men 85% of all Americans develop OA85% of all Americans develop OA More prevalent in the aged, and is probably More prevalent in the aged, and is probably

related to the normal aging processrelated to the normal aging process

Osteoarthritis: CourseOsteoarthritis: Course

OA reflects the years of abrasion and OA reflects the years of abrasion and compression causing increased production of compression causing increased production of metalloproteinase enzymes that break down metalloproteinase enzymes that break down cartilagecartilage

As one ages, cartilage is destroyed more As one ages, cartilage is destroyed more quickly than it is replacedquickly than it is replaced

The exposed bone ends thicken, enlarge, form The exposed bone ends thicken, enlarge, form bone spurs, and restrict movementbone spurs, and restrict movement

Joints most affected are the cervical and lumbar Joints most affected are the cervical and lumbar spine, fingers, knuckles, knees, and hipsspine, fingers, knuckles, knees, and hips

Osteoarthritis: TreatmentsOsteoarthritis: Treatments

OA is slow and irreversibleOA is slow and irreversible Treatments include:Treatments include:

Mild pain relievers, along with moderate activityMild pain relievers, along with moderate activity Magnetic therapy Magnetic therapy Glucosamine sulfate decreases pain and Glucosamine sulfate decreases pain and

inflammationinflammation

Rheumatoid Arthritis (RA)Rheumatoid Arthritis (RA)

Chronic, inflammatory, autoimmune disease of Chronic, inflammatory, autoimmune disease of unknown cause, with an insidious onsetunknown cause, with an insidious onset

Usually arises between the ages of 40 to 50, Usually arises between the ages of 40 to 50, but may occur at any agebut may occur at any age

Signs and symptoms include joint tenderness, Signs and symptoms include joint tenderness, anemia, osteoporosis, muscle atrophy, and anemia, osteoporosis, muscle atrophy, and cardiovascular problemscardiovascular problems The course of RA is marked with exacerbations The course of RA is marked with exacerbations

and remissionsand remissions

Rheumatoid Arthritis: CourseRheumatoid Arthritis: Course

RA begins with synovitis of the affected jointRA begins with synovitis of the affected joint Inflammatory chemicals are inappropriately Inflammatory chemicals are inappropriately

releasedreleased Inflammatory blood cells migrate to the joint, Inflammatory blood cells migrate to the joint,

causing swellingcausing swelling

Rheumatoid Arthritis: CourseRheumatoid Arthritis: Course

Inflamed synovial membrane thickens into a Inflamed synovial membrane thickens into a pannuspannus

Pannus erodes cartilage, scar tissue forms, Pannus erodes cartilage, scar tissue forms, articulating bone ends connectarticulating bone ends connect

The end result, ankylosis, produces bent, The end result, ankylosis, produces bent, deformed fingersdeformed fingers

Rheumatoid Arthritis: Rheumatoid Arthritis: TreatmentTreatment

Conservative therapy – aspirin, long-term use Conservative therapy – aspirin, long-term use of antibiotics, and physical therapyof antibiotics, and physical therapy

Progressive treatment – anti-inflammatory Progressive treatment – anti-inflammatory drugs or immunosuppressants drugs or immunosuppressants

The drug Enbrel, a biological response The drug Enbrel, a biological response modifier, neutralizes the harmful properties of modifier, neutralizes the harmful properties of inflammatory chemicalsinflammatory chemicals

Gouty ArthritisGouty Arthritis

Deposition of uric acid crystals in joints and soft Deposition of uric acid crystals in joints and soft tissues, followed by an inflammation responsetissues, followed by an inflammation response

Typically, gouty arthritis affects the joint at the Typically, gouty arthritis affects the joint at the base of the great toebase of the great toe

In untreated gouty arthritis, the bone ends fuse In untreated gouty arthritis, the bone ends fuse and immobilize the jointand immobilize the joint

Treatment – colchicine, nonsteroidal anti-Treatment – colchicine, nonsteroidal anti-inflammatory drugs, and glucocorticoidsinflammatory drugs, and glucocorticoids

Developmental Aspects of JointsDevelopmental Aspects of Joints

By embryonic week 8, synovial joints By embryonic week 8, synovial joints resemble adult jointsresemble adult joints

Few problems occur until late middle ageFew problems occur until late middle age Advancing years take their toll on joints:Advancing years take their toll on joints:

Ligaments and tendons shorten and weakenLigaments and tendons shorten and weaken Intervertebral discs become more likely to herniateIntervertebral discs become more likely to herniate Most people in their 70s have some degree of OAMost people in their 70s have some degree of OA

Developmental Aspects of JointsDevelopmental Aspects of Joints

Prudent exercise (especially swimming) that Prudent exercise (especially swimming) that coaxes joints through their full range of coaxes joints through their full range of motion is key to postponing joint problemsmotion is key to postponing joint problems