The shoulder is made up of three bones: your upper arm bone (humerus), your shoulder blade (scapula), and your collarbone (clavicle). The shoulder is a ball-and-socket joint: The ball, or head, of upper arm bone fits into a shallow socket in your shoulder blade. This socket is called the glenoid.
The surfaces of the bones where they touch are covered with articular cartilage, a smooth substance that protects the bones and enables them to move easily. A thin, smooth tissue called synovial membrane covers all remaining surfaces inside the shoulder joint. In a healthy shoulder, this membrane makes a small amount of fluid that lubricates the cartilage and eliminates almost any friction in your shoulder.
The muscles and tendons that surround the shoulder provide stability and support. All of these structures allow the shoulder to rotate through a greater range of motion than any other joint in the body.
In shoulder replacement surgery, the damaged parts of the shoulder are removed and replaced with artificial components, called a prosthesis. The treatment options are either replacement of just the head of the humerus bone (ball), or replacement of both the ball and the socket (glenoid). There are many conditions that cause shoulder pain and disability and because of this patient think about shoulder replacement surgery.
Following is the detailed description of different conditions:
Osteoarthritis (Degenerative Joint Disease)
It is an age-related "wear and tear" type of arthritis which occurs in people 50 years of age and older. It may also occur in younger people, too. The cartilage that cushions the bones of the shoulder softens and wears away. The bones then rub against one another.
Unfortunately, there is no way to prevent the development of osteoarthritis. It is a common reason people have shoulder replacement surgery.
It is a disease in which the synovial membrane becomes inflamed and thickened. This chronic inflammation can damage the cartilage and eventually cause cartilage loss, pain, and stiffness. Rheumatoid arthritis is the most common form of a group of disorders termed "inflammatory arthritis."
This can follow a serious shoulder injury. Fractures of the bones that make up the shoulder or tears of the shoulder tendons or ligaments may damage the articular cartilage over time. This causes shoulder pain and limits shoulder function.
Rotator Cuff Tear Arthropathy
A patient with a very large, long-standing rotator cuff tear may develop cuff tear arthropathy. In this condition, the changes in the shoulder joint due to the rotator cuff tear may lead to arthritis and destruction of the joint cartilage.
Avascular Necrosis (Osteonecrosis)
Avascular necrosis is a painful condition that occurs when the blood supply to the bone is disrupted.osteonecrosis can ultimately cause destruction of the shoulder joint and lead to arthritis.Deep sea diving, severe fracture of the shoulder and heavy alcohol use are risk factors for avascular necrosis.
Itr is another common reason people have shoulder replacements. When the head of the upper arm bone is shattered, it may be very difficult for a doctor to put the pieces of bone back in place. In this case, a surgeon may recommend a shoulder replacement. Older patients with osteoporosis are most at risk for severe shoulder fractures.
Failed Previous Shoulder Replacement Surgery
It is very uncommon reason for surgery.Although uncommon, some shoulder replacements fail because of implant loosening, wear, infection, and dislocation. When this occurs, a second joint replacement surgery called a revision surgery may be necessary.
An evaluation with an orthopaedic surgeon consists of several components:
A medical history. Your orthopaedic surgeon will gather information about patient general health. A physical examination. This will assess shoulder motion, stability, and strength. X-rays. X-ray help to determine the extent of damage in shoulder. X-ray can show loss of the normal joint space between bones, flattening or irregularity in the shape of the bone, bone spurs, and loose pieces of cartilage or bone that may be floating inside the joint. Other tests. Occasionally blood tests, a magnetic resonance imaging (MRI) scan, or a bone scan may be needed to determine the condition of the bone and soft tissues of your shoulder. After that orthopaedic surgeon will review the results of evaluation and discuss whether shoulder joint replacement is the best method to relieve patient pain and improve your function.
Shoulder Replacement Options
Shoulder replacement surgery is a highly technical job . It should be performed by a surgical team with experience in this procedure. There are different types of shoulder replacements. surgeon will evaluate situation carefully before making any decisions that which which type of shoulder replacement suregry is required.
Total Shoulder Replacement
It involves replacing the arthritic joint surfaces with a highly polished metal ball attached to a stem, and a plastic socket. A total shoulder joint replacement. These components come in various sizes.it depends on shouder condition that which one to use. Implantation of a glenoid component is not advised if:
• The glenoid has good cartilage
• The glenoid bone is severely deficient
• The rotator cuff tendons are irreparably torn
Patients with bone-on-bone osteoarthritis and intact rotator cuff tendons are the candidates for total shoulder replacement. These x-rays were taken before and after total shoulder replacement surgery for osteoarthritis.