Synarthrosis

Sutures of the human skull, a type of synarthrosis

Synarthrosis refers to a type of joint in the human body that is characterized by its immobility. These joints are connected by fibrous tissue and are designed to provide stability and protection rather than movement. Synarthroses are primarily found in the skull, where they are known as sutures.

Types of Synarthrosis

Synarthroses can be classified into several types based on their structure and location:

• Sutures: These are found between the bones of the skull. Sutures are fibrous joints that allow for growth during childhood but become immobile as the individual reaches adulthood. The interlocking nature of sutures provides strength and protection to the brain.

• Gomphoses: This type of synarthrosis is found between the teeth and the sockets of the maxilla or mandible. The fibrous connection is known as the periodontal ligament.

• Synchondroses: These are cartilaginous joints where the bones are joined by hyaline cartilage. An example is the epiphyseal plate in growing bones, which eventually ossifies to become a synostosis.

Function

The primary function of synarthroses is to provide stability and protection. In the skull, sutures protect the brain by absorbing impact and distributing forces. The immobility of these joints is crucial for maintaining the integrity of the cranial cavity.

Development

During development, synarthroses such as sutures allow for the growth of the skull. The fibrous tissue between the bones permits expansion as the brain grows. Over time, these joints ossify and become more rigid, a process known as synostosis.

Related Pages

• Joint
• Suture (joint)
• Gomphosis
• Synchondrosis
• Synostosis