© 2014 Pearson Education, Inc. PowerPoint ® Lecture Presentations prepared by Leslie Hendon University of Alabama, Birmingham 9 Joints

© 2014 Pearson Education, Inc. I. Joints ► bones meet at joints (articulations) ► arthro = joint ► Joints can be classified by function or structure

© 2014 Pearson Education, Inc. A. Functional classification is based on amount of movement 1. Synarthroses—immovable 2. Amphiarthroses—slightly movable 3. Diarthroses—freely movable B. Structural classification is based on: ► Material that binds bones together ► Presence or absence of a joint cavity 1. Fibrous 2. Cartilaginous 3. Synovial

© 2014 Pearson Education, Inc. Summary of Joint Classes

© 2014 Pearson Education, Inc. II. Fibrous Joints A. bones are connected by fibrous connective tissue B. do not have a joint cavity C. most are immovable or slightly movable ► Sutures ► Syndesmoses ► Gomphoses

© 2014 Pearson Education, Inc. Sutures A. bones are tightly bound by a minimal amount of fibrous tissue B. occur only between the bones of the skull C. allow bone growth so the skull can expand ► Synostoses—closed sutures

© 2014 Pearson Education, Inc. Syndesmoses A. bones are connected exclusively by ligaments e.g. tibio-fibular joint—immovable synarthrosis e.g. interosseous membrane between radius and ulna ► diarthroses

© 2014 Pearson Education, Inc. Gomphoses e.g. tooth in a socket connecting ligament—the periodontal ligament

© 2014 Pearson Education, Inc. III. Cartilaginous Joints A. bones are united by cartilage B. lack a joint cavity C. two types: ► Synchondroses ► Symphyses

© 2014 Pearson Education, Inc. Synchondroses A. hyaline cartilage unites bones e.g. epiphyseal plates of long bones e.g. Joint between first rib and manubrium Synchondroses Bones united by hyaline cartilage Epiphyseal plate (temporary hyaline cartilage joint) Sternum (manubrium) Joint between first rib and sternum (immovable)

© 2014 Pearson Education, Inc. Symphyses A. fibrocartilage unites bones B. resists tension and compression C. slightly movable joints that provide strength with flexibility ► Intervertebral discs ► Pubic symphysis Symphyses Bones united by fibrocartilage Pubic symphysis Body of vertebra Fibrocartilaginous intervertebral disc (sandwiched between hyaline cartilage)

© 2014 Pearson Education, Inc. IV. Synovial Joints A. most movable type of joint B. all are diarthroses C. each contains a fluid-filled joint cavity D. ends of opposing bones are covered with hyaline cartilage ► absorbs compression

© 2014 Pearson Education, Inc. V. General Structure of Synovial Joints A. articular cartilage ► ends of opposing bones are covered with hyaline cartilage ► absorbs compression B. joint (articular) cavity ► Unique to synovial joints ► Cavity holds a small amount of synovial fluid

© 2014 Pearson Education, Inc. C. Articular capsule—joint cavity is enclosed in a two-layered capsule ► Fibrous layer—dense irregular connective tissue, which strengthens joint ► Synovial membrane—loose connective tissue - lines joint capsule and covers internal joint surfaces -functions to make synovial fluid D. Synovial fluid ► viscous fluid similar to raw egg white ► arises from capillaries in synovial membrane ► contains glycoprotein molecules secreted by fibroblasts E. Reinforcing ligaments ► extracapsular ligaments—outside the capsule ► intracapsular ligaments—internal to the capsule

© 2014 Pearson Education, Inc. Synovial membrane Fibrous layer Articular (hyaline) cartilage Joint cavity (with synovial fluid) Ligament Articular capsule A typical synovial joint

© 2014 Pearson Education, Inc. Articular capsule A typical synovial joint

© 2014 Pearson Education, Inc. VI. How Synovial Joints Function A. Are subjected to compressive forces ► Fluid is squeezed out as opposing cartilages touch ► Cartilages ride on the slippery film B. Bursa - a flattened fibrous sac lined by a synovial membrane C. Tendon sheath - an elongated bursa that wraps around a tendon ► closed bags of lubricant ► reduce friction between body elements

© 2014 Pearson Education, Inc. Subacromial bursa Tendon sheath Joint cavity containing synovial fluid Articular cartilage Synovial membrane Fibrous layer Fibrous layer of articular capsule

© 2014 Pearson Education, Inc.

VII. Synovial Joints - Movements A. Three basic types of movement 1. Gliding—one bone across the surface of another 2. Angular movement—movements change the angle between bones 3. Rotation—movement around a bone's long axis

© 2014 Pearson Education, Inc. Gliding Joints Gliding occurs between: ► carpals ► articular processes of vertebrae ► tarsals

© 2014 Pearson Education, Inc. Angular Movements A. increase or decrease angle between bones 1. flexion & extension 2. abduction & adduction 3. circumduction

© 2014 Pearson Education, Inc. Extension Flexion

© 2014 Pearson Education, Inc. Flexion Extension

© 2014 Pearson Education, Inc. Flexion Extension

© 2014 Pearson Education, Inc. Abduction Adduction Circumduction

© 2014 Pearson Education, Inc. Rotation A. involves turning movement of a bone around its long axis B. only movement allowed between atlas and axis vertebrae C. occurs at the hip and shoulder joints

© 2014 Pearson Education, Inc. Rotation Lateral rotation Medial rotation

© 2014 Pearson Education, Inc. Elevation—lifting a body part superiorly Depression—moving the elevated part inferiorly Elevation Lifting a body part superiorly Depression Moving a body part inferiorly

© 2014 Pearson Education, Inc. Protraction—non-angular movement anteriorly Retraction—non-angular movement posteriorly Protraction Moving a body part in the anterior direction Retraction Moving a body part in the posterior direction

© 2014 Pearson Education, Inc. Supination—forearm rotates laterally Pronation—forearm rotates medially Pronation (P) Rotating the forearm so the palm faces posteriorly Supination (S) Rotating the forearm so the palm faces anteriorly

© 2014 Pearson Education, Inc. Inversion—turns sole medially Eversion—turns sole laterally Inversion Turning the sole of the foot medially Eversion Turning the sole of the foot laterally

© 2014 Pearson Education, Inc. Dorsiflexion—lifting the foot so it approaches the shin Plantar flexion—depressing the foot, elevating the heel Dorsiflexion Foot so it approaches the shin Plantar flexion Elevating the heel

© 2014 Pearson Education, Inc. A. Plane joint ► intertarsal and intercarpal joints ► movements are non-axial Flat articular surfaces Metacarpals Carpals Gliding Plane joint Nonaxial movement VIII. Synovial Joints - Shape

© 2014 Pearson Education, Inc. B. Hinge joints ► Angular movement is allowed in one plane ► Elbow, ankle, and joints between phalanges

© 2014 Pearson Education, Inc. C. Pivot joints ► Proximal radio-ulnar joint

© 2014 Pearson Education, Inc. D. Condylar (or ellipsoid) joints ► Side to side—abduction–adduction ► Back and forth—flexion–extension

© 2014 Pearson Education, Inc. E. Saddle joints ► 1st carpometacarpal joint ► Allows opposition of the thumb

© 2014 Pearson Education, Inc. IX. Selected Synovial Joints A. Shoulder (glenohumeral) joint ► The most freely movable joint lacks stability ► Muscle tendons contribute to joint stability

© 2014 Pearson Education, Inc. Coracoacromial ligament Subacromial bursa Fibrous layer of articular capsule Tendon sheath Tendon of biceps Glenoid labrum Synovial cavity containing synovial fluid Articular cartilage Synovial membrane Fibrous layer of capsule Frontal section through right shoulder joint

© 2014 Pearson Education, Inc.

B. Elbow joint ► Allows flexion and extension ► Articulation of the humerus with the trochlear notch of the ulna ► Tendons of biceps and triceps brachii provide stability

© 2014 Pearson Education, Inc. Cadaver photo of medial view of right elbow Ulnar collateral ligament Radius Coronoid process of ulna Ulna Humerus Medial epicondyle Articular capsule Anular ligament

© 2014 Pearson Education, Inc. C. Wrist Joint 1. Radiocarpal joint—joint between the radius and proximal carpals ► allows for flexion, extension, adduction, abduction, and circumduction 2. Intercarpal joint—joint between the proximal and distal rows or carpals ► allows for gliding movement

© 2014 Pearson Education, Inc. Right wrist, anterior (palmar) view Radius radiocarpal Thumb Ulna I II III IV V Intercarpal

© 2014 Pearson Education, Inc. D. Hip joint ► A ball-and-socket structure ► Head of femur articulates with acetabulum ► Stability from acetabulum and capsular ligaments ► Muscle tendons contribute somewhat to stability

© 2014 Pearson Education, Inc. Photo of the interior of the hip joint, lateral view ligamentum teres Acetabular labrum Synovial membrane Head of femur Articular capsule (cut)

© 2014 Pearson Education, Inc. E. Knee joint ► Acts primarily as a hinge joint ► Two fibrocartilage menisci occur within the joint cavity ► Femoropatellar joint—shares the joint cavity

© 2014 Pearson Education, Inc. Sagittal section through the right knee joint Lateral meniscus Tendon of quadriceps femoris Suprapatellar bursa Synovial cavity Deep infrapatellar bursa Patellar ligament Posterior cruciate ligament Anterior cruciate ligament

© 2014 Pearson Education, Inc. Anterior view of right knee Lateral patellar retinaculum Fibular collateral ligament Medial patellar retinaculum Tibial collateral ligament Patellar ligament

© 2014 Pearson Education, Inc.

Osteoarthritis of the knee.

© 2014 Pearson Education, Inc. Clinical Application - Knee Injuries

© 2014 Pearson Education, Inc. F. Ankle joint ► A hinge joint between: ► Allows the movements dorsiflexion and plantar flexion only

© 2014 Pearson Education, Inc. Tibia Metatarsophalangeal joint Calcaneus Interphalangeal joint Ankle joint Talonavicular joint Cuneonavicular joint Tarsometatarsal joint Cadaver photo of ankle and foot, sagittal section