Wrist Replacement

Definition
Purpose
Description
Diagnosis/Preparation
Aftercare
Risks
Normal results
Alternatives

Definition

Wrist replacement surgery is performed to replace a wrist injured or damaged beyond repair. An artificial wrist joint replacement is implanted.

Purpose

Traumatic injuries or severe degenerative diseases affecting the wrist (such as osteoarthritis and rheumatoid arthritis with bony destruction) may require replacement of the painful wrist joint with an artificial wrist joint. The purpose of wrist replacement surgery is to restore wrist motion for activities of daily living and non-contact sports. A wrist replacement recovers lost strength by restoring length to the muscles and tendons of the fingers and wrist, and maintains a useful arc of motion and provides the stability required for an active life.

Description

Surgery to replace a wrist starts with an incision through the skin on the back of the wrist. The surgeon then moves the tendons extending over the back of the wrist out of the way to access the joint capsule on the back of the wrist joint, which is then opened to expose the wrist joint area. A portion of the carpal bones and the end of the radius and ulna are then removed from the wrist to allow room for the new artificial wrist joint. The bones of the hand and the radius bone of the forearm are prepared with the use of special instruments to form holes in the bones; the stems of the artificial joint components can then fit in. Next, the components are inserted into the holes. After obtaining a proper fit, the surgeon verifies the range of motion of the joint to ensure that it moves correctly. Finally, the surgeon cements the two sides of the joint and replaces the tendons back into their proper position before closing the wound.

A total wrist replacement implant consists of the following components:

• An ellipsoid head that simulates the curvature of the natural wrist joint and allows for a functional range of motion. This ensures that the patient may flex and extend the wrist and move it side-to-side.

KEY TERMS

Arthritis— An inflammatory condition that affects joints.

Carpal bones— Eight wrist bones arranged in two rows that articulate proximally with the radius and indirectly with the ulna, and distally with the five metacarpal bones.

Metacarpal bones— Five cylindrical bones extending from the wrist to the fingers.

Osteoarthritis— Non-inflammatory degenerative joint disease occurring mostly in older persons accompanied by pain and stiffness, especially after prolonged activity.

Radius— One of the two forearm bones. The largest portion of the radius is at the wrist joint where it articulates with the carpal bones of the hand. Above, the radius articulates with the humerus at the elbow joint.

Rheumatoid arthritis— Chronic inflammatory disease in which there is destruction of joints.

Tendon— A fibrous, strong, connective tissue that connects muscle to bone.

Ulna— One of the two bones of the forearm. The largest section articulates with the humerus at the elbow joint and the smallest portion of the ulna articulates with the carpal bones in the wrist.

• An offset radial stem that anchors the implant in the forearm. The special shape of this component is designed to assist the function of the tendons used to extend the wrist and to ensure the stability of the implant.
• An elongated radial tray surface with a molded bearing usually made of polyethylene. This component is required to distribute forces over the entire surface of the artificial joint.
• A fixation stem that is secured to the patient’s bone to add stability and eliminate rotation of the artificial joint within the bone.
• A curved metacarpal stem that secures the artificial wrist within the hand.

Diagnosis/Preparation

The orthopedic surgeon who will perform the surgery will usually require a complete physical examination of the patient by the primary care physician to ensure that the patient will be in the best possible condition to undergo the surgery. The patient

WHO PERFORMS THE PROCEDURE AND WHERE IS IT PERFORMED?

Wrist replacement surgery is performed by an orthopedic surgeon in an orthopedic hospital or in a specialized clinic.

may also need to see the physical therapist responsible for managing rehabilitation after wrist replacement. The therapist prepares the patient before surgery to ensure readiness for rehabilitation post-surgery. The purpose of the preoperative examination is also for the physician to prerecord a baseline of information that will include measurements of the patient’s current pain levels, functional wrist capacity, and the range of motion and strength of each hand.

Before surgery, patients are advised to take all of their normal medications, with the exception of blood thinners such as aspirin, ibuprofen, and other anti-inflammatory drugs that may cause greater blood loss during surgery. Patients may eat as they please the night before surgery, including solid food, until midnight. After midnight, patients should not eat or drink anything unless told otherwise by their doctor.

Aftercare

Following surgery, the patient’s wrist, hand, and lower arm are placed into a bulky bandage and a splint. A small plastic tube may be inserted to drain any blood that gathers under the incision to prevent excessive swelling (hematoma). The tube is usually removed within 24 hours. Sutures may be removed 10-14 days after surgery.

Risks

Some of the most common risks associated with wrist replacement surgery are:

• Infection. Infection can be a very serious complication following wrist replacement surgery. Infection following wrist replacement occurs in approximately 1–2% of cases. Some infections may appear before the patient leaves the hospital, while others may not become apparent for months, or even years, after surgery.
• Loosening. There is also a risk that the artificial joints may eventually fail, due to a loosening process where the metal or cement meets the bone. There

QUESTIONS TO ASK THE DOCTOR

• Will the surgery restore my wrist flexibility?
• How long will rehabilitation require?
• What are the chances of infection?
• Is alternative treatment available?
• How much wrist replacement surgery do you perform each year?
• What appearance will my wrist have after surgery?

• have been great advances in extending how long an artificial joint will last, but most will eventually loosen and require revision surgery. The risk of loosening is much greater in younger, more active people. A loose artificial wrist is a problem because of the resulting pain. Once the pain becomes unbearable, another operation is usually required to either revise the wrist replacement or perform a wrist fusion.
• Nerve injury. All of the nerves and blood vessels that go to the hand travel across the wrist joint. Wrist replacement surgery is performed very close to these structures, introducing a risk of injury either to the nerves or the blood vessels.

Normal results

Wrist replacement surgery often succeeds at restoring wrist function. On average, a wrist replacement is expected to last for 10–15 years.

Alternatives

An alternative to wrist replacement is wrist fusion (arthrodesis). Wrist fusion surgery eliminates pain by allowing the bones that make up the joint to grow together, or fuse, into one solid bone. The surgery reduces pain, but also reduces the patient’s ability to move the wrist. Wrist fusions were very common before the invention of artificial joints, and they are still performed often.

Resources

BOOKS

Browner, B. D., et al. Skeletal Trauma: Basic Science, Management, and Reconstruction, 3rd ed. Philadelphia: Elsevier, 2003.

Canale, S. T., ed. Campbell’s Operative Orthopaedics, 10th ed. St. Louis: Mosby, 2003.

DeLee, J. C., and D. Drez. DeLee and Drez’s Orthopae-die Sports Medicine, 2nd ed. Philadelphia: Saunders, 2005.

ORGANIZATIONS

The American Academy of Orthopaedic Surgeons (AAOS).6300 North River Road, Rosemont, Illinois 60018-4262. (847) 823-7186; (800) 346-AAOS. http://www.aaos.org (accessed April 18, 2008).

OTHER

“Wrist Replacement.” University of Maryland Information Page. http://www.wristreplacement.com/ (accessed April 18, 2008).

“Wrist Joint Replacement (Arthroplasty).” AAOS. http://orthoinfo.aaos.org/topic.cfm?topic=A00019 (accessed April 18, 2008).

Monique Laberge, PhD