Fibrous and Cartilaginous Joints

What are the different types of fibrous joints?

In fibrous joints the bones are connected by fibrous connective tissue.They do not have a joint cavity and are immovable or only slightly movable. Following are the three types of fibrous joints:

1.Sutures

• They are present between the bones of skull (e.g. coronal suture between frontal and parietal bones and sagittal suture between the two parietal bones).
• Bones are bound together by sutural ligaments.
• In adults, sutures allow almost no movement between the bones.
• Sutural joints are present between the bones which ossify in membrane.
• They are classified according to the shape of the bony margins and are of following types:
  • Plane sutures: e.g.  median palatine suture
  • Serrate sutures: e.g. sagittal suture
  • Denticulate sutures: e.g. lambdoid suture
  • Squamous sutures: e.g. parieto-temporal suture
  • Schindylesis: e.g. between rostrum of sphenoid and ala of vomer

2.Syndesmosis

• Bones are held together by the interosseous membrane or ligament.
• Slight movement is possible.
• e. g. intermediate/middle radioulnar and inferior tibiofibular joints.

3.Gomphosis

• Cone shaped root of tooth fits into the  alveolar socket of the maxilla      or mandible bone (like a peg in the socket).
• The tooth is attached to the alveolar socket by periodontal ligament.
• The joint is immovable.

What are the different types of Cartilaginous Joints?

In cartilaginous joints the bones are united by cartilage. They are slightly movable joints and lack a joint cavity. There are two types of cartilaginous joints:

1.Primary cartilaginous joint (Synchondrosis)

• The articulating bones are connected via hyaline cartilage.
• The joints are immovable and temporary in nature i.e. after certain age the cartilaginous plate is replaced by bone (synostosis). 
• e.g. between epiphysis and diaphysis (epiphyseal plate).

2.Secondary cartilaginous joint (Symphysis)

• The articulating bones are connected via fibrocartilage.
• They are slightly movable joints.
• These are permanent joints and persist throughout life.
• They are present in the median plane.
• e.g. between two vertebral bodies (intervertebral disc), pubic symphysis and manubriosternal joint.