Carpal Metacarpal (CMC) Arthroplasty: Everything You Need to Know

wrist and metacarpal joint replacement is a surgical procedure in which a trapezium (one of the wrist bones that forms part of the thumb joint) is removed and replaced with an implant. When conservative methods fail to relieve arthritis symptoms, this procedure can help manage symptoms of thumb arthritis by reducing pain and improving thumb use for grasping, pinching, and grasping.

This article will explain how to prepare for a WMP and what to expect.

What is CMC joint replacement?

Joint replacement, or joint replacement surgery, is a surgical procedure in which parts of damaged and inflamed bone are removed and replaced with metal implants to help relieve pain and improve bodily function in people with arthritis. While joint replacements are usually performed in large joints such as the hip, knee, and shoulder, joint replacements can also be performed on the thumb joint.

Thumb arthritis, also known as carpal metacarpal joint osteoarthritis, occurs at the carpal metacarpal (CMC) joint at the base of the thumb, between the metacarpal bones and the trapezium. The forces on the joint during grasping, pinching, and grasping movements and the loss of supporting ligament strength with age often cause the thumb joint to degenerate over time. Because the thumb is a very flexible joint, it lacks the stability to withstand repeated pressure and is prone to wear and tear over time.

CMC joint replacements often involve Trapeziectomy, a surgical procedure in which the trapezoid bone is removed from the wrist. After the trapezoid is removed, a tendon graft or implant made of silicone or metal is inserted into the missing space to complete the arthroplasty.

potential risks

Most people recover well after undergoing CMC joint replacement. Potential risks associated with hand and wrist surgery include:

  • Infect
  • bleeding and blood clots
  • nerve damage
  • hand scar
  • Residual or recurring symptoms
  • Complex regional pain syndrome (chronic pain)

Other risks associated with joint replacement surgery for the thumb CMC joint include:

  • Tendon Binding: Tendons used in transplant surgery to make implants can become bound, causing scarring and adhesions to the tendon.This will cause the tendon to stick to its sheath, preventing it from gliding smoothly and functioning properly
  • Sinking: When a joint implant is used, the body mounts an inflammatory response to the new foreign body, causing the implant to gradually sink into the surrounding bone

Talk to your healthcare provider about the possible risks of CMC joint replacement surgery to determine if your age, current health, and medical history are right for you.

Objectives of CMC joint replacement surgery

CMC joint replacement is often used for thumb arthritis that does not improve with conservative treatment options, including:

  • Activity adjustment: Rest and avoidance of painful activities, especially repetitive grasping, grasping, and pinching, can reduce inflammation in the thumb and promote recovery.
  • Adaptive equipment: Using special tools to help with tasks such as opening jars and using utensils can help reduce strain and inflammation of the thumb joint.
  • Medications: Anti-inflammatory and pain relievers are often prescribed to help manage symptoms.
  • Cortisone injection: A healthcare provider may inject cortisone into your thumb to locally reduce pain and inflammation.
  • Braces or splints: Thumb braces or splints can be used to externally support the thumb joint to reduce thumb strain while using both hands to complete daily activities.
  • Physical therapy or occupational therapy: Physical therapy or occupational therapy can help strengthen the hand and wrist muscles to support the carpometacarpal joint of the thumb, thereby improving the use and function of the hand. Treatment modalities can also be used to help relieve pain.

How to prepare

The surgical team will give you more detailed instructions on what you need to do in the days and hours before your surgery. It is recommended that you stay active, eat a healthy diet and quit smoking prior to any surgery to promote optimal healing and smooth recovery.

You may need to stop taking certain medications a few days before surgery to prevent excessive bleeding during surgery or interaction with anesthesia. Always consult your healthcare provider about all prescription, over-the-counter (OTC) medicines and supplements you take for safety.

CMC joint replacement is usually performed as an outpatient surgical procedure in a hospital or outpatient surgical center. You may go home the day of your surgery. You are not allowed to drive to and from the hospital before and after surgery, so arrange for a friend or family member to provide transportation for you.

12 smart tips to help you prepare for surgery and stay healthy

what to expect

On the day of your CMC joint replacement, you will be taken to a preoperative room where you will be asked to change into a gown. You will undergo a brief physical examination and answer questions from the surgical team about your medical history.

You will be taken into the operating room where you will be given anesthesia. The surgery will be performed under general anesthesia, where you are asleep during the procedure, or under local anesthesia, which involves only numbing your arm so you don’t feel anything during the procedure.

Before making the incision, the skin of your hands and thumb will be disinfected with an antiseptic solution to kill bacteria and prevent infection.

During surgery

Your surgeon will make an incision along the top of the metacarpal bone of your thumb and use a metal retractor to hold the incision open. The radial nerve and radial artery were carefully removed with a retractor to fully expose the underlying bone.

Your CMC joint replacement procedure will depend on the type of implant used to replace the trapezoid bone. Implants can be made from metal or silicone, or from tendon grafts from the wrist muscles in a process called ligament reconstruction and tendon insertion (LRTI).

For LRTI surgery, a trapezius resection is performed first to remove your trapezius bone.the tendon flexor carpi radialis Your wrist muscles will also be cut and surgically reattached to the metacarpal bone of your thumb. The partially severed tendon will be used to reconstruct the palmar oblique ligament that connects the metacarpal bone of the thumb to the trapezoid.

The rest of the tendon is then folded 8 to 10 times, stitched together like an accordion, and inserted into the space where the trapezoid is. As you heal, the tendons harden into scar tissue and provide extra stability to replace the missing bone in the carpometacarpal joint.

Silicone or metal implants

If your CMC joint replacement does not use a tendon graft, a silicone or metal implant will be used. A silicone implant can be inserted after a trapezoid resection to remove the trapezoid space and close the joint capsule tightly.

Silicone implants were initially used primarily for CMC arthroplasty, but have been associated with a risk of joint dislocation, cyst (fluid-filled sac) formation, synovitis, or inflammation and swelling of the synovium lining the CMC joint.

If a metal implant is used, the trapezoid will not be performed and the trapezoid will remain in place. Instead, metal implants are inserted into the metacarpal bones of the thumb connecting the trapezoids to form the CMC joint.This process is called saddle hemiarthroplasty.

The CMC joint capsule will be incised and a bone saw will be used to cut vertically into the metacarpal bone of the thumb. Then remove 6 to 8 mm of bone. Trapezoids can also be reshaped or contoured to improve the shape of the bone and the mobility of the articular surfaces.

A metal implant is then inserted into the space where the metacarpal bone was removed and hammered into the remaining metacarpal bone before the joint capsule is tightly sutured.

after surgery

After your CMC joint replacement, you will be taken to the recovery room and your vital signs will be monitored as the effects of the anesthesia begin to wear off. Once you are stable, you can usually go home an hour or two after surgery.


After surgery, your thumb will be placed in a cast for three to four weeks. After the cast is removed, you’ll get a plastic splint that you can wear for four to six weeks. Plastic splints should always be worn. However, it can be removed when performing specific exercises to strengthen the thumb. You will usually have your splint removed between six weeks and three months after surgery.

You will be referred to a physical or occupational therapist who will develop a plan of care and give you exercises to restore range of motion in your thumb and hand. It can take six to eight weeks to regain full thumb motion.

What you can do to control pain and swelling

Your thumb may feel sore and uncomfortable after surgery. Your healthcare provider will prescribe pain medication to help manage your symptoms. Elevating your hand will help reduce swelling, which can reduce pain, increase range of motion, and speed up recovery time.

wound care

After the cast is removed, your surgeon will give you specific instructions on how to clean around the incision site. Avoid applying lotions, creams, or ointments directly to the area unless specifically instructed by your healthcare provider.

Contact your healthcare provider right away if you have a fever or if the surgery site is red, warm, or swollen, as these are signs that you may have an infection.

coping with rehabilitation

It is important to follow all instructions from your surgeon and your physical or occupational therapist to promote optimal healing and recovery from CMC arthroplasty.

Recommendations for optimal recovery include:

  • Get enough sleep at night, at least seven to eight hours
  • Eat a healthy diet and manage a healthy weight
  • stay hydrated
  • Stay positive and learn how to deal with and manage stress
  • Exercise as prescribed by your physical or occupational therapist
  • Stay active and limit the amount of time you spend sitting each day
  • Always wear the splint as directed by your healthcare provider, except to remove the splint to clean incisions and perform exercises

lifestyle adjustments

It will take some time after surgery to regain full use of your thumb and hand. Make sure you:

  • Raise your hands when sitting or lying down to reduce pain and swelling
  • Don’t force yourself to do too much too soon – be careful when lifting, pushing and pulling
  • Attend all regularly scheduled therapy sessions and follow up on a home exercise program

Adaptive tools such as specialized scissors, bottle openers, button hooks, key turners, and pen grips are also available to help you with tasks that require fine motor and bimanual dexterity that may be difficult after surgery.


CMC joint replacement is a surgical procedure used to treat carpal metacarpal joint osteoarthritis by replacing the trapezoid bone of the thumb joint with a tendon graft or a silicone or metal implant after conservative treatment fails to relieve symptoms.

Surgery is usually done on an outpatient basis and you will go home the same day. After surgery, your thumb will be placed in a cast for 3 to 4 weeks, followed by a plastic splint for 4 to 6 weeks. Typically, it takes six to eight weeks to regain full motion of the thumb.

VigorTip words

Recovery time after CMC joint replacement varies from a few weeks to a few months. It is critical that you follow proper precautions after surgery, including limiting the use of your hands and wearing a splint. After your health care provider or physical or occupational therapist clears up your condition, you can engage in more intense activities.