Patients › Hand

Pyrocarbon interposition arthroplasty

PDF Evidence Consent

Updated Oct 2026

A pyrocarbon implant resurfacing an arthritic joint. Kieran Hirpara 4.0

Why this operation has been suggested

Dr Kieran Hirpara, an upper-limb surgeon at Mater Private Hospital Rockhampton, starts with the least invasive options that suit your condition. Patients are generally referred to our clinic by their GP; if a physiotherapist has suggested you see us, you will still need a referral from your GP in order to be eligible for the Medicare rebate. At your appointment we take a history, examine your hand, and arrange imaging if it is needed to confirm the diagnosis.

This operation replaces the worn surface of a small joint with a smooth, shaped piece of carbon. It is usually offered for long-standing arthritis that has not settled with activity change, hand therapy, or splinting. We usually try non-operative care first and consider surgery when that has not given enough improvement. For some structural problems, surgery may be recommended straight away.

The operation aims to relieve pain while keeping the joint moving. It also aims to keep the natural height of the thumb and preserve pinch and grip strength. For the thumb joint at the base, 91% of implants are still working well at medium-term follow-up. We will talk through this option with you and decide together whether it suits your hand and your goals.

Before the operation

In the seven hours before your operation, do not eat or drink anything. We ask for seven hours rather than six so your surgery can be brought forward if the theatre list runs early. Your surgeon will tell you which of your usual medicines to stop and when, and it helps to bring a written list of everything you take. Arrange for someone to drive you home afterwards, and wear loose, comfortable clothing. X-rays are usually all we need to plan the operation, though an MRI or ultrasound scan is sometimes used as well. If you have other medical conditions, you may need blood tests or a review with the anaesthetist, the doctor who gives the anaesthetic. Most patients need neither.

On the day

You arrive at the hospital's surgical admissions unit, where you are checked in and prepared for theatre. You will meet the anaesthetist, the doctor who looks after your anaesthetic. 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 taken into the operating theatre, where the operation is performed. Afterwards you wake up in the recovery area, where nurses watch over you while the anaesthetic wears off. Once you are stable, you either go to a ward or go home, depending on the procedure and how your recovery is going.

What the operation involves

Your surgeon makes a single cut over the area of your hand being operated on. Through this opening, they remove the worn, damaged surfaces of the joint. In place of the worn surfaces, they fit a smooth, shaped piece of carbon that sits between the bones. This spacer takes over the job of the worn joint surface, so the bones glide smoothly instead of grinding on each other.

For the thumb joint at the base of your hand, your surgeon keeps the natural height of the thumb by placing the spacer between the bones. The joint is then repaired and supported so it heals in a good position. Your thumb may be held still in a straight position while it heals.

The cut is closed with stitches. A dressing goes over the wound, and our team will tell you how to care for it in the first days.

After the operation

Most patients stay one night in hospital after this operation, though some are able to go home the same day. You wake up in the recovery area, then move to the ward. Nurses will keep you comfortable and give you pain medicine if you need it. Your hand will be in a dressing and a splint, which protect the operation while it heals. You can get out of bed and move around as soon as you feel steady. Please arrange for someone to stay with you for the first 24 hours at home. We leave the dressing on for about 10 days; please do not take it off before then unless we tell you to. We change or remove it when we see you.

Recovery

Expect some pain and swelling in your hand during the first days and weeks. This is a normal part of healing and settles gradually. Keeping your hand raised when you are resting helps, and the pain medicine we give you will ease the discomfort. Most people find the worst of the pain passes early, and comfort improves steadily from there.

Your hand will be in a dressing and a splint, which protect the joint while it heals. We leave the dressing on for about 10 days and change or remove it when we see you. Rehabilitation after hand surgery is hand therapy, not physiotherapy. Your hand therapy after surgery is with Ruby Doolan at Extend Rehabilitation. Ruby is a hand therapist: she will guide your exercises and make any splint you need as your hand recovers. Early on, the exercises are gentle and focus on keeping swelling down. As movement returns, they build up to restore bending, straightening and grip.

You will be able to manage light daily tasks around the home within the limits of your splint. You will not be able to grip, pinch or lift with the operated hand while it is held still. Once the splint is removed and your surgeon clears you, you can start using the hand more normally, and driving can follow. See our page on Driving after upper-limb surgery for the details.

Recovery varies between individuals. Your timeline may differ, and your surgeon and therapist will guide you along the way.

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.

Sometimes the implant changes position or settles into the bone. You might notice new pain in the joint, a feeling that the finger or thumb is not sitting straight, or a change in how it moves. If you notice any of these, bring them up at your next review.

The implant can also loosen. This usually feels like pain that returns after a good stretch of improvement, often worse when you grip or pinch. Tell your surgeon if this happens.

Stiffness can develop in the joint. The finger or thumb may not bend or straighten as far as it did, and the tendon on the back of the joint can become stuck down by scar tissue. Mention this at your review so your therapist can adjust your exercises.

The joint can become unstable or the original deformity can come back. You may see the finger drifting out of line again. Raise this at your next appointment.

Infection is uncommon but needs quick attention. Call the clinic the same day if you have a fever, spreading redness around the wound, or fluid or pus leaking from it. Pain that keeps getting worse despite your pain medicines also means you should call the clinic the same day.

Nearby structures can be irritated or injured during this type of surgery. A nerve near the thumb can become sensitive, giving tingling or altered feeling in the skin. The artery on the thumb side of the wrist, or a tendon at the front of the wrist, can be affected. If you notice numbness or cannot move your fingers once the nerve block has worn off, at about 24 hours, call the clinic. Numbness and weakness in the first 24 hours after a nerve block are expected.

A bone in the hand can occasionally break during or after surgery. This causes sudden pain and swelling. Call the clinic if this happens.

If an implant fails and cannot be saved, other operations can help. The implant can be removed and the joint treated another way, which reliably eases pain. In rare cases the joint can be fused, meaning it is permanently stiffened, or the finger may need to be removed.

The complications table on this page lists typical rates if you want the specifics.

When to call us

Most problems show up early, and quick action makes them easier to sort out. Call the clinic the same day if you have a fever, spreading redness around the wound, or fluid or pus leaking from it. Call the clinic the same day too if pain keeps getting worse despite your pain medicines. Call the clinic if you notice numbness or cannot move your fingers once the nerve block has worn off, at about 24 hours. Numbness and weakness in the first 24 hours after a nerve block are expected.

Go to the emergency department if you have calf swelling or pain, or shortness of breath or chest pain. These can be signs of a blood clot. Go to the emergency department if your fingers, hand or thumb turn pale, cold, white, blue or dark. This can be a circulation problem.

If you cannot reach the clinic, out of hours or on a weekend, go to your nearest emergency department.

Where to read more about the condition

This page is about the operation itself. The condition it treats, including what the evidence shows about when surgery helps and when it does not, is covered in more detail on the Basal Thumb Arthritis page.

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Reviewed by Dr Kieran Hirpara · 10 June 2026.

Want the clinical detail? Read the clinician version.

Talk to your treating clinician for advice specific to you.

For an appointment with the CQ Hand + Upper Limb team, ask your GP about a referral or visit www.cqupperlimb.com.

Evidence & references

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Overview

• Pyrocarbon interpositional arthroplasty provided pain relief and high patient satisfaction with good implant longevity in a study with minimum 8-year follow-up [1].
• Partial trapeziectomy with pyrocarbon arthroplasty may prove to be a successful option for the treatment of trapeziometacarpal joint osteoarthritis, providing excellent pain relief and high patient satisfaction [2].
• PyroCarbon implant hemiarthroplasty is a promising surgical technique for stages II and III trapeziometacarpal arthritis and can provide a stable, mobile, and pain-free joint [3].
• The Pyrocardan implant is not superior to other arthroplasty methods and has a high complication rate [4].
• The Pyrocardan implant appears as a simple alternative to the Dubert procedure for ulnar carpo-metacarpal osteoarthritis, particularly in cases involving the 4th ray [5].
• The PyroDisk implant for treating advanced trapeziometacarpal arthritis did not demonstrate superiority over published outcome data of trapeziectomy with or without ligament reconstruction and tendon interposition [6].
• The good functional and radiographic outcomes, and the absence of surgical complications are evidence that the Pyrocardan resurfacing implant is a valid option for treating STT osteoarthritis [7].
• Arthroplasty is recommended for patients with post-trauma painful PIP joints [8].
• Active patients, under 65 years of age with Eaton-Littler stage III osteoarthritis of the thumb CMC joint who are treated with anatomic pyrolytic carbon resurfacing hemiarthroplasty and stabilisation may achieve sustained improvement in pain and hand function for up to 6.5 years [9].
• The insertion of pyrolytic carbon implants for PIPJ arthroplasty is a technically demanding procedure, but it has the potential to achieve pain relief, stability, satisfactory ROM, and correction of the deformity [10].
• The results of pyrolytic carbon PIPJ arthroplasty in review were unpredictable and may not be superior to those achieved with other methods of arthroplasty [10].
• A study with long-term follow-up after pyrocarbon disc interposition for the treatment of CMC1 osteoarthritis grade 2 to 3 in more than 150 thumbs was conducted [11].
• The PyroDisk interposition arthroplasty confirmed good 5-year clinical results [12, 13].
• PyroDisk interposition has merit in patients with early disease unresponsive to conservative measures, in whom trapeziectomy may be considered too destructive and hemi or total arthroplasty overzealous [14].
• The good results, the simple surgical procedure, the absence of complications, and the lack of a need for any fixation or ligamentoplasty confirm the advantages of this pyrocarbon implant in the treatment of STT arthrosis [15].
• All subjective and objective outcomes were similar following LRTI and pyrolytic interpositional arthroplasty in patients with TMC arthritis, except pinch strength, which was more improved following pyrolytic interpositional arthroplasty [16].
• The encouraging mid-term clinical results of the interposition implant (APSI) in the context of proximal pole scaphoid pseudarthrosis make this technique a proven alternative, without precluding a definitive therapeutic option in case of failure [18].
• The Pyrocardan implant may be contraindicated in patients with symptomatic STT OA who intend to continue high-load activities, particularly those involving wrist extension under load, such as tennis [20].

Anatomy & Pathophysiology

Bony Anatomy

• The skeleton of the hand and wrist consists of 27 bones, of which 19 are long bones [28].
• The radial ray or first ray is the shortest, made up of only three bones: a metacarpal and two phalanges [28].
• The trapezium is clearly angled out in front of the carpal plane so that the first metacarpal makes an angle of about 45 degrees with the second metacarpal in the sagittal plane [28].
• The thumb metacarpal is the shortest, while the index metacarpal is by far the longest [28].
• The epiphyseal plates are located at the proximal ends of the phalanges and the first metacarpal, whereas they are located at the distal ends of the other metacarpals [28].
• The thumb metacarpal is independent and articulates with the trapezium [35].
• The index metacarpal is the most firmly fixed [35].
• The ring metacarpal has about 10 degrees of mobility in flexion and extension [35].
• The fifth metacarpal has a range of flexion–extension of approximately 20 degrees [35].

Soft Tissue & Vascular Anatomy

• The extrinsic extensors run through six different fibroosseous retinacular compartments at the wrist level [27].
• The first (most radial) compartment contains the abductor pollicis longus and the extensor pollicis brevis [27].
• The second extensor compartment contains the extensor carpi radialis longus and the extensor carpi radialis brevis [27].
• The third compartment contains the extensor pollicis longus, which turns abruptly radialward about Lister tubercle [27].
• The fourth extensor compartment contains the extensor indicis proprius lying deep to the four tendons of the extensor digitorum communis [27].
• The fifth compartment contains the extensor digiti quinti [27].
• The sixth compartment contains the extensor carpi ulnaris tendon, which inserts at the base of the little finger metacarpal [27].
• The extrinsic finger flexors are the flexor digitorum profundus and the flexor digitorum superficialis [27].
• The flexor digitorum profundus inserts on the proximal volar aspect of the distal phalanx [27].
• The flexor digitorum superficialis acts as a flexor of the proximal interphalangeal and metacarpophalangeal joints [27].
• There are seven interosseous muscles, four dorsal and three volar [32].
• The dorsal interossei are abductors [32].
• The volar interossei are adductors [32].
• The middle finger has two dorsal interossei (abductors) and no volar interossei (adductors) because the central axis of the hand lies within it [32].
• The "princeps pollicis" artery is the terminal branch of the radial artery and crosses the first intermetacarpal space [36].
• The princeps pollicis runs along the ulnar side of the first metacarpal bone and along the volar surface of the adductor muscle [36].
• The princeps pollicis divides into two terminal rami, namely the collateral palmar arteries of the thumb, at the level of the cutaneous flexion crease of the metacarpophalangeal joint [36].
• An arcade located deep in the flexor tendon joins together the two arteries at the level of the distal metaphysis of the first phalanx [36].
• The dorsal arteries of the thumb originate from the palmar arteries (princeps, commissural or anastomoses of the superficial arcade) at the level of the first metacarpal [36].

Functional Mechanics

• The wrist has three axes of movement, permitting the hand to be positioned in any spatial configuration [28].
• The thumb ray is more mobile, shorter, and more proximal than the other rays, allowing it to project in front of the plane of the palm to oppose itself to the other four rays [28].
• The skeleton of the hand presents a longitudinal and transverse concavity, giving it the shape of a cup with a palmar concavity when the thumb is placed next to the index finger [28].
• The transverse axis of the palm forms an acute angle of approximately 75 degrees with the longitudinal axis [28].
• The metacarpal arch is endowed with a great deal of adaptability because of the mobility of the peripheral metacarpals [35].
• The heads of the second and third metacarpals are fixed [35].
• The mobility of the ulnar metacarpals allows "flexion" of 10 degrees for the fourth metacarpal, and "flexion" of 20 degrees for the fifth metacarpal [35].
• The keystones of the longitudinal arches are the metacarpophalangeal articulations, whose thick anterior glenoid capsules, the volar plates, prevent hyperextension [35].
• The dorsal skin slides distally to allow metacarpophalangeal joint flexion [40].
• Interphalangeal flexion is accomplished by means of a special arrangement of skin folds on the dorsum of each articulation [40].
• The gliding mechanism for tendons in narrow crowded areas is assured by the synovial sheath, which allows a considerable amplitude of movement [40].
• The fibrous sheath assumes the role of a pulley when the tendon changes direction [40].
• The position of each articulation depends on the equilibrium of forces acting at that level, and this equilibrium is subject to the position of the immediately proximal articulation [40].
• Single articular movements around a fixed perpendicular axis simply do not exist in the hand [40].
• Almost all movements in the hand are around oblique and variable axes, resulting in combined movements permitting optimal orientation of the phalanges at the time of prehension [40].

Indications and Disease Staging

• PyroCarbon implant hemiarthroplasty is a promising surgical technique for stages II and III trapeziometacarpal arthritis [3].
• The Pyrocardan resurfacing implant is a valid option for treating scaphotrapeziotrapezoid (STT) osteoarthritis [7].
• The pyrocarbon implant is indicated for the treatment of STT arthrosis [15].
• The pyrocarbon interposition implant (APSI) is an alternative for the treatment of proximal pole scaphoid pseudarthrosis [18].
• The Pyrocardan implant may be contraindicated in patients with symptomatic STT osteoarthritis who intend to continue high-load activities, particularly those involving wrist extension under load, such as tennis [20].

Patient Selection and Demographics

• Active patients under 65 years of age with Eaton-Littler stage III osteoarthritis of the thumb CMC joint are candidates for anatomic pyrolytic carbon resurfacing hemiarthroplasty and stabilisation [9].
• Pyrocarbon disc interposition is used for the treatment of CMC1 osteoarthritis grade 2 to 3 [11].
• Total trapezectomy associated with the placement of a NuGrip pyrocarbon implant is a procedure for the replacement of the TMC joint [22].

Comparative Classification and Efficacy

• The insertion of pyrolytic carbon implants for PIPJ arthroplasty has the potential to achieve pain relief, stability, satisfactory ROM, and correction of the deformity; however, the results in this review were unpredictable and may not be superior to those achieved with other methods of arthroplasty [10].

Clinical Presentation

• Pyrocarbon interpositional arthroplasty is indicated for trapeziometacarpal osteoarthritis [1].
• Pyrocarbon interpositional arthroplasty is indicated for trapeziometacarpal joint osteoarthritis [2].
• PyroCarbon implant hemiarthroplasty is a surgical technique for stages II and III trapeziometacarpal arthritis [3].
• The Pyrocardan implant is used for trapeziometacarpal osteoarthritis [4].
• The Pyrocardan implant is used for ulnar carpo-metacarpal osteoarthritis, particularly in cases involving the 4th ray [5].
• The PyroDisk implant is used for advanced trapeziometacarpal arthritis [6].
• The Pyrocardan resurfacing implant is used for scaphotrapeziotrapezoid (STT) osteoarthritis [7].
• Pyrocarbon PIP arthroplasty is used for post-trauma painful joints [8].
• Anatomic pyrolytic carbon resurfacing hemiarthroplasty is used for Eaton-Littler stage III osteoarthritis of the thumb CMC joint in patients under 65 years of age [9].
• Pyrolytic carbon implants are used for proximal interphalangeal joint (PIPJ) arthroplasty [10].
• Pyrocarbon disc interposition is used for CMC1 osteoarthritis grade 2 to 3 [11].
• PyroDisk interposition arthroplasty is used for trapeziometacarpal osteoarthritis [12].
• PyroDisk interposition is indicated for patients with early disease unresponsive to conservative measures, in whom trapeziectomy may be considered too destructive and hemi or total arthroplasty overzealous [14].
• The pyrocarbon implant is used for STT arthrosis [15].
• Pyrolytic interpositional arthroplasty is used for TMC arthritis [16].
• Pi2 pyrocarbon spacer arthroplasty is used for carpometacarpal joint osteoarthritis [17].
• The interposition implant (APSI) is used for pseudarthrosis of the proximal pole of the scaphoid [18].
• A pyrocarbon implant is used for Kienböck disease [19].
• Total trapeziectomy associated with the placement of a pyrocarbon type Nugrip implant is used after replacement of the TMC joint [22].
• The Pyrocardan implant is used for stage 2 trapeziometacarpal osteoarthritis [23].
• The Pi2 pyrocarbon implant is used in total trapeziectomy and suspension ligamentoplasty [24].
• The Pi2 pyrocarbon implant is used in destructions of the capitolunate joint space [25].

Investigations

• Clinical evaluation of the hand and wrist requires combining patient history with a careful physical examination to pinpoint or narrow the scope of possible pathologic processes [26].
• Diagnostic tests such as imaging and serum laboratory studies are useful in determining hand pathology but can be expensive, time-consuming, and often nonspecific [26].
• A systematic method to approaching the physical examination of the hand is essential due to the number of structures in a small space [26].

Treatment

Trapeziometacarpal Joint Osteoarthritis

• Pyrocarbon interpositional arthroplasty provided pain relief and high patient satisfaction with good implant longevity in a minimum 8-year follow-up study [1].
• Partial trapeziectomy with pyrocarbon arthroplasty provides excellent pain relief and high patient satisfaction for trapeziometacarpal joint osteoarthritis [2].
• PyroCarbon implant hemiarthroplasty is a promising surgical technique for stages II and III trapeziometacarpal arthritis that can provide a stable, mobile, and pain-free joint [3].
• The Pyrocardan implant is not superior to other arthroplasty methods and has a high complication rate for trapeziometacarpal osteoarthritis [4].
• Long-term follow-up data for pyrocarbon disc interposition for the treatment of CMC1 osteoarthritis grade 2 to 3 is available in a study involving more than 150 thumbs [11].
• Interposition arthroplasty with PyroDisk confirmed good 5-year clinical results [12, 13].
• The modified procedure of partial trapeziectomy and pyrocarbon interpositional arthroplasty improves functional results by increasing active and passive range of movement at the TMCJ, providing joint stability and pain relief comparable to standard techniques, while preserving thumb length and key pinch strength [29].
• Pyrocarbon interposition arthroplasty for trapeziometacarpal osteoarthritis does not preclude subsequent conventional arthroplasty techniques in the event of failure [23].

Scaphotrapeziotrapezoid Joint Osteoarthritis

• The Pyrocardan resurfacing implant is a valid option for treating STT osteoarthritis, evidenced by good functional and radiographic outcomes and the absence of surgical complications [7].
• The good results, simple surgical procedure, absence of complications, and lack of need for fixation or ligamentoplasty confirm the advantages of the pyrocarbon implant in the treatment of STT arthrosis [15].

Other Indications

• Pyrocarbon PIP arthroplasty is recommended for post-trauma painful joints [8].
• The insertion of pyrolytic carbon implants for PIPJ arthroplasty is a technically demanding procedure with the potential to achieve pain relief, stability, satisfactory ROM, and correction of deformity, though results were unpredictable and may not be superior to other methods of arthroplasty [10].
• Range of motion improved after Pi2 pyrocarbon spacer arthroplasty in carpometacarpal joint osteoarthritis, especially in opposition with a mean Kapandji score of 9.60, with no major aggravation of metacarpophalangeal extension [17].
• The interposition implant (APSI) for proximal scaphoid pseudarthrosis provides encouraging mid-term clinical results and serves as a proven alternative without precluding a definitive therapeutic option in case of failure [18].
• There were no changes in range of motion after surgery for Kienböck disease treated with a pyrocarbon implant, and the average grip strength was 76.5% of the contralateral side [19].

Complications

• The Pyrocardan implant has a high complication rate [4].
• The Pyrocardan resurfacing implant for STT osteoarthritis was associated with the absence of surgical complications [7].
• The pyrocarbon implant for STT arthrosis was associated with the absence of complications [15].

Recovery

• Range of motion improved after Pi2 pyrocarbon spacer arthroplasty, especially in opposition, with a mean Kapandji score of 9.60 [17].
• There was no major aggravation of metacarpophalangeal extension following Pi2 pyrocarbon spacer arthroplasty [17].
• The average grip strength was 76.5% of the contralateral side after pyrocarbon implant treatment for Kienböck disease [19].
• There were no changes in range of motion after surgery for Kienböck disease treated with a pyrocarbon implant [19].

Key Evidence

• [L4] Pyrocarbon interpositional arthroplasty provided pain relief and high patient satisfaction with good implant longevity. [1] (10.1177/1753193420906805)
• [L3] Partial trapeziectomy with pyrocarbon arthroplasty may prove to be a successful option for the treatment of trapeziometacarpal joint osteoarthritis, providing excellent pain relief and high patient satisfaction. [2] (10.1177/1753193413519384)
• [L4] PyroCarbon implant hemiarthroplasty is a promising surgical technique for stages II and III trapeziometacarpal arthritis and can provide a stable, mobile, and pain-free joint. [3] (10.1097/bth.0b013e318271aab7)
• [L4] The study concludes that the Pyrocardan implant is not superior to other arthroplasty methods and has a high complication rate. [4] (10.1016/j.hansur.2016.09.004)
• [L4] The Pyrocardan implant appears as a simple alternative to the Dubert procedure for ulnar carpo-metacarpal osteoarthritis, particularly in cases involving the 4th ray. [5] (10.1016/j.hansur.2018.10.044)
• [L4] The PyroDisk implant for treating advanced trapeziometacarpal arthritis did not demonstrate superiority over published outcome data of trapeziectomy with or without ligament reconstruction and tendon interposition. [6] (10.1016/j.jhsa.2014.07.011)
• [L3] The good functional and radiographic outcomes, and the absence of surgical complications are evidence that the Pyrocardan1 resurfacing implant is a valid option for treating STT osteoarthritis. [7] (10.1016/j.hansur.2017.01.003)
• [L4] We recommend arthroplasty for this group of patients. [8] (10.1016/s0363-5023(03)80384-2)
• [L3] Active patients, under 65 years of age with Eaton-Littler stage III osteoarthritis of the thumb CMC joint who are treated with anatomic pyrolytic carbon resurfacing hemiarthroplasty and stabilisation may achieve sustained improvement in pain and hand function for up to 6.5 years. [9] (10.1142/s2424835518500443)
• [L4] The insertion of pyrolytic carbon implants for PIPJ arthroplasty is a technically demanding procedure, but it has the potential to achieve pain relief, stability, satisfactory ROM, and correction of the deformity; however, the results in this review were unpredictable and may not be superior to those achieved with other methods of arthroplasty. [10] (10.1016/j.jhsa.2006.02.018)
• [L4] This is the first study with long-term follow-up after pyrocarbon disc interposition for the treatment of CMC1 osteoarthritis grade 2 to 3 in more than 150 thumbs. [11] (10.1016/j.jhsa.2018.06.086)
• [L4] Our study confirms the good 5-year clinical results of interposition arthroplasty with PyroDisk. [12] (10.1177/1558944716660555n)
• [L4] Our study confirms the good 5-year clinical results of interposition arthroplasty with PyroDisk. [13] (10.1177/1558944716660555m)
• [L4] PyroDisk interposition has merit in patients with early disease unresponsive to conservative measures, in whom trapeziectomy may be considered too destructive and hemi or total arthroplasty overzealous. [14] (10.1177/1753193420981552)
• [L4] The good results, the simple surgical procedure, the absence of complications, and the lack of a need for any fixation or ligamentoplasty confirm the advantages of this pyrocarbon implant in the treatment of STT arthrosis. [15] (10.1016/j.main.2005.04.010)
• [L3] All subjective and objective outcomes were similar following LRTI and pyrolytic interpositional arthroplasty in patients with TMC arthritis, except pinch strength, which was more improved following pyrolytic interpositional arthroplasty. [16] (10.1155/2019/7961507)
• [L3] Range of motion improved, especially in opposition (mean Kapandji score, 9.60), with no major aggravation of metacarpophalangeal extension. [17] (10.1016/j.hansur.2016.05.002)
• [L4] Les résultats cliniques encourageants à moyen terme de l’implant d’interposition (APSI), dans le cadre d’une pseudarthrose du pôle proximal du scaphoïde, font de cette technique une alternative probante, sans interdire une option thérapeutique définitive en cas d’échec. [18] (10.1016/j.main.2011.10.031)
• [L5] There were no changes in range of motion after surgery and the average grip strength was 76.5% of the contralateral side. [19] (10.1016/j.main.2014.09.002)
• [Case_report] The Pyrocardan implant may be contraindicated in patients with symptomatic STT OA who intend to continue high-load activities, particularly those involving wrist extension under load, such as tennis. [20] (10.1016/j.jhsg.2026.100964)
• [L4] La trapézectomie totale associée à la mise en place d'un implant en pyrocarbone type Nugrip après le remplacement de l'articulation TMC semble être une procédure attrayante. [22] (10.1016/j.hansur.2018.10.166)
• [L3] Il ne coupe pas les ponts en cas d'éventuel échec à des techniques d'arthroplastie plus conventionnelles. [23] (10.1016/j.main.2011.10.132)
• [L3] The implant Pi2 seems to contribute keeping trapezial height, without functional advantages and with a risk of dislocation. [24] (10.1016/j.main.2013.04.003)
• [L4] Cette technique a l'avantage de préserver les mobilités médio-carpiennes et les ligaments extrinsèques du poignet. [25] (10.1016/j.hansur.2016.10.125)
• [L4] The modified procedure improves functional results by increasing active and passive range of movement at the TMCJ, providing joint stability and pain relief comparable to standard techniques, while preserving thumb length and key pinch strength. [29] (10.1177/1753193414553368)

References

[1] Partial trapeziectomy and pyrocarbon interpositional arthroplasty for trapeziometacarpal osteoarthritis: minimum 8-year follow-up. Journal of Hand Surgery (European Volume). 2020. DOI: 10.1177/1753193420906805

[2] Partial trapeziectomy and pyrocarbon interpositional arthroplasty for trapeziometacarpal joint osteoarthritis: results after minimum 2 years of follow-up. Journal of Hand Surgery (European Volume). 2014. DOI: 10.1177/1753193413519384

[3] PyroCarbon Implant Hemiarthroplasty for Trapeziometacarpal Arthritis. Techniques in Hand & Upper Extremity Surgery. 2013. DOI: 10.1097/bth.0b013e318271aab7

[4] Early outcomes of Pyrocardan® implants for trapeziometacarpal osteoarthritis. Hand Surgery and Rehabilitation. 2016. DOI: 10.1016/j.hansur.2016.09.004

[5] L’implant en Pyrocarbone (Pyrocardan®) dans le traitement de l’arthrose carpo-métacarpienne ulnaire post-traumatique. Hand Surgery and Rehabilitation. 2018. DOI: 10.1016/j.hansur.2018.10.044

[6] Pyrocarbon Interposition (PyroDisk) Implant for Trapeziometacarpal Osteoarthritis: Minimum 5-Year Follow-Up. The Journal of Hand Surgery. 2014. DOI: 10.1016/j.jhsa.2014.07.011

[7] Treatment of scaphotrapeziotrapezoid osteoarthritis with the Pyrocardan® implant: Results with a minimum follow-up of 2 years. Hand Surgery and Rehabilitation. 2017. DOI: 10.1016/j.hansur.2017.01.003

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