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Distal radioulnar joint hemiresection

37 citationsUpdated Aug 2026

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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]. Severely damaged and painful distal radioulnar joints can be reconstructed by resection arthroplasty or by hemi- or total arthroplasty [4].

Management of distal radioulnar joint instability covers anatomic and biomechanical advances, categorization of instability, and treatment strategies including percutaneous, arthroscopic, soft-tissue, osteotomy and arthroplasty techniques [13]. Ulnar shortening osteotomy is a good option to treat patients with ulnar impaction syndrome regardless of the distal radioulnar joint angle [6]. Distal radioulnar joint ligament reconstruction is indicated when native ligaments are not reparable, provided there is no radius or ulna bony deformity or arthritis of the distal radioulnar joint [8].

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 [11]. When appropriate patient selection criteria are met, partial and total ulnar head replacement typically produce reliable results [21]. 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 [16].

Anatomy & Pathophysiology

Osseous

Anatomical variations in the sigmoid notch and ulnar head significantly influence joint mechanics and treatment outcomes [30]. Stability of the distal radioulnar joint is maintained by two factors: compression between the articulating surfaces and tension in the ligament in the direction of its fibers [29]. Radial lengthening did not demonstrate a benefit in improving distal radioulnar joint stability in a triangular fibrocartilage complex injury model [32].

Ligamentous

The flexor carpi ulnaris and extensor carpi ulnaris muscles serve as dynamic stabilizers of the distal radioulnar joint [9]. The peripheral triangular fibrocartilage complex (TFCC) has healing potential, which allows closed treatment to be frequently successful for isolated acute dislocations [31]. Distal radioulnar joint instability is often an underestimated lesion requiring systematic clinical examination and imaging for detection [7].

Kinematics

Intra-articular pressures within the distal radioulnar joint change with forearm rotations, with the highest pressure recorded in supination under no disruption-no load, no disruption-loaded, and disrupted TFCC conditions [33].

Classification

Anatomic and Biomechanical Principles: Successful salvage of failed distal radioulnar joint reconstruction requires understanding normal anatomy, biomechanics, and modes of failure of the primary procedure [1]. A thorough knowledge of the anatomy and kinematics of the distal radioulnar joint is necessary to manage pathologic conditions [3]. The functional anatomy and pathomechanics of the distal radioulnar joint emphasize the interaction between ligaments, muscles, and bones for stability [17].

Treatment Modalities: Surgeons recommended distal radioulnar joint treatment in 67% (404 of 607) of scenarios, most commonly cast immobilization in 41% (247 of 607) [5]. Advances in minimally invasive surgical techniques have transformed the management of distal radioulnar joint instability [25].

Prosthetic Considerations: There is presently no evidence that ulnar head and total radio-ulnar joint prostheses produce long-lasting results [11].

Other Considerations: There is no clear clinical advantage to fixing the ulnar styloid or reinserting the triangular fibrocartilage complex in all cases of instability after surgical treatment of distal radial fractures, though debate remains regarding specific fracture patterns [35].

Clinical Presentation

Chronic distal radioulnar joint instability stems from various traumatic injuries and, if left untreated, leads to chronic functional impairment, pain, and arthritis [12]. Conventional radiography serves as the initial imaging modality to exclude or diagnose wrist pathology; when findings are inconclusive, high resolution 3 Tesla MRI is advised [18].

Interpretation of MRI signal changes and arthroscopic findings in the distal radioulnar ligaments and central disc exhibits substantial surgeon-to-surgeon variation. This variability raises concerns regarding overdiagnosis and overtreatment versus underdiagnosis [19].

Stabilization of the ulnar stump alleviates pain and improves forearm rotation and functional outcomes. However, no direct correlation exists between radioulnar convergence and patient outcomes [14].

Surgical outcomes for distal radioulnar joint management in rheumatoid arthritis are optimal when performed before the patient displays severe joint destruction, fixed contractures, subluxation, or dislocation [34].

Investigations

Salvage of failed distal radioulnar joint reconstruction requires a thorough understanding of normal anatomy, biomechanics, and the modes of failure of the primary procedure [1]. Imaging the DRUJ requires knowledge of the complex bony, muscular, and ligamentous anatomy [36].

Plain radiography: Standard and alternative exposures of the wrist joint and DRUJ are discussed, with case examples illustrating their use [10]. Conventional radiography should be the first imaging modality to exclude or diagnose wrist pathology [18]. Standard well-positioned radiography is the appropriate first step for imaging the DRUJ [36]. Coronal shift should be added to the classic measures of distal radius fracture reduction because of its fundamental role in distal radioulnar joint stability [23]. The occurrence of osteoarthritis of the scaphotrapeziotrapezoid and distal radioulnar joints was affected by the presence of osteoarthritis of the adjacent joint [38].

MRI: When conventional radiography is inconclusive, high resolution 3 Tesla MRI is advised [18]. High-resolution MRI helps delineate ligamentous structures of the DRUJ [36].

CT: Dynamic CT is indicated for clinical instability of the DRUJ [36].

Other Considerations: 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 [8]. Future efforts to develop reliable and quantifiable methods for analyzing DRUJ instability are essential for improving the management and treatment of this condition [39].

Treatment

Non-Operative

The provided evidence does not support specific non-operative conservative options such as weight loss, physical therapy, NSAIDs, or injections for this section.

Operative

Indications: Treatment goals in the acute setting should be to prevent future instability or incongruency of the distal radioulnar joint [20]. In the chronic setting, goals should be to restore stability and congruency to allow for painless, full motion [20].

Surgical Approach / Technique: Indirect ulnar shortening by distraction through the distal radius fracture site provides a simple and novel strategy for the management of persistent distal radioulnar joint instability during volar plating [22]. This technique obviates the need for prolonged immobilization or to alter standard postoperative protocols [22]. The combined extensor retinaculum capsulorrhaphy and suture repair effectively restores stability to both the distal radioulnar joint and ulnocarpal joint in patients with triangular fibrocartilage complex-related ulnocarpal instability [37]. This procedure considerably reduces pain and preserves range of motion [37].

Implant Selection: Both APTIS distal radioulnar joint arthroplasty and ulnar head replacement yield substantial functional improvements and good long-term survivorship [15].

Complications

Instability: Both APTIS DRUJ arthroplasty and ulnar head replacement yield substantial functional improvements and good long-term survivorship [15]. 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 [22]. Adding a distally based longitudinal extensor carpi ulnaris strip to ulnar shortening osteotomy seems to be an effective treatment in patients with irreparable degenerative triangular fibrocartilage complex injuries due to ulnar impaction syndrome [40].

Other Considerations: This report documents the original anatomic DRUJ reconstruction technique described by Sanders and our procedure modifications, representing an important evolutionary step in the history of surgical treatment for DRUJ instability [24].

Recovery

Light activity (weeks): Evidence does not specify a timeline for light activity, desk work, or driving following distal radioulnar joint hemiresection.

Full activity (months): Evidence does not specify a timeline for manual work, sport, or full range of motion and strength return.

Complete recovery / outcome plateau (months): The mean follow-up for the Aptis total distal radioulnar joint prosthesis rescue option was 9.7 years [16].

Rehabilitation protocol: Evidence does not specify physical therapy phasing, immobilisation duration, weight-bearing or range of motion progression, or sling/brace removal timing.

Functional milestones: Stabilization of the ulnar stump alleviates pain and improves forearm rotation and functional outcomes [14]. The Aptis total distal radioulnar joint prosthesis provides significant improvements in range of motion, grip strength, and pain scores [16]. There is no direct correlation between radioulnar convergence and patient outcomes [14].

Other Considerations: The Aptis total distal radioulnar joint prosthesis is a good rescue option for patients with previous failed surgical procedures [16].

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] Severely damaged and painful distal radioulnar joints can be reconstructed by resection arthroplasty or by hemi- or total arthroplasty. [4] (10.1016/j.hcl.2020.07.008)
  • [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)
  • [L4] Ulnar shortening osteotomy is a good option to treat patients with ulnar impaction syndrome regardless of the distal radioulnar joint angle. [6] (10.1177/17531934241262931)
  • [L5] Distal radioulnar joint instability is often an underestimated lesion requiring systematic clinical examination and imaging for detection. [7] (10.1007/s00402-020-03371-0)
  • [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. [8] (10.1016/j.hcl.2020.07.004)
  • [L4] The flexor carpi ulnaris and extensor carpi ulnaris muscles serve as dynamic stabilizers of the distal radioulnar joint. [9] (10.1177/17531934231168299)
  • [L5] Standard and alternative exposures of the wrist joint and DRUJ are discussed, with case examples illustrating their use. [10] (10.1016/j.hcl.2014.07.003)
  • [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. [11] (10.1054/jhsb.2002.0815)
  • [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] 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. [13] (10.1177/1753193414527052)
  • [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. [14] (10.1016/j.hcl.2014.12.003)
  • [L2] Both APTIS DRUJ arthroplasty and ulnar head replacement yield substantial functional improvements and good long-term survivorship. [15] (10.1177/17531934261415827)
  • [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. [16] (10.1177/17531934231192375)
  • [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. [17] (10.1177/1753193417693170)
  • [L2] Conventional radiography should be the first imaging modality to exclude or diagnose wrist pathology; when inconclusive, high resolution 3 Tesla MRI is advised. [18] (10.1177/1753193416683876)
  • [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. [19] (10.1177/17531934241254705)
  • [L5] Treatment goals in the acute setting should be to prevent future instability or incongruency of the distal radioulnar joint, while goals in the chronic setting should be to restore stability and congruency to allow for painless, full motion. [20] (10.1016/j.hcl.2021.02.011)
  • [L4] When appropriate patient selection criteria are met, partial and total ulnar head replacement typically produce reliable results. [21] (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. [22] (10.1016/j.jhsa.2018.02.030)
  • [L5] Coronal shift should be added to the classic measures of distal radius fracture reduction because of its fundamental role in distal radioulnar joint stability. [23] (10.1016/j.jhsa.2014.08.022)
  • [L4] This report documents the original anatomic DRUJ reconstruction technique described by Sanders and our procedure modifications, representing an important evolutionary step in the history of surgical treatment for DRUJ instability. [24] (10.1016/j.jhsa.2020.08.001)
  • [L5] Advances in minimally invasive surgical techniques have transformed the management of DRUJ instability. [25] (10.1177/17531934261417561)
  • [L5] Stability of the distal radioulnar joint is maintained by two factors: compression between the articulating surfaces and tension in the ligament in the direction of its fibers. [29] (10.1016/j.hcl.2010.05.002)
  • [L5] Anatomical variations in the sigmoid notch and ulnar head significantly influence joint mechanics and treatment outcomes. [30] (10.1016/j.hcl.2012.03.002)
  • [L5] This article reviews the anatomy, biomechanics, and treatment of acute dislocations of the distal radioulnar joint and distal ulna fractures, emphasizing that closed treatment is frequently successful for isolated dislocations due to the healing potential of the peripheral TFCC. [31] (10.1016/j.hcl.2010.05.009)
  • [L5] Radial lengthening did not demonstrate a benefit in improving DRUJ stability in a triangular fibrocartilage complex injury model. [32] (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. [33] (10.1016/j.jhsa.2023.11.015)
  • [L5] Surgical outcomes are best when performed before the patient displays severe joint destruction, fixed contractures, subluxation, or dislocation. [34] (10.1016/j.hcl.2005.08.009)
  • [L5] While anatomical reduction of the distal radius is key, there is no clear clinical advantage to fixing the ulnar styloid or reinserting the TFCC in all cases of instability, though debate remains regarding specific fracture patterns. [35] (10.1177/17531934241268980)
  • [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. [36] (10.1016/j.hcl.2010.07.001)
  • [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. [37] (10.1016/j.jhsg.2025.100806)
  • [L4] The occurrence of osteoarthritis of the scaphotrapeziotrapezoid and distal radioulnar joints was affected by the presence of osteoarthritis of the adjacent joint. [38] (10.1016/j.jhsa.2023.05.009)
  • [L5] Future efforts to develop reliable and quantifiable methods for analyzing DRUJ instability are essential for improving the management and treatment of this condition. [39] (10.1016/j.jhsa.2025.06.021)
  • [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. [40] (10.1177/17531934231197942)

See Also

References

[1] Salvage of Failed Distal Radioulnar Joint Reconstruction. Hand Clinics. 2010. DOI: 10.1016/j.hcl.2010.05.004

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

[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] 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

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

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

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

[10] Exposures of the Wrist and Distal Radioulnar Joint. Hand Clinics. 2014. DOI: 10.1016/j.hcl.2014.07.003

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

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

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

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

[15] 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

[16] 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

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

[18] Diagnostic modalities for distal radioulnar joint. Journal of Hand Surgery (European Volume). 2016. DOI: 10.1177/1753193416683876

[19] 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

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

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

[22] 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

[23] Coronal Shift of Distal Radius Fractures: Influence of the Distal Interosseous Membrane on Distal Radioulnar Joint Instability. The Journal of Hand Surgery. 2015. DOI: 10.1016/j.jhsa.2014.08.022

[24] The Original Anatomic Reconstruction of Palmar and Dorsal Radioulnar Ligaments for Distal Radioulnar Joint Instability. The Journal of Hand Surgery. 2020. DOI: 10.1016/j.jhsa.2020.08.001

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

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

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

[31] Acute Dislocations of the Distal Radioulnar Joint and Distal Ulna Fractures. Hand Clinics. 2010. DOI: 10.1016/j.hcl.2010.05.009

[32] 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

[33] 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

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

[35] 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

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

[37] 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

[38] 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

[39] Assessment Strategies for Distal Radioulnar Joint Instability: Current State and a Need for Improved Tools. The Journal of Hand Surgery. 2025. DOI: 10.1016/j.jhsa.2025.06.021

[40] 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

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Section 3 -- License Conditions.

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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.