The Anatomy of Bone and Joint And their functions

Dr.Aashish Chaudhry, 4 mins read

The Anatomy of Bone and Joint and their functions 

All of us have bones, they make up our skeletal system and without them, we can’t function. Do you understand what bones are? 

Bone is a living tissue that forms the body's skeleton and there are 3 types of bone tissue that include the following:

• Compact tissue - This is the hard, outer tissue of bones.
• Cancellous tissue -This is a sponge-like tissue inside the bones.
• Subchondral tissue - The smooth tissue found at the ends of bones is also covered with another type of tissue called cartilage. Cartilage is a specialized, gristly connective tissue that is found in adults. It also helps develop bones in children.

The tough, thin outer layer that covers our bones is called the periosteum and there are tunnels and canals beneath this hard outer shell of the periosteum that allow blood and lymphatic vessels to carry nourishment for the bones.

Bones are categorized by their shape that is short, long, flat, or irregular. Primarily, most bones are referred to as either long or short.

Human Skeleton has 206 bones; this does not include teeth and sesamoid bones (small bones found in the cartilage). We have 

• 80 axial bones - these include the head, hyoid, ribs, facial, auditory, trunk, and sternum.
• 126 appendicular bones - these include the arms, wrists, hands, ankles, feet, shoulders, legs, hips, and feet.

What are the functions of bone?

The main function of bone is that it gives shape and support to our bodies and it also protects some of our organs. Bones in our body also serve as a place for the storage of minerals and also as a medium for the development and storage of blood cells through the bone marrow. 

Bones are made of different kinds of cells, and bone cells include the following:

• Osteoblasts - These are found within the bone, their function is to produce new bone tissue.
• Osteoclast - A large cell formed in the bone marrow, its main function is to absorb and remove unnecessary tissue.
• Osteocyte - It is within the bone; its main function is to help preserve bone as living tissue.
• Hematopoietic - It is also found in the bone marrow and its main function is to produce red blood cells, white blood cells, and platelets.  

Even fat cells can be found within the bone marrow.

Bones are complex, their structures so intrinsic, and their functions so vital from providing strength and support for the body, to serving as a site for the development and storage of blood cells. However, these very complexities of bone also cause many disorders and diseases that affect bone.

JOINTS 

When 2 bones meet, they form a joint and most joints are mobile, which allows the bones to move. Joints consist of:

• Cartilage - Its a type of tissue that covers the surface of a bone over a joint. Cartilage helps reduce the friction of movement within a joint, preventing pain and injury. 
• Synovial membrane -This tissue lines along the joint and seals it into a joint capsule. The synovial membrane secretes a sticky and clear synovial fluid around the joint to keep it lubricated.
• Ligaments - Strong, elastic bands of connective tissue surround the joint to support and limit the joint's movement and connect the bones.
• Tendons – These are other tough connective tissue on each side of a joint, they attach to muscles that control joint movement. Tendons also connect muscles to bones.
• Bursas - Fluid-filled sacs between ligaments, bones, or other nearby structures that help cushion the friction in a joint.
• Meniscus - Its a curved portion of cartilage in the knees and other joints.

Different Types of Joints and Their Functions:- 

Human Skeleton has many joints, including the joints that don’t move in adults, like the suture joints in the skull. Joints in our body that do not move in are called fixed joints. However, other joints do move a little, such as the vertebrae. These joints are called mobile joints and they help us greatly. Mobile joints include the following:

• Ball-and-socket joints - The shoulder is a ball-and-socket joint, and so is the hip joint. These joints allow us to perform backward, sideways, forward, and rotating movements.
• Hinge joints - The hinge joints can be found in our fingers, elbows, knees, and toes. These joints only allow for bending and straightening movements.
• Pivot joints - Pivot joints include the neck joints, and these allow limited rotating movements.
• Ellipsoidal joints -  Ellipsoidal joints like the wrist joint, allow all movement except pivotal movements.

Healthy bones and joints help you stay more active as you age. Although we can’t prevent injury or avoid health conditions such as arthritis, we can surely delay and diffuse them with some things that help protect bones and joints throughout life. If you’re concerned snot your bone or joint health, get in touch with us and consult some of Delhi’s best bone doctors at Aakash Healthcare, the best orthopaedic hospital in Delhi. 

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