Joints & Classification

Fibrous, cartilaginous, & synovial joints. Movement of synovial joints. Anatomy of the knee joint.

Sutures

A fibrous joint composed of a thin layer of dense fibrous connective tissue that unites the skull bones

Interosseous ligament

• A type of fibrous tissue, specifically classified as a syndesmosis

• Made of a broad sheet of ligament that allows some movement between adj. bones 

• Ex. the distal tibiofibular joint 

Interosseous membrane

• A type of fibrous joint, specifically classified as a syndesmosis

• A substantial sheet of fibrous connective tissue that binds neighboring long bones

→ permits slight movement

• Allows more surface area for the attachment of muscles

• Ex. Between the radius & ulna + between the tibia & fibula

Gomphosis

• A type of fibrous joint, specifically classified as a syndesmosis

→ AKA the dentoalveolar joint 

• A cone-shaped peg fits into a socket

→ permits no movement 

• Ex. the root of a tooth in its dental socket 

Fibrous joint

Lack a synovial cavity, have the articulating bones held together by fibrous connective tissue, and permit little or no movement

Cartilaginous joint

• Lacks synovial cavity

• Articulating bones are either connected by fibrous connective tissue or hyaline cartilage

→ 2 types: synchondrosis & symphysis

Synovial joint 

• Have a synovial cavity

• Freely movable (diarthrotic)

• Articulating bones are covered in articular cartilage (hyaline)

→ articular cartilage reduces friction at the joint w/ movement & helps to absorb shock

• An articular capsule surrounds this joint, uniting the articulating

→ outer fibrous layer

→ inner joint membrane that secretes a lubricating membrane

Synarthrosis joint

An immoveable joint

Amphiarthrosis joint

A slightly moveable joint

Diarthrosis joint 

A freely moveable joint

Synchondrosis

• A type of cartilaginous joint

• Connecting material is hyaline cartilage, allowing no movement

• Ex. An epiphyseal plate has hyaline cartilage localized in growth centers during endochondral bone formation

Symphysis

• A type of cartilaginous joint 

• Connecting material is a disc of fibrocartilage, allowing some movement

• Ex. intervertebral discs, pubic symphysis