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Acromioclavicular Joint Injury (Shoulder Separation)

Acromioclavicular separation: Rockwood grading and CC reconstruction (corpus-synthesised).

Overview

Acromioclavicular joint injuries present a lack of consensus on the optimal surgical technique, resulting in unique complication profiles based on the technique used [1]. Treatment for bipolar clavicle injury, involving posterior dislocation of the acromioclavicular joint and anterior dislocation of the sternoclavicular joint, should primarily aim to restore the anatomy of both joints [3]. In acute high-grade instabilities, there is a high prevalence (30%) of concomitant glenohumeral pathologies; some indicate additional surgical therapy and could be missed by an isolated open AC repair [8].

Anatomic acromioclavicular–coracoclavicular reconstruction using a single tendon graft provides greater stability and stronger load to failure characteristics than isolated coracoid cerclage reconstruction [4]. Reconstruction of coracoclavicular and acromioclavicular ligaments with a double-bundle semitendinosus autograft and cortical buttons for chronic dislocations results in significant improvement in shoulder function without complications related to clinical symptoms after a mean follow-up of 31.7 months [5]. Use of the pectoralis minor tendon as a local source of autograft tissue in acromioclavicular joint reconstruction is feasible and potentially advantageous [10].

Both open and arthroscopic repair of acute acromioclavicular joint dislocation using a single tight rope yield good clinical results, but the arthroscopic technique is more expensive and has a longer surgical time [6]. There are no statistically significant differences between suture button and hook plate techniques for acute unstable acromioclavicular joint dislocation regarding operation time, coracoclavicular distance, complications, or loss of reduction [7]. A rare case of acute traumatic subacromial type VI acromioclavicular injury was treated with open reduction and distal clavicle resection, noting that joint obliquity may predispose patients to this locked dislocation mechanism [9]. In a survey of treatment for acromioclavicular joint separations in Japan, only 11 members opted for conservative treatment, while approximately 95% of physicians chose surgery [11].

Anatomy & Pathophysiology

Acromioclavicular joint injuries involve the acromioclavicular joint complex, including its anatomy and biomechanics [2]. Bipolar clavicle injury is defined as posterior dislocation of the acromioclavicular joint with anterior dislocation of the sternoclavicular joint [3].

Osseous Considerations: The synchondrosis of an os acromiale can be injured following trauma, though rarely [12]. Distal clavicle excision for arthritis has a higher failure rate in patients with prior low-grade separations [13]. A center-center or medial-center tunnel orientation results in a higher peak load to failure, which may lessen the risk of coracoid fracture during drilling with a 6-mm cannulated drill bit [22]. Attempts to create a tunnel based on the anatomic footprints for transclavicular-transcoracoid drilling results in a nearly universal medial cortical breach of the coracoid process [23].

Ligamentous & Kinematic Integrity: There is a high prevalence (30%) of concomitant glenohumeral pathologies among acute high-grade acromioclavicular joint instabilities [8]. Some concomitant glenohumeral pathologies indicate additional surgical therapy and could be missed by an isolated open AC repair [8]. Anatomic acromioclavicular reconstructions are biomechanically superior to nonanatomic techniques [13]. None of the described procedures for graft fixation restores the kinematics of the native coracoclavicular ligaments [17]. The A-P and S-I translational biomechanical characteristics of the AC joint were restored using a technique utilizing a single continuous intramedullary free tendon graft [21]. Only combined AC and CC reconstruction can adequately reestablish physiological horizontal ACJ stability [27].

Classification

There is no consensus on a gold standard for diagnostic measures needed to classify acute acromioclavicular joint injuries [14]. Additionally, a lack of consensus exists on the optimal surgical technique for acromioclavicular joint injuries [1].

Clinical Presentation

There is no consensus on a gold standard for diagnostic measures needed to classify acute acromioclavicular joint injuries [14]. Concomitant glenohumeral pathologies are present in 30% of acute high-grade acromioclavicular joint instabilities [8]. Some concomitant glenohumeral pathologies indicate additional surgical therapy and could be missed by an isolated open acromioclavicular joint repair [8]. One in five subjects with surgically treated acute acromioclavicular joint dislocations has an associated intraarticular lesion that requires further intervention [20].

The synchondrosis of an os acromiale can be injured following trauma, although rarely [12]. Appropriate radiographic investigation for os acromiale injury includes axillary views [12]. A rare case of acute traumatic subacromial type VI acromioclavicular injury involved a locked dislocation mechanism potentially predisposed by joint obliquity [9]. Bipolar clavicle injury can present as posterior dislocation of the acromioclavicular joint with anterior dislocation of the sternoclavicular joint [3].

Investigations

There is no consensus on a gold standard for diagnostic measures needed to classify acute acromioclavicular joint injuries [14].

Plain radiography: Appropriate radiographic investigation, including axillary views, is necessary to identify injuries such as a fracture of an os acromiale with associated rupture of the coracoclavicular ligaments [12].

Other Considerations: A high prevalence (30%) of concomitant glenohumeral pathologies exists among acute high-grade acromioclavicular joint instabilities [8]. Some concomitant glenohumeral pathologies indicate additional surgical therapy and could be missed by an isolated open acromioclavicular repair [8]. The prevalence of intraarticular associated lesions after acute acromioclavicular joint injuries is 20% [20]. One in five subjects with surgically treated acute acromioclavicular joint dislocations will have an associated intraarticular lesion that requires further intervention [20].

Treatment

Non-Operative

Conservative and surgical treatments are both effective in acromioclavicular joint osteoarthritis management [19]. In Japan, approximately 95% of physicians chose surgery for acromioclavicular joint separations, while only 11 members opted for conservative treatment [11].

Operative

Indications: Restoration of the anatomy of the acromioclavicular and sternoclavicular joints should be the primary goal of treatment for bipolar clavicle injury involving posterior dislocation of the acromioclavicular joint with anterior dislocation of the sternoclavicular joint [3]. Acute traumatic subacromial type VI acromioclavicular injury can be treated with open reduction and distal clavicle resection [9]. Surgical fixations of the coracoid process and acromioclavicular joint for combined acromioclavicular joint dislocation and coracoid avulsion provide rigid stability and allow early rehabilitation with excellent functional outcome [16].

Surgical Approach / Technique: Both open and arthroscopic repair of acute acromioclavicular joint dislocation using a single tight rope yield good clinical results, but the arthroscopic technique is more expensive and has a longer surgical time [6]. Anatomic acromioclavicular–coracoclavicular reconstruction using a single tendon graft provides greater stability and stronger load to failure characteristics than isolated coracoid cerclage reconstruction [4]. Anatomic acromioclavicular joint reconstructions are biomechanically superior to nonanatomic techniques [13]. Coracoclavicular and acromioclavicular ligament reconstruction with a double-bundle semitendinosus autograft and cortical buttons for chronic acromioclavicular joint dislocations results in significant improvement in shoulder function without complications related to clinical symptoms after a mean follow-up interval of 31.7 months [5]. Use of the pectoralis minor tendon as a local source of autograft tissue in acromioclavicular joint reconstruction is feasible and potentially advantageous [10]. None of the described procedures for graft fixation at the coracoid process restores the kinematics of the native coracoclavicular ligaments [17].

Implant Selection: There are no statistically significant differences between suture button and hook plate techniques for acute unstable acromioclavicular joint dislocation regarding operation time, coracoclavicular distance, complications, and loss of reduction [7]. The 15-degree clavicular hook plate is superior to the 0-degree hook plate in reducing shoulder pain and improving postoperative recovery in the treatment of acromioclavicular joint dislocation [29]. Clavicle fracture at the suture hole is a rare complication after acromioclavicular joint reconstruction using a suture-button [15].

Other Considerations: There is a lack of consensus on the optimal surgical technique for acromioclavicular joint injuries, leading to unique complication profiles based on the technique used [1]. Distal clavicle excision for arthritis has a higher failure rate in patients with prior low-grade separations [13].

Complications

Technique-Specific Profiles: A lack of consensus on optimal surgical technique for acromioclavicular joint injuries leads to unique complication profiles based on the technique used [1]. Arthroscopic repair of acute acromioclavicular joint dislocation is more expensive and has a longer surgical time compared to open repair [6]. Treatment with hook plate or K-wires is associated with the highest complication rates among surgical techniques for acromioclavicular joint instability [34]. Modified Weaver-Dunn reconstruction has the highest unplanned reoperation rates among surgical techniques for acromioclavicular joint instability [34]. There are no statistically significant differences in complications between suture button and hook plate techniques for acute unstable acromioclavicular joint dislocation [7].

Technical Failure and Reduction Loss: Placement of the coracoid button centrally under the coracoid base is crucial to prevent failure in minimally invasive coracoclavicular ligament reconstruction using a flip button repair technique [18]. Coracoclavicular ligament reconstruction with autogenous peroneus longus tendon is associated with a high rate of loss of reduction and tunnel widening [30].

Perioperative and Associated Pathologies: Early surgery results in a reduced risk of infection and loss of reduction compared with delayed surgery for acromioclavicular joint dislocations [33]. Concomitant glenohumeral pathologies have a high prevalence (30%) in acute high-grade acromioclavicular joint instabilities and could be missed by an isolated open AC repair [8]. Clavicle fracture at the suture hole is a rare complication after acromioclavicular joint reconstruction using a suture-button [15].

Recovery

Light activity (weeks): Evidence does not specify a week range for light activity or desk work.

Full activity (months): Evidence does not specify a month range for manual work or sport.

Complete recovery / outcome plateau (months): Patients undergoing coracoclavicular and acromioclavicular ligament reconstruction with a double-bundle semitendinosus autograft and cortical buttons for chronic acromioclavicular joint dislocations achieved significant improvement in shoulder function without complications related to clinical symptoms after a mean follow-up interval of 31.7 months [5].

Rehabilitation protocol: Surgical fixations of the coracoid process and AC joint in cases of combined acromioclavicular joint dislocation and coracoid avulsion provide rigid stability and allow early rehabilitation with excellent functional outcome [16].

Functional milestones: Patients undergoing coracoclavicular and acromioclavicular ligament reconstruction with a double-bundle semitendinosus autograft and cortical buttons for chronic acromioclavicular joint dislocations achieved significant improvement in shoulder function without complications related to clinical symptoms after a mean follow-up interval of 31.7 months [5].

Other Considerations: A lack of consensus exists on the optimal surgical technique for acromioclavicular joint injuries, leading to unique complication profiles based on the technique used [1]. Anatomic acromioclavicular–coracoclavicular reconstruction using a single tendon graft provides greater stability and stronger load to failure characteristics than isolated coracoid cerclage reconstruction [4]. Both open and arthroscopic repair of acute acromioclavicular joint dislocation using a single tight rope yielded good clinical results [6]. The arthroscopic technique for acute acromioclavicular joint dislocation repair is more expensive and has a longer surgical time than the open technique [6]. There is a high prevalence (30%) of concomitant glenohumeral pathologies among acute high-grade acromioclavicular joint instabilities, some of which indicate additional surgical therapy and could be missed by an isolated open AC repair [8]. A rare case of acute traumatic subacromial type VI acromioclavicular injury was treated with open reduction and distal clavicle resection [9]. Joint obliquity may predispose patients to the locked dislocation mechanism seen in traumatic subacromial dislocation of the acromioclavicular joint [9]. Approximately 95% of physicians in Japan chose surgery for acromioclavicular joint separations, while only 11 members opted for conservative treatment [11]. The age of the patient at trauma had a significant influence on the functional outcome of minimally invasive coracoclavicular ligament reconstruction using a flip button repair technique [18]. Placement of the coracoid button centrally under the coracoid base is crucial to prevent failure in minimally invasive coracoclavicular ligament reconstruction using a flip button repair technique [18]. Restoration of the anatomy of the acromioclavicular and sternoclavicular joints should be the primary goal of treatment for bipolar clavicle injury involving posterior dislocation of the acromioclavicular joint with anterior dislocation of the sternoclavicular joint [3].

Key Evidence

  • [L4] A lack of consensus exists on the optimal surgical technique for acromioclavicular joint injuries, leading to unique complication profiles based on the technique used. (10.5435/jaaos-d-24-00696)
  • [L5] This article provides a current, in-depth treatise on all aspects of acromioclavicular joint complex injuries, including anatomy, biomechanics, evaluation, and surgical outcomes, to guide clinical decision-making. (10.1177/0363546506298022)
  • [L4] Restoration of the anatomy of the acromioclavicular and sternoclavicular joints should be the primary goal of treatment for this rare injury. (10.1016/j.jse.2010.08.016)
  • [L5] This novel single tendon anatomic acromioclavicular–coracoclavicular reconstruction provided greater stability and stronger load to failure characteristics than the isolated coracoid cerclage reconstruction. (10.1007/s00167-013-2569-x)
  • [L4] Patients who underwent the index procedure achieved significant improvement in shoulder function without complications related clinical symptom after a mean follow-up interval of 31.7 months. (10.1016/j.jse.2024.01.019)
  • [L1] Both open and arthroscopic repair of acute acromioclavicular joint dislocation yielded good clinical results, yet the arthroscopic technique is more expensive and has a longer surgical time. (10.1016/j.jse.2019.06.007)
  • [L1] However, for operation time, coracoclavicular distance, complications, and loss of reduction, there were no statistically significant differences between the techniques. (10.1177/0363546519858745)
  • [L4] This prospective study showed a high prevalence (30%) of concomitant glenohumeral pathologies, of which some indicate additional surgical therapy and could be missed by an isolated open AC repair. (10.1016/j.jse.2012.08.016)
  • [Case_report] The authors report a rare case of acute traumatic subacromial type VI acromioclavicular injury treated with open reduction and distal clavicle resection, noting that joint obliquity may predispose patients to this locked dislocation mechanism. (10.1016/j.jse.2006.03.005)
  • [L5] Use of the pectoralis minor tendon as a local source of autograft tissue in acromioclavicular joint reconstruction is both feasible and potentially advantageous. (10.1016/j.jse.2006.09.007)
  • [L5] Only 11 members opted for conservative treatment of ACJ separations, and approximately 95% of physicians chose surgery. (10.1016/j.jseint.2020.09.008)
  • [L4] This case highlights that the synchondrosis of an os acromiale can be injured following trauma, though rarely, and emphasizes the need for appropriate radiographic investigation including axillary views and a flexible surgical approach. (10.1016/j.jse.2008.02.012)
  • [L1] To date there is no consensus on a gold standard for diagnostic measures needed to classify acute AC joint injuries. (10.1186/s12891-017-1864-y)
  • [Case_report] The present case indicated that a clavicle fracture at the suture hole, although rare, is one of the complications after an acromioclavicular joint reconstruction using a suture-button. (10.1186/s12891-019-2720-z)
  • [L5] Surgical fixations of the coracoid process and AC joint provide rigid stability and allow early rehabilitation with excellent functional outcome. (10.1136/bcr-2014-208563)
  • [L5] None of the described procedures for graft fixation restores the kinematics of the native coracoclavicular ligaments. (10.1016/j.arthro.2012.08.026)
  • [L4] The age of the patient at trauma had a significant influence on the functional outcome, and placement of the coracoid button centrally under the coracoid base is crucial to prevent failure. (10.1007/s00167-013-2737-z)
  • [L4] Conservative and surgical treatments are both effective in acromioclavicular joint osteoarthritis management. (10.1007/s00167-020-06377-8)
  • [L1] One in five subjects with surgically treated acute ACJ dislocations will have an associated intraarticular lesion that requires further intervention. (10.1007/s00167-020-05917-6)
  • [L5] The A-P and S-I translational biomechanical characteristics of the AC joint were restored using the new technique described. (10.1016/j.jse.2012.09.013)
  • [L5] Our biomechanical results showed a higher peak load to failure with a center-center or medial-center tunnel orientation, which may lessen the risk of coracoid fracture during drilling with a 6-mm cannulated drill bit. (10.1016/j.arthro.2012.02.004)
  • [L5] Attempts to correct this nonanatomic configuration by creating a tunnel based on the anatomic footprints results in a nearly universal medial cortical breach of the coracoid process. (10.1016/j.jse.2011.12.008)
  • [L5] The results suggest that only combined AC and CC reconstruction can adequately reestablish physiological horizontal ACJ stability. (10.1007/s00167-014-2895-7)
  • [L3] The 15-degree hook plate is superior to the 0-degree hook plate in reducing shoulder pain and improving postoperative recovery in the treatment of AC joint dislocation. (10.1177/0300060518786910)
  • [L4] The procedure is associated with a high rate of loss of reduction and tunnel widening but no donor site morbidity. (10.1016/j.jse.2017.12.009)
  • [L2] Early surgery results in better functional and radiological outcomes with a reduced risk of infection and loss of reduction compared with delayed surgery. (10.1302/0301-620x.95b12.31802)
  • [L1] Treatment with hook plate/K-wires was associated with the highest complication rates, and modified Weaver-Dunn had the highest unplanned reoperation rates. (10.1016/j.arthro.2018.01.016)

See Also

References

[1] Acromioclavicular Separations: Complications and How to Avoid Them. Journal of the American Academy of Orthopaedic Surgeons. 2025. DOI: 10.5435/jaaos-d-24-00696

[2] Evaluation and Treatment of Acromioclavicular Joint Injuries. The American Journal of Sports Medicine. 2007. DOI: 10.1177/0363546506298022

[3] Bipolar clavicle injury: posterior dislocation of the acromioclavicular joint with anterior dislocation of the sternoclavicular joint: A report of two cases. Journal of Shoulder and Elbow Surgery. 2011. DOI: 10.1016/j.jse.2010.08.016

[4] Simultaneous anatomic reconstruction of the acromioclavicular and coracoclavicular ligaments using a single tendon graft. Knee Surgery, Sports Traumatology, Arthroscopy. 2013. DOI: 10.1007/s00167-013-2569-x

[5] Coracoclavicular and acromioclavicular ligament reconstruction with a double-bundle semitendinosus autograft and cortical buttons for chronic acromioclavicular joint dislocations: clinical and imaging outcomes. Journal of Shoulder and Elbow Surgery. 2024. DOI: 10.1016/j.jse.2024.01.019

[6] Open versus modified arthroscopic treatment of acute acromioclavicular dislocation using a single tight rope: randomized comparative study of clinical outcome and cost-effectiveness. Journal of Shoulder and Elbow Surgery. 2019. DOI: 10.1016/j.jse.2019.06.007

[7] Suture Button Versus Hook Plate for Acute Unstable Acromioclavicular Joint Dislocation: A Meta-analysis. The American Journal of Sports Medicine. 2019. DOI: 10.1177/0363546519858745

[8] Prevalence and pattern of glenohumeral injuries among acute high-grade acromioclavicular joint instabilities. Journal of Shoulder and Elbow Surgery. 2013. DOI: 10.1016/j.jse.2012.08.016

[9] Traumatic subacromial dislocation of the acromioclavicular joint: A case report. Journal of Shoulder and Elbow Surgery. 2007. DOI: 10.1016/j.jse.2006.03.005

[10] Anatomy of the pectoralis minor tendon and its use in acromioclavicular joint reconstruction. Journal of Shoulder and Elbow Surgery. 2007. DOI: 10.1016/j.jse.2006.09.007

[11] Treatment of acromioclavicular joint separations in Japan: a survey. JSES International. 2021. DOI: 10.1016/j.jseint.2020.09.008

[12] Fracture of an os acromiale with associated rupture of the coracoclavicular ligaments. Journal of Shoulder and Elbow Surgery. 2008. DOI: 10.1016/j.jse.2008.02.012

[13] Chapter 76 Disorders of the Acromioclavicular Joint. 2019.

[14] The acutely injured acromioclavicular joint – which imaging modalities should be used for accurate diagnosis? A systematic review. BMC Musculoskeletal Disorders. 2017. DOI: 10.1186/s12891-017-1864-y

[15] Clavicle fracture at the suture hole after acromioclavicular joint reconstruction using a suture-button: a case report. BMC Musculoskeletal Disorders. 2019. DOI: 10.1186/s12891-019-2720-z

[16] Combined acromioclavicular joint dislocation and coracoid avulsion in an adult. BMJ Case Reports. 2015. DOI: 10.1136/bcr-2014-208563

[17] Tendon Graft Fixation Sites at the Coracoid Process for Reconstruction of the Coracoclavicular Ligaments: A Kinematic Evaluation of Three Different Surgical Techniques. Arthroscopy. 2013. DOI: 10.1016/j.arthro.2012.08.026

[18] Why does minimally invasive coracoclavicular ligament reconstruction using a flip button repair technique fail? An analysis of risk factors and complications. Knee Surgery, Sports Traumatology, Arthroscopy. 2013. DOI: 10.1007/s00167-013-2737-z

[19] No differences between conservative and surgical management of acromioclavicular joint osteoarthritis: a scoping review. Knee Surgery, Sports Traumatology, Arthroscopy. 2021. DOI: 10.1007/s00167-020-06377-8

[20] The prevalence of intraarticular associated lesions after acute acromioclavicular joint injuries is 20%. A systematic review and meta‐analysis. Knee Surgery, Sports Traumatology, Arthroscopy. 2020. DOI: 10.1007/s00167-020-05917-6

[21] Biomechanical evaluation of a coracoclavicular and acromioclacicular ligament reconstruction technique utilizing a single continuous intramedullary free tendon graft. Journal of Shoulder and Elbow Surgery. 2013. DOI: 10.1016/j.jse.2012.09.013

[22] Biomechanical Evaluation of Effect of Coracoid Tunnel Placement on Load to Failure of Fixation During Repair of Acromioclavicular Joint Dislocations. Arthroscopy. 2012. DOI: 10.1016/j.arthro.2012.02.004

[23] Anatomic considerations of transclavicular-transcoracoid drilling for coracoclavicular ligament reconstruction. Journal of Shoulder and Elbow Surgery. 2013. DOI: 10.1016/j.jse.2011.12.008

[27] Value of additional acromioclavicular cerclage for horizontal stability in complete acromioclavicular separation: a biomechanical study. Knee Surgery, Sports Traumatology, Arthroscopy. 2014. DOI: 10.1007/s00167-014-2895-7

[29] Fifteen-degree clavicular hook plate achieves better clinical outcomes in the treatment of acromioclavicular joint dislocation. Journal of International Medical Research. 2018. DOI: 10.1177/0300060518786910

[30] A prospective study of coracoclavicular ligament reconstruction with autogenous peroneus longus tendon for acromioclavicular joint dislocations. Journal of Shoulder and Elbow Surgery. 2018. DOI: 10.1016/j.jse.2017.12.009

[33] Controversies relating to the management of acromioclavicular joint dislocations. The Bone & Joint Journal. 2013. DOI: 10.1302/0301-620x.95b12.31802

[34] Acromioclavicular and Coracoclavicular Ligament Reconstruction for Acromioclavicular Joint Instability: A Systematic Review of Clinical and Radiographic Outcomes. Arthroscopy. 2018. DOI: 10.1016/j.arthro.2018.01.016

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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.