Classification Schemes

The three joint classes based on function are:

synarthrosis, amphiarthrosis, and diathrosis

Synarthrosis

immovable joints

The types of synarthroses are:

sutures, gomphosis, synchondrosis, and synostosis

Amphiarthrosis

slightly movable joints; connected by collagen fibers or cartilage

Diarthrosis

freely movable joints; all are synovial joints

The four joint classes based on composition are:

bony, fibrous, cartilaginous, and synovial

sutures

interlocked bones; skull

gomphosis

ligaments that hold teeth in socket

sychondrosis

cartilaginous bridge; epiphyseal cartilages, first ribs

synostosis

fused bones; epiphyseal lines

Types of amphiarthroses include:

syndesmosis and symphysis

syndesmosis

connected by ligament; distal tibiofibular joint

symphysis

connected by a wedge of fibrocartilage; pubic bones

Joint cavity

found in diarthroses, has walls of synovial membrane, and surrounded by fibrous capsule

articular cartilages

smooth covering over bone surface; slides over film of synovial fluid; releases watery matrix when compressed

meniscus

fibrocartilage pad that subdivides the synovial joint cavity

Accessory structures of diarthroses include:

accessory ligaments and bursae

Accessory ligaments

supports and strengthens joint; intrinsic or extrinsic to capsule

bursa

pockets filled with synovial fluid; prevents friction where tendons or ligaments rub against other tissues