Total shoulder replacement surgery alleviates pain by replacing the damaged bone and cartilage with a metal and plastic implant. The shoulder joint is a ball-and-socket joint, much like the hip joint. The ball is the top of the arm bone (the humerus), and the socket is within the shoulder blade (scapula). This joint allows people an enormous range of motion at the shoulder.
When shoulder replacement surgery is performed, the ball is removed from the top of the humerus and replaced with a metal implant. This is shaped like a half-moon and attached to a stem inserted down the center of the arm bone. The socket portion of the joint is shaved clean and replaced with a plastic socket that is cemented into the scapula
A complete history and physical examination: this allows the physician to determine any correlation between symptoms of pain with past history and demands that have been placed upon the shoulder. The physician will also inquire about experiencing episodes of instability. The examination should focus on the assessment of swelling, range of motion, ligament stability, and shoulder alignment.
Getting to the Joint
The patient is first taken into the operating room and positioned on a special operating table as though lounging in a beach chair. The arm is placed on a board that will allow the surgeon to move it up or down as necessary during the surgery. Anesthesia is given and, when it has taken effect, the skin around the shoulder and upper arm is thoroughly scrubbed and sterilized with an antiseptic liquid.
An incision about six inches long is then made over the shoulder joint. The incision is gradually made deeper through muscle and other tissue until the bones of the shoulder joint are exposed.
Shoulder Joint Exposed
Replacing the Socket Portion of the Joint
The implant that replaces the socket consists of a durable plastic insert with a very smooth, cupped surface.
Removing the Surface of the Socket
The arm is maneuvered until the humeral head is dislocated from the socket.
Special precision instruments are then used to remove the damaged cartilage and bone surface from the glenoid, and to shape the socket so it will match the shape of the implant that will be inserted. Holes are then drilled into the socket to accommodate the fixation pegs on the implant. These pegs help stabilize the implant.
Inserting the Implant
The socket implant is attached by using a special kind of cement for bones. The cement is pressed into the holes. The implant is then inserted.
Replacing the Ball Portion of the Joint
The implant that replaces the ball consists of a long metal stem that fits down into the humerus. A metal head in the shape of a partial sphere is mounted on top of this stem. This head contacts the socket implant in the shoulder blade.
Metal implant to replace ball portion of shoulder joint
Preparing the Humeral Canal
The upper arm bone has relatively soft, porous bone tissue in the center. This part of the bone is called the “canal.”
Special instruments are used to clear some of this soft bone from the canal.
Using a precision guide and saw, the damaged rounded portion (ball) of the humerus is removed.
Humeral Head (Ball) is Removed
Inserting the Implant
The metal stem implant may be held in place by either using the special bone cement, or by making it fit very tightly in the canal. The surgeon will choose the best method, depending on the patient’s age and expected activity level.
If cement is used, it is injected into the canal first, and then the implant is inserted into the canal. If cement is not used, the implant is simply inserted into the canal.
On some implants, the stem and partial sphere are one piece. On others, they may be two separate pieces. If the partial sphere is a separate piece, it is usually secured to the top of the stem after the stem has been inserted.
Closing the Wound
When all the implants are in place, the surgeon places the new ball that is now part of the upper arm bone into the new socket that is part of the shoulder blade. If necessary, the surgeon may adjust the ligaments that surround the shoulder to achieve the best possible shoulder function.
When the ligaments are properly adjusted, the surgeon sews the layers of tissue back into their proper position. A plastic tube may be inserted into the wound to allow liquids to drain from the site during the first few hours after surgery. After the tube is inserted, the edges of the skin are sewn together, and a sterile bandage is applied to the shoulder. Then, the patient is taken to the recovery room.
PHYSIOLINE’S SPECIALISED PHYSIOTHERAPY HAS VITAL ROLE TO PLAY
At Physioline, all the members of the rehabilitation team work together so as to provide proper care and the therapy in order to:
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