Shoulder Joint Replacement

ExitCare ImageShoulder replacement surgery replaces damaged surfaces with artificial parts (prostheses). Usually, there are two parts used to replace this joint:

  • The humeral component replaces the head of the upper arm bone. It is made of metal (usually cobalt-chromium-based alloys). This is a rounded ball attached to a stem that fits into the humerus bone. This part comes in various sizes and can be a single piece or a modular unit.

  • The glenoid component replaces the socket (glenoid depression). It is made of ultra high-density polyethylene. Some versions have a metal tray, but totally plastic versions are more common.

Depending on the damage to your shoulder, the surgeon may replace just the humeral head (hemiarthroplasty) or both the humeral head and the glenoid (total sho ulder replacement). The shoulder parts come in various sizes and shapes to fit different people. They are held in place with either bone cement (cemented) or bone ingrowth (cementless).

The surrounding muscles and tendons hold the prosthetic parts in place, the same as the original shoulder. Each case is individual, and your surgeon will evaluate your situation carefully before making any decisions. Ask what type of implant will be used and why that choice is appropriate for you.

LET YOUR HEALTH CARE PROVIDER KNOW ABOUT:

  • Any allergies you have.

  • All medicines you are taking, including vitamins, herbs, eye drops, creams, and over-the-counter medicines.

  • Previous problems you or members of your family have had with the use of anesthetics.

  • Any blood disorders you have.

  • Previous surgeries you have had.

  • Medical conditions you have.

RISKS AND COMPLICATIONS

Generally, shoulder joint replacement is a safe procedure. However, as with any procedure, complications can occur. Possible complications include:

  • Infection.

  • Upper arm bone fracture that occurs during surgery (intraoperative fracture) or postoperative fractures.

  • Postoperative instability.

  • Loosening of the glenoid component over time.

BEFORE THE PROCEDURE

  • Do not eat or drink after midnight the day before your procedure, or as instructed.  

  • Ask your health care provider about changing or stopping any regular medicines. You may need to stop taking certain medicines up to 1 week before the procedure.  

  • You may have lab tests the morning of surgery.  

  • Make arrangements for someone to assist you at home for the first week after discharge from the hospital.

PROCEDURE

  • You will be given a medicine that numbs the shoulder area (regional anesthetic) or a medicine that makes you go to sleep (general anesthetic).

  • The surgical cut (incision) is 4–6 inches (10–15 cm) and is made on the front of the shoulder from the collarbone (clavicle) to the point where the shoulder muscle (deltoid) attaches to the upper arm bone. The surgeon will take care not to injure the nerves or blood vessels that cross the shoulder.

  • The upper arm bone is dislocated from the socket to expose the ball-like end of the upper arm. Only the portion of the bone covered by cartilage is removed. Articular cartilage covers the ends of bones where they meet the ends of other bones.

  • The center cavity of the humerus bone is cleaned and enlarged with reamers to create a hollow area that matches the shape of the implant stem. The top end of the bone is smoothed so the stem can be inserted flush with the bone surface.

  • If the ball of the prosthesis is a separate piece, the proper size is selected and attached.

  • If the socket portion of the joint is basically healthy and the surrounding muscles are intact, the surgeon may decide not to replace it. However, if the socket is arthritic, the upper arm bone is moved to the back, and the surgeon will implant the glenoid component. The surgeon prepares the socket surface by removing the remaining damaged cartilage. The socket bone is then gently reamed to match the implant. Protrusions on the artificial socket part are then fitted into holes drilled in the bone surface. Once the part fits, it is cemented into position.

  • The arm bone, with its new artificial head, is replaced in the socket. The surgeon reattaches the supporting tendons and closes the incision.

  • The arm is placed in a sling, and a support pillow is placed under the elbow to protect the repair.

  • Tubes are placed to remove excess drainage. These are usually removed a day or two later.

AFTER THE PROCEDURE

  • You will be taken to a recovery area and monitored until the anesthetic wears off.

  • Your arm will be numb from the regional anesthetic. This may last until the following day.

  • Pain medicines will be given to control the pain.

  • Typically, you will remain in the hospital for 2–3 days.

  • Your arm and shoulder will be stiff and bruised. This will improve over time.

  • An icing device is placed around your shoulder. This helps to control pain and swelling.

  • Your arm will be in a sling. You will need to wear this for 4–6 weeks after surgery.

  • The day after surgery, your health care team will begin to show you exercises for your shoulder.