JOINTS AND THE SKELETON JOINTS AND THE SKELETONJOINTS AND THE SKELETONJOINTS AND THE SKELETON

THE HUMAN SKELETON IS MULTI-FUNCTIONAL Gives structure to the body Provides for red and white blood cell development Allows for movement in a variety of directions, depending on the type of joint Protects internal organs

Terminology b Articulation (joint): b Articulation (joint): the point at which two bones meet or at which bone and cartilage meet b b Arthrology: study of joints b b Kinesiology: study of movement b b Rheumatology: medical field devoted to studying joint diseases and conditions

More Terminology b Arthroscopy: procedure that involves the examination of the interior of a joint using an arthroscope (lighted instrument the size of a pencil)

Disorders b Dislocation: displacement of articulating bones from their normal position b Rheumatism: painful state of a body structure (joint, muscle, tendon, etc.) b Arthritis: form of rheumatism which causes joint inflammation b Sprain: wrenching or twisting of a joint that may tear ligaments b Strain: stretched or partially torn muscle

Stating the obvious… b Looser joints More movable/flexibleMore movable/flexible –More vulnerable to injury b Tighter joints Less movable/flexibleLess movable/flexible –Less vulnerable to injury

Joint Classifications b Structural Classification There are 3There are 3 Based on the presence or absence of a synovial cavityBased on the presence or absence of a synovial cavity Based on which type of connective tissue is presentBased on which type of connective tissue is present b Functional Classification There are 3 Based on degree of movement

Structural Classes of joints 1. Fibrous 1. No cavity 2 Fibrous connective tissue Ex: suture 2. Cartilaginous 1. No cavity 2. Cartilage connective tissue Ex: epiphyseal plate 3. Synovial 1. Cavity present 2. Ligament connective tissue Ex: shoulder, hip, etc.

Functional Classifications 1. Synarthrosis: immovable joint 2. Amphiarthrosis: slightly movable joint 3. Diarthrosis: freely movable joint

Fibrous joints (synarthrotic) b Sutures Irregular, interlocking edgesIrregular, interlocking edges ImmovableImmovable Ex: skull sutures b Syndemoses b Gomphoses

Cartilaginous joints (amphiarthrotic) b Synchondroses b Symphysis Articulating bones are covered with hyaline cartilageArticulating bones are covered with hyaline cartilage Ex: pubis symphysis; intervertebral joints

Synovial joints (diarthrotic) b Contain ligaments b Contain menisci: pads of cartilage between bones b Contain bursae: fluid-filled pouches that reduce joint friction Inflammation = bursitisInflammation = bursitis

Types of diarthrotic/synovial joints b Planar b Hinge b Pivot b Condyloid b Saddle b Ball and socket

Planar joint b flat or slightly curved b Ex: intercarpal, sternoclavicular

Hinge joint b one convex & one concave b Ex: elbow, knee, ankle, wrist

Pivot joint b rounded bone covered by a ring-shaped bone b Ex: atlas & axis, radius-ulna

Condyloid joint b one convex, oval-shaped and one concave oval-shape b Ex: wrists, jaw

Saddle joint b saddle shape b Ex: thumb

Ball and socket joint ball-like surface that fits into a cup-like surface ball-like surface that fits into a cup-like surface Ex: shoulder, hip

Diarthrotic/Synovial joint movement types b Flexion: decrease in an angle at a joint All joints except planarAll joints except planar b Extension: increase in an angle at a joint All joints except planarAll joints except planar b Hyperextension: extension beyond anatomical position b Abduction: movement away from midline of body Condyloid, saddle, ball & socketCondyloid, saddle, ball & socket b Adduction: movement toward the midline of the body Condyloid, saddle, ball & socketCondyloid, saddle, ball & socket b Rotation: bone revolving around its own longitudinal axis b Pivot, ball & socket b Circumduction: movement in a circular path b Inversion: the plantar surface facing medially b Eversion: the plantar surface facing laterally

Types of movement

Other special movements b Elevation: upward movement Ex: closing the mouth; raising shouldersEx: closing the mouth; raising shoulders b Depression: downward movement Ex: opening the mouth; lowering shouldersEx: opening the mouth; lowering shoulders b Dorsiflexion: bending the foot dorsally Ex: stand on heelsEx: stand on heels b Plantar flexion: bending the foot toward the plantar surface Ex: point the toeEx: point the toe b Supination: palms turned forward or upward b Pronation: palms turned backward or downward b Protraction: movement forward b Retraction: movement backward

Special Movements

NAME THE JOINT NAME THE JOINT On the following slides: name the type of joint decide what kind of motion occurs there

NAME THE JOINT NAME THE JOINT Hinge joint Allows movement back and forth in one plane.

NAME THE JOINT Ball and socket joint Allows for most range of movement.

NAME THE JOINT Pivot joint Rotation of the head on the spine

NAME THE JOINT Planar joints Bones slide over one another.

NAME THE JOINT Suture No movement

NAME THE JOINT Hinge joint Allows movement back and forth in one plane.

Fractures b A CRACK OR BREAK OF A BONE

TYPES OF FRACTURES (P. 136) b SIMPLE: COMPLETE BREAK WITH NO DAMAGE TO SKIN b COMPOUND: BREAK IN BONE THAT RUPTURES THROUGH SKIN b GREENSTICK: CRACK IN A BONE b TRANSVERSE: BREAK IS AT RIGHT ANGLE b OBLIQUE: BREAK IS AT AN ANGLE

FRACTURE (continued) b COMMINUTED: BONE SPLINTERED OR CRUSHED AND BONE FRAGMENTS ARE PRESENT b FISSURE: INCOMPLETE LONGITUDINAL BREAK b SPIRAL: SEVERE TWISTING OF A BONE CAUSES BREAK COMMON IN SKIING & SKATING ACCIDENTCOMMON IN SKIING & SKATING ACCIDENT Fracture Video

Interactive Table b Table 1 Table 1 Table 1 b Table 2 Table 2 Table 2