Joints

Compiled by Marc Garcia

Classification

Joints can be classified:

1. Structurally

2. by their freedom of movement

3. Synovial joints can be classified by:

• Type of motion

• Range of motion

Freedom of Movement

Joints can be:• Synarthroses

▪ immoveable

• Amphiarthroses▪ slightly moveable

• Diarthroses▪ freely moveable

Structural Classifications

Think:

What type of tissue is the jointmade of?

How are the two bones heldtogether?

Structural Classifications

Fibrous Joints• Made of fibrous connective tissue

collagen fibers• Sutures

Synarthrotic Sagittal suture Lambdoid suture Coronal suture Squamous suture Between palatine processes of the maxillae

Structural ClassificationsFibrous

Gomphoses• Tooth and Alveolar socket

Synarthrotic Held by the periodontal ligament

Structural ClassificationsFibrous

Syndesmoses• Distal tibiofibular joint

Held by interosseous ligament Amphiarthrotic

• Distal radioulnar Held by interosseous ligament Amphiarthrotic

Structural ClassificationsCartilaginous

Cartilaginous Joints are held togetherby cartilage

• Hyaline cartilage• Fibrocartilage

There are two kinds• Symphyses• Synchondroses

Structural ClassificationsCartilaginous

Symphyses• Two bones joined by fibrocartilage

▪ Intervertebral discs• Amphiarthrotic

▪ Pubic symphysis• Synarthrotic in males• Amphiarthrotic in females

Structural ClassificationsCartilaginous

Synchondroses• A joint made of hyaline cartilage

▪ Epiphyseal plate• Only in long bones• Synarthrotic

▪ Costal cartilage• Only between ribs/sternum and

clavicle/sternum• Synarthrotic

Structural ClassificationsSynovial

Synovial joints• Joined by a synovial cavity

▪ Articular cartilage covering bone ends▪ Fibrous capsule surrounding joint▪ Inner layer of capsule is the synovial

membrane• Membrane secretes synovial fluid• Membrane composed of areolar tissue

Structural ClassificationsSynovial

• Some may have a meniscus▪ Pads of fibrocartilage▪Absorb pressure and shock▪Also known as articular discs

• Some may have accessory ligaments▪Lie outside of capsule

• Some may have bursae▪Synovial-filled fluid sacs ▪Reduce friction between muscles and

between tendons/bones

Structural ClassificationsSynovial

• May be classified by▪ Range of motion▪ Type of motion

• Range of Motion▪ Monaxial▪ Biaxial▪ Multiaxial

Structural ClassificationsSynovial

• Type of motion▪ Hinge joints

• Monaxial• Interphalangeal, humeroulnar,

humero- radial, tibiofemoral, talocrural, atlantooccipital

▪ Pivot joints• One bone fits into ring-like ligament• Monaxial• Atlantoaxial, proximal radioulnar

Structural ClassificationsSynovial

• Type of motion (cont.)▪ Gliding (plane) joints

• Flat or slightly concave/convex surfaces• The only amphiarthrotic synovial joint• Monaxial• Intercarpal, intertarsal, between articular

processes of vertebrae, sternoclavicular, patellofemoral

Structural ClassificationsSynovial

• Type of motion (cont.)▪ Saddle joint

• Two surfaces, each concave in one direction, convex in the other.

• Biaxial• Trapeziometacarpal I

▪ Condyloid (ellipsoid) joints• Oval surface fits into depression in

another• Biaxial• Radiocarpal, metacarpophalangeal

Structural ClassificationsSynovial

• Type of motion (cont.)▪ Ball-and-socket joints

• Hemispherical head fits into cup• Multiaxial• Humeroscapular, Coxal

Structural ClassificationsSynovial

• Type of motion (cont.)▪ Some joints are a combination

• Temporomandibular– condyloid, hinge, and gliding

Movement of Diathroses

• Flexion▪ Decrease the angle of a joint▪ Like bending your elbow▪ Ball & Socket, Condyloid, Hinge

• Extension▪ Straightens a joint▪ Like raising your head▪ Ball & Socket, Condyloid, Hinge

Movement of Diathroses

• Hyperextension▪ Extension beyond 180 degrees▪ Like pushing palms back or▪ Like looking up at sky▪ Condyloid, Hinge, (Ball & Socket)

Movement of Diathroses

• Abduction▪ Movement away from midsagittal

line▪ Like spreading fingers or legs▪ Ball & Socket, Condyloid, (Saddle)

• Adduction▪ Returning to midsagittal line▪ Like putting arms down to sides▪ Ball & Socket, Condyloid, (Saddle)

Movement of Diathroses

• Circumduction▪ Making a circular motion▪ Like rolling your head or▪ Making circles with your arms▪ Actually a combination of Flexion,

Abduction, Extension, Adduction

▪ Ball & Socket, Condyloid

Movement of Diathroses

• Opposition▪ Moving thumb towards fingertips▪ Give us “opposable thumbs”

• Reposition▪ Returning thumb to original position

▪ Trapeziometacarpal (thumb) is the only joint capable of these (Saddle)

Movement of Diathroses

• Lateral Rotation▪ Bone turns on a longitudinal axis▪ Like twisting elbow; NOT forearm!▪ Like twisting trunk or head▪ Lateral means away from midline

• Medial Rotaion▪ Same, but medial means towards

midline▪ Ball & Socket, Pivot

Movement of Diathroses

• Supination▪ Twisting forearm so palm faces

foward▪ Refers only to forearm▪ Like holding a “bowl of soup”▪ Pivot

• Pronate▪ Twisting forearm so palm faces back▪ Pivot

Movement of Diathroses

• Elevation▪ Raising vertically▪ Like shrugging shoulders▪ Temporomandibular▪ Sternoclvicular

• Depression▪ Lowering vertically▪ Same joints as above

Movement of Diathroses

• Protraction▪ Moving forward▪ Like jutting your jaw out▪ Temporomandibular

• Retraction▪ Moving towards rear▪ Temporomandibular

Movement of Diathroses

• Lateral Excursion▪ Moving to side away from midline▪ Like when you bite the corner of

lip▪ Temporomandibular

• Medial Excursion▪ Returning sideways to midline▪ Temporomandibular

Movement of Diathroses

• Dorsiflexion▪ Pointing foot up▪ Like trying to walk on your heels▪ Talocrural (Ankle)

• Plantarflexion▪ Pointing foot down▪ Think of pointing to “plants” on

ground▪ Talocrural (Ankle)

Movement of Diathroses

• Inversion▪ Turning soles towards midline▪ Think turn “in”▪ Talocrural (Ankle)

• Eversion▪ Turning soles towards sides▪ Talocrural (Ankle)

Quiz

Joint Held together

by:

Freedom of

Movement

Number of axes

Capable of:

Pivot Synovial cavity

Diarthrosis Monaxial

RotationSupination/Pronation

Syn-chondrosis

Cartilaginous Synarthrosis

Gomphosis

Fibrous Synarthrosis

Hinge Synovial cavity

Diarthrosis Monaxial

Flexion, extension, hyperextesion

Condyloid Synovial cavity

Diarthrosis Biaxial Flexion, extension, hyperextension, abduction, adduction, circumduction

Suture Fibrous Synarthrosis

Gliding Synovial cavity

Amphi-arthrosis

Monaxial

Joint Held together

by:

Freedom of

Movement

Number of axes

Capable of:

Syn-desmosis

Fibrous Amphi-arthrosis

Ball-and-Socket

Synovial cavity

Diarthrosis Multi-axial

Flexion, extension, abduction, adduction, circumduction, lateral and medial rotation

Symphysis Cartilaginous Synarthrosis/Amphi-arthrosis

Temporo-mandibular

Synovial cavity

Diarthrosis Special Elevation, depression, protraction, retraction, lateral/medial excursion

Saddle Synovial cavity

Diarthrosis Biaxial Opposition, reposition, adduction, abduction

Ankle (Talocrural)

Synovial cavity

Diarthrosis Special Dorsiflexion, Plantarflexion, Inversion, Eversion

Joint Held together

by:

Freedom of

Movement

Number of axes

Type of

Motion

Capable of:

Atlanto-axial

Synovial cavity

Diarthrosis Monaxial

Pivot Rotation

Atlanto-occipital

Synovial cavity

Diarthrosis Monaxial

Hinge Flexion, extensionhyperextension

Costal Cartilage

Synchondrosis, cartilaginous

Synarthrosis

Coxal Synovial cavity

Diarthrosis Multi-axial

Ball & Socket

Flexion, extension, adduction, abduct. circumduction, rotation

Cranial Sutures

Sutures,Fibrous

Synarthrosis

Distal radioulnar

Syndesmoses, Fibrous

Amphi-arthrosis

Joint Held together

by:

Freedom of

Movement

Number of axes

Type of

Motion

Capable of:

Distal tibiofibular

Syndesmosus, Fibrous

Amphi-arthrosis

Epiphyseal Plate

Synchondrosis

Synarthrosis

Humero-radial

Synovial cavity

Diarthrosis Monaxial

Hinge Flexion, extension

Humero-ulnar

Synovial cavity

Diarthrosis Monaxial

Hinge Flexion, extension

Humero-scapular

Synovial cavity

Diarthrosis Multi-axial

Ball & Socket

Flexion, extensionadduction, abduccircumduction, rotation

Intercarpal/Intertarsal

Synovial cavity

Amphi-arthrosis

Monaxial

Gliding

Joint Held together

by:

Freedom of

Movement

Number of axes

Type of

Motion

Capable of:

Inter-phalangeal

Synovial cavity

Diarthrosis Monaxial

Hinge Flexion, extension

Inter-vertebral

Synchondrosis,cartilaginous

Amphi-arthrosis

Metacarpo-phalangeal

Synovial cavity

Diarthrosis Biaxial Con-dyloid

Abduction, adduction

Patello-femoral

Synovial cavity

Amphi-arthrosis

Monaxial

Gliding

Proximal radioulnar

Synovial cavity

Diarthrosis Monaxial

Pivot Rotation, pronation, supination

Pubic Symphysis

Symphysis, cartilaginous

Synarthrosis/amphi-

Joint Held together

by:

Freedom of

Movement

Number of axes

Type of

Motion

Capable of:

Radio-carpal

Synovial cavity

Diarthrosis Biaxial Con-dyloid

Flexion, extension hyperextension, abduction, adduc

Sterno-clavicular

Synovial cavity

Amphi-arthrosis

Monaxial

Gliding

Elevation, depression, protraction, retraction

Talocrural Synovial cavity

Diarthrosis Biaxial Hinge Dorsiflexion, Plantar Flexion, Inversion, Eversion

Temporo-mandibular

Synovial cavity

Diarthrosis Multi-axial

Con-dyloid, hinge, gliding

Elevation, depres-sion,protraction, retraction, lateral and medial excursion

Joint Held together

by:

Freedom of

Movement

Number of axes

Type of

Motion

Capable of:

Tibio-femoral

Synovial cavity

Diarthrosis Monaxial

Hinge Flexion, extension, slight rotation

Tooth/ Alveolar Socket

Gomphosis, Fibrous

Synarthrosis

Trapezio-metacarpal

Synovial cavity

Diarthrosis Biaxial Saddle Opposition, Reposition

Articular processes of vertebrae

Symphysis, Cartilaginous

Amphi-arthrosis