Fibrous Joints

Table of Contents

• What are Fibrous Joints?
• Types of Fibrous Joints
• Suture
• Gomphysis
• Syndesmosis

Joints can simply be defined as a point or the location within the body where two or more bones meet together.

Arthrology is the study of types, structure, functions, disorders and their treatments of bone joints.

Based on their mobility, joints are classified into three types:

1. Fibrous Joints (bones in the joints are connected by fibrous tissue like collagen)
2. Synovial Joints (The ends of the bone are protected by the synovial membrane and synovial fluid)
3. Cartilaginous Joints (bones in the joints are connected by cartilage)

Explore more: Joints

Let’s learn more in detail about Fibrous joints.

Fibrous joints are defined as the joints in which the bones are connected by fibrous tissue. They are called fixed or immovable joints as they do not allow any movement between the bones. They do not have a joint cavity, and the fibrous tissue which connects the bones is made up of collage fibres.

Skull is the best example of a fibrous joint. In this type of immovable joint, the bones are fused together in such a way that they are fixed to that part and frame a structure.

There are three types of fibrous joints. They are the sutures, Gomphosis and Syndesmoses. The sutures are present between the bones of the skull. Gomphosis connects teeth with the bone cavity. The Syndesmoses are present in forearms (between radius and ulna) and leg (between tibia and fibula).

Suture

The suture joints are immovable or fixed joints consisting of a thin layer of dense fibrous connective tissue, which are found between all the bones of the skull except the mandible. These joints also provide strength to the joint by attaching the irregular interlocking edges of cranial bone. Sutures are the sites of active bone growth.

Depending upon the shape of articulating surfaces and the mode of fusion of articulating bones, the sutures are further divided into:

1. Serrate sutures — Example: Joints between the parietal bones.
2. Denticulate sutures –Example: Joints between the parietal and occipital bones.
3. Squamous sutures –Example: Tempro parietal suture present between temporal and parietal bones.
4. Limbous sutures — It is a slightly modified squamous suture. Example: Modified Tempro parietal suture.
5. Plane sutures –These types of sutures are present between the horizontal plates of two palatine bones.
6. Wedge and groove sutures–Joints present vomer bone and rostrum of the sphenoid bone.

Gomphosis

It is a specialised fibrous joint, which provides an independent and firm suspension for each tooth. It fits the teeth into their sockets, which are situated in the maxilla and the mandible. The gomphosis fibrous joints are also referred to as peg and socket joints.

Also Read: Types of Teeth

Syndesmosis

It is a type of fibrous joint, where two parallel bones are united with each other by interosseous membrane or ligaments based on the gap between the bones. This type of fibrous joint is present in the forearm and leg. In the forearms, the shaft of the radius and ulna are joined strongly by an interosseous membrane. This membrane in the forearms is flexible enough to rotate the forearms.

In the legs, the shafts of the tibia and fibula are also joined strongly by an interosseous membrane. The distal tibiofibular joint is made of fibrous connective tissue and ligaments. These ligaments along with the interosseous membrane form the Syndesmosis in the leg. The interosseous membrane in the legs is firm to lock the ankle joint for weight-bearing and stability.

Also Refer: Types of Joints

This article concludes with an introduction to fibrous joints, their types, structure and functions. To know more about joints, types of joints, other related topics and important questions, keep visiting our website at BYJU’S Biology.