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Patients › Wrist

Distal Radioulnar Joint Surgery

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Updated Sep 20264 citations
Illustration: Distal Radioulnar Joint Surgery

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 wrist, and arrange imaging where it is needed to work out what is causing your pain.

The distal radioulnar joint is the joint between the two bones of your forearm, just above the wrist. Surgery on it is suggested when that joint is worn, unstable, or damaged after an injury, and it is causing pain on the little-finger side of your wrist, trouble turning your forearm, or weaker grip. For long-standing problems we usually try non-operative care first: activity change, physiotherapy or hand therapy, and splinting. Surgery comes into the picture when those steps have not given you enough improvement. Some injuries to this joint are unstable from the start, and for those we may recommend surgery straight away. The aim of the operation is to ease your pain and let you turn your forearm and use your hand with more comfort and confidence.

Before the operation

Once your surgery is booked, we will give you clear instructions to prepare. You will need to stop eating and drinking seven hours before your operation. We ask for seven hours rather than a shorter time so your place on the theatre list can be brought forward if the day runs early. If you take regular medicines, bring a written list of them to hospital, and we will tell you which ones to pause and when. Most people do not need any extra tests beforehand. If you have other medical conditions, you may need blood tests or a review with the anaesthetist, the doctor who gives your anaesthetic. Please arrange for someone to drive you home afterwards, and wear loose, comfortable clothing on the day.

On the day

On the day of your operation you come to the hospital's surgical admissions unit. There 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. A regional nerve block is sometimes added for post-operative pain relief; the anaesthetist will discuss this with you on the day.

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

There is more than one way to operate on this joint, and the right one for you depends on what is wrong with it. If the joint has come out of place after a wrist fracture, your surgeon will put the bones back into their correct position and hold them there while they heal, sometimes with a cast. If the joint is worn and painful, your surgeon may remove part of the bone at the end of the forearm bone on the little-finger side of your wrist. This is done through a cut over the back of the wrist, on the little-finger side. Removing that worn bone surface stops the two forearm bones grinding on each other when you turn your forearm.

If the joint is loose rather than worn, your surgeon can rebuild the ligaments that hold it together. Ligaments are the strong bands of tissue that connect one bone to another. This is done using a piece of tendon, the tissue that joins muscle to bone, woven through small holes in the bones to act like a new strap holding the joint in place. This is only possible when the joint surfaces themselves are still healthy.

If the whole joint is badly worn, your surgeon may replace it. The damaged bone at the end of the forearm bone is removed and replaced with an artificial joint made of metal, and sometimes plastic parts as well, so the two forearm bones can move smoothly against each other again.

At the end of the operation your surgeon closes the cut with stitches and covers it with a dressing. You will wake up with your hand and wrist bandaged, and the dressing stays on for about 10 days.

After the operation

When you wake up you will be in the recovery area, and nurses will check on you as the anaesthetic wears off. Your hand and wrist will be bandaged, and you may have a sling to rest your arm. We will give you pain relief to keep you comfortable; tell the nurses if your pain is not settling. You can get up and move around as soon as you feel able, and someone should stay with you for the first 24 hours. Your team will tell you whether you go home the same day or stay one night in hospital. 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

For the first few days your wrist will be sore and swollen, and the little-finger side may throb, especially at night. Keeping your hand raised on pillows, even while you sleep, helps the swelling settle. The pain relief we give you works best when you take it regularly rather than waiting for the pain to build.

You will leave hospital with your arm bandaged and resting in a sling. The dressing stays on for about 10 days, and we will change or remove it when we see you. Your rehabilitation 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. Early on, the exercises are gentle and focus on keeping your fingers, elbow and shoulder moving. As healing progresses, the exercises work on turning your forearm and building your grip back up.

Day to day, you will need help at first with tasks that need two hands, like dressing, cooking and carrying things. Once the swelling settles and movement returns, everyday activities get easier. When you can grip without pain and turn your forearm comfortably, you will find you can do more with your hand. If driving is part of your recovery, you must not drive while in a sling or splint, while on strong pain medication, or unless you can hold the wheel with both hands and react in an emergency stop. See our guide on driving after upper-limb surgery.

Everyone heals at their own pace, and your timeline may differ. Your surgeon and your hand therapist will guide you at each step.

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 part of the end of your forearm bone has been removed, the remaining stump can sometimes shift or press against nearby structures. You might feel a sharp or grinding pain on the little-finger side of your wrist when you turn your forearm, or a sense that something is catching. Bring this up at your next review.

Some people notice the wrist is less painful but stiffer afterwards, with less bending forwards. If turning your forearm feels limited, your shoulder often takes over without you realising, so the difference in daily life may be small. Mention any movement you are unhappy with at review.

If this joint was injured along with a wrist fracture, the joint can slip out of place early on, sometimes within the first two weeks. This is easy to miss. Watch for new pain, swelling or a change in the shape of your wrist, and tell the clinic if you notice these.

A tear in the cartilage cushion on that side of the wrist, left untreated, can leave the joint feeling loose. You might notice clicking, a shift or clunk when you load the wrist, or weaker grip. If the joint stays loose and painful despite other treatment, further surgery is sometimes needed, but many people improve with time and do not need another operation. Ulnar-sided wrist symptoms often keep improving for up to a year after fracture surgery.

For a long-standing wrist deformity present since youth, the joint can gradually become worn or unstable over time. In severe cases, the tendons that straighten the fingers can wear through from rubbing over a prominent bone, causing sudden loss of the ability to straighten one or more fingers. If a finger will not straighten, contact the clinic promptly.

As with any wrist operation, bones can be slow to heal or fail to join, and the area where bone was removed can become unstable and painful. Persistent pain at the back of the wrist should be raised at review.

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, or the skin around your wound becomes more red, swollen or weepy. Call us if your pain suddenly gets worse, or new pain or swelling appears in your wrist in the first two weeks. Tell us if a finger will not straighten, or your wrist feels loose, clicks or gives way. Go to emergency if you have calf swelling or pain, shortness of breath, chest pain, numbness in your hand, or you cannot move your arm or fingers.

In more depth

Advanced reading: the deeper science (optional)

This section goes further than you need for your own treatment decisions. The distal radioulnar joint is worth the extra reading because it is the joint in the wrist we are worst at measuring, the one most often blamed prematurely, and the one where waiting is most often the right answer.

We cannot reliably measure the problem

Instability of this joint is diagnosed largely by feel, the examiner shifts the ulna against the radius and forms an impression. A 2025 review of assessment strategies concluded plainly that reliable, quantifiable methods for analysing distal radioulnar joint instability remain an unmet need, and that developing them is essential to improving management [1].

That has a direct consequence for you. When the diagnosis rests on a subjective test, the threshold for calling a joint unstable varies between examiners, and so does the threshold for operating on it. A second opinion here is not distrust; it is a reasonable response to a test with known limits.

Most ulnar-sided pain after a wrist fracture settles

This is the single most useful finding for anyone with a painful wrist after a distal radius fracture. A comprehensive review concluded that most ulnar-sided wrist problems following distal radial fractures can be treated non-operatively initially, typically for over a year, in anticipation of substantial improvement with time [2].

A year is longer than most people expect to be told to wait, and the temptation to intervene earlier is strong on both sides of the consultation. The exception named in the same review is important and specific: early marked subluxation of the joint that physically blocks forearm rotation does need addressing rather than observing [2].

So the default is patience, with a defined reason to abandon it.

When salvage is needed, the choice is finer than it looks

If the joint is destroyed and non-operative management has genuinely failed, the classic options are the Darrach procedure, removing the end of the ulna, and the Sauvé-Kapandji, which fuses the joint and creates a gap more proximally to allow rotation.

A systematic review comparing them found comparable satisfaction regardless of the underlying pathology, with similar improvement in range of motion, strength and overall function [3]. The difference was in the reoperation rate, which was higher with the Sauvé-Kapandji [3].

That is a clean discriminator. Where two operations produce the same result, the one requiring fewer further operations has the advantage, though the Sauvé-Kapandji retains a role where preserving the ulnar support of the carpus matters, which is precisely why it was devised.

Ulnar impaction is a different problem with its own answer

Ulnar-sided pain from the ulna being relatively too long, ulnar impaction syndrome, is treated by shortening the load path, either by cutting and shortening the ulnar shaft or by arthroscopically removing the dome of the ulnar head. A meta-analysis of 311 patients found both effective, with the arthroscopic wafer procedure showing fewer complications and a lower reoperation rate [4].

The shaft osteotomy involves a plate, a healing bone and the possibility of the osteotomy failing to unite; the arthroscopic procedure avoids all three. Where the anatomy suits it, that is a meaningful difference.

Reviewed by Dr Kieran Hirpara · 13 August 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.

References for the advanced reading
  1. Christy M, Wright DJ, Goldfarb CA. Assessment strategies for distal radioulnar joint instability: current state and a need for improved tools. J Hand Surg Am. 2025;50(12):1505-14.
  2. Giddins G. The distal radioulnar joint after distal radial fractures: when and how do we need to treat pain, stiffness or instability? J Hand Surg Eur Vol. 2023;48(3):230-45.
  3. Lamont S, Debkowska M, Johnsen P, Froehle A, Cotterell IH, Isaacs J. Outcomes of Darrach and Sauvé-Kapandji procedures: a systematic review. Hand (N Y). 2022;19(1):68-73.
  4. Shi H, Huang Y, Shen Y, Wu K, Zhang Z, Li Q. Arthroscopic wafer procedure versus ulnar shortening osteotomy for ulnar impaction syndrome: a systematic review and meta-analysis. J Orthop Surg Res. 2024;19(1).
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

  • Salvage of failed distal radioulnar joint reconstruction requires a thorough understanding of normal anatomy, biomechanics, and the modes of failure of the primary procedure to develop effective strategies [1].
  • Most ulnar-sided wrist problems associated with distal radial fractures can be treated non-operatively initially, typically for over a year, in anticipation of substantial improvement with time [2].
  • Distal radioulnar joint instability is often an underestimated lesion requiring systematic clinical examination and imaging for detection [4].
  • Surgeons recommended distal radioulnar joint treatment in 67% (404 of 607) of the scenarios, most commonly cast immobilization in 41% (247 of 607) [5].
  • The management of distal radioulnar joint instability includes treatment strategies such as percutaneous, arthroscopic, soft-tissue, osteotomy and arthroplasty techniques [6].
  • Ulnar shortening osteotomy is a good option to treat patients with ulnar impaction syndrome regardless of the distal radioulnar joint angle [7].
  • Severely damaged and painful distal radioulnar joints can be reconstructed by resection arthroplasty or by hemi- or total arthroplasty [8].
  • DRUJ ligament reconstruction is indicated when native ligaments are not reparable, provided there is no radius or ulna bony deformity or arthritis of the DRUJ [9].
  • The introduction of ulnar head and total radio-ulnar joint prostheses has provided a new method, but there is presently no evidence that these implants produce long-lasting results [10].
  • When appropriate patient selection criteria are met, partial and total ulnar head replacement typically produce reliable results [39].

Anatomy & Pathophysiology

Bony Anatomy and Kinematics

  • The distal radioulnar joint (DRUJ) is a complex anatomic unit providing an articular link between the distal radius and ulna [11].
  • The DRUJ is composed of both bony and soft tissue structures that, along with the proximal radioulnar joint, allow for rotation (pronation/supination) of the forearm [11].
  • Articular surface contact in the shallow sigmoid notch accounts for about 20% of DRUJ stability [46].
  • The sigmoid notch allows dorsopalmar translation of about 1 cm with the forearm in neutral position [46].
  • During forearm rotation, the ulnar head at its articulation with the sigmoid notch moves from dorsal and distal in full pronation to proximal and palmar in full supination [46].
  • The ulnar styloid extends 2 to 6 mm distal to the ulnar head [46].
  • Anatomical variations in the sigmoid notch and ulnar head significantly influence joint mechanics and treatment outcomes [56].
  • The DRUJ kinematics during handstanding vary with school age in female gymnasts, with high school students showing a significantly larger increase in DRUJ separation compared to elementary school students [51].
  • The Aptis distal radioulnar joint arthroplasty considerably alters forearm kinematics [45].

Soft Tissue Anatomy and Stability

  • The triangular fibrocartilage complex (TFCC) includes the dorsal and volar radioulnar ligaments, ulnar collateral ligament, meniscal homologue, articular disc, ulnolunate ligaments, ulnotriquetral ligaments, and extensor carpi ulnaris sheath [46].
  • The deep fibers of the TFCC attach ulnarly at the head of the ulna called the “fovea,” and the superficial fibers attach to the ulnar styloid tip where it joins with the ulnar collateral ligaments [46].
  • Most of the distal radioulnar ligaments and the ulnocapitate ligament attach to the fovea at the base of the ulnar styloid [46].
  • The articular disc has attachments to the distal radioulnar ligaments and passes from the distal margin of the sigmoid notch to the fovea at the base of the ulnar styloid [46].
  • The thickness of the articular disc has an inverse relationship to the amount of ulnar variance [46].
  • The DRUJ functions as a structure of tensegrity where ligament bundles shift tension based on forearm rotation [54].
  • The flexor carpi ulnaris and extensor carpi ulnaris muscles serve as dynamic stabilizers of the distal radioulnar joint [29].
  • The interaction between ligaments, muscles, and bones is emphasized for DRUJ stability [31].

Biomechanics and Load Distribution

  • Loads applied to the distal radiocarpal and ulnocarpal joints are distributed about 80% to the distal radius and 20% to the ulna [46].
  • The distal ulna transmits significant loads to the forearm through the triangular fibrocartilage complex [17].
  • A biomechanical analysis showed that increasing ulnar variance by 2.5 mm dramatically increases the load borne by the distal ulna [32].
  • Pressures within the DRUJ change with forearm rotations, with the highest intra-articular pressure recorded in supination under no disruption-no load, no disruption-loaded, and disrupted TFCC conditions [60].
  • Radial lengthening did not demonstrate a benefit in improving DRUJ stability in a triangular fibrocartilage complex injury model [59].

Pathophysiology and Injury Mechanisms

  • Even minor disruptions of the precise anatomic relationships between the distal radius and ulna and ulnar carpus result in pain syndromes [17].
  • The DRUJ can be dislocated by a variety of mechanisms, including low- and high-energy trauma [17].
  • Dislocations are associated with disruption of the ulnar soft-tissue triangular fibrocartilage complex, including the articular disk and associated ligaments [17].
  • A displaced fracture at the ulnar styloid base indicates a high risk of distal radioulnar instability [17].
  • Injuries to the distal radioulnar joint are common in distal radius fractures [11].
  • Failure to recognize and appropriately treat concomitant DRUJ injuries in distal radius fractures can lead to residual wrist disability and has been associated with worse functional outcomes [11].
  • Alterations in DRUJ biomechanics due to injury can lead to instability and incongruency, which can cause ulnar-sided wrist pain, limitations in range of motion, and the development of further pathology [11].
  • Rupture of the distal radioulnar ligaments usually causes diastasis of the distal radioulnar joint, which can be seen on radiographs and is a pathognomonic sign that the ligaments have been ruptured [18].
  • In most patients with irreducible dislocations of the distal radioulnar joint, the extensor carpi ulnaris was entrapped in the joint and prevented closed reduction [18].
  • Positive ulnar variance or protrusion of the ulna distal to its normal articulation with the ulnar notch of the radius and consequent impingement on the carpus can be caused by malunited Colles fracture, malunion or nonunion of the radius, and cessation or abnormality of growth of the distal radius [32].
  • Significant extraarticular deformities of the distal radius adversely affect distal radioulnar joint function [32].
  • Only 6 mm of radial shortening has been shown to cause distal radioulnar joint dysfunction [32].
  • Decreased radial inclination and dorsal tilt led to moderate changes in joint kinematics, while dorsal displacement caused minimal changes [32].
  • Radioulnar arthrosis has been found to be more common than radiocarpal arthrosis [32].
  • Approximately 70% of the patients who developed radioulnar arthrosis require surgical intervention [32].
  • Deterioration of the distal radioulnar joint is believed to be caused by shortening and angular deformities of the distal radius [32].

Classification

TFCC Tear Classification (Palmer)

  • The Palmer classification categorizes triangular fibrocartilage complex (TFCC) tears into traumatic (Class 1) and degenerative (Class 2) types [27, 28].
  • TFCC tear subtypes are defined based on the specific location within the TFCC [27, 28].
  • The class and location of a TFCC tear have important implications for treatment [27, 28].
  • Class 1 (Traumatic) TFCC injuries are subdivided into four types according to the tear's location [58].
  • Type 1-B injuries are peripheral tears located at the ulnar end of the TFCC [58].
  • Class 1A TFCC injuries are characterized by central perforation or tear [27, 28].
  • Class 1B TFCC injuries are characterized by ulnar avulsion with or without ulnar styloid fracture [27, 28].
  • Class 1C TFCC injuries are characterized by distal avulsion involving the origins of the ulnolunate and ulnotriquetral ligaments [27, 28].
  • Class 1D TFCC injuries are characterized by radial avulsion involving the dorsal and/or volar radioulnar ligaments [27, 28].
  • Class 2 (Degenerative) TFCC tears are associated with ulnocarpal impaction syndrome [27, 28].
  • Class 2A TFCC tears are characterized by TFCC wear or thinning [27, 28].
  • Class 2B TFCC tears are characterized by TFCC wear plus lunate and/or ulnar chondromalacia [27, 28].
  • Class 2C TFCC tears are characterized by TFCC perforation plus lunate and/or ulnar chondromalacia [27, 28].
  • Class 2D TFCC tears are characterized by TFCC perforation, lunate and/or ulnar chondromalacia, and lunotriquetral ligament disruption [27, 28].
  • Class 2E TFCC tears are characterized by TFCC perforation, lunate and/or ulnar chondromalacia, lunotriquetral ligament disruption, and ulnocarpal and DRUJ arthritis [27, 28].

Arthroscopic Treatment-Oriented Classification

  • Advances in diagnostic arthroscopy permit a treatment-oriented classification of TFCC peripheral tears into five categories: repairable distal tears, repairable complete tears, repairable proximal tears, non-repairable tears, and tears associated with DRUJ arthritis [58].
  • In the arthroscopic treatment-oriented classification, Class 1 tears should be sutured [58].
  • In the arthroscopic treatment-oriented classification, Class 2 and 3 tears are associated with DRUJ instability and require TFCC reattachment to the fovea [58].
  • In the arthroscopic treatment-oriented classification, Class 4 tears need reconstruction using a tendon graft [58].
  • In the arthroscopic treatment-oriented classification, Class 5 tears require an arthroplasty [58].

DRUJ Instability and Pathology

  • The management of distal radioulnar joint instability includes categorization of instability and treatment strategies such as percutaneous, arthroscopic, soft-tissue, osteotomy, and arthroplasty techniques [6].
  • Arthrosis of the distal radioulnar joint can result from inflammatory arthropathy, traumatic disruption of articular surfaces, traumatic disruption of soft tissue constraints leading to instability, infection, or developmental malformation [36].

Clinical Presentation

General Presentation and Diagnosis

  • Failure to recognize and appropriately treat concomitant distal radioulnar joint injuries in the setting of distal radius fractures can lead to residual wrist disability and is associated with worse functional outcomes [11].
  • Chronic distal radioulnar joint instability results from various traumatic injuries and can lead to chronic functional impairment, pain, and arthritis if left untreated [12].
  • There should be a high index of suspicion to diagnose distal radioulnar joint dislocation because radiographs not taken in the perfect lateral orientation tend to look relatively normal [17].
  • In the presence of forearm and elbow fracture-dislocations, further evaluation of the radioulnar joint is mandatory [17].
  • Dysfunction of the distal radioulnar joint is a frequent source of persistent complaints after distal radial malunions [32].
  • Characteristic symptoms of distal radioulnar joint dysfunction after distal radial malunions include pain, decreased forearm rotation, decreased grip strength, and instability [32].
  • Approximately 70% of patients who developed radioulnar arthrosis require surgical intervention [32].
  • The occurrence of osteoarthritis of the distal radioulnar joint was affected by the presence of osteoarthritis of the adjacent joint [24].

Physical Examination

  • The clinical examination is key, with identification of the distal radioulnar joint surface anatomy and clinical evaluation of the joint [17].
  • The amount of stability should be carefully assessed and compared with that of the opposite wrist [17].
  • The patient should position the wrist to reproduce the pain [17].
  • With the hand pronated, the examiner tries to displace the ulnar head by applying a dorsal to volar load 4 cm proximal to the distal radioulnar joint, known as the "piano key test" [17].
  • Little resistance to ballottement and volar movement of the ulna head corresponds to a positive piano key test [17].
  • Subluxation is much more common than anterior or posterior dislocation [17].
  • Limitation of pronation and supination, or pain associated with such motion, would be expected in the situation of subluxation [17].
  • Palpation of the sixth extensor compartment during resisted pronation is useful to identify any subluxation [17].
  • The reliability of clinical assessment of distal radioulnar joint instability has been questioned [50].
  • A recent publication has shown distal radioulnar joint instability to be more common than previously appreciated [50].
  • After a distal radial fracture, a degree of distal radioulnar joint instability is universally present when measured quantitatively [50].
  • The figure for quantitative instability after distal radial fracture is far greater than the range of 0–35% previously reported in the literature when clinical assessment is the sole determinant of stability [50].
  • Surgeons working in the United Kingdom were unreliable in assessing distal radioulnar joint instability [50].
  • The sensitivity of clinical assessment of distal radioulnar joint instability in wrists previously measured on a validated jig was 24% [50].
  • The specificity of clinical assessment of distal radioulnar joint instability in wrists previously measured on a validated jig was 94% [50].

Imaging and Diagnostic Modalities

  • Distal radioulnar joint instability requires systematic clinical examination and imaging for detection [4].
  • There is substantial surgeon-to-surgeon variation in interpreting MRI signal changes and arthroscopic findings in the distal radioulnar ligaments and central disc [35].
  • Variation in interpreting MRI signal changes and arthroscopic findings raises concerns about overdiagnosis and overtreatment versus underdiagnosis [35].

Investigations

Clinical Examination

  • Distal radioulnar joint instability is often an underestimated lesion requiring systematic clinical examination for detection [4].
  • A thorough knowledge of the anatomy and kinematics of the distal radioulnar joint is necessary to manage pathologic conditions [3].

Imaging

  • Standard well-positioned radiography is the appropriate first step for imaging the distal radioulnar joint [63].
  • High-resolution MRI helps delineate ligamentous structures of the distal radioulnar joint [63].
  • Dynamic CT is indicated for clinical instability of the distal radioulnar joint [63].
  • Imaging the distal radioulnar joint requires knowledge of the complex bony, muscular, and ligamentous anatomy [63].
  • MRI is controversial but newer innovations suggest value in detection and localization of triangular fibrocartilage complex pathology [27].
  • Arthroscopy is the gold standard for detection of triangular fibrocartilage complex tears [27].
  • The arthroscopic trampoline test is performed to assess triangular fibrocartilage complex resiliency by balloting the central portion with a small probe [27].
  • The arthroscopic hook test can be used to demonstrate peripheral detachment of the triangular fibrocartilage complex [27].
  • The arthroscopic suction test can show laxity of the triangular fibrocartilage complex when peripherally scarred in or foveal detachment when the distal radioulnar joint is clinically unstable [27].
  • A nuanced understanding of three-dimensional relationships between ulnar bowing and distal radioulnar joint anatomy can enhance preoperative planning when correcting ulnar-side pathology [62].

Diagnostic Considerations

Treatment

Non-Operative

  • Dorsal dislocation or subluxation of the distal radioulnar joint should be treated by reduction of the ulnar head into the sigmoid fossa and placement of the forearm in full supination [17].
  • The arm should be immobilized in supination, which requires a long arm cast or splint [17].
  • Volar dislocation is relatively rare and is usually stable after reduction [17].
  • If dorsal or volar dislocation or subluxation of the distal ulna cannot be reduced with manipulation in the outpatient setting, closed treatment can be attempted under anesthesia [17].
  • An excellent result can usually be expected if a distal radioulnar joint dislocation is reduced early and immobilized for 1 month in plaster [18].

Operative

  • If closed reduction of a distal radioulnar joint dislocation fails, open reduction and soft-tissue reconstruction may be necessary [17].
  • A retinacular flap may be used to transpose the extensor carpi ulnaris to a more dorsal position to stabilize the distal ulna [17].
  • If a distal radioulnar joint dislocation is less than 2 months old and cannot be reduced closed, open reduction with exposure and repair of the triangular fibrocartilage is advised [18].
  • If a distal radioulnar joint dislocation is reduced surgically after more than 2 months, consideration should be given to excision of the distal ulna and distal ligament reconstruction [18].
  • Rupture of the distal radioulnar ligaments usually causes diastasis of the distal radioulnar joint, which is a pathognomonic sign that the ligaments have been ruptured and should be repaired [18].
  • A dorsal approach was used to free the extensor carpi ulnaris, and repair of the triangular fibrocartilage or transosseous pinning was used to stabilize the joint in irreducible dislocations [18].
  • Operations to reconstruct permanently damaged ligaments of the distal radioulnar joint cannot be successful unless the component bones are undeformed [18].
  • Indirect ulnar shortening by distraction through the distal radius fracture site provides a simple and novel strategy for the management of persistent DRUJ instability during volar plating, obviating the need for prolonged immobilization or to alter standard postoperative protocols [40].
  • Advances in minimally invasive surgical techniques have transformed the management of DRUJ instability [41].
  • The combined HS and suture repair effectively restores stability to both the DRUJ and UCJ in patients with TFCC-related ulnocarpal instability, considerably reducing pain and preserving range of motion [61].
  • The Aptis total distal radioulnar joint prosthesis is a good rescue option for patients with previous failed surgical procedures, providing significant improvements in range of motion, grip strength, and pain scores with a mean follow-up of 9.7 years [42].
  • Surgical outcomes are best when performed before the patient displays severe joint destruction, fixed contractures, subluxation, or dislocation [19].
  • Stabilization of the ulnar stump seems to alleviate pain and improve forearm rotation and functional outcomes, although no direct correlation exists between radioulnar convergence and patient outcomes [21].
  • Approximately 2 cm of bone is resected during distal ulna excision [34].
  • If excessive bone is removed during distal ulna excision, distal ulna stability may pose a problem [34].
  • The dorsal edge of the proximal ulna should be made bevel and smooth to minimize the risk of postoperative attrition ruptures of the extensor tendons [34].
  • Reconstruction of the soft tissue support for both the DRUJ and radiocarpal joint is important to correct carpal supination and stabilize the distal ulna after distal ulna excision [34].
  • If the TFCC and radioulnar ligamentous complex are present, they are sutured tightly to the dorsal and ulnar aspect of the radius during distal ulna excision [34].
  • A distally based strip of the ECU tendon can be detached, woven through the ulnar collateral ligament and any remnants of the triangular fibrocartilage, and sutured to the radius to stabilize the distal ulna [34].
  • A distally based slip of the ECU tendon can be passed through the distal end of the ulna through a hole made in the dorsal cortex of the ulna and then sutured back onto itself to stabilize the distal ulna [34].
  • The ulna can be compressed volarward using a Freer elevator and either the capsular tissue or ECU tendon sutured tightly to seat the ulna stump in this volar position to stabilize the ulna stump [34].
  • Treatment goals in the acute setting should be to prevent future instability or incongruency of the distal radioulnar joint [11].
  • Treatment goals in the chronic setting should be to restore stability and congruency of the distal radioulnar joint to allow for painless, full (or improved) motion of the wrist and forearm [11].
  • Treatment in the chronic setting can be challenging [11].
  • Hand therapy is essential after arthroplasty around the wrist [55].
  • Pain-free functional motion with adequate strength is the main goal of all joint reconstructions [55].
  • Loosening of the prosthesis is a leading cause of poor outcome in arthroplasty [55].
  • To protect the prosthesis, patients are discouraged from lifting more than 2 lb regularly and no more than 10 lb [55].

Complications

Post-traumatic Instability and Natural History

  • The presence of untreated triangular fibrocartilage complex (TFCC) tears has been found to correlate with objective and subjective distal radioulnar joint instability at 1 year [57].
  • A prospective longitudinal study found that 45% of patients with distal radial fractures and untreated complete TFCC injuries had laxity of the distal radioulnar joint at 13–15 years [57].
  • Patients with distal radioulnar joint laxity after distal radial fractures had worse grip strength and trends of worse Gartland and Werley and QuickDASH scores compared to patients with stable distal radioulnar joints, although this difference did not reach statistical significance [57].
  • There is evidence that all patients with distal radial fractures have measurable distal radioulnar joint instability [57].
  • There is evidence supporting gradual improvement of ulnar-sided wrist symptoms up to 1 year after distal radial fracture treatment [57].
  • Persistent significant instability of the distal radioulnar joint in patients with distal radial fractures is not seen in large numbers at follow-up [57].
  • A minority of patients presenting with primary TFCC rupture after distal radial fracture treatment experience long-term invalidating complaints due to instability of the distal radioulnar joint [57].
  • Less than 4% of patients treated for distal radial fractures had further surgery for persistent symptomatic distal radioulnar joint instability in one institution's experience [57].
  • The natural history of patients with distal radioulnar joint instability after distal radial fracture treatment seems fairly benign, although this is not supported by robust evidence in the literature [57].
  • The majority of patients with distal radioulnar joint instability after distal radial fracture treatment improve with time, have good function, and do not require further procedures [57].

Complications of Immobilization and Surgical Technique

  • Prolonged immobilization in supination leads to stiffness [57].
  • Indirect ulnar shortening by distraction through the distal radius fracture site provides a strategy for the management of persistent distal radioulnar joint instability during volar plating, obviating the need for prolonged immobilization or to alter standard postoperative protocols [40].

Complications of Salvage and Arthroplasty Procedures

  • The introduction of ulnar head and total radio-ulnar joint prostheses has provided a new method for failed ulnar head resection, but there is presently no evidence that these implants produce long-lasting results [10].
  • Both APTIS distal radioulnar joint arthroplasty and ulnar head replacement yield substantial functional improvements and good long-term survivorship [43].
  • Adding a distally based longitudinal extensor carpi ulnaris strip to ulnar shortening osteotomy for restoring distal radioulnar joint stability seems to be an effective treatment in patients with irreparable degenerative triangular fibrocartilage complex injuries due to ulnar impaction syndrome [44].

Degenerative and Associated Conditions

Recovery

  • Chronic distal radioulnar joint instability can lead to chronic functional impairment, pain, and arthritis if left untreated [12].
  • Stabilization of the ulnar stump seems to alleviate pain and improve forearm rotation and functional outcomes [21].
  • No direct correlation exists between radioulnar convergence and patient outcomes [21].

Key Evidence

  • [L5] Salvage of failed distal radioulnar joint reconstruction requires a thorough understanding of normal anatomy, biomechanics, and the modes of failure of the primary procedure to develop effective strategies. [1] (10.1016/j.hcl.2010.05.004)
  • [L5] Most ulnar-sided wrist problems associated with distal radial fractures can be treated non-operatively initially, typically for over a year, in anticipation of substantial improvement with time. [2] (10.1177/17531934221140238)
  • [L5] A thorough knowledge of the anatomy and kinematics of the distal radioulnar joint is necessary to manage pathologic conditions. [3] (10.1016/j.hcl.2005.08.002)
  • [L5] Distal radioulnar joint instability is often an underestimated lesion requiring systematic clinical examination and imaging for detection. [4] (10.1007/s00402-020-03371-0)
  • [L4] Surgeons recommended distal radioulnar joint treatment in 67% (404 of 607) of the scenarios, most commonly cast immobilization in 41% (247 of 607). [5] (10.1177/17531934261449057)
  • [L5] The purpose of this article is to review distal radioulnar joint instability and its management, covering anatomic and biomechanical advances, categorization of instability, and treatment strategies including percutaneous, arthroscopic, soft-tissue, osteotomy and arthroplasty techniques. [6] (10.1177/1753193414527052)
  • [L4] Ulnar shortening osteotomy is a good option to treat patients with ulnar impaction syndrome regardless of the distal radioulnar joint angle. [7] (10.1177/17531934241262931)
  • [L5] Severely damaged and painful distal radioulnar joints can be reconstructed by resection arthroplasty or by hemi- or total arthroplasty. [8] (10.1016/j.hcl.2020.07.008)
  • [L5] DRUJ ligament reconstruction is indicated when native ligaments are not reparable, provided there is no radius or ulna bony deformity or arthritis of the DRUJ. [9] (10.1016/j.hcl.2020.07.004)
  • [L5] The introduction of ulnar head and total radio-ulnar joint prostheses has provided a new method, but there is presently no evidence that these implants produce long-lasting results. [10] (10.1054/jhsb.2002.0815)
  • [L5] [11] (10.1016/j.hcl.2021.02.011)
  • [L5] Chronic distal radioulnar joint instability results from various traumatic injuries and can lead to chronic functional impairment, pain, and arthritis if left untreated. [12] (10.1016/j.hcl.2010.05.010)
  • [L5] Surgical outcomes are best when performed before the patient displays severe joint destruction, fixed contractures, subluxation, or dislocation. [19] (10.1016/j.hcl.2005.08.009)
  • [L5] Stabilization of the ulnar stump seems to alleviate pain and improve forearm rotation and functional outcomes, although no direct correlation exists between radioulnar convergence and patient outcomes. [21] (10.1016/j.hcl.2014.12.003)
  • [L4] The occurrence of osteoarthritis of the scaphotrapeziotrapezoid and distal radioulnar joints was affected by the presence of osteoarthritis of the adjacent joint. [24] (10.1016/j.jhsa.2023.05.009)
  • [L4] The flexor carpi ulnaris and extensor carpi ulnaris muscles serve as dynamic stabilizers of the distal radioulnar joint. [29] (10.1177/17531934231168299)
  • [L5] The purpose of this review article is to present and illustrate the current understanding of the functional anatomy and pathomechanics of the distal radioulnar joint, emphasizing the interaction between ligaments, muscles, and bones for stability. [31] (10.1177/1753193417693170)
  • [L5] There is substantial surgeon-to-surgeon variation in interpreting MRI signal changes and arthroscopic findings in the distal radioulnar ligaments and central disc, raising concerns about overdiagnosis and overtreatment versus underdiagnosis. [35] (10.1177/17531934241254705)
  • [Paper] [36] (10.1016/j.hcl.2005.08.015)
  • [L4] When appropriate patient selection criteria are met, partial and total ulnar head replacement typically produce reliable results. [39] (10.1177/1753193417693177)
  • [L4] Indirect ulnar shortening by distraction through the distal radius fracture site provides a simple and novel strategy for the management of persistent DRUJ instability during volar plating, obviating the need for prolonged immobilization or to alter standard postoperative protocols. [40] (10.1016/j.jhsa.2018.02.030)
  • [L5] Advances in minimally invasive surgical techniques have transformed the management of DRUJ instability. [41] (10.1177/17531934261417561)
  • [L4] The Aptis total distal radioulnar joint prosthesis is a good rescue option for patients with previous failed surgical procedures, providing significant improvements in range of motion, grip strength, and pain scores with a mean follow-up of 9.7 years. [42] (10.1177/17531934231192375)
  • [L2] Both APTIS DRUJ arthroplasty and ulnar head replacement yield substantial functional improvements and good long-term survivorship. [43] (10.1177/17531934261415827)
  • [L4] Adding a distally based longitudinal extensor carpi ulnaris strip to ulnar shortening osteotomy for restoring distal radioulnar joint stability seems to be an effective treatment in patients with irreparable degenerative triangular fibrocartilage complex injuries due to ulnar impaction syndrome. [44] (10.1177/17531934231197942)
  • [L4] The Aptis distal radioulnar joint arthroplasty considerably alters forearm kinematics, which can have clinical implications. [45] (10.1177/17531934241274142)
  • [L5] [50] (10.1177/17531934241275456)
  • [L4] The DRUJ kinematics during handstanding vary with school age in female gymnasts, with high school students showing a significantly larger increase in DRUJ separation compared to elementary school students. [51] (10.1177/23259671251368997)
  • [L5] The joint functions as a structure of tensegrity where ligament bundles shift tension based on forearm rotation. [54] (10.1016/j.hcl.2010.05.002)
  • [L5] [55] (10.1016/j.hcl.2012.08.025)
  • [L5] Anatomical variations in the sigmoid notch and ulnar head significantly influence joint mechanics and treatment outcomes. [56] (10.1016/j.hcl.2012.03.002)
  • [L5] [57] (10.1177/17531934241268980)
  • [L5] [58] (10.1177/1753193409100120)
  • [L5] Radial lengthening did not demonstrate a benefit in improving DRUJ stability in a triangular fibrocartilage complex injury model. [59] (10.1016/j.jhsa.2025.06.013)
  • [L5] Pressures within the DRUJ changed with forearm rotations, with the highest intra-articular pressure recorded in supination under no disruption-no load, no disruption-loaded, and disrupted TFCC conditions. [60] (10.1016/j.jhsa.2023.11.015)
  • [L4] The combined HS and suture repair effectively restores stability to both the DRUJ and UCJ in patients with TFCC-related ulnocarpal instability, considerably reducing pain and preserving range of motion. [61] (10.1016/j.jhsg.2025.100806)
  • [L4] A nuanced understanding of these 3D relationships can enhance preoperative planning when correcting ulnar-side pathology. [62] (10.1016/j.jhsg.2023.12.006)
  • [L5] Imaging the DRUJ requires knowledge of the complex bony, muscular, and ligamentous anatomy; standard well-positioned radiography is the appropriate first step, while high-resolution MRI helps delineate ligamentous structures and dynamic CT is indicated for clinical instability. [63] (10.1016/j.hcl.2010.07.001)

References

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[2] The distal radioulnar joint after distal radial fractures: when and how do we need to treat pain, stiffness or instability?. Journal of Hand Surgery (European Volume). 2023. DOI: 10.1177/17531934221140238

[3] Hemiresection Arthroplasty of the Distal Radioulnar Joint. Hand Clinics. 2005. DOI: 10.1016/j.hcl.2005.08.002

[4] Distal radioulnar joint instability: current concepts of treatment. Archives of Orthopaedic and Trauma Surgery. 2020. DOI: 10.1007/s00402-020-03371-0

[5] Factors associated with variation in treatment of the distal radioulnar joint after plate fixation of distal radial fractures. Journal of Hand Surgery (European Volume). 2026. DOI: 10.1177/17531934261449057

[6] Instability of the distal radioulnar joint. Journal of Hand Surgery (European Volume). 2014. DOI: 10.1177/1753193414527052

[7] Does the distal radioulnar joint orientation influence the outcome of ulnar shortening osteotomy: a retrospective study. Journal of Hand Surgery (European Volume). 2024. DOI: 10.1177/17531934241262931

[8] Solutions for the Unstable and Arthritic Distal Radioulnar Joint. Hand Clinics. 2020. DOI: 10.1016/j.hcl.2020.07.008

[9] Chronic Distal Radioulnar Joint Instability. Hand Clinics. 2020. DOI: 10.1016/j.hcl.2020.07.004

[10] Failed Ulnar Head Resection: Prevention and Treatment. Journal of Hand Surgery. 2002. DOI: 10.1054/jhsb.2002.0815

[11] Distal Radius Fracture and the Distal Radioulnar Joint. Hand Clinics. 2021. DOI: 10.1016/j.hcl.2021.02.011

[12] The Management of Chronic Distal Radioulnar Instability. Hand Clinics. 2010. DOI: 10.1016/j.hcl.2010.05.010

[17] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 2Musculoskeletal Trauma Surgery > 2. Distal Radioulnar Joint Dislocation (ICD-9:833.01).

[18] Campbell S Operative Orthopaedics 4 Volume Set. OPEN REDUCTION AND REPAIR OF PATELLAR DISLOCATION > DISTAL RADIOULNAR JOINT.

[19] Management of the Distal Radioulnar Joint in Rheumatoid Arthritis. Hand Clinics. 2005. DOI: 10.1016/j.hcl.2005.08.009

[21] Management of Complications of Distal Radioulnar Joint. Hand Clinics. 2015. DOI: 10.1016/j.hcl.2014.12.003

[24] Prevalence and Associated Factors for Primary Osteoarthritis of the Scaphotrapeziotrapezoid, Radiocarpal, and Distal Radioulnar Joints in the Japanese General Elderly Population. The Journal of Hand Surgery. 2025. DOI: 10.1016/j.jhsa.2023.05.009

[27] Miller S Review Of Orthopaedics. DISTAL RADIOULNAR JOINT, TRIANGULAR FIBROCARTILAGE COMPLEX, AND WRIST ARTHROSCOPY > 2. TFCC tears.

[28] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > DISTAL RADIOULNAR JOINT, TRIANGULAR FIBROCARTILAGE COMPLEX, AND WRIST ARTHROSCOPY > 2. TFCC tears.

[29] Stability of the distal radioulnar joint with and without activation of forearm muscles. Journal of Hand Surgery (European Volume). 2023. DOI: 10.1177/17531934231168299

[31] Distal radioulnar joint: functional anatomy, including pathomechanics. Journal of Hand Surgery (European Volume). 2017. DOI: 10.1177/1753193417693170

[32] Campbell S Operative Orthopaedics 4 Volume Set. RESECTION OF PROXIMAL PART OF RADIAL SHAFT > DISTAL RADIOULNAR JOINT INCONGRUITY AND ARTHROSIS.

[34] Green S Operative Hand Surgery. Distal Radioulnar Joint in Rheumatoid Arthritis.

[35] Pain and instability ascribed to the distal radioulnar ligaments and central disc as part of the triangular fibrocartilage complex: a round table discussion. Journal of Hand Surgery (European Volume). 2024. DOI: 10.1177/17531934241254705

[36] Use of an Ulnar Head Endoprosthesis for Treatment of an Unstable Distal Ulnar Resection: Review of Mechanics, Indications, and Surgical Technique. Hand Clinics. 2005. DOI: 10.1016/j.hcl.2005.08.015

[39] Non-constrained implant arthroplasty for the distal radioulnar joint. Journal of Hand Surgery (European Volume). 2017. DOI: 10.1177/1753193417693177

[40] Radial Distraction to Stabilize Distal Radioulnar Joint in Distal Radius Fixation. The Journal of Hand Surgery. 2018. DOI: 10.1016/j.jhsa.2018.02.030

[41] Restoring balance in the distal radioulnar joint: advancements in minimally invasive surgical approaches. Journal of Hand Surgery (European Volume). 2026. DOI: 10.1177/17531934261417561

[42] Long-term results of the AptisTM total distal radioulnar joint prosthesis after previous failed surgical procedures. Journal of Hand Surgery (European Volume). 2023. DOI: 10.1177/17531934231192375

[43] Efficacy and safety of prosthetic arthroplasty of the distal radioulnar joint: a systematic review. Journal of Hand Surgery (European Volume). 2026. DOI: 10.1177/17531934261415827

[44] An alternative treatment for degenerative triangular fibrocartilage complex injuries with distal radioulnar joint instability: first experience with 48 patients. Journal of Hand Surgery (European Volume). 2023. DOI: 10.1177/17531934231197942

[45] Performance of the Aptis distal radioulnar joint implant: kinematic and geometric analysis. Journal of Hand Surgery (European Volume). 2024. DOI: 10.1177/17531934241274142

[46] Campbell S Operative Orthopaedics 4 Volume Set. MALPOSITIONED NONUNION OF SCAPHOID FRACTURES ("HUMPBACK" DEFORMITY) > DISTAL RADIOULNAR AND ULNOCARPAL JOINT INJURIES.

[50] The reliability of clinical assessment of distal radioulnar joint instability among non-United Kingdom European surgeons. Journal of Hand Surgery (European Volume). 2024. DOI: 10.1177/17531934241275456

[51] Distal Radioulnar Joint Kinematics Evaluated Using Ultrasonography During Handstanding in Female Gymnasts. Orthopaedic Journal of Sports Medicine. 2025. DOI: 10.1177/23259671251368997

[54] Understanding Stability of the Distal Radioulnar Joint Through an Understanding of Its Anatomy. Hand Clinics. 2010. DOI: 10.1016/j.hcl.2010.05.002

[55] Rehabilitation Following Thumb CMC, Radiocarpal, and DRUJ Arthroplasty. Hand Clinics. 2013. DOI: 10.1016/j.hcl.2012.08.025

[56] Anatomy and Biomechanics of the Distal Radioulnar Joint. Hand Clinics. 2012. DOI: 10.1016/j.hcl.2012.03.002

[57] Round table discussion. Distal radioulnar joint instability after surgical treatment of distal radial fractures. Journal of Hand Surgery (European Volume). 2024. DOI: 10.1177/17531934241268980

[58] New trends in arthroscopic management of type 1-B TFCC injuries with DRUJ instability. Journal of Hand Surgery (European Volume). 2009. DOI: 10.1177/1753193409100120

[59] Effect of Radial Lengthening on the Stability of the Distal Radioulnar Joint: A Biomechanical Cadaveric Study. The Journal of Hand Surgery. 2026. DOI: 10.1016/j.jhsa.2025.06.013

[60] Intra-Articular Pressure in the Distal Radioulnar Joint: A Biomechanical Study. The Journal of Hand Surgery. 2025. DOI: 10.1016/j.jhsa.2023.11.015

[61] Extensor Retinaculum Capsulorrhaphy and Suture Repair for Ulnocarpal and Distal Radioulnar Joint Instability: One-Year Results. Journal of Hand Surgery Global Online. 2025. DOI: 10.1016/j.jhsg.2025.100806

[62] Ulnar Bowing and Distal Radioulnar Joint Anatomy: A Three-Dimensional, In Situ Clinical Assessment. Journal of Hand Surgery Global Online. 2024. DOI: 10.1016/j.jhsg.2023.12.006

[63] Imaging the Distal Radioulnar Joint. Hand Clinics. 2010. DOI: 10.1016/j.hcl.2010.07.001

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b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.

Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.