Pyrocarbon interposition arthroplasty Info Consent
Reviewed by Dr Kieran Hirpara, Specialist Orthopaedic Surgeon Last reviewed
Why this operation has been suggested
This page reflects how Dr Kieran Hirpara, an upper-limb surgeon at Mater Private Hospital Rockhampton, approaches this in our clinic. We usually recommend this surgery after non-operative care has not given enough improvement. You likely reached us via a GP or physiotherapist referral. We assess your history and imaging to confirm the diagnosis.
This procedure involves placing a spacer in the base of your thumb. It is typically offered for early wear-and-tear arthritis that has not responded to rest, splinting, or therapy. It is also considered when removing the bone entirely feels too destructive, or when a full joint replacement seems too extensive. The main benefit is pain relief and improved movement. Studies show good implant longevity with a minimum 8-year follow-up. We aim to preserve your thumb length and key pinch strength while stabilising the joint.
Before the operation
Please fast for six hours before your surgery. Stop blood thinners only after your surgeon advises. Arrange a lift home and bring a list of your current medications. Wear comfortable, loose clothing. You may need an X-ray to check your joint, blood tests to ensure you are fit for anaesthesia, and an anaesthetic review to discuss pain control. We perform this as an open procedure using a single incision over the thumb base. This allows direct access to the joint. Please follow all specific instructions given by our team regarding preparation. These steps help ensure your surgery proceeds safely and smoothly.
On the day
You arrive at the hospital and check in with our nursing team. Your surgeon reviews your details before you meet the anaesthetist. This operation is done under general anaesthetic. You will be fully asleep for the operation. Some patients may also have a regional nerve block for post-operative pain relief — the anaesthetist decides on the day based on your individual circumstances.
You are then moved to the operating theatre. We perform the procedure using an open approach with a single conventional incision over the operative site. This allows direct access to the joint without complex scopes or additional tools. Once the surgery is complete, you are taken to the recovery area. Our team monitors you closely as you wake up. You will rest here until you are stable and ready to go home with your caregiver.
What the operation involves
Your surgeon makes a single cut over the base of your thumb. Through this opening, they carefully remove part of the trapezium bone. This small bone sits at the base of your thumb and is where the arthritis is causing you pain. By removing this worn section, we create space for the implant.
We then place a pyrocarbon spacer into this space. This soft, flexible implant acts like a cushion between your thumb bones. It helps to keep your thumb joint stable while allowing it to move more freely. This approach is designed to preserve the natural length of your thumb and maintain your key pinch strength.
Once the spacer is in place, your surgeon closes the cut with stitches. A dressing is applied to protect the area as it begins to heal. This procedure offers a middle ground for patients with early wear-and-tear arthritis who have not found relief with non-surgical treatments. It avoids removing the entire bone, which some patients find too drastic, while providing more movement than simpler procedures.
After the operation
You will wake up in the recovery ward with your hand in a soft dressing and a sling. We manage pain with standard medications to keep you comfortable. Most patients stay one night in hospital after this operation, though some are able to go home the same day. Please ensure someone stays with you for the first 24 hours to help you rest. Your thumb will be supported in a splint for four to six weeks. You must not drive while wearing this splint, as it prevents a safe grip on the wheel. You can return to driving once the splint is removed and your surgeon clears you. For more details, see Driving after upper-limb surgery.
Recovery
You can expect some pain and swelling in the first few days. This is normal. We manage this with medication and by keeping your hand elevated. As the swelling settles, you will notice the discomfort easing.
We use a thumb spica splint to protect your hand. You must keep this on for four to six weeks. Do not drive while wearing the splint. It stops you from gripping the steering wheel safely. You can drive again once the splint is removed and your surgeon clears you. Learn more about driving after upper-limb surgery.
Your recovery involves gentle hand therapy with Ruby Doolan at Extend Rehabilitation. These exercises help restore movement and strength. You will start with simple motions at home. As your thumb moves more freely, you can return to daily tasks. We preserve your key pinch strength, so you can grip objects again.
Your timeline may differ; your surgeon and physio will guide you.
What can go wrong
Most patients do well, but problems can occasionally happen. Your surgeon and the team monitor you closely to spot any issue early.
If you have wear-and-tear arthritis in the small joint at the base of your thumb, you need to be careful with high-load activities. This includes sports like tennis that require you to push down on your wrist while it is bent back. These movements put heavy stress on the joint. If you plan to continue these activities, this surgery may not be suitable for you. Pushing through pain in this way can cause significant discomfort and may damage the repair.
If you feel deep pain or instability when trying to play tennis or perform similar tasks, stop immediately. Do not try to push through the pain. Contact your surgeon’s team to discuss whether these activities are safe for your specific recovery stage. They can advise you on when it is safe to return to high-impact sports or if you need to modify your routine permanently.
The complications table on this page lists typical rates if you want the specifics.
When to call us
Call us if you have a fever, increasing redness or discharge from your wound, or sudden severe pain. Go to emergency if you notice calf swelling, shortness of breath, loss of sensation, or cannot move your limb. These signs need urgent assessment. We are here to help you stay safe during your recovery. Contact our clinic immediately if any of these symptoms occur.
