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远端桡尺关节手术

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Updated Sep 2026
Illustration: 远端桡尺关节手术

本页面由机器翻译，尚未经临床医生审核。英文版本为权威版本。

为何建议进行此手术

Mater Private Hospital Rockhampton 的上肢外科医生 Kieran Hirpara 医生会从适合您病情的微创方案开始。患者通常由其全科医生（GP）转诊至我们的诊所；如果理疗师建议您就诊，您仍需获得全科医生的转诊，方有资格享受 Medicare 报销。在您的预约就诊时，我们会采集病史，检查您的手腕，并在必要时安排影像学检查，以查明导致您疼痛的原因。

远端桡尺关节是前臂两根骨头之间的关节，位于手腕正上方。当该关节出现磨损、不稳定或受伤后受损，并导致手腕小指侧疼痛、前臂旋转困难或握力减弱时，会建议进行手术。对于长期存在的问题，我们通常首先尝试非手术治疗：活动调整、物理治疗或手部治疗，以及支具固定。当这些措施未能带来足够改善时，才会考虑手术。有些该关节的损伤从一开始就不稳定，对于这些情况，我们可能会直接建议手术。手术的目的是缓解您的疼痛，让您能够更舒适、更自信地旋转前臂并使用手部。

手术前

一旦您的手术预约成功，我们将为您提供明确的准备指导。您需要在手术前七小时停止进食和饮水。我们要求七小时而非更短的时间，以便如果当天手术进度提前，您的手术顺序可以提前。如果您正在服用常规药物，请携带一份书面药物清单到医院，我们将告知您哪些药物需要暂停以及何时暂停。大多数人术前不需要额外的检查。如果您有其他健康状况，可能需要进行血液检查或与麻醉师（负责为您实施麻醉的医生）进行会诊。请安排他人在术后驾驶送您回家，并在手术当天穿着宽松、舒适的衣物。

手术当天

手术当天，您需前往医院的手术入院单元。在那里，您将被办理入院手续并做术前准备。您将会见麻醉科医生，即负责管理您麻醉事宜的医生。本手术在全身麻醉下进行。有时会追加区域神经阻滞以缓解术后疼痛；麻醉科医生将在当天就此与您讨论。

随后，您将被带入手术室进行手术。术后，您将在复苏区苏醒，护士会在麻醉消退期间看护您。待您的生命体征平稳后，根据手术类型及恢复情况，您将被转入病房或直接回家。

手术内容

针对该关节的手术方式不止一种，最适合您的方案取决于关节的具体病变情况。如果腕部骨折后关节脱位，外科医生会将骨骼复位至正确位置，并在愈合期间将其固定，有时需使用石膏。如果关节磨损且伴有疼痛，外科医生可能会切除前臂骨（尺骨）在手腕小指侧末端的骨性部分。该操作通过手腕背侧小指侧的切口进行。切除磨损的骨面可防止前臂旋转时两根前臂骨相互摩擦。

如果关节松弛而非磨损，外科医生可以重建维持关节稳定的韧带。韧带是连接骨骼的强韧组织带。该操作利用一段肌腱（连接肌肉与骨骼的组织），将其编织穿过骨骼上的小孔，起到类似新束带的作用以固定关节。此方法仅在关节面本身仍健康时可行。

如果整个关节严重磨损，外科医生可能会进行关节置换。切除前臂骨末端的受损骨骼，并用金属制成的人工关节替代，有时还包括塑料部件，以便两根前臂骨能够再次平滑地相对运动。

手术结束时，外科医生会用缝线关闭切口并覆盖敷料。您醒来时，手和手腕将被绷带包扎，敷料需保留约10天。

术后

苏醒后，您将被安置在恢复区，护士会在麻醉消退期间查看您的情况。您的手和手腕将被包扎，您可能需要使用吊带来固定手臂。我们会为您提供镇痛治疗以确保您的舒适；如果疼痛未得到缓解，请告知护士。一旦您感觉可以活动，即可起身走动，但最初的24小时内应有人陪同。您的医疗团队会告知您是当天出院还是在医院留观一晚。敷料通常保留约10天；除非我们告知您，否则请勿在此之前拆除。我们会在复诊时为您更换或拆除敷料。

恢复

在最初几天，您的手腕会感到疼痛和肿胀，小指侧可能会有搏动性疼痛，尤其是在夜间。将手垫高放在枕头上，即使在睡觉时也是如此，有助于减轻肿胀。我们提供的止痛药在规律服用时效果最佳，而不是等到疼痛加剧时才服用。

您出院时，手臂将用绷带包扎并置于吊带中。敷料需保留约10天，我们将在复诊时为您更换或拆除。术后的康复由Extend Rehabilitation的Ruby Doolan负责。Ruby是一名手部治疗师：她将指导您的锻炼，并为您制作所需的支具。早期，锻炼动作轻柔，重点在于保持手指、肘部和肩部的活动。随着愈合进程，锻炼将侧重于前臂旋转和恢复抓握力。

在日常生活中，起初您需要他人协助完成需要双手配合的任务，如穿衣、烹饪和搬运物品。一旦肿胀消退且活动度恢复，日常活动会变得更容易。当您能够无痛抓握并舒适地旋转前臂时，您会发现手部功能有所改善。如果驾驶是您恢复计划的一部分，在佩戴吊带或支具期间、服用强效止痛药期间，或者除非您能用双手握住方向盘并在紧急制动时做出反应，否则您不得驾驶。请参阅我们的指南上肢手术后驾驶。

每个人的愈合速度各不相同，您的时间表可能有所不同。您的外科医生和手部治疗师将在每个阶段为您提供指导。

可能出现的问题

大多数患者恢复良好，但偶尔会出现问题。您的外科医生和团队会密切监测您，以便尽早发现任何问题。

如果前臂骨远端的一部分已被切除，剩余的骨端有时会移位或压迫邻近结构。当您旋转前臂时，可能会感到手腕小指侧有尖锐或研磨样疼痛，或感觉有东西卡住。请在下次复诊时告知医生。

有些人会注意到术后手腕疼痛减轻但僵硬，向前弯曲的活动度减少。如果前臂旋转感觉受限，您的肩部通常会无意识地代偿，因此日常生活中的差异可能很小。请在复诊时提及任何您不满意的活动受限情况。

如果该关节在手腕骨折的同时受损，关节可能在早期脱位，有时在最初两周内发生。这很容易被忽视。请留意新的疼痛、肿胀或手腕形状的改变，如果您注意到这些情况，请告知诊所。

手腕该侧的软骨垫撕裂若未得到治疗，可能导致关节感觉松动。您可能会注意到手腕负重时有咔哒声、移位或撞击感，或握力减弱。如果关节在其他治疗后仍然松动且疼痛，有时需要进一步手术，但许多人随时间推移会改善，不需要再次手术。尺侧手腕症状在骨折手术后一年内通常会持续改善。

对于自青少年时期就存在的长期手腕畸形，关节可能随时间逐渐磨损或不稳定。在严重情况下，伸直手指的肌腱可能因摩擦突出的骨骼而磨损断裂，导致突然失去伸直一个或多个手指的能力。如果手指无法伸直，请立即联系诊所。

与任何手腕手术一样，骨骼愈合可能缓慢或无法连接，且切除骨骼的区域可能变得不稳定并引起疼痛。手腕背侧的持续性疼痛应在复诊时提出。

本页上的并发症表列出了典型发生率，如果您想了解具体细节，可以参考。

何时联系我们

如果您出现发热，或伤口周围皮肤变得更红、肿胀或渗液，请致电我们。如果您的疼痛突然加剧，或在最初两周内手腕出现新的疼痛或肿胀，请致电我们。如果手指无法伸直，或手腕感觉松动、有弹响或无力，请告知我们。如果您出现小腿肿胀或疼痛、呼吸困难、胸痛、手部麻木，或无法活动手臂或手指，请立即前往急诊。

深入探讨

Advanced reading: the deeper science (optional)

本节内容超出了您自行做出治疗决策所需的深度。远端桡尺关节值得额外阅读，因为它是手腕中我们测量最不准确的关节，也是最常被过早归咎的关节，且等待观察往往是最正确的选择。

我们无法可靠地测量该问题

该关节的不稳定性主要依靠手感进行诊断，检查者将尺骨相对于桡骨进行移位并据此形成判断。2025年一项关于评估策略的综述明确指出，用于分析远端桡尺关节不稳定性的可靠且可量化的方法仍属未满足的需求，而开发此类方法对于改善治疗至关重要 [1]。

这对您有直接的影响。当诊断依赖于主观测试时，不同检查者判定关节不稳定的阈值各不相同，手术干预的阈值也随之不同。在此情况下寻求第二诊疗意见并非出于不信任，而是对已知存在局限性的测试的合理应对。

腕部骨折后，大多数尺侧疼痛会自行缓解

对于桡骨远端骨折后出现腕部疼痛的患者而言，这是最具实用价值的发现。一项全面综述得出结论：大多数桡骨远端骨折后出现的尺侧腕部问题，最初可采用非手术方式治疗，通常持续一年以上，预期随着时间推移会有显著改善 [2]。

一年比大多数人预期要等待的时间更长，在医患双方的诊疗过程中，早期干预的诱惑都很强烈。同一项综述中提到的例外情况既重要又具体：早期明显的关节半脱位，若物理上阻碍前臂旋转，则需要处理而非观察 [2]。

因此，默认策略是耐心观察，并有明确的理由来放弃这一策略。

当需要补救手术时，选择比表面看起来更精细

如果关节已破坏且非手术治疗确实失败，经典选择是 Darrach 手术（切除尺骨远端）和 Sauvé-Kapandji 手术（融合关节并在近端制造间隙以允许旋转）。

一项比较两者的系统综述发现，无论基础病理如何，患者满意度相当，在关节活动度、肌力和整体功能方面的改善也相似 [3]。差异在于再手术率，Sauvé-Kapandji 手术的再手术率更高 [3]。

这是一个清晰的鉴别点。当两种手术产生相同结果时，需要更少后续手术的手术具有优势，尽管 Sauvé-Kapandji 手术在需要保留腕骨尺骨支撑的情况下仍保留其作用，而这正是该手术被设计出来的原因。

尺骨撞击症是另一种具有特定解决方案的问题

由尺骨相对过长引起的尺侧疼痛，即尺骨撞击综合征，其治疗旨在缩短负荷路径，方法包括截短尺骨干或关节镜下切除尺骨头穹顶。一项针对 311 例患者的荟萃分析发现，两种方法均有效，且 关节镜下楔形切除术并发症更少，再手术率更低 [4]。

骨干截骨术涉及内固定钢板、骨愈合过程以及截骨端不愈合的可能性；而关节镜手术可避免上述三种情况。在解剖条件适宜的情况下，这是一个有意义的差异。

参考文献

[1] Christy M, Wright DJ, Goldfarb CA. 评估远端桡尺关节不稳定性的策略：现状及对改进工具的需求. J Hand Surg Am. 2025;50(12):1505-14. https://doi.org/10.1016/j.jhsa.2025.06.021

[2] Giddins G. 远端桡骨骨折后的远端桡尺关节：何时以及如何治疗疼痛、僵硬或不稳定性？ J Hand Surg Eur Vol. 2023;48(3):230-45. https://doi.org/10.1177/17531934221140238

[3] Lamont S, Debkowska M, Johnsen P, Froehle A, Cotterell IH, Isaacs J. Darrach 手术和 Sauvé-Kapandji 手术的结果：系统综述. Hand (N Y). 2022;19(1):68-73. https://doi.org/10.1177/15589447221107697

[4] Shi H, Huang Y, Shen Y, Wu K, Zhang Z, Li Q. 关节镜下垫片切除术与尺骨短缩截骨术治疗尺骨撞击综合征：系统综述和荟萃分析. J Orthop Surg Res. 2024;19(1). https://doi.org/10.1186/s13018-024-04611-4

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.

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)

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Considerations for the public: By using one of our public licenses, a licensor grants the public permission to use the licensed material under specified terms and conditions. If the licensor's permission is not necessary for any reason--for example, because of any applicable exception or limitation to copyright--then that use is not regulated by the license. Our licenses grant only permissions under copyright and certain other rights that a licensor has authority to grant. Use of the licensed material may still be restricted for other reasons, including because others have copyright or other rights in the material. A licensor may make special requests, such as asking that all changes be marked or described. Although not required by our licenses, you are encouraged to respect those requests where reasonable. More considerations for the public: wiki.creativecommons.org/Considerations_for_licensees

Creative Commons Attribution-NonCommercial 4.0 International Public License

By exercising the Licensed Rights (defined below), You accept and agree to be bound by the terms and conditions of this Creative Commons Attribution-NonCommercial 4.0 International Public License ("Public License"). To the extent this Public License may be interpreted as a contract, You are granted the Licensed Rights in consideration of Your acceptance of these terms and conditions, and the Licensor grants You such rights in consideration of benefits the Licensor receives from making the Licensed Material available under these terms and conditions.

Section 1 -- Definitions.

a. Adapted Material means material subject to Copyright and Similar Rights that is derived from or based upon the Licensed Material and in which the Licensed Material is translated, altered, arranged, transformed, or otherwise modified in a manner requiring permission under the Copyright and Similar Rights held by the Licensor. For purposes of this Public License, where the Licensed Material is a musical work, performance, or sound recording, Adapted Material is always produced where the Licensed Material is synched in timed relation with a moving image.

b. Adapter's License means the license You apply to Your Copyright and Similar Rights in Your contributions to Adapted Material in accordance with the terms and conditions of this Public License.

c. Copyright and Similar Rights means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.

d. Effective Technological Measures means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.

e. Exceptions and Limitations means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.

f. Licensed Material means the artistic or literary work, database, or other material to which the Licensor applied this Public License.

g. Licensed Rights means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.

h. Licensor means the individual(s) or entity(ies) granting rights under this Public License.

i. NonCommercial means not primarily intended for or directed towards commercial advantage or monetary compensation. For purposes of this Public License, the exchange of the Licensed Material for other material subject to Copyright and Similar Rights by digital file-sharing or similar means is NonCommercial provided there is no payment of monetary compensation in connection with the exchange.

j. Share means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.

k. Sui Generis Database Rights means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.

l. You means the individual or entity exercising the Licensed Rights under this Public License. Your has a corresponding meaning.

Section 2 -- Scope.

a. License grant.

1. Subject to the terms and conditions of this Public License, the Licensor hereby grants You a worldwide, royalty-free, non-sublicensable, non-exclusive, irrevocable license to exercise the Licensed Rights in the Licensed Material to:

a. reproduce and Share the Licensed Material, in whole or in part, for NonCommercial purposes only; and

b. produce, reproduce, and Share Adapted Material for NonCommercial purposes only.

2. Exceptions and Limitations. For the avoidance of doubt, where Exceptions and Limitations apply to Your use, this Public License does not apply, and You do not need to comply with its terms and conditions.

3. Term. The term of this Public License is specified in Section 6(a).

4. Media and formats; technical modifications allowed. The Licensor authorizes You to exercise the Licensed Rights in all media and formats whether now known or hereafter created, and to make technical modifications necessary to do so. The Licensor waives and/or agrees not to assert any right or authority to forbid You from making technical modifications necessary to exercise the Licensed Rights, including technical modifications necessary to circumvent Effective Technological Measures. For purposes of this Public License, simply making modifications authorized by this Section 2(a) (4) never produces Adapted Material.

5. Downstream recipients.

a. Offer from the Licensor -- Licensed Material. Every recipient of the Licensed Material automatically receives an offer from the Licensor to exercise the Licensed Rights under the terms and conditions of this Public License.

b. No downstream restrictions. You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.

6. No endorsement. Nothing in this Public License constitutes or may be construed as permission to assert or imply that You are, or that Your use of the Licensed Material is, connected with, or sponsored, endorsed, or granted official status by, the Licensor or others designated to receive attribution as provided in Section 3(a)(1)(A)(i).

b. Other rights.

1. Moral rights, such as the right of integrity, are not licensed under this Public License, nor are publicity, privacy, and/or other similar personality rights; however, to the extent possible, the Licensor waives and/or agrees not to assert any such rights held by the Licensor to the limited extent necessary to allow You to exercise the Licensed Rights, but not otherwise.

2. Patent and trademark rights are not licensed under this Public License.

3. To the extent possible, the Licensor waives any right to collect royalties from You for the exercise of the Licensed Rights, whether directly or through a collecting society under any voluntary or waivable statutory or compulsory licensing scheme. In all other cases the Licensor expressly reserves any right to collect such royalties, including when the Licensed Material is used other than for NonCommercial purposes.

Section 3 -- License Conditions.

Your exercise of the Licensed Rights is expressly made subject to the following conditions.

a. Attribution.

1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

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.