The elbow is made up of three bones that join together to form a complex hinge consisting of three separate joints. The upper arm bone, or humerus, connects to the forearm bones, the radius and the ulna, forming the radiohumeral and ulnohumeral joints. The radius and ulna, in turn, form a joint of their own called the radioulnar joint. The entire elbow joint is surrounded by a strong, water tight sac called the joint capsule. This surrounding capsule contains lubricating fluid called synovial fluid. Motion at the elbow includes flexion and extension, rotation of the forearm, and rotatory movement.
Our elbow is held in place and supported by various soft tissues.
Shiny and smooth, cartilage allows smooth movement where two bones come in contact with each other. With the normal wear and tear of age, or with trauma, the cartilage can thin or become damaged causing arthritis.
Tendons are soft tissue that connects muscles to bones.
Ligaments are strong rope like tissue that connects bones to other bones. Ligaments around the elbow join to form a watertight sac called a joint capsule. This capsule surrounds the elbow joint and contains lubricating fluid called synovial fluid.
There are four main ligaments in the elbow.
Muscles are fibrous tissue capable of contracting to cause body movement.
Nerves are responsible for carrying signals back and forth from the brain to muscles in our body, enabling movement and sensation such as touch, pain, and temperature.
The three main nerves of the arm are:
The main blood vessel of the arm is the brachial artery. This artery travels across the elbow and then splits into two branches below the elbow.
These branches are:
Radial Artery: The radial artery is the largest artery supplying the hand and wrist area. Traveling across the front of the wrist, nearest the thumb, it is this artery that is palpated when a pulse is counted at the wrist.
Ulnar Artery: The ulnar artery travels next to the ulnar nerve through Guyon’s canal in the wrist. It supplies blood flow to the front of the hand, fingers and thumb.
Bursae are small fluid filled sacs that decrease friction between tendons and bone or skin. Bursae contain special cells called synovial cells that secrete a lubricating fluid. When this fluid becomes inflamed or infected, a common painful condition known as Bursitis can develop.